Multi-omics Evaluation of an Immune-mediated Preclinical Model Reveals Novel Targets for Meibomian Gland Dysfunction

Abstract

Purpose : Dry Eye Disease (DED) is a complex disorder of the tear film, impacting vision and causing discomfort. The tear film consists of three layers: the lipid, aqueous, and mucin. The majority of DED is classified as evaporative dry eye, due to dysfunction and/or atrophy of the meibomian glands (MG), termed Meibomian Gland Dysfunction (MGD). MGD pathogenesis remains unclear, therefore, to better understand MGD and identify potential new targets we implemented a multi-omics approach leveraging the Allergic Eye Disease (AED) mouse model, which exhibits characteristics of MGD.

Methods : AED was induced in C57BL6 female mice following immunization then topical challenge with ovalbumin (OVA) and tearing, eyelid swelling, conjunctival chemosis, and MG plugging were monitored. Eyelids from naïve and AED were dissected to evaluate inflammation and gland changes using spatial transcriptomics (GeoMx, NanoString). Meibum was expressed from eyelids to assess if AED caused meibum lipid composition changes through liquid chromatography high-resolution mass spectrometry.

Results : Our findings reveal that the AED model displays many MGD characteristics, such as MG plugging, structural changes, and inflammation markers. Gene set enrichment analysis (GSEA) of spatially resolved transcriptome changes showed a significant increase of inflammatory changes in the inter-acini space (e.g., T cell differentiation (q-value≈0.09), response to IL-17 (q-value≈0.08), leukocyte aggregation (q-value≈0.01), and neutrophil migration (q-value≈4*10^-4)) with AED. There was also a significant decrease in the expression of extracellular matrix (ECM) assembly, and SMAD protein signal transduction limited to the duct (q-value≈0.08 and 4*10^-3, respectively) and acini (q-value≈0.06 and 1*10^-3, respectively) compartments. However, while changes in meibum lipid content are associated to MGD, we did not find significant alterations after five days of ocular OVA challenge, suggesting that longer-term MG environment changes might be necessary to affect meibum lipid composition.

Conclusions : While the AED model does not fully replicate all aspects of MGD, it serves as a useful tool for studying immune-mediated changes related to MGD. Our results support further research to explore extracellular matrix (ECM) and SMAD as potential targets for MGD.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.