• The invasion of Bruch's membrane and subsequently the subpigment epithelium and subretinal spaces by proliferating choroidal capillaries is a prominent feature of age-related macular degeneration. The ability to isolate and propagate pure cultures of bovine choroidal microvascular endothelium, choroidal pericytes, turbinate fibroblasts, and bovine retinal pigment epithelium allowed us to identify a growth-promoting activity produced by the retinal pigment epithelium that stimulated the proliferation of these cells in vitro. This mitogenic activity is present in both retinal pigment epithelium-conditioned medium and retinal pigment epithelium extract and enhances the mitogenic activity of retinal-derived extract. The activity is resistant to extremes of temperature and pH but partially sensitive to trypsin inactivation.
Morse LS, Terrell J, Sidikaro Y. Bovine Retinal Pigment Epithelium Promotes Proliferation of Choroidal Endothelium In Vitro. Arch Ophthalmol. 1989;107(11):1659–1663. doi:10.1001/archopht.1989.01070020737038