Comparison of tear proteins between healthy and early diabetic retinopathy patients

To identify potential prognostic or diagnostic marker tear proteins for early diabetic retinopathy (DR) and to investigate the pathogenesis of this disease using proteomics techniques.

The tear proteins expressed in patients suffering from diabetes mellitus without the retinopathy symptoms, nonproliferative diabetic retinopathy and healthy volunteers were analyzed by 2-DE. The differentially expressed proteins in patients were identified by ESI-Q-TOF and confirmed by Western blotting.

Proteins which were differentially expressed with statistical significance (P<0.05) in two diabetic groups as compared to those in healthy group were selected and identified by ESI-Q-TOF MS/MS. Among these proteins, three proteins (LCN-1, HSP27 and B2M) were found to exhibit a progressive reduction in two disease groups. The expression levels of which might be useful as diagnostic biomarkers of DR were verified by Western blotting

Proteomic analysis using tear is a novel approach that can provide insight into possible biomarker and the pathogenesis of early DR.