ANTIBODY RESPONSES TO BACTERIA - EFFECT OF IMMUNOGLOBULIN TYPE OF ANTI-BACTERIAL ANTIBODY ON IMMUNOCONGLUTININ STIMULATION IN RABBITS AND GUINEA-PIGS

  • 1 January 1967
    • journal article
    • research article
    • Vol. 13  (3) , 261-+
Abstract
Three manifestations of the antibody response of rabbits and guinea-pigs to injections of killed bacteria have been examined, namely, complement-fixing and agglutinating anti-bacterial antibodies and immunoconglutinins (I-Ks) directed against fixed complement. Animals given intramuscular injections of the bacteria in Freund''s complete adjuvant before a course of intravenous injections were compared with those receiving the latter course only. The prior immunization with organisms in adjuvant increased the I-K responses in rabbits. This was correlated with an increase in that part of the complement-fixing, anti-bacterial antibody contained in the IgG [immunoglobulin G] fraction. The animals receiving the course of intravenous injections only, produced more agglutinating anti-bacterial antibody (which was shown to be predominantly IgM in type) and less I-K. In guinea-pigs there was little difference in the I-K response between animals receiving the 2 injection schedules. The prior immunization with organisms in adjuvant did produce higher levels of anti-bacterial antibody, but in this species the increase was mainly in the IgM fraction. In both species the presence of complement-fixing antibacterial antibody of IgG immunoglobulin type is necessary for the stimulation of I-K production and that high levels of IgM antibody may have an inhibitory effect. High titers of I-K can be produced regularly by injecting bacteria intravenously into rabbits with predominantly IgG anti-bacterial antibodies. Where these do not occur naturally they can be produced in reponse to 2 intramuscular injections of bacteria in adjuvant. In guinea-pigs it was difficult to produce predominantly IgG anti-bacterial antibody and high titers of I-K were difficult to achieve.