Comparative Expression of Extracellular Matrix Proteins in Human Cataracts and Lens Epithelial Cell Lines

Abstract

Abstract: : Purpose: Extracellular matrix (ECM) proteins play a significant role in adhesion and migration of lens epithelial cells leading to capsular opacification. To evaluate the expression of the ECM proteins, collagen type IV, fibronectin, vitronectin, and laminin by anterior lens epithelial cells (A-LEC) obtained from cataract patients, an immortalized human lens epithelial cell line (SRA1/4) and a primary rabbit lens epithelial cell line (N/N1003A). Methods: Circular sections of anterior capsules with attached A-LEC were obtained during cataract surgery from 50 patients. Each capsule was divided into four quadrants. Each quadrant of the lens capsule was immunohistochemically stained for collagen type IV, fibronectin, vitronectin and laminin. The cell lines underwent immunohistochemical staining and reverse transcriptase-polymerase chain reaction (RT-PCR) for all four ECM proteins. Results: Collagen type IV (96%) vitronectin (64%), fibronectin (14%) and laminin (14%) were detected in the A-LEC on the anterior capsules. Collagen type IV, fibronectin and laminin were also detected in N/N1003/A cells by reverse RT-PCR, but only weak expression of laminin was detected in the SRA 1/4 cells. Conclusions: We have observed marked differences in ECM protein expression by the immortalized SRA 1/4 cells in comparison to A-LEC from human cataracts and primary culture N/N1003A cells. This difference may be important when investigating capsular opacification.

Keywords: extracellular matrix • posterior capsular opacification (PCO) • immunohistochemistry