Antibodies against retinal pigmented epithelial cells induced RPE cell damage, loss of adhesion, and interphotoreceptor matrix proteins

Purpose: The primary causes of serous retinal detachment (SRD) remain elusive. One of etiology may involve autoimmune phenomena. We have developed an animal model for SRD. Methods: Animals were immunized with a retinal pigmented epithelial cell (RPE)-specific 65 kDa protein emulsified with complete Freund's adjuvant (CFA). Immunohistochemical, histological, electro-retino-graphic studies and ELISA assay and serum transfer experiment were done in these animals. Results: Rats injected with RPE cell-specific 65 kDa protein emulsified with CFA raised antibodies and developed FPE damage. Serum transfer studies clearly established that the RPE damage vas induced by humoral immunity. The RPE damage resulted in the loss of adhesion proteins and interphotoreceptor matrix (IPM) components including glycoaminoglycan (GAG), integrin, ICAM-1 and VCAM-1. Both RPE cell damage and loss of adhesion and IPM molecules, invariably preceded the detachment of neuro-retina from RPE cells. Conclusions: This experimental animal study of autoimmune RPE damage and SRD offers a model for human SRD. Furthermore, our studies suggest that primary cause of SRD in human is RPE damage induced by humoral autoimmunity.