Analysis of the effects of preservative-free tafluprost on the tear proteome

The purpose of the present study was to assess the ocular surface health status in primary open angle glaucoma (POAG) patients switching from topical application of preserved latanoprost (LT) to preservative-free tafluprost (PFT) by tear proteomic monitoring. Tear fluid of POAG patients showing dry eye symptoms, using LT and switching to PFT as well as tear fluid of healthy controls has been examined. Tear proteome dynamics was monitored over 24 weeks in a first mass spectrometric explorative analysis in a small POAG patient cohort (N = 3). Longitudinal responses of candidate proteins as well as cytokines were comparatively analyzed by microarray in a larger cohort of POAG patients (N = 16) and healthy controls (N = 15). Clinical parameters including tear breakup time (TBUT) and basal Schirmer test (BST) were recorded. Distinct post-switch level alterations could be documented in POAG tear proteins (> 1000). Cellular leakage proteins, dry eye related candidates and cytokines showed predominantly level diminishment in POAG patients and approximation to the tear protein level of healthy controls in response to PFT. Tear proteins like pyruvate kinase isozymes M1/M2 or galectin 7 displayed linear tear film level decline in POAG patients (R2≥0.9; P < 0.05) distinctly converging the healthy level. Proteomic outcome fit well with improved clinical parameters, TBUT and BST. In conclusion, tear proteomic alterations indicated ocular surface recovery regarding epithelia leakage and inflammation recession. Together with improved clinical parameters the study output proposes beneficial effects of PFT glaucoma therapy.