Studies on the production of normal bactericidal antibodies

Abstract

In trying to elucidate how normal bactericidal antibodies in serum can be produced, the authors performed some experiments on the bactericidal activity of chicken serum against Sal. typhosa 0-901 W and Sh. dysenteriae 1, and obtained the following results.1. The bactericidal action to these organisms appeared in 48 hours of post-hatching before feeding and its bactericidal power was as high as adult chicken. Injection of the heat-killed vaccine of the test organisms into chorioallantoic vein of 12 days old eggs had no effect on the appearance of the bactericidal action. It was, moreover, demonstrated that the producibility of immune antibody to the test organisms. commenced to appear at 5-7 eays of age.2. The bursa of Fabricius, consisting of lymphoid tissue and implicating to antibody production was extirpated a 1 week of age. No change of the bactericidal power of the bursectomized chicken was observed as compared with the intact control group. On the other hand, the immune response of antibody production to the challenged organisms was remarkably depressed.3. In order to prevent the development of bursa of Fabricius, 0.5-1 mg of testosterone was injected into albumen of 5 days old eggs. These hormon-treated chicken were unable to produce antibodies to the challenged organisms, whereas their serum possessed the strong bactericidal power to the test organisms.The origin of production of normal bactericidal antibodies can not be readily determined. Our findings. however, may lead to the conclusion that normal bactericidal antibodies are not produced as immune antibodies to antigens in microbes and food. but as normal globuline patterns with immunologically reactive group. The authors, accordingly, postulate the mode of the bactericidal action of normal serum as follow s. The eractive groups of normal bactericidal antibody combine “by accident” with the compatible determinants of test organism at the initial stage, and thereafter exhibit the bactericidal or bacteriolytic action in cooperation with complement and Mg ions.