ANAPHYLACTIN (ALLERGIN) 555 



the role of precipitins themselves appear to have been excluded as directly 

 participating in the production of anaphylactic shock, recent experi- 

 ments of Zinsser 1 and others would tend to show that a precipitin 

 possesses the nature of a protein sensitizer or antibody that sensitizes 

 its antigen, just as a hemolytic amboceptor sensitizes its corpuscles, 

 precipitation being a secondary phenomenon due to the colloidal nature 

 of the reacting bodies under conditions of quantitative proportions and 

 environment that favor precipitation. This would assign to the pre- 

 cipitins and agglutinins an active though secondary role in the processes 

 of anaphylaxis and immunity. 



At the present time, therefore, we may tentatively assume that the 

 anaphylactin or allergin is of the nature of a specific lytic amboceptor 

 or albuminolysin, which, in conjunction with non-specific complement, 

 constitutes what is called a " ferment," and is capable of splitting a 

 protein molecule with the liberation or formation of a toxic moiety re- 

 sponsible for the lesions and symptoms of anaphylaxis. Just as other 

 normal amboceptors, such as hemolysins, are present in normal serum, 

 so these protein amboceptors or albuminolysins may be present for 

 various proteins, explaining the production of the anaphylaxis poison 

 in vitro with a normal serum when the latter is fresh and active, i. e., 

 when complement is present. 



Theoretically, at least, it should be possible to detect the anaphy- 

 lactic amboceptor in a serum by a method of complement fixation, 

 although practically this is not the case. The whole subject of "fer- 

 ments" requires further study, and, as a result, our knowledge and views 

 of antibodies and the processes of immunity in general are likely to 

 undergo some change. 



The Cellular Theory of Anaphylaxis. An interesting question in 

 this connection is whether the anaphylactic reaction is humoral or occurs 

 in the blood-stream, i. e., between the free anaphylactin or antibody 

 and the antigen, or whether it is cellular and occurs between the attached 

 or sessile antibodies and the antigen. Friedberger and Girgolaff 2 now 

 support the cellular theory, basing their belief on the results of their 

 experiments, which consisted of thoroughly washing the organs of a 

 sensitized animal with salt solution, and then transplanting them to a 

 normal animal, when the latter became sensitized. The recent and 

 brilliant studies of Dale, 3 whose investigations were carried out by the 



1 Jour. Exp. Medicine, 1913, 18, 219. 



2 Zeitschr. f. Immunitatsf., 1911, 9, 575. 



3 Jour, of Pharm. and Exper. Therap., 1913, 4, 167. 



