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Trial Lecture – time and place
See Trial Lecture.
Adjudication committee
- First opponent: Associate Professor Jinyang Li, Wenzhou Medical University, China
- Second opponent: Assistant Professor Marlies Gijs, Maastricht University, The Netherlands
- Third member and chair of the evaluation committee: Professor Knut Tomas Dalen, University of Oslo
Chair of the Defence
Professor Emeritus Trond Buanes, University of Oslo
Principal Supervisor
Xiangjun Chen, Oslo University Hospital
Summary
Dry Eye Disease (DED) is the most prevalent condition in the field of ophthalmology. The disease is characterized by symptoms such as itching, soreness, and, in severe cases, impaired vision.
It is known that the female sex is a risk factor for the development of dry eyes, but there are still unanswered questions related to sex's role in the individual subtypes of DED.
The two most well-known underlying diseases of DED are Sjögren syndrome (SS) and meibomian gland dysfunction (MGD). The factor of sex, with genes and hormones, play various roles in the two.
The goal of this thesis is therefore twofold. Firstly, the genetic basis underlying sex differences in SS is aimed to be investigated, and secondly, sex differences in clinical measures of DED are aimed to be identified.
To investigate the influence of sex in SS, lacrimal glands from male and female mouse models for SS were collected. To investigate sex and age in patients with DED, visitors at the dry eye clinic were examined using a symptom score and a set of standardized clinical signs.
Thousands of genes were different between the sexes in the lacrimal gland of mouse models for SS. In the female mice (MRL strain), the upregulated genes were related to inflammatory responses. However, this gene profile was dependent on the mouse model, which indicates that the lacrimal gland microenvironment mediates the sex effect on gene expression.
As for the clinical studies on DED, females presented with worse signs across most parameters, although the sex differences were age-dependent. Sex and age differences were most consistent in tear film break-up time and meibomian expressibility, possibly related to meibomian gland functionality.
Finally, the review on MGD prevalence revealed that there is no substantial evidence for a sex difference in the prevalence of MGD. The poorer meibomian gland functionality among women in clinical settings may be attributed selection bias, considering differences in care seeking behavior.
Additional information
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