Myelin basic protein has lectin-like properties

Abstract

Myelin basic proteins (MBP) obtained from bovine, guinea pig and human nervous tissues exhibited hemagglutinating activity for erythrocytes of several animal species. The activity to each erythrocyte was actually equal among the 3 MBPs. With bovine MBP and chicken erythrocytes, the hemagglutinating activity did not require divalent cations and it was resistant to denaturing conditions such as urea treatment or heating of the protein. The activity was specifically inhibited by antisera to MBP, allowing hemagglutination inhibition assay to be a useful method for estimating antibody titers for MBP. Various sugars and glycoproteins were tested for their ability to inhibit MBP-mediated hemagglutination. Among mono- and disaccharides, only D-galactose and D-galactosamine exhibited an inhibitory effect at high concentration. Beta-Galactopyranoside was found to be 8-fold effective compared to alpha-anomer. Among glycoproteins, glycophorin and kappa-casein were potent inhibitors, while fetuin, ovalbumin and ovomucoid were ineffective. Either of the former two glycoproteins was observed to form a clear precipitin band with MBP in Ouchterlony double diffusion. Possible interaction of MBP with certain saccharide receptor was briefly discussed.