STUDIES ON ANTIAMBOCEPTORS. 651 



Moreschi, 1 that "the anticomplementary action of the precipitate 

 may counterfeit the existence of antiamboceptors." 



Using an amboceptor derived from a human convalescent from 

 cholera, Pfeiffer and Friedberger 2 found that bacteriolysis could 

 be inhibited by a rabbit serum obtained by immunizing a rabbit 

 with human serum. They concluded from their experiments that 

 the possibility of this being an antiamboceptor action could be ex- 

 cluded. It must be pointed out, however, that the results permit 

 of another explanation. In the first place Pfeiffer and Moreschi 

 believe it highly improbable that the antiserum obtained by immun- 

 izing with normal human serum should contain cholera antiambo- 

 ceptors. This assumption is wholly unwarranted. We have already 

 called attention to Bordet's observation that by immunizing with 

 a normal serum one obtains antiamboceptors against all the ambo- 

 ceptors of the same species. These antiamboceptors, being directed 

 against the complementophile group, are in their action entirely 

 independent of the cytophilic specificity. The fact, therefore, that 

 the normal (human) serum used for immunization contains no 

 cholera amboceptors, does not in any way argue against the existence 

 of cholera antiamboceptors. 



So also with the main experiment cited by Pfeiffer and Moreschi. 

 This does not necessarily show the absence of antiamboceptors, 

 even though it does show the antibacteriolytic action produced by 

 the union of complement and precipitate. Pfeiffer and Moreschi 

 employed an antiserum derived from rabbits by immunization with 

 human serum. When human cholera serum was used as amboceptor, 

 in testing the precipitates and the supernatant fluids, they found 

 that the precipitates exerted an antibacteriolytic action, while the 

 supernatant fluid had no such action. From the conception of anti- 

 amboceptors furnished by Bordet's experiments, it might very well 

 be that the antiamboceptors contained in the antiserum had been 

 neutralized by the amboceptors present in the normal human serum 

 used for precipitation. So far as the specific cholera amboceptors 

 are concerned, these amboceptors accordingly have acted as "anti- 

 antiamboceptors," and being so combined, their action as ambo- 

 ceptors is excluded. . All that can be claimed for this experiment, 

 therefore, is that it demonstrates the antibacteriolytic action of the 



1 Pfeiffer and Moreschi, Berliner klin. Wochenschr. No. 2, 1906. 



2 Pfeiffer and Moreschi (?) [Translator]. 



