A GENERAL REVIEW OF THE RECENT WORK IN IMMUNITY. 585 



are formed which, by uniting with the corresponding albuminous 

 bodies, possess the property of exerting anticomplementary effects. 

 In this case, therefore, the anticomplement action is brought about 

 by the interaction of two components, one present hi the serum of 

 the immunized animal and the other in the serum of that animal 

 species whose serum was used for immunization (Moreschi). It is 

 clear, of course, that here the dissolved albuminous substances, not 

 the complements, were the antigens. This being the case, the demon- 

 stration of anticomplements produced by immunization becomes 

 extremely difficult, and it must be left for future investigations to 

 see whether it is at all possible to differentiate these substances from 

 those antibodies against albuminous substances which exert an anti- 

 complement action. So far as the mechanism of the described anti- 

 complement action is concerned, I do not think that the observations 

 of Moreschi and Gay, that absorption of complement is associated with 

 precipitation, necessarily mean that precipitation and anticomplement 

 have any causal relationship. In fact it seems reasonable to assume, 

 in accordance with Gengou's first explanations, that the property of 

 binding the complements is exercised by the albuminous bodies sen- 

 sitized with the specific amboceptor. We would have to conceive 

 this somewhat in this fashion, that just as when immunizing with 

 cells, agglutinins and amboceptors are formed, so also when immuniz- 

 ing with dissolved albuminous bodies two kinds of antibodies are 

 formed, precipitins and amboceptors. If the latter, however, are 

 really amboceptors in the sense of Ehrlich and Morgenroth, we must 

 demand that they will have the same properties which we have always 

 ascribed to the amboceptor type. As a matter of fact, the experiment 

 shows that this is the case. These albumin amboceptors also, in order 

 to react with the complements, must have the affinity of their com- 

 plementophile apparatus raised, only in the present case this is effected 

 by the combination of the amboceptor with the susceptible body, the 

 albumin. We see, therefore, that this anticomplementary action cor- 

 responds to the deflection of complement through an excess of im- 

 mune body, first described by M. Neisser and Wechsberg. Only in 

 this case the deflecting amboceptor is of a different kind, and needs 

 first to react with the corresponding receptor. 



Through the researches of Wassermann and Schiitze and of Uhlen- 

 huth, one class of antibodies against dissolved albumins, namely, the 

 precipitins, has been used, as is well known to differentiate albuminous 

 bodies of various origin. These have thus come to be successfully 



