An improved semi-quantitative enzyme immunostaining procedure for glycosphingolipid antigens on high performance thin...

An immunoassay is described which allows the detection of glycosphingolipid (GSL) antigens on high performance thin layer chromatograms (HPTLC). The method involves: (1) the separation of GSL on HPTLCs; (2) incubation with specific antibodies against carbohydrate structures of GSL, and (3) the detection of specifically bound antibodies with alkaline phosphatase-conjugated second antibodies and 5-bromo-4-chloro-3-indolyl-phosphate (BCIP) as substrate. Using a monoclonal rat IgG2c antibody against Forssman GSL, a BALB/c monoclonal antibody against asialo GM2, and polyclonal rabbit antibodies against asialo GM1, it was shown that as little as 3 ng GSL antigen could be detected in a procedure taking detected in a procedure taking only 4 h to perform. The assay should be useful for screening mono- and polyclonal antibodies with potential specificity for GSL antigens, for the detection and quantification of GSL-antigens in tissue extracts, and for defining the specificity of anti-GSL antibodies.