Fibronectin in the Ocular Lens

FN is a common extra cellular matrix (ECM) protein and its splice variants are associated with a wound healing response. Using immunofluorescent staining we have shown that FN concentrations progressively increase as the back of the posterior capsule is approached and that it is localized to the center portion of the posterior capsule and the outermost front portion of the anterior capsule contain FN. RT‐PCR investigation revealed FN mRNA in both lens cell types (epithelial and fiber cells). Additional RT‐PCR analysis of the major splice variants of FN (EDA and EDB) showed that epithelial cells have a higher amount of EDB FN than fiber cells. Inversely, fiber cells displayed EDA FN while epithelial cells did not. When comparing this finding with our immunofluorescent finding that only EDA exists in the posterior capsule, it can be speculated that EDA FN is produced by the fiber cells. Conversely, the location of the anterior capsular FN suggests that it has extraneous origins. It is important to understand the distribution of the two variants in normal lenses in order to see how this distribution might change in wound healing responses such as post cataract surgery clouding.