Demonstration of mononuclear phagocytes in a human epiretinal membrane using a monoclonal anti-human macrophage antibody

Proliferative vitreoretinopathy (PVR), the major complication of rhegmatogenous retinal detachment and posterior segment ocular trauma, is a multistage disease process eventually resulting in traction retinal detachment. The migration of macrophages to a site of disrupted barriers between the vitreous, retina, and choroidea, respectively, is considered to be an important step in the early pathogenesis of PVR. In this study, we demonstrate the presence of numerous mononuclear phagocytes in a human PVR membrane by an APAAP (alkaline phosphatase-anti-alkaline phosphatase) immunostain using a monoclonal mouse anti-human macrophage antibody. This finding correlates with a highly positive fibronectin immunostain in the same specimen. Our results warrant further investigation of the involvement of mononuclear phagocytes in vitreoretinal proliferative disorders.