Retinitis pigmentosa: immunohistochemical and biochemical studies of the retina.

Several immunohistochemical and biochemical characteristics of retinas from two patients with retinitis pigmentosa (RP) were examined. Histochemically, interphotoreceptor retinoid-binding protein (IRBP) was found in the interphotoreceptor space in small areas of preserved peripheral retina, although enzyme-linked immunosorbent assay suggested that little IRBP was present. Antibodies to glial fibrillary acidic protein and factor VIII-related antigen corroborated retinal gliosis and retinal vessel attenuation, respectively, in the RP cases. Fibronectin showed similar staining in normal and affected tissue.