Cultured human and rat oligodendrocytes and rat Schwann cells do not have immune response gene associated antigen (Ia) on their surface.

In order to determine if oligodendrocytes or Schwann cells had surface immune response gene associated antigen (Ia), we studied the binding of: (a) mouse monoclonal antibodies to rat Ia, to cultures of rat oligodendrocytes and Schwann cells; and, (b) mouse monoclonal antibodies to human Ia, to cultures of human oligodendrocytes employing radioimmunoassay and indirect immunofluorescence. Cells were identified using phenotypic markers; rabbit anti-galactocerebroside (GalC) for oligodendrocytes; rabbit anti-GalC and rabbit anti-Schwann cell for Schwann cells; rabbit anti-glial fibrillary acidic protein for astrocytes; rabbit anti-fibronectin for fibro-blasts and leptomeningeal cells, and the capacity to ingest latex particles for macrophage-microglia. Ia could not be detected on the surface of oligodendrocytes, Schwann cells, astrocytes, fibroblasts, or leptomeningeal cells. A small number of latex ingesting cells bound anti-Ia even after blocking of surface Fc receptors.