Specific radioimmunoassay to investigate rod outer segment phagocytosis by retinal pigment epithelium in vitro.

A sensitive radioimmunoassay has been developed which allows rapid quantitation of rod outer segment (ROS) phagocytosis by retinal pigment epithelial (RPE) explants in vitro. It involves the use of an antiopsin antiserum, in conjunction with 125I-protein A as a second antibody, and utilizes permeabilization with ethanol to distinguish between the binding and ingestion phases of phagocytosis. This procedure will be used in the future to investigate potential regulatory factors of ROS phagocytosis by retinal pigment epithelium and to evaluate animal models of retinal degeneration.