Antisera against ganglioside GM2: immunochemical and immunohistological studies

Antisera against ganglioside GM2 were raised in rabbits and tested by immunodiffusion, complement fixation and immunohistology. The presence of precipitating antibodies was demonstrated by immunodiffusion techniques (Ouchterlony and reversed Mancini). GM2-antibody titres were determined by a quantitative microcomplement fixation assay. The GM2-antibodies were shown to be specifically directed against GM2 and did not cross-react with the major brain gangliosides. Application of GM2-antiserum to brain sections from a case of GM2-gangliosidosis (Sandhoff's disease) in an immunofluorescence study produced a specific fluorescence of the granular GM2-storage material within the cytoplasm of cortical neurons. With immunoperoxidase staining by electron microscopy, labelling of the surface of the membraneous cytoplasmic bodies was obtained.