Characteristics of Streptococcal Group-Specific Antibody Isolated From Hyperimmune Rabbits

Abstract

A previous report described the development of the immune response in rabbits to streptococcal group-specific carbohydrates following intravenous immunization with streptococcal vaccines (1). I n a continuation of these studies, certain rabbits were noted to develop an unusually high level of streptococcal group-specific antibodies. Examination of the zone electrophoresis patterns of these immune sera revealed a remarkably sharp and narrow band within the ,y-globulin region. This report is concerned with the immunologic, chemical, and physical properties of the specific 3,o-globulin isolated from these sera. The findings suggest a selective manufacture in certain rabbits of specific immune 3,G-globulin which exhibits a restricted range of electrophoretic properties compared to that of the normal complement of q-globulin. Materials and MethodsStreptococd.--Group A-variant strain A486 was obtained from Dr. R. C. Lancefield of the Rockefeller University.RabMts.--7-1b. New Zealand red rabbits were supplied by Baumgartd Bunny Farm, Marion, Iowa.Streptococcal Vaccine.--The vaccine was prepared from Group A-variant streptococci, strain A486. The bacteria were grown in 1000 ml of DiSco Todd-Hewitt broth, collected by centrifugation, and washed three times with saline. The collected bacteria were resuspended in 10 ml of saline, adjusted to pH 2.0, which contained 1 mg/ml of pepsin, and were incubated for 2 hr at 37°C. The treated bacteria were washed two times with saline and finally resuspended in 50 ml of formalized saline. The vaccine was stored at 4°C.

The Emergence of Antibodies With Either Identical or Unrelated Individual Antigenic Specificity During Repeated Immunizations With Streptococcal Vaccines

“…In all of these studies, evidence for uniformity has been obtained by a combination of methods, including determination of allotypic markers, and N-terminal amino acid sequence of the light Chains (1)(2)(3)(4)(5)(6)12). The picture which emerges from these studies is that antibodies which have a readily demonstrable individual antigenic specificity are homozygous at both the a and b locus, even though they are derived from a doubly heterozygous rabbit (3).…”

“…For example, these antibodies and their light chains exhibit marked restriction in electrophoretic mobility (1,2). Quantitative precipitin studies with anti-allotypic sera indicate exclusion of allotypic markers (3).…”

“…The earlier studies on the uniform properties of streptococcal antibodies have been concerned primarily with antibodies to the carbohydrates of Groups A-variant and C streptococci (1,2,6,12). Similar uniformity is reported here for antibodies to Group A streptococci.…”

“…Electrophoretic Methods.--Zone eleetrophoresis was carried out on cellulose acetate membranes as previously described (1,2).…”

Purification of anti Streptococcus group a antibodies by affinity chromatography and isoelectric focusing

“…The occurrence of restricted antibody responses following immunisation with pneumococcal and streptococcal vaccines has in recent years greatly facilitated the isolation of homogeneous antibodies (10,11). KRAUSE has pointed out (7) that an antibody can be regarded as homogeneous when it lacks the manifestations of antibody heterogeneity, such as isotypic variations, allotypic variations, charge heterogeneity and functional heterogeneity.…”