Comparative radiochromatographic carbohydrate analysis of rabbit anti-hapten IgG antibodies of various affinities

Abstract

Hexosamine, mannose and galactose content of rabbit normal IgG and rabbit purified anti-hapten antibody IgG populations were determined by the radiochromatographic carbohydrate analysis. Carbohydrate analyses were performed on antibodies obtained at three time points after primary immunization and two time points after secondary immunization with DNP† conjugated proteins. Average sugar values per mole of anti-DNP antibody populations were: hexosamine, 13·2 moles; galactose; 3·1 moles; and mannose, 6·1 moles. For comparison, average values for the monosaccharide content per mole of normal rabbit IgG were: hexosamine, 13·0 moles; galactose, 2·3 moles; and mannose, 6·4 moles. Characterization of rabbit anti-DNP antibody populations by average intrinsic association constant ( K 0) and heterogeneity index ( a) showed that the antibodies analyzed were typical (i.e. binding constants and heterogeneity increased throughout the response). Concomitant with the large degree of antigen binding variability, variations were measured in the monosaccharide content of the IgG antibody molecules.