ANAPHYLOTOXIN AND AMINO ACIDS. 



BY WILLIAM MC K. GERMAN. 



Shortly after the phenomenon of anaphylaxis was observed it was 

 noticed that both normal and sensitised sermn, ordinarily liarmless to the 

 same and other species upon injection, became highly toxic when sub- 

 jected to proper treatment, and produced symptoms identical with those 

 of anaphylaxis. The name anaphylotoxin has consequently arisen and 

 the phenomenon is thought by most workers to be closely related to that 

 which occurs iii vivo in a sensitised animal. 



Thus Friedmann has obtained a toxic principle by treating sensitised 

 cells with normal serum, which killed guinea pigs with typical symptoms. 

 Friedberger substantiated Friedmann's work by obtaining a similar poison 

 from sensitised bacteria and normal serum. To this he gave the name 

 anaphylotoxin. He believed of course that the poison arose not from the 

 serum but from the antigen — in this case from the bacteria. This is 

 logical and perfectly easy to believe. 



Later it was discovered that normal serum treated with such substances 

 as kaolin, talc and agar produced a similar poison. In that case could 

 that poison arise from the antigen ? Or could it arise from the serum ? 

 Friedberger believed that in the case of agar the poison came from the 

 small amount of nitrogen contained in the agar. Agar and other similar 

 colloids are normally harmless but when .'jcc of normal serum are treated 

 with 1 cc of a 0.5% solution of agar which has been shaken to form a 

 viscuous mass and exposed to 38 degrees for two liours it gives rise to 

 a })otent anaphylotoxin. Bordet and Zunz by freeing agar of all but a 

 trace of its nitrogen obtained a product which they called pararabine 

 and was identical with agar in all its physical characteristics. This, too, 

 gave rise to tlie same anaphylotoxin quantitatively while the nitrogenous 

 extracted residue proved to be quite harmless. Therefore Zunz would 

 have us conclude that the poison has for its source the serum of the animal 

 body and not the agar or the antigen in general. 



Bordet and Zunz further showed that with the production of anaphylo- 

 toxin there was an increase in amino acids, indicating cleavage. Their 

 method was briefly as follows: The serum was incubated at 38 degrees 

 with one-fifth its volume of 0.5% pararabine, centrifuged and the proteins 

 removed by precipitation with ten volumes 95% alcohol. The preciyiitate 



liitli Mlcli. Acad. Sci. Rept., i!ir;. 



