Public defence Agnese Compagnone 30/01/2025 - Implementation of in vivo models to identify potential candidates for DED treatment - Department Pharmaceutical Sciences
Public defence Agnese Compagnone 30/01/2025 - Implementation of in vivo models to identify potential candidates for DED treatment - Department Pharmaceutical Sciences
Promotors: Prof. Paul Cos - Prof. Peter Delputte
Location: Q002
Abstract:
This thesis explores the development of an evaporative dry eye (EDE) animal model based on Meibomian gland cauterisation, aiming to replicate the tear film alteration caused by Meibomian gland dysfunction (MGD), a major driver of EDE. Dry eye disease (DED), which causes ocular surface inflammation, pain, and discomfort, is a multifactorial condition with significant impact on quality of life. EDE is the most common subtype, linked to MGD, which impairs lipid secretion from Meibomian glands, increasing the tear evaporation rate. The cauterisation method, as suggested by existing literature, faced challenges: technique variability and unclear guidelines on how many glands to cauterise or whether both eyelids should be involved. These inconsistencies can compromise the model’s reliability, indicating the need for further optimisation to ensure reproducibility and consistency in experimental outcomes.
This thesis also presents a novel multiplex electrochemiluminescence immunoassay (ECLIA) for detecting key biomarkers in rat tear samples, critical for DED research. Biomarkers such as interleukin-17 (IL-17), matrix metalloproteinase-9 (MMP-9), and intercellular adhesion molecule-1 (ICAM-1) were targeted. The assay was validated with promising results, showing that the detection ranges for these biomarkers met the required parameters, though precision was identified as a limiting factor. Variations were mainly due to human error, such as pipetting inconsistencies and evaporation during incubation. Suggestions for improving precision include standardising operator expertise, minimising reagent variability, and controlling incubation conditions. These improvements would increase reliability and broaden the assay's detection range.
Additionally, the thesis investigates the role of oxidative stress and ferroptosis in DED. Ferroptosis, a form of iron-dependent cell death linked to lipid peroxidation, is thought to contribute to DED pathogenesis. In vitro studies with the ferroptosis inhibitor UAMC-3203 suggested potential in reducing oxidative stress. However, clear evidence for ferroptosis in DED models was not found. In vivo tests showed that UAMC-3203 could restore GPX4 gene expression closer to the control group, hinting at potential benefits of ferroptosis inhibition.
Finally, the thesis proposes optimising the EDE model with inflammation-triggering agents like LFA-1 and ICAM-1 inhibitors, or toll-like receptor agonists, to enhance chronicity and inflammation. The use of advanced 3D cell culture models for better simulation of the ocular surface is also discussed, highlighting their potential for testing new therapies. Further research is needed to address the multifactorial causes of DED and improve treatments for this widespread condition