PREPARATION AND SPECIFICITIES OF ANTISERA TO BETA-1-]4 LINKED N-ACETYL-D-GLUCOSAMINE OLIGOSACCHARIDES

Antisera with specificities for (GlcNAc)n‡ oligosaccharides containing β1 → 4 glycosidic linkages were obtained by immunizations with the oligosaccharides coupled by the reductive amination reaction to bovine serum albumin and cytochrome-c as carrier proteins. The specificities of the antisera to the (GlcNAc)4- conjugates were analyzed by radioimmunoassay using 125I-labelled conjugates as antigens. Complete inhibition of the antibody-antigen reactions were obtained using either (GlcNAc)n oligosaccharides or unlabelled (GlcNAc)n conjugates where the (GlcNAc)n were coupled to either the same or different carriers as the one used for immunization. Inhibition of the antibody-125I-(GlcNAc)4-conjugate complex formation was obtained with ten fold less concentration of (GlcNAc)3 relative to (GlcNAc)4 and (GlcNAc)5 haptens because the (GlcNAc)n-conjugates have n-1 intact pyranose rings in the conjugate form. (GlcNAc)4-conjugates were the best inhibitors compared to conjugates with either smaller or larger oligosaccharide chains. No inhibition of the complex formation in the radioimmunoassays was observed using various glycoproteins, or glycoproteins partially degraded by periodate oxidation and the Smith degradation. © 1979.