Monoclonal antibody RG1 against rat Müller cells recognizes optic nerve and cerebral cortex glia in culture.

A monoclonal antibody designated as RG1 was produced by the fusion of mouse myeloma cells with spleen cells from mice immunized with rat retinas. The monoclonal antibody was shown to bind to Müller cells of the rat retina by the avidin-biotin peroxidase complex method. The screening of antibody-producing hybridomas and the analysis of the monoclonal antibody obtained were performed by enzyme-linked immunosorbent assay. The optic nerve, cerebral cortex and dorsal root ganglia were cultured from 17-day embryonic rats and maintained for 17-20 days. Expressions of the RG1 antigen were examined by indirect immunofluorescence in the cultured glial cells. In both the optic nerve and the cerebral cortex glial cells the RG1 antigen was expressed; however, the RG1 antigen was not expressed in cultured Schwann cells throughout the whole culture period. Our results suggest that the RG1 antigen is a common antigen in the supporting neuroectodermal glial cells in the central nervous system.