Serological characterization of humoral lectin from Heterometrus granulomanus scorpion hemolymph.

A lectin in the hemolymph of Indian scorpion Heterometrus granulomanus was detected by agglutination of human and animal erythrocytes. The agglutinating activity was enhanced in presence of Ca2+ ion. The lectin shows specificity for sialic acid like many other sialic acid-specific lectins such as "Limulin", as the agglutination of erythrocytes was completely abolished by treatment with Vibrio cholerae neuraminidase. However, neuraminidase-treated rat and mouse erythrocytes exhibited high titers. This result was substantiated by crossed-absorption test which suggests the adjunct specificity of the Heterometrus lectin for these cells. Hemagglutination-inhibition results of the lectin indicate that sialic acid including its derivatives and sialoglycoconjugates are the inhibitors among which glycophorin was most potent.