MECHANISM OF THE ACTION OF ANTIAMBOCEPTORS. 565 



must call particular attention to the fact that the chief point in 

 Bordet's study, the non-specificity of the antiamboceptors so far as 

 the cytophile group is concerned, had already been published by 

 Pfeiffer and Friedberger. These authors have explained the fact 

 entirely in accordance with our views, as follows: 



"We are inclined to believe that the various immune bodies of 

 one and the same animal species possess one group in common which 

 in a way stamps them as coming from that particular animal organism. 

 The antiserum must possess certain relations to this group." To 

 this we would add that for the present it seems simplest to class this 

 group or groups, specific for the animal species, with the complemento- 

 phile group. In the amboceptor we differentiate a specific cytophile 

 group and a large apparatus made up of complementophile groups. 

 Aside from the property of anchoring the cells, the latter groups 

 exercise all the remaining functions of the amboceptor. Considering 

 that the normal amboceptors and those produced by immunization 

 are essentially similar (a point which we have always emphasized), 

 it is perfectly obvious that one can produce the same antiamboceptors 

 by immunizing with normal amboceptors. Hence what Bordet's 

 study really brings forward is the actual experimental demonstration 

 of what we had long expected was the case. 



Naturally we were able to confirm all of Bordet's statements of 

 fact. We had at our disposal the serum of a goat which had been 

 immunized with normal rabbit serum, and could easily convince 

 ourselves that this serum acts as an antiamboceptor against ambo- 

 ceptors derived from rabbits by specifically immunizing with o*x 

 blood. Furthermore, we succeeded, by adding the antiamboceptor 

 to previously sensitized blood-cells, to protect these against haemolysis 

 by complement. The antiamboceptor acts just like a complementoid 

 according to the conception of "complementoid-blocking" described 

 by one of us some time ago. 1 It occupies the complementophile 

 groups and so prevents the anchoring of the complement. 2 



only to the antibodies directed against the cytophile groups, since it is to be 

 assumed that these cytophile groups, which have their natural counter-groups 

 in bacterial cells, will not have these in the cells of higher animals. This limi- 

 tation, however, does not apply to the antiamboceptors acting on the comple- 

 mentophile complex. This, then, disposes of Bordet's objections to this point. 



1 Ehrlich and Sachs, "Uber den Mechanismus der Amboceptorenwirkung. 

 Berl. klin. Wochenschrift, No. 21, 1902. 



2 We must not fail to mention that, in contrast to Bordet, we made these experi- 

 ments without the addition of inactive guinea-pig serum, and were able, despite 



