Immunologic alteration of bacterium typhosum and of bacillus pestiscaviae by growth in sterile fixation abscesses

Abstract

Recently Blankenhorn, Ecker and King1 described a serum resistant typhoid bacillus from a tibial abscess. This organism was not only poorly agglutinable by heterologous antiserums, but also by homologous antiserum. It readily stimulated the formation of agglutinins, and was capable of specific absorption. We have kept it for a period of 17 months on plain agar, and found that it has maintained its original characteristics. Mcintosh and McQueen2 isolated a similar organism from the blood stream, and in this case the homologous antiserum also failed to agglutinate but did agglutinate ordinary Bacterium typhosum. Their nonagglutinable strain absorbed the agglutinin from homologous antiserum. A similar strain is reported by Toyoda,3 also isolated from the blood stream of the patient. Gay and Claypole4 showed that a typhoid bacillus from the blood of suspected carrier rabbits failed to be agglutinated by strong antiserum, and that passage of a readily agglutinable culture through a rabbit reduced its agglutinability. They further found that even subcultures of typhoid bacilli on rabbit-blood agar or on bile broth led to inagglutinability. The blood and bile cultures, however, are as readily agglutinable as agar strains by the serums of rabbits immunized against blood cultures. In this respect, then, the change of Gay's organism is less profound than that of the organisms described before. The occurrence of serum resistant forms is by no means uncommon, and little is known about conditions under which these variations take place or, as just pointed out by Larson and Greenfield,6 about the nature of the mechanism of the alteration. In view of these facts, it was thought of interest to try to produce these changes by growing, an organism to which the mouse is resistant and an organism to which it is not resistant in sterile fixation abscesses.