A retina-derived stimulator(s) of retinal pigment epithelial cell and astrocyte proliferation.

Retinal detachments are frequently accompanied by retinal pigment epithelial cell and glial cell proliferation. This may be important in the pathogenesis of proliferative vitreoretinopathy and may also play a role in the failure of some eyes to regain visual function despite anatomically successful retinal reattachment surgery. In this study, we demonstrate that a retina-derived substance or substances stimulates the proliferation of retinal pigment epithelial cells (250% above control) and astrocytes (150% above control) in vitro. The stimulation of proliferation occurs in the absence of serum, but is accentuated by serum. There is some degree of target-cell specificity as there is no stimulation of smooth-muscle-cell proliferation. Morphologic changes induced in the proliferating cell types as well as preliminary characterization suggest that one or more of the previously described eye-derived growth factors may be involved.