Mouse Antibodies to Group a Streptococcal Carbohydrate; Use of Idiotypy to Detect Inbred Strain Specificity and to Monitor Spleen Cell Transfer in Syngenetic Mice

Abstract

Abstract The antibody response to the group A carbohydrate antigen was measured in SWR/J and A/J mice after intravenous (i.v.) immunization with whole heat-killed streptococcal vaccines. Microzone electrophoresis revealed antibodies with limited heterogeneity in both mouse strains. The light chains exhibited a restricted banding pattern by polyacrylamide disc electrophoresis. With the immunization procedure employed here, most SWR/J mice produced less than 1 mg of antibody per ml. The occasional mouse, however, produced 2 to 4 mg of antibody with restricted heterogeneity; such mice were used as donors for spleen cell transfers (107 spleen cells per recipient) to irradiated (500 R) recipient SWR/J mice. Antisera of recipient mice had antibody components identical to that of the donor as detected by microzone electrophoresis. Isolated antibody from one such SWR/J spleen cell recipient was used to prepare anti-idiotypic sera in rabbits. Idiotypy was detected by a hemagglutination inhibition assay. Antibody with the same idiotype was detected in the original donor mouse of the cell transfer experiments and in the majority of the mice of the first and second passage. This idiotypic specificity was not apparent in the antisera of SWR/J mice which received immune cells from a different donor. By use of the hemagglutination inhibition test, at least 5 out of 14 immunized SWR/J mice had a minor antibody component with the same idiotypy as that of the proband. This idiotype was not detected in the group A antibodies of 16 A/J mice immunized with the same antigen. This SWR/J idiotypic marker may be useful for genetic studies, because an antibody component with this idiotype occurred in the hybrid SWR/J × A/J.