Receptors for immunoglobulin G demonstrated on human peripheral nerve fibres by electron microscopy.

The localization of class III of receptors for the Fc (fragment-crystallizable) region of immunoglobulin G (IgG) (Fc gamma RIII) on human peripheral nerve fibres was investigated by indirect immunoperoxidase staining of frozen nerve sections with the monoclonal antibody anti-Leu-IIb. Transmission electron microscopy revealed that Fc gamma RIII are localized to the entire surface membrane of the Schwann cell. Myelin and axons were not stained. Fc gamma RIII on human Schwann cells may be of significance in binding immune complexes, in phagocytosis, in release of lymphokines as well as cytotoxic and inflammatory mediators and in local immunoregulation.