[Vitronectin and fibronectin receptors in proliferative retinal diseases]

Integrins are membrane receptors which, together with their corresponding adhesion proteins, constitute a versatile recognition system and provide cells with information for position, anchorage, differentiation, migration, and growth. Vitronectin and fibronectin are two potent mediators of cell adhesion which, together with their receptors, represent a highly sophisticated system of communication in proliferative intraocular disorders. Using an immunofluorescence technique, we demonstrate a similar pattern of partial colocalization of vitronectin and fibronectin in proliferative diabetic retinopathy (PDR) and proliferative vitreoretinopathy (PVR). Furthermore, we show the expression of the corresponding cell surface receptors for vitronectin and fibronectin in membranes from patients with traumatic PVR (n = 8), idiopathic PVR (n = 8), and PDR (n = 6). At this time, it seems that further studies on integrins and their significance in proliferative retinal disorders are necessary before pharmacological approaches based on receptor antagonism can prove themselves to be possible and clinically applicable.