The influence of extracellular matrix on lens epithelial cell viability
Posterior capsular opacification is the main complication of cataract surgery and results from the proliferation, migration and differentiation of lens epithelial cells remaining in the capsular bag. To better understand this pathological cell behaviour, 1 investigated the interactions between lens epithelial cells and the bovine lens capsule in vitro and their effect on cell viability. As determined by a colorimetric cell proliferation assay, in vitro culture of cells directly on the bovine lens capsule resulted in maintained cell viability in the presence of staurosporine in both lens epithelial cell lines tested, but in neither of the two non-lens cell lines tested. As determined by immunoblotting and reverse-transcriptase polymerase chain reaction (RT-PCR), cell viability on the bovine lens capsule could further be correlated to the presence of both ɑA-crystallin and αB-crystallin expression. A positive correlation of cell viability on the lens capsule with vimentin and HSP27 expression was also found in a smaller set of cell lines. As determined by gelatin zymography and immunoblotting, MMP-2 was expressed by lens epithelial cells, led to the release of FGF-2 and IGF-1 from the lens capsule and correlated with lens epithelial cell viability. Taken together, these results suggest that the lens capsule can act as a store of releasable growth factors available to the lens epithelial cells, with effects on their protein expression and cell viability.