Some Aspects of the Antibody Response of Rabbits to Immunization With Enterobacterial Somatic Antigens

Summary The immunoglobulins of rabbits injected with bacterial cells or isolated somatic antigen of Salmonella enteritidis and Escherichia coli were separated by Sephadex G-200 gel filtration and the distribution of high and low molecular weight antibodies measured by bactericidal and other techniques. High molecular weight bactericidal antibody was the predominant form produced regardless of amount, form, or schedule in which somatic antigen was administered. However, evidence was obtained that significant amounts of 7S antibody could also be produced. Addendum. The report by Pike and Schulze on production of 7S and 19S antibodies to the somatic antigen of S. typhosa in rabbits (Proc. Soc. Exp. Biol. Med., 1964, v115, 829) appeared after our manuscript had been submitted for publication. Although dealing with the same general issue these papers differ considerably; viz., the present work employed additional enterobacterial specificities, compared bacteria and isolated somatic antigens, utilized a different procedure for serum fractionation and depended on different methods for measurement of antibody activities.