The brain-specific S-100 protein on neuronal cell membranes

The S-100 protein has been localized to the neuronal plasma membranes of isolated Deiters' neurons by fluorescence microscopy using fluorescein-conjugated antiserum to the protein and by immunoelectron microscopy using peroxidase-conjugated anti-S-100 antiserum. In the present study this is shown also by incubating neurons with Sepharose 4B or methylacrylate spherules to which were coupled anti-S-100 antibodies. The specificity of the antiserum is discussed in the text. The technique described can be used to study the topography of antigenic characteristics of nerve cells by using antisera insolubilized on spherules of suitable size.