THE PROTECTIVE ACTION OF TYPE I ANTIPNEUMOCOCCUS SERUM IN MICE

Abstract

The first paper deals with demonstrations of some of the variables encountered in mouse protection tests for the evaluation of antipneumococcic serum. By varying the quantitative relationships between antibody and culture injected certain characteristics were noted, such as the "Schwellenwert," the prozone, and the limiting titer zone. The effect upon the test of variable host factors and of modifications in technic are also described.[long dash]Paper II describes the infectious process in mice injected with type I pneumococci, and the effect of antipneumococcic serum upon the infection. The number and nature of cells present in the peritoneum at the time of injection of serum and culture are believed to have an important influence on the outcome of the test, and the monocyte is considered to be the first line of body defense against infection. Support is given to the belief that the protective action of antipneumococcic serum is dependent upon 3 specific actions: neutralization of capsular polysaccharide; agglutination of organisms; and sensitization of pneumococci; all of which favor phagocytosis.[long dash]Paper III describes the interrelationships of various factors involved in the protection test. The smaller mice and those with large numbers of white cells in the peritoneal cavity were better able to utilize the passively conferred immune bodies.