260 



COLLECTED STUDIES IN IMMUNITY. 



TABLE VI. 

 Ox BLOOD + AMBOCEPTOR OF AN OX-BLOOD RABBIT + GUINEA- PIG SERUM. 



The study of the phenomena of immunization has taught us that 

 nothing is so liable to error as premature generalization. Hence 

 we were not at all surprised to find that there are cases in which, 

 in contrast to that above described, the quantity of anticomplement 

 required appeared exclusively to be a function of the amount of 

 complement, and in no way dependent on the degree of occupation 

 of the receptors by amboceptors. Curiously enough this case con- 

 cerns the combination first described, namely, sheep blood, ambo- 

 ceptor of goats treated with sheep blood, and guinea-pig serum as 

 complement, with this difference, however, that in this case the anti- 

 complement was not the same, since it was derived from a rabbit treated 

 with guinea-pig serum. This anticomplement, therefore, so far as its 

 relation to guinea-pig serum was concerned, can be termed "iso- 

 genic" in contrast to the anticomplement previously used, which 

 can be termed "alloiogenic," since it was derived by injecting rabbit 

 serum. The experiment is shown in Table VII. 



Here we see that neutralization of the ten times larger amount of 

 complement, such as is made necessary by the smaller amount of 

 amboceptor, requires ten times as much anticomplement as it does 

 with one-tenth the quantity of complement when larger amounts 

 of amboceptor are used. 



