QUANTITATIVE ANALYSIS OF N-LINKED GLYCOPROTEINS IN TEAR FLUID OF CLIMATIC DROPLET KERATOPATHY BY GLYCOPEPTIDE CAPTURE AND ITRAQ.

LEI ZHOU; R. W. BEUERMAN,; AI PING CHEW,; SIEW KWAN KOH; TA CAFARO ,; EA URRETS-ZAVALIA,; JA URRETS-ZAVALIA,; HM SERRA.

J. Proteom. Res.

ACS PUBLICATIONS

Año: 2009 vol. 8 p. 1992 - 1992

1535-3893

Glycoproteins are potentially important biomarkers of disease and therapeutictargets. In particular, the N-linked glycoproteins are a focus of interest as theycan be found in the extracellular environment and body fluids. In this study, wehave sampled the tears, the extra-cellular fluid of the epithelial cells covering thesurface of the eye, of patients with climatic droplet keratopathy, CDK, using tearsof unaffected normals for comparison. Pre-fractionation of the tear sample useda hydrazide-resin capture method, and the previously N-glycosylated peptideswere then subjected to two-dimensional nano-LC-nano-ESI-MS/MS analysis toobtain peptide fragmentation patterns for identification through protein databasesearches. We have identified a total of 43 unique N-glycoproteins, 19 of whichhave not previously been reported in tear fluid. In addition, we havequantitatively compared N-glycoprotein profiles in tear fluid of pa