Siste publikasjoner fra Hybrid Technology Hub

• Molinaro, Antonio; Braadland, Peder Rustøen; Carpino, Guido; Carreras, Alba; Nikolaidis, Marios & Hanzely, Petra [Vis alle 40 forfattere av denne artikkelen] (2026). Gut microbiota-derived imidazole propionate promotes primary sclerosing cholangitis via p38 signalling. Nature Metabolism. 8(9), s. 1910–1925. doi: 10.1038/s42255-026-01600-1. Fulltekst i vitenarkiv Vis sammendrag

  Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease of the bile ducts that can lead to biliary cancer and end-stage liver disease. PSC is associated with inflammatory bowel disease and an altered gut microbiota. However, the molecular mechanisms underlying gut–liver interactions in PSC remain poorly characterized. Here we show that the gut microbiota-derived metabolite imidazole propionate (ImP) is a disease driver in PSC. Individuals with PSC have higher circulating ImP levels than individuals with related conditions, and high ImP levels predict reduced survival in PSC. Cholangiocytes exposed to ImP show activated mammalian target of rapamycin complex 1 (mTORC1) signalling and secrete pro-inflammatory and pro-fibrogenic factors. Chronic administration of ImP to mice induces liver inflammation and fibrosis through a p38-dependent mechanism, upstream of mTORC1. We propose that chronic exposure to ImP induces cholangiocyte injury, which alone or in concert with other factors causes clinical worsening of PSC. Therefore, targeting ImP production or signalling may represent therapeutic avenues in PSC.

• Demir, Ali Aslan; Combriat, Thomas Michel Daniel; Heyward, Catherine Anne; Tiainen, Hanna; Carlier, Aurélie & Dysthe, Dag Kristian (2026). A cellular automaton model of osteogenic differentiation reveals identifiability limits of endpoint assays. Frontiers in Systems Biology. 6. doi: 10.3389/fsysb.2026.1872774. Fulltekst i vitenarkiv Vis sammendrag

  Introduction Standard differentiation assays sample cell states only at discrete time points, while the underlying progression unfolds continuously and heterogeneously across cells. As a result, different combinations of proliferation, commitment, and maturation dynamics can converge to similar endpoint measurements. This many-to-one mapping between latent trajectories and observable readouts constitutes a partially observed inverse problem that limits mechanistic interpretation. Although this ambiguity is inherent to many experimental systems, it is rarely examined using models that connect cell-state dynamics to assay-level quantities. Methods We present OsteoMin, a coarse-grained cellular automaton that links stochastic transitions between pre-osteoblast and osteoblast states to experimentally measurable readouts of alkaline phosphatase activity, collagen deposition, and mineralization. Model parameters were constrained using literature-reported kinetics and evaluated against dexamethasone and menaquinone-4 perturbations. The framework enables systematic analysis of how cell-state progression, matrix maturation, and external perturbations shape differentiation outcomes. Results OsteoMin reproduces qualitative assay trends and quantifies the identifiability limits of endpoint assays. Distinct perturbation families often produce similar endpoint responses (macro-F1 ≈ 0.42$), indicating limited discriminative power. Incorporating temporal trajectories improves separability (macro-F1 ≈ 0.78$), demonstrating that most identifiable information resides in marker dynamics rather than terminal measurements. Sobol analysis shows that early markers depend on proliferation timing, whereas late mineralization is governed by nonlinear matrix maturation and parameter interactions. Discussion These results show that endpoint assays constrain overall progression but do not uniquely identify underlying mechanisms. OsteoMin provides a framework linking differentiation dynamics to assay observables and a basis for assessing identifiability in endpoint-driven systems.

• Hoel, Håvard; Petkowicz, Carmen; Eidsvåg, Victoria; Øynebråten, Inger; Corthay, Alexandre Benoit & Maurer, Juliana Bello Baron [Vis alle 7 forfattere av denne artikkelen] (2026). Comparative toll-like receptor and dectin-1a activation by structurally diverse plant polysaccharides. Carbohydrate Research. ISSN 0008-6215. 567. doi: 10.1016/j.carres.2026.110003. Fulltekst i vitenarkiv Vis sammendrag

  Naturally derived polysaccharides can activate pattern recognition receptors (PRRs) like Toll-like receptors (TLRs) and Dectin-1, but structure-activity relationships remain unclear. Here, we screened several plant-derived polysaccharides using HEK-Blue™ reporter cells expressing human Toll-like receptor (hTLR) 2, hTLR2/1, hTLR2/6, hTLR3, hTLR4, hTLR5 or hDectin-1a, THP1-Blue™ NF-κB cells and mouse bone marrow-derived macrophages to investigate the correlation between structural features and activity. The polysaccharides included pectins from Gentiana purpurea (GP-AP), Angelica archangelica subsp. archangelica (A-A2-I), Daphne mezereum (DMP-ED-I), Citrullus lanatus (FW), Coffea arabica (CAP) and Citrus sp. (CPA), an arabinogalactan protein (AGP) rich extract from Persea americana (FRAGP), and an arabinoxylan from Livistonia chinensis (LCP). Activation of THP1-Blue™ cells and BMDMs, and interaction with hTLR4 and hTLR2/6 correlated with rhamnogalacturonan-I (RG-I) backbones with galactan, including arabinogalactan-II (AG-II), side chains (GP-AP and DMP-ED-I), and by the presence of AGPs (FRAGP). The presence of 4-O-Me-GlcA in A-A2-I was seemingly negatively correlated with activation of hTLR2/6, despite presence of AG-II structures. The homogalacturonan-rich (HG) polysaccharides investigated in this study, FW, CAP and CPA, did not activate hTLR4 and hTLR2/6, suggesting that HG alone was insufficient for PRR engagement in these models. Several RG-I containing pectins activated hDectin-1a, and higher Mw generally enhanced activity. The AGP and xylose-rich polysaccharides tested in this study did not activate hDectin-1a, and the arabinoxylan LCP was inactive in all assays. None of the polysaccharides activated hTLR3 or hTLR5. In conclusion, several polysaccharides activated multiple PRRs, seemingly associated with presence of RG-I domains with neutral side chains.

• Niemi, Essi Maria; Nyman, Tuula Anneli; Attramadal, Håvard; Hoel, Henrik; Rosales, Antonio & Hisdal, Jonny [Vis alle 7 forfattere av denne artikkelen] (2026). Proteomic evaluation and comparison of native and decellularized human saphenous vein extracellular matrices. Frontiers in Bioengineering and Biotechnology. 14. doi: 10.3389/fbioe.2026.1773372. Fulltekst i vitenarkiv
• Kømurcu, Kristina Sæterdal; Zawadzka, Malgorzata Elzbieta; Meszka, Igor; Aizenshtadt, Aleksandra; Hrušková, Helena & Aakervik, Lydia Emilie [Vis alle 10 forfattere av denne artikkelen] (2026). A Validated Mass Spectrometry Platform for Oxysterol Analysis of Single Human Gastruloids and Liver Organoids. Analytical Chemistry. ISSN 0003-2700. 98(9), s. 6792–6804. doi: 10.1021/acs.analchem.5c07140. Fulltekst i vitenarkiv
• Yadav, Ajay; Richartz, Nina; Bhagwat, Sampada; Burman, Marta Maria; Munthe-Kaas, Monica Cheng & Skålhegg, Bjørn Steen [Vis alle 9 forfattere av denne artikkelen] (2026). Starvation of leukemic cells enhances DNA damage-induced apoptosis in vitro via ROS/p38 MAPK and prevents leukemia progression in fasting xenograft mice. Journal of Biological Chemistry. ISSN 0021-9258. 302(3). doi: 10.1016/j.jbc.2026.111143. Fulltekst i vitenarkiv Vis sammendrag

  Most children with acute lymphoblastic leukemia (ALL) achieve long-term survival due to intensive multimodal chemotherapy. However, the use of cytotoxic DNA-damaging agents is frequently associated with severe long-term side effects, prompting continued efforts to improve treatment strategies. This study explores the potential of starving the leukemic cells to enhance the efficacy of DNA-damaging therapy in ALL. Previous work demonstrated that cAMP signaling attenuates DNA damage-induced apoptosis in ALL cells, both in vitro and in a xenograft model. The current findings show that glucose and serum deprivation reverse the effect of cAMP, converting it from a survival factor to a promoter of DNA damage-induced apoptosis in ALL-derived cell lines and patient-derived leukemic cells in vitro. The starvation-induced sensitization was independent of p53 but was shown to require increased levels of reactive oxygen species (ROS). In turn, the elevated ROS levels enhanced the activation of the mitogen-activated protein kinase p38 (p38 MAPK). The resulting augmented cell death was inhibited both by the ROS scavenger N-acetyl cysteine and the p38 MAPK inhibitor SB 202190. The translational potential of increasing the efficacy of DNA damaging agents in starving ALL cells was supported by in vivo data showing that intermittent fasting, combined with subtherapeutic doses of irradiation, significantly inhibits the leukemia progression in a xenograft model of severe combined immunodeficiency mice.

• Schöb, Franziska Jessica; Binder, Alexander; Zamarian, Valentina; Sordi, Valeria; Scholz, Hanne & Malthe-Sørenssen, Anders [Vis alle 7 forfattere av denne artikkelen] (2026). Deep learning for predicting stem cell efficiency for use in beta cell differentiation. Scientific Reports. 16(1). doi: 10.1038/s41598-026-42830-3. Fulltekst i vitenarkiv Vis sammendrag

  Recent clinical trial data show curative potential of cell therapy for diabetes, however the cells required are a bottleneck. Cell differentiation exhibits substantial variability, even among clones of stem cells generated from the same patient. Human experts struggle to see the difference between highly- and lowly-efficient cell clones early. We therefore propose an image-based deep learning model to guide the selection of the most efficient clones. We apply different deep learning models to learn the morphological differences between good and bad stem cell clones and classify them based on phase-contrast imaging. To gain insight into the learned features, we use layer-wise relevance propagation, and Fourier-based frequency analysis. Using an EfficientNet-V2-S model, we obtain a novel early prediction for the outcome of the differentiation process from patient-derived stem cells to β -cells using imaging. Clone level accuracy is 96.7 % at 53 hours after start of differentiation. The analysis of learned features shows that the structure of the cell population is an important predictive feature. This study is a proof-of-concept that deep learning combined with label-free imaging can be highly predictive and guide selection of stem cell clones, thereby reducing cost of β -cell production.

• Bentzen, Heidi Beate; Gaillard, Maxence; Nachman, Iftach; Reumann, Daniel; Gadegaard, Nikolaj & David, Laurent [Vis alle 14 forfattere av denne artikkelen] (2026). A guide to using embedded ethics in human stem-cell-based embryo model research. Nature Cell Biology. ISSN 1465-7392. 28(4), s. 665–673. doi: 10.1038/s41556-026-01909-9. Fulltekst i vitenarkiv
• Låstad, Silja Borring; Abbasova, Nigar; Combriat, Thomas Michel Daniel & Dysthe, Dag Kristian (2026). Quantitative Phase Imaging of the Dynamics of Epithelial Monolayers. SPIE Quantitative Phase Imaging XII. 13861. doi: 10.1117/12.3084036. Fulltekst i vitenarkiv Vis sammendrag

  This study uses two different quantitative phase imaging techniques (QPI) and for the first time measures the height, volume, and mass dynamics of Madin-Darby Canine Kidney (MDCK) monolayers. We demonstrate novel methods to determine the height of confluent monolayers of cells from 2D and 3D QPI data and validate that the two methods agree. We developed a novel cell segmentation method adapted to QPI images of confluent cell layers and present a robust measure of relative error. We also demonstrate that height statistics of cells can be obtained without segmenting the images. We obtain the following precisions of cell density (1 %), height (3 %), area (5 %) and volume (6 %). Cell height varies 15-25 % over a monolayer and increases 50-100 % when cell density doubles. The average refractive index and the dry mass fraction of the cells, on the other hand, are constant over the entire density range.

• Wik, Jonas Aakre; Berge, Emma Riiser; Strømsnes, Kristine Bakklund & Skålhegg, Bjørn Steen (2025). Metabolism in the tumor microenvironment: implications for pathogenesis and therapeutics. Frontiers in Immunology. 16, s. 1–20. doi: 10.3389/fimmu.2025.1610255. Fulltekst i vitenarkiv Vis sammendrag

  The immune system protects the body against dangers that include pathogens, damage and cancer. Modern cancer therapies have sought to bolster immune responses against cancer using immunotherapy, which may include various forms of immune checkpoint therapy (ICT) in addition to methods of adoptive cell transfer (ACT), which is often associated with transfer of chimeric antigen receptor (CAR) T cells. Despite favorable outcomes in some patients and some cancers, as many as 60-80% of patients fail to benefit from ICT due to primary or adaptive resistance. This highlights the need for deeper understanding of how cancers suppress the immune system. Solid tumors, which make up approximately 90% of all cancers, are characterized by an immunosuppressive tumor microenvironment (TME). A hallmark of the TME is dysfunctional vascularization and impaired perfusion, which hinder effective drug delivery and promote hypoxia-induced metabolic reprograming in both cancer and immune cells. As the TME imposes intense metabolic stress through nutrient competition and lactate-driven acidification – both of which activates immunosuppressive pathways, targeting the TME itself may be beneficial in enhancing the efficacy of immunotherapy. Here we will briefly discuss the potential of targeting the metabolism of the TME as a means to promote normalized tumor vascularization and/or enhance anti-tumor immune responses.

• Gaddipati, Sirisha; Varsani, Anika; Rosa, Gloria de La; Dominguez-Gil, Beatriz; Colmenero, Jordi & Mendizabal, Manuel [Vis alle 17 forfattere av denne artikkelen] (2025). Age-stratified Data Highlight Worldwide Variability in Organ Donation Rates and the Potential Increase in Organ Donation. Transplantation. ISSN 0041-1337. 110(3), s. e707–e714. doi: 10.1097/tp.0000000000005564. Fulltekst i vitenarkiv Vis sammendrag

  Background. Ongoing shortages of organs for transplantation have prompted the critical question of which countries have the highest organ donation rates and how each can increase those rates. The existing metric of donors per million population is flawed because it does not sufficiently account for important differences in the underlying population, including age distributions of deaths in the population. Methods. We sought to develop a better approach to analyze country-specific data on organ donation, including deaths stratified by age, to allow assessment of performance across the world. We used death data from the World Health Organization and donation data from 17 countries across 3 continents. We calculated age group-stratified organ donation rates as donors per 1000 deaths and estimated each country’s potential to increase donation if the age group-specific donation rate mirrored that of the highest-performing country in each age group. Results. There was a 4-fold difference in overall donation rates, with far greater variability within age strata, including a 10-fold difference in donation rates for the oldest age group (70 y and older). The United States showed the greatest potential to increase donations in absolute terms (>8000 increased donors per year), whereas Argentina, Germany, and Hungary had the greatest potential in relative terms. Conclusions. Although countries may have similar overall donation rates, the breakdown within specific age groups varies widely. Examining age-specific donation rates is a necessary step for accurate international comparisons of transplant systems and can enable targeted interventions to augment donation.

• ElAbd, Hesham; Pesesky, Mitchell; Innocenti, Gabriel; Chung, Brian K.; Mahdy, Aya K.H. & Kriukova, Valeriia [Vis alle 40 forfattere av denne artikkelen] (2025). T and B cell responses against Epstein–Barr virus in primary sclerosing cholangitis. Nature Medicine. ISSN 1078-8956. 31(7), s. 2306–2316. doi: 10.1038/s41591-025-03692-w. Fulltekst i vitenarkiv Vis sammendrag

  Primary sclerosing cholangitis (PSC) is an idiopathic, progressive and incurable liver disease. Here, we aimed for systematic analyses of adaptive immune responses in PSC. By profiling the T cell repertoires of 504 individuals with PSC and 904 healthy controls, we identified 1,008 clonotypes associated with PSC. A substantial fraction of these clonotypes was restricted to known PSC human leukocyte antigen susceptibility alleles and known to target Epstein–Barr virus (EBV) epitopes. We further utilized phage-immunoprecipitation sequencing to determine antibody epitope repertoires of 120 individuals with PSC and 202 healthy controls, which showed a higher burden of anti-EBV responses in PSC than controls. EBV-specific monoclonal antibodies isolated from B cells in PSC livers corroborated convergent B and T cell responses against EBV. By analyzing electronic health records of >116 million people, we identified an association between infectious mononucleosis and PSC (odds ratio, 12; 95% confidence interval, 6.3–22.9), suggesting a link between EBV and PSC.

• Sowa, Sven T.; Kücükdisli, Murat; Mostinski, Yelena; Schaller, David A.; Vinagreiro, Carolina S. & Cirillo, Davide [Vis alle 16 forfattere av denne artikkelen] (2025). Deconstruction of Dual-Site Tankyrase Inhibitors Provides Insights into Binding Energetics and Suggests Critical Hotspots for Ligand Optimization. Journal of Medicinal Chemistry. ISSN 0022-2623. 68(7), s. 7263–7279. doi: 10.1021/acs.jmedchem.4c02845. Fulltekst i vitenarkiv
• Martinez, Mikel Amirola; Combriat, Thomas Michel Daniel; Ferencevic, Katharina; Wilhelmsen, Ingrid; Dalmao-Fernandez, Andrea & Olsen, Petter Angell [Vis alle 9 forfattere av denne artikkelen] (2025). Aspects of zone-like identity and holotomographic tracking of human stem cell-derived liver sinusoidal endothelial cells. Frontiers in Cell and Developmental Biology. 13. doi: 10.3389/fcell.2025.1528991. Fulltekst i vitenarkiv Vis sammendrag

  Introduction: Liver sinusoidal endothelial cells (LSEC) are specialized endothelial cells with unique metabolic and barrier functions adapted to the needs of the liver sinusoid. LSECs are highly sensitive to their environment, and this fragile nature causes challenges in analyzing their phenotype under in vitro conditions. Methods: In this work, we first differentiated LSEC-like cells (scLSECs) from two human pluripotent stem cell lines and characterized them by a panel of qPCR markers, immunohistochemistry, substrate oxidation for energy metabolism, scavenger function, and nitric oxide secretion. We then introduced holotomography, a technique that allows to recover quantitative and three-dimensional information about the refractive indexes of cell components, as a tool to image and track scLSEC in vitro in a minimally intrusive, label-free manner. Results and discussion: Holotomography and developed machine learning-based algorithm for image processing allowed us to describe and monitor changes in intracellular pore-like structures over time. Finally, we tested the possibility of inducing aspects of zone-specific LSEC phenotype and metabolism using culture-based treatments, which resulted in modest shifts in marker expression and metabolic activity. The presented strategy provides an advanced tool kit for investigating liver endothelial cells.

• Skourti, Eleni; Vasiliauskaite, Kotryna; Mensali, Nadia; Jabeen, Shakila; Juell, Siri & Øynebråten, Inger [Vis alle 14 forfattere av denne artikkelen] (2025). Chemoresistant tumor cell secretome potentiates immune suppression in triple negative breast cancer. Breast Cancer Research. ISSN 1465-5411. 27(1). doi: 10.1186/s13058-025-02082-x. Fulltekst i vitenarkiv Vis sammendrag

  Background Chemotherapy is an integral part of the clinical management of triple negative breast cancer (TNBC), however, development of chemoresistance occurs frequently. Tumor sensitivity to treatment is known to be strongly influenced by the immune microenvironment, signifying the predictive potential of immune alterations. How tumor cells that acquire resistance may subsequently modulate the immune microenvironment it is still not well described. Here, we investigated immunomodulation in the context of acquired chemoresistance in TNBC, focusing on the role of the secretome. Methods Bulk RNA sequencing and multiplex cytokine profiling were performed on paclitaxel-resistant and -sensitive isogenic variants of TNBC cells to reveal resistance-associated secretome alterations. The immunomodulatory influence of the tumor cell secretome was investigated by exploring its effect on monocytes, macrophages (MΦs) and T cells derived from healthy blood donors. The influence on the immune cell phenotype and activity was evaluated by measuring molecular markers and performing functional assays. To validate the clinical relevance, we utilized longitudinal -omics data from breast cancer patients refractory to standard chemotherapy in the NeoAva clinical trial. CIBERSORT was applied to transcriptomics data to infer MΦ and T cell abundance in individual tumors upon treatment. To evaluate their association with the secretome profiles, patient-matched serum cytokine data were used. Results The acquisition of chemoresistance was accompanied by enhanced secretion of cytokines. Subsequently, the resistant cell secretome affected the abundance, phenotype and activity of immune cells. Specifically, it potentiated the recruitment of monocytes, facilitated the polarization of MΦs towards the immunosuppressive M2-like phenotype, and attenuated the activation of CD8+ T cells. Data from the NeoAva clinical cohort validated the enrichment of M2 MΦs and/or the depletion of M1 MΦs after treatment in the majority of residual tumors. The MΦ-associated changes counteracted CD8+ T cell abundance and were partially associated with the cytokine-enriched secretome. Conclusion Development of chemoresistance in BC is associated with alterations in the tumor secretome, which impairs immune activation and facilitates immunosuppression. Knowledge on the immune microenvironment in residual tumors after standard chemotherapy could aid in selecting rational treatment options for this group of patients

• Vestad, Beate; Hanzely, Petra; Karaliūtė, Indrė; Ramberg, Oda Helgesen; Skiecevičienė, Jurgita & Lukoševičius, Rokas [Vis alle 12 forfattere av denne artikkelen] (2025). Modulation of Dextran Sodium Sulfate-Induced Colitis in Germ-Free Mice by Enterococcus faecalis Monocolonization. Microorganisms. 13(12). doi: 10.3390/microorganisms13122864. Fulltekst i vitenarkiv Vis sammendrag

  Inflammatory bowel diseases (IBDs), including Crohn’s disease and ulcerative colitis (UC), are characterized by chronic gastrointestinal inflammation and involve complex interactions of genetic, environmental, and immune factors. Enterococcus faecalis, a gut commensal bacterium, has been implicated in IBD pathogenesis. This study investigated the effects of monocolonization with a UC-derived E. faecalis strain on acute dextran sulfate sodium (DSS)-induced colitis in germ-free (GF) mice, focusing on epithelial injury, inflammatory markers, hematologic indices, and bacterial translocation. In DSS-treated mice, monocolonization was associated with modest and mixed effects, including a higher colitis-related disease activity score, reduced anemia, increased fecal albumin and a trend towards reduced fecal calprotectin. Despite translocation of E. faecalis to mesenteric lymph nodes, no systemic dissemination was observed. Histological analysis revealed broadly similar inflammatory patterns between DSS-treated groups, with slightly more epithelial injury observed in colonized mice. These findings suggest that E. faecalis may influence discrete aspects of DSS injury in a strain-dependent and context-specific manner, rather than broadly altering overall disease severity. This study highlights the utility of GF models for examining strain-specific host–microbe interactions and underscores that individual bacterial isolates may exert heterogeneous and selective effects on acute colitis. Further research is needed to elucidate these complex mechanisms.

• Chung, Brian K.; Jordens, Markus S.; Øgaard, Jonas Daniel Sjøberg; Reims, Henrik Mikael; Flateland, Benedicte & Luedde, Tom [Vis alle 9 forfattere av denne artikkelen] (2025). Multimodal transcriptomics identifies metallothionein as a novel pathway in primary sclerosing cholangitis. Hepatology. ISSN 0270-9139. doi: 10.1097/HEP.0000000000001432. Fulltekst i vitenarkiv Vis sammendrag

  Background and Aims: Primary sclerosing cholangitis (PSC) is a chronic inflammatory bile duct disorder of unknown etiology characterized by uneven peribiliary infiltration and liver fibrosis. To localize potential disease pathways to specific microanatomical liver regions, we combined spatial and single-nuclei transcriptomics (snRNA-seq) to analyze biopsies from a spectrum of PSC and disease control explants. Approach and Results: Liver specimens from 23 PSC (transplant indications: 4 recurrent cholangitis, 7 dysplasia, 12 cirrhosis) and 7 disease controls with cirrhosis (4 metabolic dysfunction–associated steatohepatitis, MASH; 3 alcohol-associated liver disease, ALD) were analyzed by spatial transcriptomics (76,664 spots) and 16 of the same explants were also assessed by snRNA-seq (12 PSC, 2 MASH, 2 ALD; 91,891 nuclei). PSC livers expressed a robust signature of metallothionein (MT1E, MT1G, MT1H) and acute inflammation markers (SAA1, SAA2) at the parenchyma–fibrosis interface compared to disease controls. SnRNA-seq showed that the strongest metallothionein signal originated from a subtype of APOE+ hepatocytes that, by spatial transcriptomics and immunohistochemistry, were consistently localized to the edge of fibrotic lesions in PSC explants. Biliary inflammation induced by 0.1% 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) feeding in mice resulted in significant Mt1 liver expression and liver MT1G expression correlated with AST, ALT, ALP, and bilirubin levels at the time of liver transplantation. Conclusions: Combinatorial spatial and high-resolution single-nuclei transcriptomics on the largest number of PSC liver explants to date revealed metallothionein as a novel PSC pathway that could be interrogated in future studies aiming to develop effective therapeutic interventions for PSC.

• Hanzely, Petra; Holm, Kristian; Bjørnholt, Jørgen Vildershøj; Melum, Espen; Hov, Johannes Espolin Roksund & Rasmussen, Henrik (2025). Efficacy of oral and rectal administration of human faecal microbiota transplant (FMT) in human microbiota-associated mouse models. Scientific Reports. 15(1), s. 1–10. doi: 10.1038/s41598-025-32072-0. Fulltekst i vitenarkiv Vis sammendrag

  The gut microbiome has gained significant interest due to its association with immune dysregulation, allergies, autoimmune conditions, metabolic disorders, and inflammation-associated malignancies. Understanding underlying mechanisms requires appropriate in vivo models, such as human microbiota-associated mouse models to study the microbiota–host interactions. This study compared the efficacy of oral and rectal administration of human faecal microbiota transplant (FMT) from a single donor in C57BL/6J germ-free mice as these methods are often used interchangeably. Using 16S rRNA sequencing, we quantified colonisation efficacy in luminal and tissue samples from orally- (n = 6) and rectally- (n = 6) colonised mice. We detected 84 genera in the FMT sample, 17 of which were not transferred at all, while additional 7 genera were found exclusively in rectally-colonised mice. A significantly higher proportion of amplicon sequence variants (ASVs) (33% vs. 26%; P < 0.05) and genera (32% vs. 25%; P < 0.05) were absent in orally- compared to rectally-colonised group. Some taxa showed different relative abundances in human vs. mouse samples (e.g. Alistipes and Bacteroides relatively more abundant in mice while Faecalibacterium considerably decreased). Beta diversity analysis revealed greater similarity between FMT and tissue samples irrespective of the administration route, with distinct separation of the tissue and luminal samples. Overall, rectal administration yielded more overlapping genera and ASVs with FMT, highlighting that it could have advantages compared with oral administration for microbiota establishment studies

• Nothnagel, Patrizia Maria Christiane; Meslin, Paul-Arthur Richard; Wik, Jonas Aakre; Strøm, Yunna Erika; Bjørås, Magnar & Enserink, Jorrit [Vis alle 10 forfattere av denne artikkelen] (2025). Transient SUMOylation Inhibition In Human Pre-adipocytes Stably Imprints a Transcriptional Beiging Fate. bioRxiv (preprint article). 54(6). doi: 10.1101/2025.03.07.642034. Fulltekst i vitenarkiv Vis sammendrag

  Abstract SUMOylation regulates chromatin states and transcriptional programs that preserve cellular identity, yet how transient perturbation of the SUMO pathway impacts adipocyte plasticity remains unclear. Here we show that brief pharmacologic inhibition of SUMO conjugation in human pre-adipocytes using TAK-981 primes stable de novo beige differentiation in the presence of the PPARG agonist rosiglitazone. Transient TAK-981 exposure before adipogenic induction produces long-lasting changes in the transcriptome and metabolism of mature adipocytes, including robust induction of canonical beiging markers like UCP1 and increased mitochondrial respiration. Mechanistically, ATAC-seq and transcription factor footprinting revealed immediate and durable chromatin remodeling and early mobilization of CEBP family members, followed by stable activation of CEBPA and PPARG regulatory networks. ChIP experiments demonstrated loss of H3K27me3 and gain of H3K27ac at PPAR response elements within key thermogenic enhancers, with increased PPARG occupancy across the UCP1 regulatory unit. This mechanism is enforced by enhanced cAMP-PKA-p38 signaling, and stabilization of beiging transcriptional activators. Our data support a model in which transient relief of SUMO-mediated repression unlocks dominant regulatory units, notably the UCP1 enhancer cluster, producing a monomorphic, cell type specific reprogramming toward adaptive thermogenesis. These findings identify SUMOylation as a reversible epigenetic barrier to adipocyte beiging and suggest that temporally controlled SUMO pathway inhibition combined with PPARG activation could be exploited to modulate adipose tissue thermogenic capacity. Graphical abstract SUMOylation restricts de novo differentiation of pre-adipocytes into beige adipocytes by repressing cAMP signaling and preventing epigenetic and transcriptional reprogramming of white adipocytes.

• Josifovska, Natasha; Niemi, Essi Maria; Ramalingam, Murugan; Manivasagam, Geetha; Scholz, Hanne & Petrovski, Goran (2025). A pilot study for decellularizing porcine cornea for future use in corneal regeneration. PLOS ONE. 20(12). doi: 10.1371/journal.pone.0339462. Fulltekst i vitenarkiv Vis sammendrag

  Porcine corneas were decellularized for future use in corneal regeneration by using various washing steps with 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate (CHAPS) detergent, Benzonase, and Ethylenediaminetetraacetic acid (EDTA). The quality of the decellularized corneas was assessed by quantitative and qualitative measurement of DNA content, glycosaminoglycans (GAGs), immunofluorescent staining for Collagen (Col) I, V, Keratocan, Fibronectin, Laminin, Lumican and Decorin, and Transmission Electron Microscopy (TEM) to observe the structure of the collagen fibrils was used. The decellularization process showed 99.5% DNA content reduction in the corneas and a similar pattern was observed in the preservation of GAGs. Hematoxylin & Eosin (H&E) and immunofluorescent staining showed no presence of cell nuclei, while Alcian blue staining confirmed the presence of GAGs. Col I, V, Keratocan, Fibronectin, Laminin, Lumican and Decorin were still present in the decellularized corneas and TEM microscopy further confirmed the similar patterns of the collagen fibrils in the decellularized, compared to the native corneas. This pilot study showed our method is effective in decellularizing porcine corneas, with a very high amount of DNA being removed, while the GAGs being preserved to an acceptable extent, and the structure and pattern of the collagen fibrils maintained.

• Breder, Sigurd; Villard, Christina; Eide, Emma; Wang, Benny; Engesæter, Lise Katrine & Reims, Henrik Mikael [Vis alle 15 forfattere av denne artikkelen] (2025). A retrospective evaluation of preemptive liver transplantation for bile duct dysplasia in primary sclerosing cholangitis: Balancing risks and benefits. JHEP Reports. 7(12), s. 1–11. doi: 10.1016/j.jhepr.2025.101598. Fulltekst i vitenarkiv Vis sammendrag

  Background & Aims Liver transplantation (LT) to prevent cholangiocarcinoma (CCA) in individuals with primary sclerosing cholangitis (PSC) and bile duct dysplasia was introduced in Norway and Sweden in the early 2000s. We aimed to evaluate this practice to potentially improve future selection of candidates for LT. Methods We conducted a retrospective study of 512 adults with PSC who underwent first-time LT between 2000–2021 at Oslo and Karolinska University Hospitals. Pre-LT findings in bile duct brush cytology and/or biopsy of low-grade dysplasia (LGD) and high-grade dysplasia (HGD) were compared with histological findings in the explanted livers and survival rates were assessed. Results Bile duct dysplasia, low-grade (LGD) or high-grade (HGD), was the primary LT indication in 17% (88/512). Among individuals transplanted for LGD, only 10% (3/29) had HGD or CCA in the explant, compared to 48% (28/59) in the HGD group. No neoplasia was found in 42% (12/29) of LGD and 24% (14/59) of HGD cases, meaning nearly one-third of patients transplanted for suspected bile duct dysplasia had no histological evidence of neoplasia in the explant. Five-year post-transplant survival according to the explant histology was 95% for no neoplasia, 89% for LGD, 85% for HGD, decreasing to 33% in those with CCA in the explant. Conclusions While favorable survival in confirmed dysplasia supports the role of preemptive LT, the absence of neoplasia in a substantial proportion of explants, particularly in suspected LGD, calls for a cautious, individualized approach. LT appears more clearly justified in accurately diagnosed HGD, given its strong association with early malignancy and the poor prognosis of advanced CCA. Impact and implications Individuals with primary sclerosing cholangitis (PSC) are at increased risk of developing bile duct cancer. In precancerous stages (bile duct dysplasia), liver transplantation (LT) may prevent progression to advanced, incurable cancer. In our evaluation of 512 patients with PSC who underwent LT, we found that the low diagnostic accuracy and unpredictable detection of mild dysplasia support a cautious, individualized approach to LT in precancerous stages of PSC, while more advanced dysplasia remains a valid indication for LT.

• Benimam, Mohamed M.; Meas-Yedid, Vannary; Mukherjee, Suvadip; Frafjord, Astri; Corthay, Alexandre Benoit & Lagache, Thibault [Vis alle 7 forfattere av denne artikkelen] (2025). Statistical analysis of spatial patterns in tumor microenvironment images. Nature Communications. 16(1), s. 1–20. doi: 10.1038/s41467-025-57943-y. Fulltekst i vitenarkiv Vis sammendrag

  Advances in tissue labeling, imaging, and automated cell identification now enable the visualization of immune cell types in human tumors. However, a framework for analyzing spatial patterns within the tumor microenvironment (TME) is still lacking. To address this, we develop Spatiopath, a null-hypothesis framework that distinguishes statistically significant immune cell associations from random distributions. Using embedding functions to map cell contours and tumor regions, Spatiopath extends Ripley’s K function to analyze both cell-cell and cell-tumor interactions. We validate the method with synthetic simulations and apply it to multi-color images of lung tumor sections, revealing significant spatial patterns such as mast cells accumulating near T cells and the tumor epithelium. These patterns highlight differences in spatial organization, with mast cells clustering near the epithelium and T cells positioned farther away. Spatiopath enables a better understanding of immune responses and may help identify biomarkers for patient outcomes.

• Vincze, Orsolya; Minias, Piotr; Corthay, Alexandre Benoit; Colchero, Fernando; Lemaître, Jean-François & Maille, Louise [Vis alle 19 forfattere av denne artikkelen] (2025). Immunological surveillance against cancer across mammals. Nature Communications. 16(1), s. 1–12. doi: 10.1038/s41467-025-65286-x. Fulltekst i vitenarkiv Vis sammendrag

  Contrary to expectations based on their higher cell numbers, larger and longer-lived species do not face dramatically increased risk of cancer. This strongly suggests that evolution has fashioned natural cancer resistance mechanisms, yet our knowledge remains limited on what these mechanisms might be. The cancer immunological surveillance hypothesis, proposed by Burnet and Thomas in the 1950s, highlights immunity as a key factor determining species-specific cancer resistance. Here we address the original, evolutionary interpretation of this hypothesis by investigating the relationship between cancer mortality risk and markers of efficient antigen presentation. Our results show that the expansion of the MHC class I gene complex, as well as increased selection for diversity at these genes is associated with sharply decreasing cancer mortality risk across mammals. This suggests that the efficient presentation of diverse peptides in somatic cells is important for cancer suppression across mammals, providing pioneering evidence that supports the cancer immunosurveillance hypothesis across species.

• Nøvik, Steffen; Hirayama-Shoji, Kayoko; Combriat, Thomas; Sakalys, Domantas; Aashamar, Erik & Louch, William E. [Vis alle 9 forfattere av denne artikkelen] (2025). Bioimpedance and electrophysiology measurements of engineered heart tissues outside the culture medium. Biosensors and Bioelectronics. ISSN 0956-5663. 287, s. 117634–117634. doi: 10.1016/j.bios.2025.117634. Fulltekst i vitenarkiv
• Pabst, Oliver; Schülke, Christin; Balasingham, Ilangko; Krauss, Stefan Johannes Karl; Glover, Joel Clinton & Martinsen, Ørjan Grøttem (2025). Recording and modeling of pinched hysteresis loops, the fingerprint of a memristor, in neurons. Scientific Reports. 15. doi: 10.1038/s41598-025-21035-0. Fulltekst i vitenarkiv Vis sammendrag

  A variant of the Hodgkin-Huxley model has been proposed in which time-varying Na+ and K+ ion conductances are replaced by memristors, based on the proposal that ion channels are memristors. This hypothesis predicts that current-voltage plots of neurons subjected to sinusoidal stimulation should exhibit a pinched hysteresis loop, the fingerprint of a memristor. We tested this using whole-cell patch clamp recordings from human neurons derived from neural progenitor cells and observed pinched hysteresis loops in 16% of all recorded neurons. Recordings with current clamp and voltage clamp with a holding potential of 0 mV yielded a higher success rate than voltage clamp recordings with a holding potential of around − 60 mV. In addition, more neurons exhibited pinched hysteresis loops when the applied voltage or current amplitude was high, and the frequency was low. The recording of pinched hysteresis loops in neurons gives evidence that these contain memristors and this is the first time to be shown experimentally. This is not just an indication that the memristor-based Hodgkin-Huxley model is valid; it also demonstrates that models of neurons based on memristors actually resemble nature. We then subjected simulated neurons expressing Hodgkin-Huxley voltage-gated Na+ and K+ channels to sinusoidal membrane potential oscillations and found that the presence of pinched hysteresis loops depended strongly on the density of voltage-gated K+ channels and on the membrane capacitance but not on the presence of voltage-gated Na+ channels. Because Na+ channels are expected to be largely inactivated in neurons at a holding potential of 0 mV, these findings together suggest that it is the presence of voltage-gated K+ channels that is critical for the observed memristive behavior.

• Ho, Richard David Jun-Geet; Mossige, Joachim; Ponomartcev, Sergei; Natalia, Smirnova,; Sunny, Dai, Keqing & Hu, Xian [Vis alle 9 forfattere av denne artikkelen] (2025). [2509.08929] Spontaneous elongation of 3D gastruloids from local cell polarity alignment. arXiv. doi: https:/arxiv.org/abs/2509.08929. Fulltekst i vitenarkiv Vis sammendrag

  Gastruloids are 3D stem cell aggregate models for early embryogenesis that provide a unique platform to study how collective cell dynamics drive tissue symmetry breaking and axial elongation. Using 3D light sheet imaging, we show that a pulse of Chiron, a Wnt activator, induces coherent alignment of cell polarity during elongation. While nuclear elongation occurs with or without treatment, only Chiron-treated gastruloids exhibit quasi-long-range alignment of nuclear axes, linking cell polarity coherence to tissue-scale remodeling. A minimal physical model of polarized cells, incorporating alignment-dependent torques and polarity-mediated adhesion, reproduces symmetry breaking and elongation, demonstrating that local cell polarity alignment alone can drive tissue-scale convergence-extension flows.

• Guttorm, Sander Johannes Thorbjørnsen; Wilson, Steven Ray Haakon; Amundsen, Erik Koldberg; Rootwelt, Helge & Elgstøen, Katja B. Prestø (2025). Scheduled data-dependent acquisition MS provides enhanced identification and sensitivity in clinical lipidomics. Analytica Chimica Acta. ISSN 0003-2670. 1371. doi: 10.1016/j.aca.2025.344426. Fulltekst i vitenarkiv Vis sammendrag

  Background Lipidomics can provide critical insight into metabolic changes in health and disease, but faces challenges in sensitivity, lipid coverage, and annotation accuracy. To address these limitations, we optimized a liquid chromatography–mass spectrometry (LC-MS) method combining scheduled data-dependent acquisition (SDDA) and C30 column-based separations, aimed at improving global lipidomics for clinical diagnostics. Results Compared to conventional DDA and Intelligent Data Acquisition (AcquireX), SDDA demonstrated a 2-fold increase in number of lipids annotated, with a 2-fold higher annotation confidence (Grade A and B) of those lipids compared to DDA. The repeatability and analytical robustness of the method were thoroughly evaluated across different clinical blood matrices, i.e. serum, EDTA-plasma, and dried blood spots (DBS). Serum provided the highest repeatability and lipid coverage, with more than 2000 lipid species annotated. A proof-of-concept study assessing postprandial lipidomic changes in response to intake of a long-chain triglyceride fat emulsion was used to demonstrate the method's applicability in clinical lipidomics. The method detected significant changes in the levels of various lipids, including triacylglycerols, diacylglycerols, bile acids, phosphatidylethanolamines, and lyso-phosphatidylethanolamines, following lipid ingestion. Significance and novelty The optimized lipidomics method (C30-SDDA) enhances lipid coverage and annotation confidence, proving valuable for studying metabolic alterations and biomarker discovery using blood matrices. These findings underscore the clinical potential of this method for advancing diagnostics and personalized medicine.

• Delon, Ludivine; Busek, Mathias; Menezes, Pedro Duarte; Gadegaard, Nikolaj; Stokowiec, Justyna & Golovin, Alexey [Vis alle 10 forfattere av denne artikkelen] (2025). Placental Syncytium-on-Chip (PSoC)–Comparison of Forskolin or Mechanical Induced-Syncytialization. Advanced Healthcare Materials. ISSN 2192-2640. doi: 10.1002/adhm.202404462. Fulltekst i vitenarkiv Vis sammendrag

  The placenta is a key embryonic structure that separates maternal and fetal blood systems. The barrier function of the human placenta is performed by villous trophoblasts, i.e. undifferentiated cytotrophoblasts and differentiated syncytiotrophoblats, whose maturation and function are influenced by wall shear stress (WSS) from the maternal blood circulation. Most in vitro placenta models rely on cyclic adenosine monophosphate inducer forskolin (FSK) to establish a placental syncytium. Here a trophoblastic BeWo cell line is used to systematically compare the effect of FSK treatment in static culture with WSS stimulation in a pumpless, recirculating organ-on-chip. It is shown that BeWo cells undergo a similar differentiation under WSS exposure to FSK treatment. A WSS of 0.1 dyn cm−2 leads to cell fusion, polarization, barrier functions, human chorionic gonadotropin (β-hCG) secretion, and increased expression of key transporters. Moreover, WSS induces favorable changes in the levels of FMS-like tyrosine kinase-1 (FLT-1) and Placental Growth Factor (PlGF) suggesting the development of a physiologically relevant placental syncytium-on-chip (PSoC) without the need for FSK. The platform is further expanded to a syncytiotrophoblast/endothelial co-culture showing physiological vascular functions under WSS. The forskolin-free PSoC presented here represents the first pumpless recirculating and scalable platform for physiological placental studies and drug testing.

• Shoji, Junya; Davis, Richard P.; Mummery, Christine L. & Krauss, Stefan Johannes Karl (2025). Global Literature Analysis of Tumor Organoid and Tumor-on-Chip Research. Cancers. 17(1), s. 1–26. doi: 10.3390/cancers17010108. Fulltekst i vitenarkiv Vis sammendrag

  Background: Tumor organoid and tumor-on-chip (ToC) platforms replicate aspects of the anatomical and physiological states of tumors. They, therefore, serve as models for investigating tumor microenvironments, metastasis, and immune interactions, especially for precision drug testing. To map the changing research diversity and focus in this field, we performed a quality-controlled text analysis of categorized academic publications and clinical studies. Methods: Previously, we collected metadata of academic publications on organoids or organ-on-chip platforms from PubMed, Web of Science, Scopus, EMBASE, and bioRxiv, published between January 2011 and June 2023. Here, we selected documents from this metadata corpus that were computationally determined as relevant to tumor research and analyzed them using an in-house text analysis algorithm. Additionally, we collected and analyzed metadata from ClinicalTrials.gov of clinical studies related to tumor organoids or ToC as of March 2023. Results and Discussion: From 3551 academic publications and 139 clinical trials, we identified 55 and 24 tumor classes modeled as tumor organoids and ToC models, respectively. The research was particularly active in neural and hepatic/pancreatic tumor organoids, as well as gastrointestinal, neural, and reproductive ToC models. Comparative analysis with cancer statistics showed that lung, lymphatic, and cervical tumors were under-represented in tumor organoid research. Our findings also illustrate varied research topics, including tumor physiology, therapeutic approaches, immune cell involvement, and analytical techniques. Mapping the research geographically highlighted the focus on colorectal cancer research in the Netherlands, though overall the specific research focus of countries did not reflect regional cancer prevalence. These insights not only map the current research landscape but also indicate potential new directions in tumor model research.

• Haaker, Maya W.; Chang, Jung-Chin; Chung, Brian K.; Pieper, Tobias S.; Noé, Falko & Wang, Tongtong [Vis alle 13 forfattere av denne artikkelen] (2025). Cellular Crosstalk Promotes Hepatic Progenitor Cell Proliferation and Stellate Cell Activation in 3D Co-culture. Cellular and Molecular Gastroenterology and Hepatology (CMGH). 19(5). doi: 10.1016/j.jcmgh.2025.101472. Fulltekst i vitenarkiv Vis sammendrag

  Background & Aims Following liver damage, ductular reaction often coincides with liver fibrosis. Proliferation of hepatic progenitor cells is observed in ductular reaction, whereas activated hepatic stellate cells (HSCs) are the main drivers of liver fibrosis. These observations may suggest a functional interaction between these 2 cell types. Here, we report on an in vitro co-culture system to examine these interactions and validate their co-expression in human liver explants. Methods In a 3D organoid co-culture system, we combined freshly isolated quiescent mouse HSCs and fluorescently labeled progenitor cells (undifferentiated intrahepatic cholangiocyte organoids), permitting real-time observation of cell morphology and behavior. After 7 days, cells were sorted based on the fluorescent label and analyzed for changes in gene expression. Results In the 3D co-culture system, the proliferation of progenitor cells is enhanced, and HSCs are activated, recapitulating the cellular events observed in the patient liver. Both effects in 3D co-culture require close contact between the 2 different cell types. HSC activation during 3D co-culture differs from quiescent (3D mono-cultured) HSCs and activated HSCs on plastic (2D mono-culture). Upregulation of a cluster of genes containing Aldh1a2, Cthrc1, and several genes related to frizzled binding/Wnt signaling were exclusively observed in 3D co-cultured HSCs. The localized co-expression of specific genes was confirmed by spatial transcriptomics in human liver explants. Conclusion An in vitro 3D co-culture system provides evidence for direct interactions between HSCs and progenitor cells, which are sufficient to drive responses that are similar to those seen during ductular reaction and fibrosis. This model paves the way for further research into the cellular basis of liver pathology.

• Kogler, Stian; Skottvoll, Frøydis Sved; Hruskova, Helena; Rise, Frode; Aizenshtadt, Aleksandra & Krauss, Stefan Johannes Karl [Vis alle 9 forfattere av denne artikkelen] (2025). Electromembrane Extraction Provides Unprecedented Selectivity for Drugs in Cell Culture Media Used in Organoid and Organ-on-Chip Systems. Analytical Chemistry. ISSN 0003-2700. 97(9), s. 4923–4931. doi: 10.1021/acs.analchem.4c04994. Fulltekst i vitenarkiv Vis sammendrag

  The use of organoids and organ-on-chip technologies as nonanimal methodologies in drug discovery and personalized medicine is rapidly expanding. However, the complexity and small volumes of organoid culture samples present significant analytical challenges, e.g., in drug analysis using liquid chromatography–mass spectrometry (LC–MS). Essentially an electrophoresis across an oil membrane, electromembrane extraction (EME) offers a promising approach for measuring drugs, as it is, for example, compatible with small samples such as organoid and organ-on-chip formats. Given the potential of the technology, there is a need to assess the extraction purity of EME extracts to ensure EME’s compatibility with high-throughput, downstream analysis. This study evaluates the effectiveness of EME for sample cleanup in various common cell culture media used for organoids and organs-on-chips. The media were spiked with 90 small-molecule drugs. Using gel electrophoresis (sodium dodecyl sulfate polyacrylamide gel electrophoresis), high-resolution nuclear magnetic resonance spectroscopy, and LC–MS, we demonstrate that EME provides exhaustive removal of unwanted medium components (proteins, polar molecules, and apolar/neutral molecules) while selectively extracting the spiked small-molecule drugs. The approach was demonstrated with human stem-cell-derived liver organoids, allowing simple detection and monitoring of telltale cytochrome P450 metabolism. Taken together, our observations highlight an unprecedented ability of EME to provide sample cleanup for drug analysis in matrixes compatible with organoids and organ-on-chip technology.

• Bosetti, Chiara; Kampasis, Dionysis; Brinch, Shoshy Alam; Galera-Prat, Albert; Karelou, Maria & Dhakar, Saurabh S. [Vis alle 10 forfattere av denne artikkelen] (2025). Substitutions at the C-8 position of quinazolin-4-ones improve the potency of nicotinamide site binding tankyrase inhibitors. European Journal of Medicinal Chemistry. ISSN 0223-5234. 288. doi: 10.1016/j.ejmech.2025.117397. Fulltekst i vitenarkiv Vis sammendrag

  Human diphtheria toxin-like ADP-ribosyltransferases, PARPs and tankyrases, transfer ADP-ribosyl groups to other macromolecules, thereby controlling various signaling events in cells. They are considered promising drug targets, especially in oncology, and a vast number of inhibitors have already been successfully developed. These inhibitors typically occupy the nicotinamide binding site and extend along the NAD+ binding groove of the catalytic domain. Quinazolin-4-ones have been explored as compelling scaffolds for such inhibitors and we have identified a new position within the catalytic domain that has not been extensively studied yet. In this study, we investigate larger substituents at the C-8 position and, using X-ray crystallography, we demonstrate that nitro- and diol-substituents engage in new interactions with TNKS2, improving both affinity and selectivity. Both diol- and nitro-substituents exhibit intriguing inhibition of TNKS2, with the diol-based compound EXQ-1e displaying a pIC50 of 7.19, while the nitro-based compound EXQ-2d's pIC50 value is 7.86. Both analogues impact and attenuate the tankyrase-controlled WNT/β-catenin signaling with sub-micromolar IC50. When tested against a wider panel of enzymes, the nitro-based compound EXQ-2d displayed high selectivity towards tankyrases, whereas the diol-based compound EXQ-1e also inhibited other PARPs. Compound EXQ-2d displays in vitro cell growth inhibition of the colon cancer cell line COLO 320DM, while compound EXQ-1e displays nonspecific cell toxicity. Collectively, the results offer new insights for inhibitor development targeting tankyrases and PARPs by focusing on the subsite between a mobile active site loop and the canonical nicotinamide binding site.

• Molinaro, Antonio; Engesæter, Lise Katrine; Jorns, Carl; Nordin, Arno; Rasmussen, Allan & Line, Pål Dag [Vis alle 11 forfattere av denne artikkelen] (2025). Outcome of Liver Retransplantation in Patients With Primary Sclerosing Cholangitis. Liver international (Print). ISSN 1478-3223. 45(1). doi: 10.1111/liv.16214. Fulltekst i vitenarkiv Vis sammendrag

  Background and Aims Primary sclerosing cholangitis (PSC) is among the most common indications for liver transplantation in the Nordic countries and with an increasing trend in Europe and North America. Due to post-transplant complications and high prevalence of disease recurrence this group is at risk of requiring retransplantation (re-LTX). Results from re-LTX for PSC are not extensively studied and there is a lack of knowledge regarding prognosis after re-LTX in this population. Methods Graft and patient survival after re-LTX for patients with PSC and a comparable comparison group from the Nordic liver transplant registry were analysed. One-hundred and eighty-five patients with PSC and 208 patients in the comparison group were included. Results The graft and patient survival were better for patients with PSC compared to the comparison group (p < 0.001). Re-LTX for recurrence of PSC (rPSC) compared to other aetiologies had similar and better outcomes for graft and patient survival (p = 0.093 and p = 0.023, respectively). Moreover, re-LTX for rPSC compared to the comparison group had a lower 30-day and 5-year mortality (p < 0.001 and p = 0.041, respectively). Conclusion Outcomes after retransplantation for PSC were similar or better compared to the comparison group. Retransplantation represents a treatment option with the potential for excellent outcomes in patients with PSC and should be considered in transplanted PSC patients with graft failure.

• Dowlatshah, Samira; Hay, Anne Oldeide; Noreng, Line & Hansen, Frederik Andre (2025). A practical tutorial for optimizing electromembrane extraction methods by response surface methodology. Advances in Sample Preparation. 14. doi: 10.1016/j.sampre.2025.100170. Fulltekst i vitenarkiv Vis sammendrag

  Microextraction techniques, such as electromembrane extraction (EME), have greatly advanced analytical chemistry by providing efficient, cost-effective, and eco-friendly sample preparation methods. EME is especially promising for ionizable analytes, with its success relying on optimizing multiple experimental variables. Traditionally, optimization has employed a one-variable-at-a-time (OVAT) approach, which is time-consuming and may overlooks variable interactions. This tutorial introduces response surface methodology (RSM) as a superior alternative for optimizing EME methods. RSM allows for the simultaneous variation of multiple factors, offering a comprehensive understanding of their effects and interactions with fewer experiments. This tutorial covers the fundamental principles of EME, essential experimental parameters, and the application of RSM for method optimization. It includes guidance on software selection, design choice, factor settings, response definition, and the optimization of multiple responses. Practical steps for conducting experiments, analyzing data, and interpreting models are detailed, with real-life examples illustrating the process. The tutorial aims to make RSM accessible to both novice and moderately experienced users, promoting its broader application in analytical chemistry. By simplifying the complex optimization process, this tutorial supports the development of robust, efficient, and green EME methods.

• Nikitina, Darja; Lukosevicius, Rokas; Tilinde, Deimante; Muskieta, Tomas; Hov, Johannes Espolin Roksund & Melum, Espen [Vis alle 11 forfattere av denne artikkelen] (2024). Cell-Free Microbial DNA Analysis: Effects of Blood Plasma and Serum Quantity, Biobanking Protocols, and Isolation Kits. Biopreservation and Biobanking. ISSN 1947-5535. 22(4), s. 363–372. doi: 10.1089/bio.2023.0048. Fulltekst i vitenarkiv
• Combriat, Thomas Michel Daniel; Dysthe, Dag Kristian & Flekkøy, Eirik Grude (2024). Cavitation dynamics in creeping flow. Journal of Fluid Mechanics. ISSN 0022-1120. 999. doi: 10.1017/jfm.2024.937. Fulltekst i vitenarkiv Vis sammendrag

  We investigate the heterogeneous cavitation phenomenon in water when a spherical surface is abruptly separated from a nearby flat substrate, at a distance of approximately 10 nm. By tracking the surface separation using Newton ring positions, and capturing the bubble evolution with a high-speed camera on a microscope, we compare our experimental findings with hydrodynamic predictions at low Reynolds numbers. Upon upward movement of the spherical surface, the resulting bubble develops branched fingers through the Saffman–Taylor instability. Simultaneously, negative liquid pressures in the range ∼ 10 atm are observed. These large tension values occasionally lead to secondary nucleation events. The bubble sizes satisfy a predicted Family–Vicsek scaling law where the bubble area is proportional to the inverse bubble lifetime. The fact that creeping flow cavitation bubbles are more short-lived the larger they are separates them from bubbles that are governed by inertial dynamics.

• Cunha, André; Schülke, Christin; Mesri, Alireza; Ruud, Simen Kristoffer; Aizenshtadt, Aleksandra & Ferrari, Giorgio [Vis alle 16 forfattere av denne artikkelen] (2024). Development of a Smart Wireless Multisensor Platform for an Optogenetic Brain Implant. Sensors. 24(2). doi: 10.3390/s24020575. Fulltekst i vitenarkiv Vis sammendrag

  Implantable cell replacement therapies promise to completely restore the function of neural structures, possibly changing how we currently perceive the onset of neurodegenerative diseases. One of the major clinical hurdles for the routine implementation of stem cell therapies is poor cell retention and survival, demanding the need to better understand these mechanisms while providing precise and scalable approaches to monitor these cell-based therapies in both pre-clinical and clinical scenarios. This poses significant multidisciplinary challenges regarding planning, defining the methodology and requirements, prototyping and different stages of testing. Aiming toward an optogenetic neural stem cell implant controlled by a smart wireless electronic frontend, we show how an iterative development methodology coupled with a modular design philosophy can mitigate some of these challenges. In this study, we present a miniaturized, wireless-controlled, modular multisensor platform with fully interfaced electronics featuring three different modules: an impedance analyzer, a potentiostat and an optical stimulator. We show the application of the platform for electrical impedance spectroscopy-based cell monitoring, optical stimulation to induce dopamine release from optogenetically modified neurons and a potentiostat for cyclic voltammetry and amperometric detection of dopamine release. The multisensor platform is designed to be used as an opto-electric headstage for future in vivo animal experiments.

• Kogler, Stian; Pedersen, Gustav Mathingsdal; Martínez-Ramírez, Felipe; Aizenshtadt, Aleksandra; Busek, Mathias & Krauss, Stefan Johannes Karl [Vis alle 8 forfattere av denne artikkelen] (2024). An FDA-Validated, Self-Cleaning Liquid Chromatography–Mass Spectrometry System for Determining Small-Molecule Drugs and Metabolites in Organoid/Organ-on-Chip Medium. Analytical Chemistry. ISSN 0003-2700. 96(29), s. 12129–12138. doi: 10.1021/acs.analchem.4c02246. Fulltekst i vitenarkiv Vis sammendrag

  As organoids and organ-on-chip (OoC) systems move toward preclinical and clinical applications, there is an increased need for method validation. Using a liquid chromatography–mass spectrometry (LC–MS)-based approach, we developed a method for measuring small-molecule drugs and metabolites in the cell medium directly sampled from liver organoids/OoC systems. The LC–MS setup was coupled to an automatic filtration and filter flush system with online solid-phase extraction (SPE), allowing for robust and automated sample cleanup/analysis. For the matrix, rich in, e.g., protein, salts, and amino acids, no preinjection sample preparation steps (protein precipitation, SPE, etc.) were necessary. The approach was demonstrated with tolbutamide and its liver metabolite, 4-hydroxytolbutamide (4HT). The method was validated for analysis of cell media of human stem cell-derived liver organoids cultured in static conditions and on a microfluidic platform according to Food and Drug Administration (FDA) guidelines with regards to selectivity, matrix effects, accuracy, precision, etc. The system allows for hundreds of injections without replacing chromatography hardware. In summary, drug/metabolite analysis of organoids/OoCs can be performed robustly with minimal sample preparation.

• Menezes, Pedro Duarte; Hunter, Alisha; Dickson, Thomas; Hecht, Soren; Kumar, Charchit & Busek, Mathias [Vis alle 8 forfattere av denne artikkelen] (2024). Scalable, Transparent, and Micro: 3D-Printed Rapid Tooling for Injection Molded Microfluidics. Advanced Engineering Materials. ISSN 1438-1656. 26(20). doi: 10.1002/adem.202400276. Fulltekst i vitenarkiv
• Hrušková, Helena; Olsen, Christine; Řemínek, Roman; Wang, Chencheng; Aizenshtadt, Aleksandra & Krauss, Stefan Johannes Karl [Vis alle 10 forfattere av denne artikkelen] (2024). Preparative agarose gel electrophoresis for reducing matrix interferences of organoid cell medium prior to LC-MS analysis of insulin. Journal of Chromatography A. ISSN 0021-9673. 1717. doi: 10.1016/j.chroma.2024.464669. Fulltekst i vitenarkiv Vis sammendrag

  Organoids are 3D cell cultures with microanatomies mimicking aspects of real organs, useful for e.g. animal-free studies of development, disease, and drug discovery. The cell medium of organoid models of Langerhans islets, regulating blood glucose levels by insulin secretion, can be analyzed by liquid chromatography-mass spectrometry (LC-MS). However, organoid medium complexity is a major challenge, as matrix interferences can reduce sensitivity and selectivity, even with optimized LC-MS conditions. By applying preparative agarose gel electrophoresis-electrodialysis (PGE-ED), we were able to decrease the cell medium background signal, allowing for reduced interferences affecting LC-MS analysis of human insulin.

• Wilhelmsen, Ingrid; Combriat, Thomas Michel Daniel; Dalmao-Fernandez, Andrea; Stokowiec, Justyna; Wang, Chencheng & Olsen, Petter Angell [Vis alle 10 forfattere av denne artikkelen] (2024). The effects of TGF-β-induced activation and starvation of vitamin A and palmitic acid on human stem cell-derived hepatic stellate cells. Stem Cell Research & Therapy. 15(223). doi: 10.1186/s13287-024-03852-8. Fulltekst i vitenarkiv Vis sammendrag

  Background Hepatic stellate cells (HSC) have numerous critical roles in liver function and homeostasis, while they are also known for their importance during liver injury and fibrosis. There is therefore a need for relevant in vitro human HSC models to fill current knowledge gaps. In particular, the roles of vitamin A (VA), lipid droplets (LDs), and energy metabolism in human HSC activation are poorly understood. Methods In this study, human pluripotent stem cell-derived HSCs (scHSCs), benchmarked to human primary HSC, were exposed to 48-hour starvation of retinol (ROL) and palmitic acid (PA) in the presence or absence of the potent HSC activator TGF-β. The interventions were studied by an extensive set of phenotypic and functional analyses, including transcriptomic analysis, measurement of activation-related proteins and cytokines, VA- and LD storage, and cell energy metabolism. Results The results show that though the starvation of ROL and PA alone did not induce scHSC activation, the starvation amplified the TGF-β-induced activation-related transcriptome. However, TGF-β-induced activation alone did not lead to a reduction in VA or LD stores. Additionally, reduced glycolysis and increased mitochondrial fission were observed in response to TGF-β. Conclusions scHSCs are robust models for activation studies. The loss of VA and LDs is not sufficient for scHSC activation in vitro, but may amplify the TGF-β-induced activation response. Collectively, our work provides an extensive framework for studying human HSCs in healthy and diseased conditions.

• Combriat, Thomas Michel Daniel; Olsen, Petter Angell; Låstad, Silja Borring; Malthe-Sørenssen, Anders; Krauss, Stefan Johannes Karl & Dysthe, Dag Kristian (2024). Acoustic Wave-Induced Stroboscopic Optical Mechanotyping of Adherent Cells. Advanced Science. 11(16). doi: 10.1002/advs.202307929. Fulltekst i vitenarkiv Vis sammendrag

  In this study, a novel, high content technique using a cylindrical acoustic transducer, stroboscopic fast imaging, and homodyne detection to recover the mechanical properties (dynamic shear modulus) of living adherent cells at low ultrasonic frequencies is presented. By analyzing the micro-oscillations of cells, whole populations are simultaneously mechanotyped with sub-cellular resolution. The technique can be combined with standard fluorescence imaging allowing to further cross-correlate biological and mechanical information. The potential of the technique is demonstrated by mechanotyping co-cultures of different cell types with significantly different mechanical properties.

• Aizenshtadt, Aleksandra; Wang, Chencheng; Abadpour, Shadab; Menezes, Pedro Duarte; Wilhelmsen, Ingrid & Dalmao-Fernandez, Andrea [Vis alle 15 forfattere av denne artikkelen] (2024). Pump-Less, Recirculating Organ-on-Chip (rOoC) Platform to Model the Metabolic Crosstalk between Islets and Liver. Advanced Healthcare Materials. ISSN 2192-2640. 13(13). doi: 10.1002/adhm.202303785. Fulltekst i vitenarkiv Vis sammendrag

  Type 2 diabetes mellitus (T2DM), obesity, and metabolic dysfunction-associated steatotic liver disease (MASLD) are epidemiologically correlated disorders with a worldwide growing prevalence. While the mechanisms leading to the onset and development of these conditions are not fully understood, predictive tissue representations for studying the coordinated interactions between central organs that regulate energy metabolism, particularly the liver and pancreatic islets, are needed. Here, a dual pump-less recirculating organ-on-chip platform that combines human pluripotent stem cell (sc)-derived sc-liver and sc-islet organoids is presented. The platform reproduces key aspects of the metabolic cross-talk between both organs, including glucose levels and selected hormones, and supports the viability and functionality of both sc-islet and sc-liver organoids while preserving a reduced release of pro-inflammatory cytokines. In a model of metabolic disruption in response to treatment with high lipids and fructose, sc-liver organoids exhibit hallmarks of steatosis and insulin resistance, while sc-islets produce pro-inflammatory cytokines on-chip. Finally, the platform reproduces known effects of anti-diabetic drugs on-chip. Taken together, the platform provides a basis for functional studies of obesity, T2DM, and MASLD on-chip, as well as for testing potential therapeutic interventions.

• Liang, Xiao; Chen, Anbin; Kianian, Atefeh; Kristiansen, Cecilie Katrin; Yangzom, Tsering Yangzom Tsering & Palmer, Jessica Furriol [Vis alle 13 forfattere av denne artikkelen] (2024). Activation of Neurotoxic Astrocytes Due to Mitochondrial Dysfunction Triggered by POLG Mutation. International Journal of Biological Sciences. 20(8), s. 2860–2880. doi: 10.7150/ijbs.93445. Fulltekst i vitenarkiv Vis sammendrag

  Mitochondrial diseases are associated with neuronal death and mtDNA depletion. Astrocytes respond to injury or stimuli and damage to the central nervous system. Neurodegeneration can cause astrocytes to activate and acquire toxic functions that induce neuronal death. However, astrocyte activation and its impact on neuronal homeostasis in mitochondrial disease remain to be explored. Using patient cells carrying POLG mutations, we generated iPSCs and then differentiated these into astrocytes. POLG astrocytes exhibited mitochondrial dysfunction including loss of mitochondrial membrane potential, energy failure, loss of complex I and IV, disturbed NAD+/NADH metabolism, and mtDNA depletion. Further, POLG derived astrocytes presented an A1-like reactive phenotype with increased proliferation, invasion, upregulation of pathways involved in response to stimulus, immune system process, cell proliferation and cell killing. Under direct and indirect co-culture with neurons, POLG astrocytes manifested a toxic effect leading to the death of neurons. We demonstrate that mitochondrial dysfunction caused by POLG mutations leads not only to intrinsic defects in energy metabolism affecting both neurons and astrocytes, but also to neurotoxic damage driven by astrocytes. These findings reveal a novel role for dysfunctional astrocytes that contribute to the pathogenesis of POLG diseases.

• Wang, Chencheng; Abadpour, Shadab; Aizenshtadt, Aleksandra; Dalmao-Fernandez, Andrea; Høyem, Merete & Wilhelmsen, Ingrid [Vis alle 13 forfattere av denne artikkelen] (2024). Cell identity dynamics and insight into insulin secretagogues when employing stem cell-derived islets for disease modeling. Frontiers in Bioengineering and Biotechnology. 12. doi: 10.3389/fbioe.2024.1392575. Fulltekst i vitenarkiv Vis sammendrag

  Stem cell-derived islets (SC-islets) are not only an unlimited source for cell-based therapy of type 1 diabetes but have also emerged as an attractive material for modeling diabetes and conducting screening for treatment options. Prior to SC-islets becoming the established standard for disease modeling and drug development, it is essential to understand their response to various nutrient sources in vitro. This study demonstrates an enhanced efficiency of pancreatic endocrine cell differentiation through the incorporation of WNT signaling inhibition following the definitive endoderm stage. We have identified a tri-hormonal cell population within SC-islets, which undergoes reduction concurrent with the emergence of elevated numbers of glucagon-positive cells during extended in vitro culture. Over a 6-week period of in vitro culture, the SC-islets consistently demonstrated robust insulin secretion in response to glucose stimulation. Moreover, they manifested diverse reactivity patterns when exposed to distinct nutrient sources and exhibited deviant glycolytic metabolic characteristics in comparison to human primary islets. Although the SC-islets demonstrated an aberrant glucose metabolism trafficking, the evaluation of a potential antidiabetic drug, pyruvate kinase agonist known as TEPP46, significantly improved in vitro insulin secretion of SC-islets. Overall, this study provided cell identity dynamics investigation of SC-islets during prolonged culturing in vitro, and insights into insulin secretagogues. Associated advantages and limitations were discussed when employing SC-islets for disease modeling.

• Mathisen, Andreas Frøslev; Legøy, Thomas Aga; Larsen, Ulrik; Unger, Lucas; Abadpour, Shadab & Paulo, Joao A. [Vis alle 9 forfattere av denne artikkelen] (2024). The age-dependent regulation of pancreatic islet landscape is fueled by a HNF1a-immune signaling loop. Mechanisms of Ageing and Development. ISSN 0047-6374. 220. doi: 10.1016/j.mad.2024.111951. Fulltekst i vitenarkiv Vis sammendrag

  Animal longevity is a function of global vital organ functionality and, consequently, a complex polygenic trait. Yet, monogenic regulators controlling overall or organ-specific ageing exist, owing their conservation to their function in growth and development. Here, by using pathway analysis combined with wet-biology methods on several dynamic timelines, we identified Hnf1a as a novel master regulator of the maturation and ageing in the adult pancreatic islet during the first year of life. Conditional transgenic mice bearing suboptimal levels of this transcription factor in the pancreatic islets displayed age-dependent changes, with a profile echoing precocious maturation. Additionally, the comparative pathway analysis revealed a link between Hnf1a age-dependent regulation and immune signaling, which was confirmed in the ageing timeline of an overly immunodeficient mouse model. Last, the global proteome analysis of human islets spanning three decades of life largely backed the age-specific regulation observed in mice. Collectively, our results suggest a novel role of Hnf1a as a monogenic regulator of the maturation and ageing process in the pancreatic islet via a direct or indirect regulatory loop with immune signaling.

• Wold, Christian Winther; Christopoulos, Panagiotis; Arias, Maykel; Dzovor, Deborah Elikplim; Øynebråten, Inger & Corthay, Alexandre Benoit [Vis alle 7 forfattere av denne artikkelen] (2024). Fungal polysaccharides from Inonotus obliquus are agonists for Toll-like receptors and induce macrophage anti-cancer activity. Communications Biology. 7. doi: 10.1038/s42003-024-05853-y. Fulltekst i vitenarkiv Vis sammendrag

  Fungal polysaccharides can exert immunomodulating activity by triggering pattern recognition receptors (PRRs) on innate immune cells such as macrophages. Here, we evaluate six polysaccharides isolated from the medicinal fungus Inonotus obliquus for their ability to activate mouse and human macrophages. We identify two water-soluble polysaccharides, AcF1 and AcF3, being able to trigger several critical antitumor functions of macrophages. AcF1 and AcF3 activate macrophages to secrete nitric oxide and the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Combined with interferon-γ, the fungal polysaccharides trigger high production of IL-12p70, a central cytokine for antitumor immunity, and induce macrophage-mediated inhibition of cancer cell growth in vitro and in vivo. AcF1 and AcF3 are strong agonists of the PRRs Toll-like receptor 2 (TLR2) and TLR4, and weak agonists of Dectin-1. In comparison, two prototypical particulate β-glucans, one isolated from I. obliquus and one from Saccharomyces cerevisiae (zymosan), are agonists for Dectin-1 but not TLR2 or TLR4, and are unable to trigger anti-cancer functions of macrophages. We conclude that the water-soluble polysaccharides AcF1 and AcF3 from I. obliquus have a strong potential for cancer immunotherapy by triggering multiple PRRs and by inducing potent anti-cancer activity of macrophages.

• Wang, Chencheng; Abadpour, Shadab; Olsen, Petter Angell; Wang, Daxin; Stokowiec, Justyna & Chera, Simona [Vis alle 11 forfattere av denne artikkelen] (2024). Glucose Concentration in Regulating Induced Pluripotent Stem Cells Differentiation Toward Insulin-Producing Cells. Transplant International. ISSN 0934-0874. 37. doi: 10.3389/ti.2024.11900. Fulltekst i vitenarkiv Vis sammendrag

  The generation of insulin-producing cells from human-induced pluripotent stem cells holds great potential for diabetes modeling and treatment. However, existing protocols typically involve incubating cells with un-physiologically high concentrations of glucose, which often fail to generate fully functional IPCs. Here, we investigated the influence of high (20 mM) versus low (5.5 mM) glucose concentrations on IPCs differentiation in three hiPSC lines. In two hiPSC lines that were unable to differentiate to IPCs sufficiently, we found that high glucose during differentiation leads to a shortage of NKX6.1+ cells that have co-expression with PDX1 due to insufficient NKX6.1 gene activation, thus further reducing differentiation efficiency. Furthermore, high glucose during differentiation weakened mitochondrial respiration ability. In the third iPSC line, which is IPC differentiation amenable, glucose concentrations did not affect the PDX1/NKX6.1 expression and differentiation efficiency. In addition, glucose-stimulated insulin secretion was only seen in the differentiation under a high glucose condition. These IPCs have higher KATP channel activity and were linked to sufficient ABCC8 gene expression under a high glucose condition. These data suggest high glucose concentration during IPC differentiation is necessary to generate functional IPCs. However, in cell lines that were IPC differentiation unamenable, high glucose could worsen the situation.

• Berishvili, Ekaterine; Piemonti, Lorenzo; Koning, Eelco J. P. de; Lindstedt, Sandra; Scholz, Hanne & Scott, William E. [Vis alle 13 forfattere av denne artikkelen] (2024). ESOT Roadmap for Advanced Therapy Medicinal Products in Transplantation: Navigating Regulatory Challenges to Enhance Access and Care. Transplant International. ISSN 0934-0874. 37. doi: 10.3389/ti.2024.13485. Fulltekst i vitenarkiv Vis sammendrag

  The field of organ transplantation is experiencing a transformative shift with the rise of Advanced Therapy Medicinal Products (ATMPs), which include gene therapies, somatic cell therapies, and tissue-engineered products. These therapies offer new, potentially curative treatments for longstanding medical challenges, impacting numerous patients. However, their adoption is hindered by complex regulatory frameworks, high production costs, and inconsistent access across Europe. The ESOT ATMP Task Force’s position paper analyzes these challenges from research to clinical application, advocating for a coordinated strategy to position Europe as a leader in ATMP development. It proposes specific actions such as streamlining regulatory pathways to accelerate approvals, boosting funding for ATMP research, and creating specialized facilities for development and implementation. The paper also highlights the critical roles of patient engagement and real-world evidence in optimizing clinical and regulatory practices.

• Frank, Anna Katharina; Chung, Brian K.; Novales, Miguel Larraz Lopez De; Engesæter, Lise Katrine; Hoyle, Henry William & Øgaard, Jonas Daniel Sjøberg [Vis alle 15 forfattere av denne artikkelen] (2024). Single-Cell Transcriptomic Profiling of Cholangiocyte Organoids Derived from Bile Ducts of Primary Sclerosing Cholangitis Patients. Digestive Diseases and Sciences. ISSN 0163-2116. 69, s. 3810–3823. doi: 10.1007/s10620-024-08570-y. Fulltekst i vitenarkiv Vis sammendrag

  Background and Aims Primary sclerosing cholangitis (PSC) is a chronic inflammatory liver disorder without effective medical treatment which is characterized by inflammation and fibrotic structures around the bile ducts. Biliary epithelial cells (cholangiocytes) are the target and potential disease drivers in PSC, yet little is known if cholangiocytes from PSC patients differ from non-PSC controls. To characterize cholangiocytes at early rather than end-stage disease, cholangiocyte organoids (COs) were derived from diseased bile ducts of PSC patients and compared to organoids generated from disease controls. Methods Cholangiocytes were obtained during endoscopic retrograde cholangiopancreatography (ERCP) brushing of diseased bile duct areas and expanded as organoids using previously established culture methods. Stable CO lines were analyzed for cell type identity, basic cholangiocyte function, and transcriptomic signature. Results We demonstrate that cholangiocytes, derived from the damaged area within the bile ducts of PSC patients, can be expanded in culture without displaying functional or genetic disease-related features. We further show that COs from patients who later were diagnosed with dysplasia exhibit higher expression of the cancer-associated genes PGC, FXYD2, MIR4435-2HG, and HES1. Conclusions Our results demonstrate that PSC organoids are largely similar to control organoids after culture and highlight the significance of COs as a tool for regenerative medicine approaches as well as their potential for discovering new potential biomarkers for diagnosing cholangiocarcinoma.

• Gramignoli, Roberto; Hofmann, Nicola; Agudo-Barriuso, Marta; Antica, Mariastefania; Flores, Ana I. & Girandon, Lenart [Vis alle 14 forfattere av denne artikkelen] (2024). Expert Revision of Key Elements for Clinical-Grade Production and Qualification of Perinatal Derivatives. Stem Cells Translational Medicine. ISSN 2157-6564. 13(1), s. 14–29. doi: 10.1093/stcltm/szad068. Fulltekst i vitenarkiv Vis sammendrag

  Perinatal derivatives have been proposed as adjunct therapeutic strategies or innovative treatments. Undoubtedly, perinatal derivatives can offer the opportunity and source material to isolate multipotent stem cells, but both maternal- and fetal-derived tissues can be processed and transformed into engineered tissues or advanced biomedical devices, whose potential remains to be fully elucidated. Promising preclinical and clinical results collected so far clearly foresee an escalation of such novel treatments. Market forecasts predict exponential growth in such advanced medicinal products during the next decade, with a pragmatic innovation for medicine into a more advanced biomedical version, enlarging the portfolio for treating a wide range of congenital and acute conditions. However, all these promising and fascinating therapeutic possibilities cannot gain a solid and recognized role in established medical practice without rigid and harmonized manufacturing strategies. The implementation of strategies according to guidelines and directives compiled by Regulatory Agencies, in conformity to (European) Pharmacopoeia and for Good Manufacturing Practice -conforming production of such products, represent critical steps required to translate perinatal technologies into effective therapeutic approaches. During the past 5 years, a panel of European experts and developers, gathered under the umbrella of the COST Sprint Action, supported by the European Cooperation in Science and Technology action, had the opportunity to revise and summarize experience and recommendations for a fruitful and proficient generation of perinatal biomedical products. In order to facilitate the creation and potential commercialization of perinatal bioengineered and advanced pharmaceutical products and technologies, such a collection of data and recommendations is described and discussed here.

• Gilmour, Brian Christopher; Corthay, Alexandre Benoit & Øynebråten, Inger (2024). High production of IL-12 by human dendritic cells stimulated with combinations of pattern-recognition receptor agonists. npj Vaccines. 9:83(1), s. 1–12. doi: 10.1038/s41541-024-00869-1. Fulltekst i vitenarkiv Vis sammendrag

  The cytokine IL-12p70 is crucial for T helper 1 (Th1) polarization and the generation of type 1 immunity required to fight cancer and pathogens. Therefore, strategies to optimize the production of IL-12p70 by human dendritic cells (DCs) may significantly improve the efficacy of vaccines and immunotherapies. However, the rules governing the production of IL-12p70 remain obscure. Here, we stimulated pattern recognition receptors (PRRs) representing five families of PRRs, to evaluate their ability to elicit high production of IL-12p70 by monocyte-derived DCs. We used ten well-characterized agonists and stimulated DCs in vitro with either single agonists or 27 different combinations. We found that poly(I:C), which engages the RNA-sensing PRRs TLR3 and MDA5, and LPS which stimulates TLR4, were the only agonists that could elicit notable IL-12p70 production when used as single ligands. We identified six different combinations of PRR agonists, all containing either the TLR3/MDA5 agonist poly(I:C) or the TLR7/8 agonist R848, that could synergize to elicit high production of IL-12p70 by human DCs. Five of the six combinations also triggered high production of the antiviral and antitumor cytokine IFNβ. Overall, the tested PRR ligands could be divided into three groups depending on whether they triggered production of both IL-12p70 and IFNβ, only one of the two, or neither. Thus, combinations of PRR agonists were found to increase the production of IL-12p70 by human DCs in a synergistic manner, and we identified six PRR agonist combinations that may represent strong adjuvant candidates, in particular for therapeutic cancer vaccines.

• Gregersen, Ida; Kong, Xiang Yi; Kooijman, Sander; Foyn, Håvard; Grannes, Helene & Olsen, Maria Belland [Vis alle 25 forfattere av denne artikkelen] (2024). T cells with increased responsiveness cause obesity in mice without diet intervention. iScience. 27(4). doi: 10.1016/j.isci.2024.109471. Fulltekst i vitenarkiv Vis sammendrag

  Obesity is a complex multicausal disease that can cause morbidity and mortality, and there is need for improved knowledge on the underlying mechanisms. Using a mouse model of increased T cell responsiveness, we show that development of obesity can be driven by immune cells. This was confirmed with bone marrow transplantation and adoptive T cell transfer to several recipient mouse models. Single-cell RNA sequencing and CyTOF analysis showed that the mice display altered composition of circulating T cells and increased T cell activation in visceral adipose tissue, suggesting activated T cells as critical players in the increased fat mass. In this study, we provide evidence that obesity can be driven by immune cell activity and in particular by T cells, which could have broad implications for prevention and treatment of this condition.

• Harrison, Sean Philip; Baumgarten, Saphira Felicitas; Dugarte, Maria Eugenia Chollet; Stavik, Benedicte; Bhattacharya, Anindita & Almaas, Runar [Vis alle 7 forfattere av denne artikkelen] (2024). Parenteral nutrition emulsion inhibits CYP3A4 in an iPSC derived liver organoids testing platform. Journal of Pediatric Gastroenterology and Nutrition - JPGN. ISSN 0277-2116. 78, s. 1047–1058. doi: 10.1002/jpn3.12195. Fulltekst i vitenarkiv Vis sammendrag

  Objectives Parenteral nutrition (PN) is used for patients of varying ages with intestinal failure to supplement calories. Premature newborns with low birth weight are at a high risk for developing PN associated liver disease (PNALD) including steatosis, cholestasis, and gallbladder sludge/stones. To optimize nutrition regimens, models are required to predict PNALD. Methods We have exploited induced pluripotent stem cell derived liver organoids to provide a testing platform for PNALD. Liver organoids mimic the developing liver and contain the different hepatic cell types. The organoids have an early postnatal maturity making them a suitable model for premature newborns. To mimic PN treatment we used medium supplemented with either clinoleic (80% olive oil/20% soybean oil) or intralipid (100% soybean oil) for 7 days. Results Homogenous HNF4a staining was found in all organoids and PN treatments caused accumulation of lipids in hepatocytes. Organoids exhibited a dose dependent decrease in CYP3A4 activity and expression of hepatocyte functional genes. The lipid emulsions did not affect overall organoid viability and glucose levels had no contributory effect to the observed results. Conclusions Liver organoids could be utilized as a potential screening platform for the development of new, less hepatotoxic PN solutions. Both lipid treatments caused hepatic lipid accumulation, a significant decrease in CYP3A4 activity and a decrease in the RNA levels of both CYP3A4 and CYP1A2 in a dose dependent manner. The presence of high glucose had no additive effect, while Clinoleic at high dose, caused significant upregulation of interleukin 6 and TLR4 expression.

• Oldereid, Tine Simensen; Jiang, Xiaojun; Øgaard, Jonas Daniel Sjøberg; Schrumpf, Elisabeth; Bjørnholt, Jørgen & Rasmussen, Henrik [Vis alle 7 forfattere av denne artikkelen] (2023). Microbial exposure during early life regulates development of bile duct inflammation. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 59(2), s. 192–201. doi: 10.1080/00365521.2023.2278423. Fulltekst i vitenarkiv Vis sammendrag

  Objectives The early life microbiome has been linked to inflammatory diseases in adulthood and a role for the microbiome in bile duct inflammation is supported by both human and murine studies. We utilized the NOD.c3c4 mouse model that develops a spontaneous immune-driven biliary disease with a known contribution of the microbiome to evaluate the temporal effects of the early life microbiome. Materials and methods Germ-free (GF) NOD.c3c4 mice were conventionalized into a specific pathogen free environment at birth (conventionally raised, CONV-R) or at weaning (germ-free raised, GF-R) and compared with age and gender-matched GF and conventional (CONV) NOD.c3c4 mice. At 9 weeks of age, liver pathology was assessed by conventional histology and flow cytometry immunophenotyping. Results Neonatal exposure to microbes (CONV-R) increased biliary inflammation to similar levels as regular conventional NOD.c3c4 mice, while delayed exposure to microbes (GF-R) restrained the biliary inflammation. Neutrophil infiltration was increased in all conventionalized mice compared to GF. An immunophenotype in the liver similar to CONV was restored in both CONV-R and GF-R compared to GF mice displaying a proportional increase of B cells and reduction of T cells in the liver. Conclusions Microbial exposure during early life has a temporal impact on biliary tract inflammation in the NOD.c3c4 mouse model suggesting that age-sensitive interaction with commensal microbes have long-lasting effects on biliary immunity that can be of importance for human cholangiopathies.

• Tse, Janson; O’Keefe, Ryan; Rigopolous, Angela; Carli, Annalisa L. E.; Waaler, Jo & Krauss, Stefan Johannes Karl [Vis alle 8 forfattere av denne artikkelen] (2023). A Mouse Model for the Rapid and Binomial Assessment of Putative WNT/β-Catenin Signalling Inhibitors. Biomedicines. 11(10). doi: 10.3390/biomedicines11102719. Fulltekst i vitenarkiv Vis sammendrag

  Specific signalling thresholds of the WNT/β-catenin pathway affect embryogenesis and tissue homeostasis in the adult, with mutations in this pathway frequently occurring in cancer. Excessive WNT/β-catenin activity inhibits murine anterior development associated with embryonic lethality and accounts for the driver event in 80% of human colorectal cancers. Uncontrolled WNT/β-catenin signalling arises primarily from impairment mutation in the tumour suppressor gene APC that otherwise prevents prolonged stabilisation of β-catenin. Surprisingly, no inhibitor compounds for WNT/β-catenin signalling have reached clinical use in part owing to the lack of specific in vivo assays that discriminate between on-target activities and dose-limiting toxicities. Here, we present a simple in vivo assay with a binary outcome whereby the administration of candidate compounds to pregnant and phenotypically normal Apcflox/flox mice can rescue in utero death of Apcmin/flox mutant conceptus without subsequent post-mortem assessment of WNT/β-catenin signalling. Indeed, the phenotypic plasticity of born Apcmin/flox conceptus enables future refinement of our assay to potentially enable dosage finding and cross-compound comparisons. Thus, we show for the first time the suitability of endogenous WNT/β-catenin signalling during embryonic development to provide an unambiguous and sensitive mammalian in vivo model to assess the efficacy and bioavailability of potential WNT/β-catenin antagonists.

• Uzhytchak, Mariia; Smolková, Barbora; Frtús, Adam; Stupakov, Alexandr; Lunova, Mariia & Scollo, Federica [Vis alle 11 forfattere av denne artikkelen] (2023). Sensitivity of endogenous autofluorescence in HeLa cells to the application of external magnetic fields. Scientific Reports. 13(1). doi: 10.1038/s41598-023-38015-x. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Dramatically increased levels of electromagnetic radiation in the environment have raised concerns over the potential health hazards of electromagnetic fields. Various biological effects of magnetic fields have been proposed. Despite decades of intensive research, the molecular mechanisms procuring cellular responses remain largely unknown. The current literature is conflicting with regards to evidence that magnetic fields affect functionality directly at the cellular level. Therefore, a search for potential direct cellular effects of magnetic fields represents a cornerstone that may propose an explanation for potential health hazards associated with magnetic fields. It has been proposed that autofluorescence of HeLa cells is magnetic field sensitive, relying on single-cell imaging kinetic measurements. Here, we investigate the magnetic field sensitivity of an endogenous autofluorescence in HeLa cells. Under the experimental conditions used, magnetic field sensitivity of an endogenous autofluorescence was not observed in HeLa cells. We present a number of arguments indicating why this is the case in the analysis of magnetic field effects based on the imaging of cellular autofluorescence decay. Our work indicates that new methods are required to elucidate the effects of magnetic fields at the cellular level.

• Kristiansen, Cecilie Katrin; Furriol, Jessica; Chen, Anbin; Sullivan, Gareth John; Bindoff, Laurence Albert & Liang, Xiao (2023). Deoxyribonucleoside treatment rescues EtBr-induced mtDNA depletion in iPSC-derived neural stem cells with POLG mutations. The FASEB Journal. ISSN 0892-6638. 37(9). doi: 10.1096/fj.202300650RR. Fulltekst i vitenarkiv Vis sammendrag

  Mutations in POLG, the gene encoding the catalytic subunit of the mitochondrial DNA (mtDNA) polymerase gamma (Pol-γ), lead to diseases driven by defective mtDNA maintenance. Despite being the most prevalent cause of mitochondrial disease, treatments for POLG-related disorders remain elusive. In this study, we used POLG patient-induced pluripotent stem cell (iPSC)-derived neural stem cells (iNSCs), one homozygous for the POLG mutation c.2243G>C and one compound heterozygous with c.2243G>C and c.1399G>A, and treated these iNSCs with ethidium bromide (EtBr) to study the rate of depletion and repopulation of mtDNA. In addition, we investigated the effect of deoxyribonucleoside (dNs) supplementation on mtDNA maintenance during EtBr treatment and post-treatment repopulation in the same cells. EtBr-induced mtDNA depletion occurred at a similar rate in both patient and control iNSCs, however, restoration of mtDNA levels was significantly delayed in iNSCs carrying the compound heterozygous POLG mutations. In contrast, iNSC with the homozygous POLG mutation recovered their mtDNA at a rate similar to controls. When we treated cells with dNs, we found that this reduced EtBr-induced mtDNA depletion and significantly increased repopulation rates in both patient iNSCs. These observations are consistent with the hypothesis that mutations in POLG impair mtDNA repopulation also within intact neural lineage cells and suggest that those with compound heterozygous mutation have a more severe defect of mtDNA synthesis. Our findings further highlight the potential for dNs to improve mtDNA replication in the presence of POLG mutations, suggesting that this may offer a new therapeutic modality for mitochondrial diseases caused by disturbed mtDNA homeostasis.

• LaLone, Vernon; Aizenshtadt, Aleksandra; Goertz, John; Skottvoll, Frøydis Sved; Mota, Marco Barbero & You, Junji [Vis alle 15 forfattere av denne artikkelen] (2023). Quantitative chemometric phenotyping of three-dimensional liver organoids by Raman spectral imaging. Cell Reports Methods. 3(4). doi: 10.1016/j.crmeth.2023.100440. Fulltekst i vitenarkiv Vis sammendrag

  Confocal Raman spectral imaging (RSI) enables high-content, label-free visualization of a wide range of molecules in biological specimens without sample preparation. However, reliable quantification of the deconvoluted spectra is needed. Here we develop an integrated bioanalytical methodology, qRamanomics, to qualify RSI as a tissue phantom calibrated tool for quantitative spatial chemotyping of major classes of biomolecules. Next, we apply qRamanomics to fixed 3D liver organoids generated from stem-cell-derived or primary hepatocytes to assess specimen variation and maturity. We then demonstrate the utility of qRamanomics for identifying biomolecular response signatures from a panel of liver-altering drugs, probing drug-induced compositional changes in 3D organoids followed by in situ monitoring of drug metabolism and accumulation. Quantitative chemometric phenotyping constitutes an important step in developing quantitative label-free interrogation of 3D biological specimens.

• Mathisen, Andreas Frøslev; Abadpour, Shadab; Legøy, Thomas Aga; Paulo, Joao A.; Ghila, Luiza Mihaela & Scholz, Hanne [Vis alle 7 forfattere av denne artikkelen] (2023). Global proteomics reveals insulin abundance as a marker of human islet homeostasis alterations. Acta Physiologica. ISSN 1748-1708. 239(2). doi: 10.1111/apha.14037. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Aim The variation in quality between the human islet samples represents a major problem for research, especially when used as control material. The assays assessing the quality of human islets used in research are non‐standardized and limited, with many important parameters not being consistently assessed. High‐throughput studies aimed at characterizing the diversity and segregation markers among apparently functionally healthy islet preps are thus a requirement. Here, we designed a pilot study to comprehensively identify the diversity of global proteome signatures and the deviation from normal homeostasis in randomly selected human‐isolated islet samples. Methods By using Tandem Mass Tag 16‐plex proteomics, we focused on the recurrently observed disparity in the detected insulin abundance between the samples, used it as a segregating parameter, and analyzed the correlated changes in the proteome signature and homeostasis by pathway analysis. Results In this pilot study, we showed that insulin protein abundance is a predictor of human islet homeostasis and quality. This parameter is independent of other quality predictors within their acceptable range, thus being able to further stratify islets samples of apparent good quality. Human islets with low amounts of insulin displayed changes in their metabolic and signaling profile, especially in regard to energy homeostasis and cell identity maintenance. We further showed that xenotransplantation into diabetic hosts is not expected to improve the pre‐transplantation signature, as it has a negative effect on energy balance, antioxidant activity, and islet cell identity. Conclusions Insulin protein abundance predicts significant changes in human islet homeostasis among random samples of apparently good quality.

• Olsen, Christine; Wang, Chencheng; Aizenshtadt, Aleksandra; Abadpour, Shadab; Lundanes, Elsa & Skottvoll, Frøydis Sved [Vis alle 11 forfattere av denne artikkelen] (2023). Simultaneous LC–MS determination of glucose regulatory peptides secreted by stem cell–derived islet organoids. Electrophoresis. ISSN 0173-0835. 44(21-22), s. 1682–1697. doi: 10.1002/elps.202300095. Fulltekst i vitenarkiv Vis sammendrag

  Abstract For studying stem cell–derived islet organoids (SC‐islets) in an organ‐on‐chip (OoC) platform, we have developed a reversed‐phase liquid chromatography–tandem mass spectrometry (RPLC–MS/MS) method allowing for simultaneous determination of insulin, somatostatin‐14, and glucagon, with improved matrix robustness compared to earlier methodology. Combining phenyl/hexyl‐C18 separations using 2.1 mm inner diameter LC columns and triple quadrupole mass spectrometry, identification and quantification were secured with negligible variance in retention time and quantifier/qualifier ratios, negligible levels of carryover (&lt;2%), and sufficient precision (±10% RSD) and accuracy (±15% relative error) with and without use of an internal standard. The obtained lower limits of quantification were 0.2 µg/L for human insulin, 0.1 µg/L for somatostatin‐14, and 0.05 µg/L for glucagon. The here‐developed RPLC–MS/MS method showed that the SC‐islets have an insulin response dependent on glucose concentration, and the SC‐islets produce and release somatostatin‐14 and glucagon. The RPLC–MS/MS method for these peptide hormones was compatible with an unfiltered offline sample collection from SC‐islets cultivated on a pumpless, recirculating OoC (rOoC) platform. The SC‐islets background secretion of insulin was not significantly different on the rOoC device compared to a standard cell culture well‐plate. Taken together, RPLC–MS/MS method is well suited for multi‐hormone measurements of SC‐islets on an OoC platform.

• Lemonche, Gerard Boix; Nagymihaly, Richard; Niemi, Essi Maria; Josifovska, Natasha; Johansen, Stian & Moe, Morten Carsten [Vis alle 8 forfattere av denne artikkelen] (2023). Intracorneal Implantation of 3D Bioprinted Scaffolds Containing Mesenchymal Stromal Cells Using Femtosecond-Laser-Assisted Intrastromal Keratoplasty. Macromolecular Bioscience. ISSN 1616-5187. 23. doi: 10.1002/mabi.202200422. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Injury of the cornea is a complex biological process. Regeneration of the corneal stroma can be facilitated by the presence of mesenchymal stromal cells (MSCs) and application of tissue equivalents. A new tissue‐engineering strategy for corneal stroma regeneration is presented using cellularized 3D bioprinted hydrogel constructs implanted into organ cultured porcine corneas using femtosecond laser‐assisted intrastromal keratoplasty. The ex vivo cultured, MSC‐loaded 3D bioprinted structures remain intact, support cell survival, and contain de novo synthesized extracellular matrix components and migrating cells throughout the observation period. At day 14 postimplantation, the cellularized tissue equivalents contain few or no cells, as demonstrated by optical coherence tomography imaging and immunofluorescent staining. This study successfully combines a laboratory‐based method with modern, patient‐care practice to produce a cell‐laden tissue equivalent for corneal implantation. Optimal bioink composition and cellularization of tissue equivalents are essential in fine‐tuning a method to promote the current technique as a future treatment modality.

• Andersen, Ina Marie; Reims, Henrik Mikael; Grzyb, Krzysztof; Fevang, Børre; Melum, Espen & Aukrust, Pål [Vis alle 10 forfattere av denne artikkelen] (2023). Long-term survival after liver transplantation in patients with common variable immunodeficiency. Liver transplantation. ISSN 1527-6465. 29(8), s. 894–899. doi: 10.1097/LVT.0000000000000130. Fulltekst i vitenarkiv
• Frerker, Nadine; Karlsen, Tommy Aleksander; Stensland, Maria; Nyman, Tuula Anneli; Rayner, Simon & Brinchmann, Jan Engelsen (2023). Comparison between articular chondrocytes and mesenchymal stromal cells for the production of articular cartilage implants. Frontiers in Bioengineering and Biotechnology. 11. doi: 10.3389/fbioe.2023.1116513. Fulltekst i vitenarkiv Vis sammendrag

  Focal lesions of articular cartilage give rise to pain and reduced joint function and may, if left untreated, lead to osteoarthritis. Implantation of in vitro generated, scaffold-free autologous cartilage discs may represent the best treatment option. Here we compare articular chondrocytes (ACs) and bone marrow-derived mesenchymal stromal cells (MSCs) for their ability to make scaffold-free cartilage discs. Articular chondrocytes produced more extracellular matrix per seeded cell than mesenchymal stromal cells. Quantitative proteomics analysis showed that articular chondrocyte discs contained more articular cartilage proteins, while mesenchymal stromal cell discs had more proteins associated with cartilage hypertrophy and bone formation. Sequencing analysis revealed more microRNAs associated with normal cartilage in articular chondrocyte discs, and large-scale target predictions, performed for the first time for in vitro chondrogenesis, suggested that differential expression of microRNAs in the two disc types were important mechanisms behind differential synthesis of proteins. We conclude that articular chondrocytes should be preferred over mesenchymal stromal cells for tissue engineering of articular cartilage.

• Kwak, Dongho; Combriat, Thomas Michel Daniel; Jensenius, Alexander Refsum & Olsen, Petter Angell (2023). Characterization of Mechanical and Cellular Effects of Rhythmic Vertical Vibrations on Adherent Cell Cultures. Bioengineering. 10(7), s. 1–19. doi: 10.3390/bioengineering10070811. Fulltekst i vitenarkiv Vis sammendrag

  This paper presents an innovative experimental setup that employs the principles of audio technology to subject adherent cells to rhythmic vertical vibrations. We employ a novel approach that combines three-axis acceleration measurements and particle tracking velocimetry to evaluate the setup’s performance. This allows us to estimate crucial parameters such as root mean square acceleration, fluid flow patterns, and shear stress generated within the cell culture wells when subjected to various vibration types. The experimental conditions consisted of four vibrational modes: No Vibration, Continuous Vibration, Regular Pulse, and Variable Pulse. To evaluate the effects on cells, we utilized fluorescence microscopy and a customized feature extraction algorithm to analyze the F-actin filament structures. Our findings indicate a consistent trend across all vibrated cell cultures, revealing a reduction in size and altered orientation (2D angle) of the filaments. Furthermore, we observed cell accumulations in the G1 cell cycle phase in cells treated with Continuous Vibration and Regular Pulse. Our results demonstrate a negative correlation between the magnitude of mechanical stimuli and the size of F-actin filaments, as well as a positive correlation with the accumulations of cells in the G1 phase of the cell cycle. By unraveling these analyses, this study paves the way for future investigations and provides a compelling framework for comprehending the intricate cellular responses to rhythmic mechanical stimulation.

• Busek, Mathias; Aizenshtadt, Aleksandra; Koch, Timo; Frank, Anna; Delon, Ludivine Sylvie Claude & Martinez, Mikel Amirola [Vis alle 12 forfattere av denne artikkelen] (2023). Pump-less, recirculating organ-on-a-chip (rOoC) platform. Lab on a Chip. ISSN 1473-0197. doi: 10.1039/D2LC00919F. Fulltekst i vitenarkiv
• Oskarsdotter, Kristin; Säljö, Karin; Sämfors, Sanna; Niemi, Essi Maria; Li, Susann & Simonsson, Stina [Vis alle 10 forfattere av denne artikkelen] (2023). Autologous endothelialisation by the stromal vascular fraction on laminin-bioconjugated nanocellulose-alginate scaffolds. Biomedical Materials. ISSN 1748-6041. 18(4). doi: 10.1088/1748-605X/acdebb. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Establishing a vascular network in biofabricated tissue grafts is essential for ensuring graft survival. Such networks are dependent on the ability of the scaffold material to facilitate endothelial cell adhesion; however, the clinical translation potential of tissue-engineered scaffolds is hindered by the lack of available autologous sources of vascular cells. Here, we present a novel approach to achieving autologous endothelialisation in nanocellulose-based scaffolds by using adipose tissue-derived vascular cells on nanocellulose-based scaffolds. We used sodium periodate-mediated bioconjugation to covalently bind laminin to the scaffold surface and isolated the stromal vascular fraction and endothelial progenitor cells (EPCs; CD31 + CD45 − ) from human lipoaspirate. Additionally, we assessed the adhesive capacity of scaffold bioconjugation in vitro using both adipose tissue-derived cell populations and human umbilical vein endothelial cells. The results showed that the bioconjugated scaffold exhibited remarkably higher cell viability and scaffold surface coverage by adhesion regardless of cell type, whereas control groups comprising cells on non-bioconjugated scaffolds exhibited minimal cell adhesion across all cell types. Furthermore, on culture day 3, EPCs seeded on laminin-bioconjugated scaffolds showed positive immunofluorescence staining for the endothelial markers CD31 and CD34, suggesting that the scaffolds promoted progenitor differentiation into mature endothelial cells. These findings present a possible strategy for generating autologous vasculature and thereby increase the clinical relevance of 3D-bioprinted nanocellulose-based constructs.

• Oldereid, Tine Simensen; Jiang, Xiaojun; Nordhus, Kathrine Sivertsen; Ponzetta, Andrea; Bjørnholt, Jørgen & Björkström, Niklas K. [Vis alle 8 forfattere av denne artikkelen] (2023). Role of bacteria and microbial metabolites in immune modulation during early life. Scandinavian Journal of Immunology. ISSN 0300-9475. doi: 10.1111/sji.13336. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Host–microbiome interplay from birth is essential for immune imprinting and tuning. Live gut microbes and microbial‐derived metabolites regulate the development and modulation of the immune system, but whether microbial metabolites solely are sufficient to induce immune maturation remains unclear. Sterile faecal filtrates (FFT) were generated from murine gut contents. Newborn germ‐free (GF) mice were treated twice daily with FFT (GF‐FFT) or saline (GF‐NaCl) from post‐natal day 5 until 4 weeks of age. A third group of GF neonates were conventionalized by the transfer of caecal microbiota with live gut microbes. Host immune compartments were comprehensively immunophenotyped and systemically analysed in all available immune‐related organs using flow cytometry. Oral FFT was associated with reduced survival among neonates (n = 7/19; 36.8% mortality), while saline treatment was well tolerated (n = 1/17, 5.9% mortality). Four‐week‐old FFT‐treated pups were comparable in body weight to GF‐NaCl, and the major B‐cell, conventional T‐cell and unconventional T‐cell subsets were unchanged from saline‐treated mice. Live bacteria administered during early life induced clear changes in proportions of B cells, T cells and T‐cell subsets in all mucosal tissues and secondary lymphoid organs compared to GF‐FFT, including restoration of intestinal natural killer T (NKT) cells with characteristics similar to conventional pups. Our findings show that oral administration of a FFT made of microbial metabolites, antigens and bacteriophages alone is insufficient to induce normal immune development elicited by the presence of live bacteria. Reduced survival during neonatal FFT treatment suggests a potential bioactive attribute of sterile faecal filtrates.

• Abadpour, Shadab; Niemi, Essi Maria; Orrhult, Linnea Strid; Hermanns, Carolin; Vries, Rick de & Nogueira, Liebert Parreiras [Vis alle 12 forfattere av denne artikkelen] (2023). Adipose-Derived Stromal Cells Preserve Pancreatic Islet Function in a Transplantable 3D Bioprinted Scaffold. Advanced Healthcare Materials. ISSN 2192-2640. 12(32). doi: 10.1002/adhm.202300640. Fulltekst i vitenarkiv Vis sammendrag

  Intra-portal islet transplantation is currently the only clinically approved beta cell replacement therapy, but its outcome is hindered by limited cell survival due to a multifactorial reaction against the allogeneic tissue in liver. Adipose-derived stromal cells (ASCs) can potentially improve the islet micro-environment by their immunomodulatory action. The challenge is to combine both islets and ASCs in a relatively easy and consistent long-term manner in a deliverable scaffold. W e report on manufacturing the Three-dimensional (3D) bioprinted double-layered scaffolds with primary islets and ASCs using a mix of alginate/nano-fibrillated cellulose (NFC) bioink. W e demonstrate the diffusion properties of the bioink and the supportive effect of human ASCs on islet viability, glucose sensing, insulin secretion and reducing the secretion of pro-inflammatory cytokines. Diabetic mice transplanted with islet-ASC scaffolds reached normoglycemia 7 days post transplantation with no significant difference between this group and the group received islets under the kidney capsules. In addition, animals transplanted with islet-ASC scaffolds stayed normoglycemic and showed elevated levels of C-peptide compared to mice transplanted with islet-only scaffolds. Our data presents a functional 3D bioprinted scaffold for islets and ASCs transplanted to the extrahepatic site and suggest a possible role of ASCs on improving the islet micro-environment.

• Kømurcu, Kristina Sæterdal; Wilhelmsen, Ingrid; Thorne, James L.; Krauss, Stefan Johannes Karl; Wilson, Steven Ray Haakon & Aizenshtadt, Aleksandra [Vis alle 7 forfattere av denne artikkelen] (2023). Mass spectrometry reveals that oxysterols are secreted from non-alcoholic fatty liver disease induced organoids. Journal of Steroid Biochemistry and Molecular Biology. ISSN 0960-0760. 232. doi: 10.1016/j.jsbmb.2023.106355. Fulltekst i vitenarkiv Vis sammendrag

  Oxysterols are potential biomarkers for liver metabolism that are altered under disease conditions such as non-alcoholic fatty liver disease (NAFLD). We here apply sterolomics to organoids used for disease modeling of NAFLD. Using liquid chromatography-mass spectrometry with on-line sample clean-up and enrichment, we establish that liver organoids produce and secrete oxysterols. We find elevated levels of 26-hydroxycholesterol, an LXR agonist and the first oxysterol in the acidic bile acid synthesis, in medium from steatotic liver organoids compared to untreated organoids. Other upregulated sterols in medium from steatotic liver organoids are dihydroxycholesterols, such as 7α,26–dihydroxycholesterol, and 7α,25-dihydroxycholesterol. Through 26-hydroxycholesterol exposure to human stem cell-derived hepatic stellate cells, we observe a trend of expressional downregulation of the pro-inflammatory cytokine CCL2, suggesting a protective role of 26-hydroxycholesterol during early-phased NAFLD disease development. Our findings support the possibility of oxysterols serving as NAFLD indicators, demonstrating the usefulness of combining organoids and mass spectrometry for disease modeling and biomarker studies.

• Hong, Yu; Kristiansen, Cecilie Katrin; Chen, Anbin; Nido, Gonzalo Sanchez; Høyland, Lena Elise & Ziegler, Mathias [Vis alle 9 forfattere av denne artikkelen] (2023). POLG genotype influences degree of mitochondrial dysfunction in iPSC derived neural progenitors, but not the parent iPSC or derived glia. Experimental Neurology. ISSN 0014-4886. 365. doi: 10.1016/j.expneurol.2023.114429. Fulltekst i vitenarkiv Vis sammendrag

  Diseases caused by POLG mutations are the most common form of mitochondrial diseases and associated with phenotypes of varying severity. Clinical studies have shown that patients with compound heterozygous POLG mutations have a lower survival rate than patients with homozygous mutations, but the molecular mechanisms behind this remain unexplored. Using an induced pluripotent stem cell (iPSC) model, we investigate differences between homozygous and compound heterozygous genotypes in different cell types, including patient-specific fibroblasts, iPSCs, and iPSC-derived neural stem cells (NSCs) and astrocytes. We found that compound heterozygous lines exhibited greater impairment of mitochondrial function in NSCs than homozygous NSCs, but not in fibroblasts, iPSCs, or astrocytes. Compared with homozygous NSCs, compound heterozygous NSCs exhibited more severe functional defects, including reduced ATP production, loss of mitochondrial DNA (mtDNA) copy number and complex I expression, disturbance of NAD+ metabolism, and higher ROS levels, which further led to cellular senescence and activation of mitophagy. RNA sequencing analysis revealed greater downregulation of mitochondrial and metabolic pathways, including the citric acid cycle and oxidative phosphorylation, in compound heterozygous NSCs. Our iPSC-based disease model can be widely used to understand the genotype-phenotype relationship of affected brain cells in mitochondrial diseases, and further drug discovery applications.

• Wilhelmsen, Ingrid; Martinez, Mikel Amirola; Stokowiec, Justyna; Wang, Chencheng; Aizenshtadt, Aleksandra & Krauss, Stefan Johannes Karl (2023). Characterization of human stem cell-derived hepatic stellate cells and liver sinusoidal endothelial cells during extended in vitro culture. Frontiers in Bioengineering and Biotechnology. 11. doi: 10.3389/fbioe.2023.1223737. Fulltekst i vitenarkiv Vis sammendrag

  Background: There is a significant need for predictive and stable in vitro human liver representations for disease modeling and drug testing. Hepatic stellate cells (HSCs) and liver sinusoidal endothelial cells (LSECs) are important non-parenchymal cell components of the liver and are hence of relevance in a variety of disease models, including hepatic fibrosis. Pluripotent stem cell- (PSC-) derived HSCs (scHSCs) and LSECs (scLSECs) offer an attractive alternative to primary human material; yet, the suitability of scHSCs and scLSECs for extended in vitro modeling has not been characterized. Methods: In this study, we describe the phenotypic and functional development of scHSCs and scLSECs during 14 days of 2D in vitro culture. Cell-specific phenotypes were evaluated by cell morphology, immunofluorescence, and gene- and protein expression. Functionality was assessed in scHSCs by their capacity for intracellular storage of vitamin A and response to pro-fibrotic stimuli induced by TGF-β. scLSECs were evaluated by nitric oxide- and factor VIII secretion as well as endocytic uptake of bioparticles and acetylated low-density lipoprotein. Notch pathway inhibition and co-culturing scHSCs and scLSECs were separately tested as options for enhancing long-term stability and maturation of the cells. Results and Conclusion: Both scHSCs and scLSECs exhibited a post-differentiation cell type-specific phenotype and functionality but deteriorated during extended culture with PSC line-dependent variability. Therefore, the choice of PSC line and experimental timeframe is crucial when designing in vitro platforms involving scHSCs and scLSECs. Notch inhibition modestly improved long-term monoculture in a cell line-dependent manner, while co-culturing scHSCs and scLSECs provides a strategy to enhance phenotypic and functional stability.

• Harrison, Sean Philip; Siller, Richard; Tanaka, Yoshiaki; Dugarte, Maria Eugenia Chollet; Morena-Barrio, María Eugenia de la & Xiang, Yangfei [Vis alle 36 forfattere av denne artikkelen] (2023). Scalable production of tissue-like vascularized liver organoids from human PSCs. Experimental and Molecular Medicine. ISSN 1226-3613. 55, s. 2005–2024. doi: 10.1038/s12276-023-01074-1. Fulltekst i vitenarkiv Vis sammendrag

  Abstract The lack of physiological parity between 2D cell culture and in vivo culture has led to the development of more organotypic models, such as organoids. Organoid models have been developed for a number of tissues, including the liver. Current organoid protocols are characterized by a reliance on extracellular matrices (ECMs), patterning in 2D culture, costly growth factors and a lack of cellular diversity, structure, and organization. Current hepatic organoid models are generally simplistic and composed of hepatocytes or cholangiocytes, rendering them less physiologically relevant compared to native tissue. We have developed an approach that does not require 2D patterning, is ECM independent, and employs small molecules to mimic embryonic liver development that produces large quantities of liver-like organoids. Using single-cell RNA sequencing and immunofluorescence, we demonstrate a liver-like cellular repertoire, a higher order cellular complexity, presenting with vascular luminal structures, and a population of resident macrophages: Kupffer cells. The organoids exhibit key liver functions, including drug metabolism, serum protein production, urea synthesis and coagulation factor production, with preserved post-translational modifications such as N-glycosylation and functionality. The organoids can be transplanted and maintained long term in mice producing human albumin. The organoids exhibit a complex cellular repertoire reflective of the organ and have de novo vascularization and liver-like function. These characteristics are a prerequisite for many applications from cellular therapy, tissue engineering, drug toxicity assessment, and disease modeling to basic developmental biology.

• Dalmao-Fernandez, Andrea; Aizenshtadt, Aleksandra; Bakke, Hege Gilbø; Krauss, Stefan Johannes Karl; Rustan, Arild Christian & Thoresen, G. Hege [Vis alle 7 forfattere av denne artikkelen] (2023). Development of three-dimensional primary human myospheres as culture model of skeletal muscle cells for metabolic studies. Frontiers in Bioengineering and Biotechnology. 11, s. 1–13. doi: 10.3389/fbioe.2023.1130693. Fulltekst i vitenarkiv Vis sammendrag

  Introduction: Skeletal muscle is a major contributor to whole-body energy homeostasis and the utilization of fatty acids and glucose. At present, 2D cell models have been the most used cellular models to study skeletal muscle energy metabolism. However, the transferability of the results to in vivo might be limited. This project aimed to develop and characterize a skeletal muscle 3D cell model (myospheres) as an easy and low-cost tool to study molecular mechanisms of energy metabolism. Methods and results: We demonstrated that human primary myoblasts form myospheres without external matrix support and carry structural and molecular characteristics of mature skeletal muscle after 10 days of differentiation. We found significant metabolic differences between the 2D myotubes model and myospheres. In particular, myospheres showed increased lipid oxidative metabolism than the 2D myotubes model, which oxidized relatively more glucose and accumulated more oleic acid. Discussion and conclusion: These analyses demonstrate model differences that can have an impact and should be taken into consideration for studying energy metabolism and metabolic disorders in skeletal muscle.

• Skogvold, Hanne Bendiksen; Wilson, Steven Ray Haakon; Rønning, Per Ola; Ferrante, Linda; Opdal, Siri Hauge & Rognum, Torleiv Ole [Vis alle 8 forfattere av denne artikkelen] (2023). A global metabolomics minefield: Confounding effects of preanalytical factors when studying rare disorders. Analytical Science Advances (ASA). 4(7-8), s. 255–266. doi: 10.1002/ansa.202300010. Fulltekst i vitenarkiv Vis sammendrag

  A common challenge when studying rare diseases or medical conditions is the limited number of patients, usually resulting in long inclusion periods as well as unequal sampling and storage conditions. The main purpose of this study was to demonstrate the challenges when comparing samples subject to different preanalytical conditions. We performed a global (commonly referred to as “untargeted”) liquid chromatography-high resolution mass spectrometry metabolomics analysis of blood samples from cases of sudden infant death syndrome and controls stored as dried blood spots on a chemical-free filter card for 15 years at room temperature compared with the same blood samples stored as whole blood at −80°C before preparing new dried blood spots using a chemically treated filter card. Principal component analysis plots distinctly separated the samples based on the type of filter card and storage, but not sudden infant death syndrome versus controls. Note that, 1263 out of 5161 and 642 out of 1587 metabolite features detected in positive and negative ionization mode, respectively, were found to have significant 2-fold changes in amounts corresponding to different preanalytical conditions. The study demonstrates that the dried blood spot metabolome is largely affected by preanalytical factors. This emphasizes the importance of thoroughly addressing preanalytical factors during study design and interpretation, enabling identification of real, biological differences between sample groups whilst preventing other factors or random variation to be falsely interpreted as positive results.

• Kogler, Stian; Kømurcu, Kristina Sæterdal; Olsen, Christine Sandsnes; Shoji, Jun-ya; Skottvoll, Frøydis Sved & Krauss, Stefan Johannes Karl [Vis alle 8 forfattere av denne artikkelen] (2023). Organoids, organ-on-a-chip, separation science and mass spectrometry: An update. TrAC. Trends in analytical chemistry. ISSN 0165-9936. 161. doi: 10.1016/j.trac.2023.116996. Fulltekst i vitenarkiv Vis sammendrag

  Organoids are 3D models of organs, grown in the laboratory from stem cells. An organ model grown/placed in microfluidic devices is commonly termed an “organ-on-a-chip”. Organoids and organ-on-a-chip devices are becoming important tools for studying physiology, disease modeling, drug discovery, personalized medicine, toxicology, and organ development/embryogenesis. We review how mass spectrometry is used for studying organoids and organ-on-a-chip-derived material. We first focus on proteomics, metabolomics/lipidomics, and hormones, typically discussing liquid chromatography-mass spectrometry (LC-MS) approaches. We then review work on mass spectrometry imaging (MSI) of organoids and discuss organ-on-a-chip coupled with mass spectrometry. The review focuses on research developments from the past four years. Mass spectrometric analysis of organoids and organ-on-a-chip has allowed novel insights on development and disease of e.g. brain, liver, and tumors, demonstrating potential for replacing or complementing animal models and other traditional model systems. Additional applications are emerging, e.g. related to sports doping and environmental toxicology.

• Jiang, Xiaojun; Otterdal, Kari; Chung, Brian K.; Maucourant, Christopher; Rønneberg, Jørgen Dybevik & Zimmer, Christine L [Vis alle 14 forfattere av denne artikkelen] (2023). Cholangiocytes Modulate CD100 Expression in the Liver and Facilitate Pathogenic T-Helper 17 Cell Differentiation. Gastroenterology. ISSN 0016-5085. doi: 10.1053/j.gastro.2023.11.283. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Låstad, Silja Borring; Abbasova, Nigar; Ho, Richard David Jun-Geet; Combriat, Thomas Michel Daniel & Dysthe, Dag Kristian (2025). Segmentation-free measurement of cell motion from quantitative phase imaging. Fulltekst i vitenarkiv
• Låstad, Silja Borring; Abbasova, Nigar; Combriat, Thomas Michel Daniel & Dysthe, Dag Kristian (2025). Cell height, area and volume fluctuations in MDCK monolayers. Fulltekst i vitenarkiv
• Carlsson, Per Ola; Hu, Xiaomeng; Scholz, Hanne; Ingvast, Sofie; Lundgren, Torbjörn & Scholz, Tim [Vis alle 12 forfattere av denne artikkelen] (2025). Survival of Transplanted Allogeneic Beta Cells with No Immunosuppression. doi: 10.1056/NEJMoa2503822. Fulltekst i vitenarkiv
• Busek, Mathias (2024). Scientia Podcast. [Internet]. https://www.med.uio.no/english/research/scientia-fellows/new. Fulltekst i vitenarkiv
• Busek, Mathias (2024). Pump-less recirculating Organ-on-Chip (rOoC) platform – a versatile platform for biomedical research. Fulltekst i vitenarkiv
• Busek, Mathias (2024). The pumpless recirculating Organon-Chip platform – a versatile platform for improved organoid loading. Fulltekst i vitenarkiv
• Busek, Mathias (2024). Organ-on-chip meets sensor technology - applications and use-cases for (bio) sensors in preclinical testing. Fulltekst i vitenarkiv
• Roman, Giacomo; Lauritzen, Knut Husø; Harrison, Sean Philip; Sullivan, Gareth John; Iversen, Nina & Henriksson, Carola Elisabeth [Vis alle 10 forfattere av denne artikkelen] (2023). OC 07.1 Autologous CRISPR/Cas9 Correction of a Missense Variant from a Patient with Severe, Inherited FVII Deficiency. Research and Practice in Thrombosis and Haemostasis (RPTH). 7(Oral communications ISTH 2023). doi: 10.1016/j.rpth.2023.100475. Fulltekst i vitenarkiv
• Scholz, Hanne & Ræder, Helge (2023). Response to Comment on Carrasco et al. Spatial Environment Affects HNF4A Mutation-Specific Proteome Signatures and Cellular Morphology in hiPSC-Derived β-Like Cells. Diabetes 2022;71:862-869. Diabetes. ISSN 0012-1797. 72(5). doi: 10.2337/dbi23-0007. Fulltekst i vitenarkiv
• Olsen, Christine & Eeltink, Sebastiaan (2023). Winner of the Analytical Science Advances Young Scientist Award 2022 at the 25th Norwegian symposium on chromatography: Christine Olsen. Analytical Science Advances (ASA). 4(7-8), s. 275–277. doi: 10.1002/ansa.202300040. Fulltekst i vitenarkiv
• Busek, Mathias (2023). Organ-on-a-chip interview by Inven2. [Internet]. https://www.inven2.com/organ-on-a-chip/. Fulltekst i vitenarkiv
• Busek, Mathias (2023). Cellspace: The revolving Organ-on-Chip (rOoC) platform. Fulltekst i vitenarkiv
• Busek, Mathias (2023). Pump-less Organ-on-a-Chip platform: A versatile tool for cell biological research. Fulltekst i vitenarkiv
• Busek, Mathias (2023). Pump-less Organ-on-chip platform for the functional co-culture of human circulating immune cells and 3D liver tissue representations. Fulltekst i vitenarkiv
• Busek, Mathias (2023). The Pumpless-recirulating Organ-on-Chip platform (rOoC). Fulltekst i vitenarkiv
• Kogler, Stian; Aizenshtadt, Aleksandra; Harrison, Sean Philip; Sullivan, Gareth John; Lundanes, Elsa & Bogen, Inger Lise [Vis alle 9 forfattere av denne artikkelen] (2023). Organ-in-a-column – automated on-line incubation, sampling, and LC-MS analysis for measurement of drug metabolites. Fulltekst i vitenarkiv
• Anderson, Colin C.; Bonney, Elizabeth A.; Mueller, Thomas F.; Corthay, Alexandre Benoit; Havele, Calliopi & Singh, Nevil J. [Vis alle 8 forfattere av denne artikkelen] (2023). On antigen-specific signals, immune class regulation and energetics: Report III from the workshops on foundational concepts of immune regulation. Scandinavian Journal of Immunology. ISSN 0300-9475. 98(3). doi: 10.1111/sji.13311. Fulltekst i vitenarkiv Vis sammendrag

  Abstract This is a report from a one‐week workshop held in Athens, Greece in July of 2022. The workshop aimed to identify emerging concepts relevant to the fundamentals of immune regulation and areas for future research. Theories of immune regulation emphasize the role of T cell help or co‐stimulation (signal 2). The workshop participants considered how new data on the characteristics of agonist antigens, the role of the antigen receptor signals (signal 1) in driving fate decisions, the effect of energetics on immunity and a better understanding of class‐control in the immune response, may impact theories of immune regulation. These ideas were discussed in the context of tumour immunology, autoimmunity, pregnancy and transplantation. Here we present the discussions as a narrative of different viewpoints to allow the reader to join the conversation. These discussions highlight the evolving understanding of the nature of specific antigen recognition and how both antigen‐specific and non‐specific mechanisms impact immune responses.

• Vogt, Yngve; Krauss, Stefan Johannes Karl; Mossige, Joachim; Dysthe, Dag Kristian; Angheluta, Luiza & Jensenius, Alexander Refsum (2023). Bereder grunnen for kunstige organer. [Journal]. Apollon. Fulltekst i vitenarkiv
• Røberg-Larsen, Hanne; Kømurcu, Kristina Sæterdal; Kogler, Stian; Olsen, Christine; Skottvoll, Frøydis Sved & Aizenshtadt, Aleksandra [Vis alle 8 forfattere av denne artikkelen] (2023). Organoids, Organ-on-a-chip and Mass Spectrometry. Fulltekst i vitenarkiv
• Midtøy, Lise; Kømurcu, Kristina Sæterdal; Kogler, Stian; wilhelmsen, ingrid; Røberg-Larsen, Hanne & Wilson, Steven Ray Haakon (2023). Sensitive targeted proteomic analysis of cholesterol metabolism enzymes in hepatic stellate cells - going towards single cell analysis. Fulltekst i vitenarkiv
• Haavaag, Jon Erlend; Kogler, Stian; Zawadzka, Malgorzata Elzbieta; Krauss, Stefan Johannes Karl; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2023). Building a high-resolution nano DESI-MS for organoid imaging: Analysis using a built and optimized imaging system. Fulltekst i vitenarkiv
• Schöb, Franziska Jessica; Dysthe, Dag Kristian; Scholz, Hanne; Binder, Alexander & Malthe-Sørenssen, Anders (2026). From Pixels to Phenotypes: Deep Learning on Label-Free Microscopy Data for Cell Fate Prediction How Algorithms Help Us See More. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  In this thesis, we used supervised deep learning on label-free microscopy data to predict cell fate and state from purely visual information, without relying on fluorescent labeling or manual segmentation. Across three studies, we combined phase-contrast and holotomographic imaging with convolutional neural networks to tackle problems that are central to stem cell biology and cancer research: predicting the differentiation efficiency of induced pluripotent stem cell clones, identifying germ-layer lineages in differentiating cultures, and detecting macrophage-induced cancer cell death. By building segmentation-free pipelines that operated directly on image patches, we reduced the need for explicit cell masks and made our methods easier to deploy in realistic, noisy experimental settings. The overarching results showed that biological label-free images contained sufficient morphological information for deep networks to recover biologically meaningful patterns, but also revealed clear limits to what static morphology could predict. In stem cell differentiation, our models already distinguished high- from lowefficiency clones early in the protocol, and learned image cues that matched intuitive notions of colony coverage and uniformity. In germlayer prediction, endpoint-trained models decoded lineage identity from holotomographic morphology and reconstructed a plausible timeline of lineage divergence when applied retrospectively, while struggling more in mixed cultures with overlapping lineages. In the cancer cell death study, deep learning distinguished dying from alive cells at the time of death, yet early prediction beyond a short pre-death window remained difficult, indicating that death morphology emerged abruptly rather than gradually over many hours. Together, these findings support the view that deep learning on label-free microscopy could provide non-destructive, scalable readouts of cell fate, while emphasizing the need for time-aware models, richer training labels, and improved domain generalization to fully exploit biological label-free imaging in biomedical workflows.

• Kwak, Dongho; Jensenius, Alexander Refsum; Danielsen, Anne; Scholz, Hanne & Olsen, Petter Angell (2023). Music for cells? Rhythmic mechanical stimulations of cell cultures. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  This dissertation investigates how acoustic parameters and musical elements can be generated and manipulated to induce beneficial mechanical stimulations and alterations in cell cultures. The research has been conducted as part of a life science convergence environment, and the theoretical framework and experimental method in this dissertation are derived from three different disciplines: biology, music technology, and physics. The theoretical discussions centre around biological cell sensing mechanisms, the physical limitations and potentiality of audible sound to be used as mechano-acoustic cellular stimuli, and the concept of rhythm from biology and music technology perspectives. The methods include audio signal processing, physical characterisation of the experimental setup, various biological assays, and microscopic image feature extraction. Such a radically interdisciplinary approach culminated in laboratory experiments involving sound vibrations of human cell cultures using a vertical vibration system controlled by synthesized audio signals. The experimental variables included: No Vibration (NV, control), Continuous Vibration (CV), Regular Pulse (RP), and Variable Pulse (VP). The CV condition was categorised as non-rhythmic in this dissertation, while RP and VP were categorised as rhythmic conditions. The results demonstrate alterations in F-actin filament structure (length, thickness, angle) and the tendency of increased levels of cells in the G1-phase cell cycle in vibrated cell cultures. The “effect” was more apparent under the non-rhythmic (CV) condition than rhythmic conditions (RP and VP). The results also show that F-actin filament structural properties are negatively correlated (r < -.9), and the number of cells in the G1-phase cycle is positively correlated (r > .9) in relation to the magnitudes of mechanical parameters (RMS acceleration and shear stress). Nevertheless, the biological mechanism(s) responsible for the observed effects has yet to be characterised. The results from this dissertation inspire further studies on the effects of rhythmic mechanoacoustic stimulation on cellular biological rhythms (e.g., regulation of CLOCK, PER, and CRY genes).

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