[Immunohistochemical findings in proliferative retinal diseases--on the significance of fibronectin, macrophages and transferrin].

Surgically excised vitreoretinal membranes of different etiology were analyzed immunochemically using the APAAP stain. We investigated the presence of macrophages, lymphocytes, proliferating cell antigen, fibronectin, vimentin, cytokeratin, transferrin (TF), and the TF receptor. Fibronectin and vimentin were observed both in idiopathic and traumatic proliferative vitreoretinopathy (PVR); however, abundant macrophages were a typical feature only of traumatic PVR. A Coats' disease specimen contained fibronectin, vimentin, TF, and macrophages. Staining for proliferating cell antigen, lymphocytes, and cytokeratin was negative in all specimens. TF was detected in all membranes, and it was possible to label the receptor in 11 of 14 patients. TF quantities in native human vitreous were measured to be 65.7 mg/l by ELISA. TF is an essential growth factor for cultured cells, and current evidence suggests that TF may be involved in the pathogenesis of proliferative intraocular disease.