Increased Cathepsin S activity associated with decreased protease inhibitory capacity contributes to altered tear proteins in Sjogren's Syndrome patients.

ABSTRACT: Cathepsin S (CTSS) activity is elevated in Sjögren's Syndrome (SS) patient tears. Here we tested whether protease inhibition and cystatin C (Cys C) levels are reduced in SS tears, which could lead to enhanced CTSS-driven degradation of tear proteins. CTSS activity against Cys C, LF and sIgA was tested in SS or healthy control tears. Tears from 156 female subjects (33, SS; 33, rheumatoid arthritis; 31, other autoimmune diseases; 35, non-autoimmune dry eye (DE); 24, healthy controls) were analyzed for CTSS activity and Cys C, LF, and sIgA levels. Cys C and LF showed enhanced degradation in SS tears supplemented with recombinant CTSS, but not supplemented healthy control tears. CTSS activity was significantly increased, while Cys C, LF and sIgA levels were significantly decreased, in SS tears

SUBMITTER: Edman MC 

PROVIDER: S-EPMC6056496 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature