Ron Jans Award: Proteomic lacrimal gland analysis of various pathologies of the ocular surface

Ron Jans Award Recipient

Authors: Jean-Yves Sahyoun, Marie-Claude Robert. Université de Montréal- CHUM.

Author Disclosure Block: J. Sahyoun: None. M. Robert: None.

Title: Proteomic lacrimal gland analysis of various pathologies of the ocular surface

Abstract Body:

Purpose: Mucous membrane pemphigoid (MMP) and lichen planus (LP) are orphan diseases leading to chronic conjunctivitis with scar formation and corneal blindness. Diagnosis is confirmed by biopsy, but this is positive in only 30% to 80% of cases and can lead to local aggravation of the disease. In order to overcome these difficulties as well as to further explore the pathophysiology of these diseases, we are developing a non-invasive technique for proteomic analysis of tears.
Study Design: This is a prospective cohort study. Participants will be recruited during their medical visits to the CHUM ( centre hospitalier de l'université de Montréal), either in a context of isolated follow-up in ophthalmology or during their follow-up at the multidisciplinary clinic of bullous diseases of the CHUM.
Methods: Proteins are collected with the Schirmer test, then digested with trypsin. The peptides from enzymatic digestion are then analyzed by liquid chromatography together with tandem mass spectrometry (LC-MS/MS) with non-targeted protein analysis, in “data-independent” mode. The relative content of identified peptides in tears were compared between MMP, LP and control eyes.
Results: A total of 102 samples were analyzed from 14 patients with MMP (Foster Stage 1 to 4), 3 patients with LP and 20 control patients. In total, 481 proteins were identified and quantified and among these, the quantities of myeloperoxidase (MPO), matrix metallopeptidase-9 (MMP-9) and neutrophil collagenase (MMP-8) were found to be significantly higher in MMP (ratio of 4.90, 3.06 and 2.11 respectively) and LP (ratio of 6.06, 6.55 and 4.83 respectively) than in the controls (p<0.05).
Conclusions: MPO, MMP-9 and MMP-8 are inflammatory biomarkers of cicatrizing conjunctivitis. Our proteomic approach could improve diagnostic sensitivity and allow treatment to be better targeted based on disease activity.