n6 



Scientific Proceedings (49). 



These experiments in anti-anaphylaxis were originally per- 

 formed with horse serum. In order to avoid any possible source 

 of error, however, due to the complex character of this material 

 they were repeated with a solution of crystalline egg albumen 

 which had been four times re-crystallized, and the same results 

 were obtained. 



It appears from these experiments that anti-anaphylaxis is a 

 condition in which an animal becomes refractory to the toxic 

 effects of a foreign proteid simply through the exhaustion from his 

 blood of those bodies which induce the reaction. The proof 

 hereof lies in the fact that the simple re-introduction of these bodies 

 with the blood of another sensitized animal restores him at once 

 to his original condition of anaphylaxis. The bodies which induce 

 the reaction are, so far as we know, two: first, the "anaphylactic 

 anti-bodies," which resemble in character, and may be identical 

 with, the amboceptors; second, the complement substances of 

 the blood. 



It is unlikely that the complement is the substance herein at 

 fault, inasmuch as Friedemann states, as the complement is 

 rapidly restored to its normal amount in anti-anaphylactic pigs, 

 whereas the condition of anti-anaphylaxis persists. We have 

 tested whether the complement plays an important role by two 

 sets of experiments. In the first place, the animals have been 

 simultaneously sensitized by hypodermic injection to two different 

 forms of foreign proteid, namely horse serum and egg albumen. 

 They have then been rendered anti-anaphylactic to one of these. 

 Immediately, thereafter, it has been found that their sensitiveness 

 to the other albumen is little, if at all, impaired. This indicates 

 that the complement cannot be deficient. In the second type of 

 experiments, the pigs, having been made anti-anaphylactic to egg 

 albumen, have been given an intra-venous injection of 5 c.c. of 

 normal guinea-pig serum, which would, of course, suffice to supply 

 any defect of complement. When now re-injected with egg albu- 

 men, they fail to evidence any sensitiveness. This indicates, 

 therefore, that something other than complement, necessary to 

 the anaphylactic reaction, has been removed from the blood in 

 anti-anaphylaxis. It seems to us, therefore, that animals are 

 anti-anaphylactic simply through the absence of the appropriate 



