PRODUCTION OF THE ANAPHYLACTIC SHOCK 155 



bilisin of the French; the allergin of v. Pirquet) can be transferred 

 from one animal to another, in a manner quite analogous to the 

 production of passive immunity, and writers hence speak of passive 

 anaphylaxis, which may be homologous or heterologous, i. e., it 

 can be transferred to an animal of the same species or to one of a 

 species which is different from the one which was actively sensitized. 

 The discovery of this fact has had important bearings upon our 

 understanding of the mechanism which underlies the production 

 of the anaphylactic shock, for it showed conclusively that humoral 

 factors are here at play. 



Production of the Anaphylactic Shock. Richet originally propounded 

 the hypothesis that as a result of the first injection a special anti- 

 body is formed, which he termed toxogenin, and that this then splits 

 off a highly toxic poison from the primary toxin; for example, 

 from the anaphylactogenic principle of his actinocongestin. 

 This hypothesis, however, cannot be applied to the anaphylactic 

 reaction which follows the administration of non-toxic antigens, 

 and is evidently based upon false premises. Other writers, such 

 as Weichardt, v. Pirquet and Schick, Wolff-Eisner, Friedberger, 

 Friedemann and Isaac, also assume the formation of antibodies, 

 but suppose that a special toxin is set free from the corresponding 

 non-toxic antigen when the two meet. Regarding the manner in 

 which this occurs, different possibilities, of course, suggest them- 

 selves. Led by his observations on the anaphylactic reaction which 

 follows the introduction of alien cells into the rabbit, Wolff-Eisner 

 assumed a lytic action on the part of the anaphylactic antibody 

 upon the corresponding albuminous antigen, analogous to the lytic 

 action of the cytotoxins (e. g., bacteriolysins) and a consequent 

 liberation of endotoxin-like substances. Weichardt arrived at 

 similar conclusions on the basis of analogous experiments with 

 placental cells, but, unlike Wolff-Eisner, he assumed that the lytic 

 action of the antibody does not set free preformed endotoxins, but 

 that the lysis is followed by further chemical changes. 



More recent investigations, notably by Dorr and Russ, have 

 rendered it highly probable that the antibody in question is really 

 a precipitin, and the predominating idea at present is that an ana- 

 phylactic toxin is in some manner split off from the corresponding 

 precipitate through the agency of complement. This view is, as a 

 matter of fact, supported by numerous observations. It has thus 



