148 ANAPHYLAXIS 



actin formation evidently run a parallel course, and that there is 

 no good reason for doubting their identity. This, at least, seems 

 established for the anaphylactic reaction product which is formed 

 as the result of the parenteral introduction of albumins. In the case 

 of animal or vegetable cells, on the other hand, there is evidence 

 to show that the cytolytic amboceptors may play the role of the 

 anaphylactins. 



Complement and Production of Anaphylactic Toxin. That comple- 

 ment is necessary for the production of the anaphylactic toxin has 

 been demonstrated beyond a doubt. Friedemann and Friedberger 

 have thus shown that when fresh complement is added to a mixture 

 of an albumin and its corresponding antiserum, in the test-tube, a 

 toxic product (anaphylatoxin) is formed which, upon injection into 

 a suitable animal, calls forth practically all the characteristic 

 symptoms of anaphylaxis. Quite in accord with this observation 

 is the fact that during the anaphylactic reaction, produced in the 

 usual way, the complement of the blood is reduced to one-fifth 

 or even to one-half of the original amount, and that the shock 

 cannot be prevented by the artificial introduction from without of 

 complement, even in large amount. Moreover, if an animal (such 

 as the pigeon) which is biologically far removed from the rabbit, 

 and whose complement does not supplement the action of any 

 amboceptors formed in the latter, is injected with the serum from 

 a sensibilized animal of this order, and then reinjected with the 

 corresponding antigen, no anaphylactic shock should theoretically 

 develop and, as matter of fact, does not develop. As in the test-tube 

 experiment, furthermore, the action of complement can be prevented 

 through the addition of a suitable amount of salt, i. e., by raising the 

 osmotic pressure of the mixture; so, also, is it possible to prevent 

 the development of the anaphylactic shock in sensitized animals 

 by a preliminary injection of large amounts of salt. 



Nature of Anaphylactic Toxin. Regarding the nature of the 

 anaphylactic poison, our knowledge is as yet quite meagre. If we 

 regard the action of the amboceptor-complement combination upon 

 the albuminous antigen as comparable to the digestion of proteins 

 by the digestive ferments of the gastro-intestinal tract, in other 

 words as a parenteral digestion, then we can also suppose that the 

 anaphylactic poison represents some cleavage product of the protein 

 molecule. As a matter of fact, there is a certain similarity in the 



