Specificity of monoclonal antibodies against ABH and related structures tested by ELISA with synthetic glycoconjugates.

We have tested 88 monoclonal antibodies with proposed specificities against ABH- and related antigens in an ELISA with synthetic oligosaccharide conjugates as coating substances. All mabs were tested for binding towards A-, B-, and H type I trisaccharides, the B disaccharide, and the proposed anti-A and -AB were also tested on A tetrasaccharide type I. Of the 50 mabs with proposed A- and/or B-specificity, 28 showed a specific reaction in our ELISA. Cross-reactivity with other ABH-antigens was observed for 7 of these 50 anti-A/B mabs and 15 of them did not react in the ELISA. Only 2 of the 17 mabs submitted as anti-H bound to H trisaccharide type I, one of them showed a polyspecific reactivity pattern, and the remaining 14 did not react with our type I antigen. Of the mabs with other than ABH-specificities only one, supposedly anti-P1, showed cross-reactivity with one of our coating antigens, in this case the B trisaccharide.