MECHANISM OF THE ACTION OF ANTI AMBOCEPTORS. 575 



results. The plurality of amboceptors is further demonstrated by 

 the results of the isolysin experiments published by Ehrlich and 

 Morgenroth, 1 for in these experiments the presence of antibodies 

 acting against the complementophile group of the amboceptor can 

 be excluded. The fact that we have drawn an incorrect conclusion 

 from one single experiment, certainly does not justify Bordet in deny- 

 ing the existence of a plurality of antibodies (especially amboceptors) 

 in a given immune serum ; the correctness of our view is established 

 by a number of incontestable experiments. 



Bordet's arguments concerning deflection of complement by an 

 excess of amboceptor may be answered in the same manner. Even 

 granted that Morgenroth's view 2 is incorrect, namely, that the inhibi- 

 tion of hremolysis on the addition of an amboceptor-antiamboceptor 

 mixture is due to a deflection of complement, this would not in the 

 least refute the results obtained by Neisser and Wechsberg with 

 bactericidal sera. In these experiments absolutely no antiambo- 

 ceptor is present; there are merely bacteria, amboceptor, and comple- 

 ment. Despite this, however, there is no bactericidal action when a 

 certain excess of amboceptor is present. The only explanation for 

 this is the one offered by Neisser and Wechsberg, 3 namely, that the 

 complement is deflected from the amboceptor combined with the 

 cells by the free amboceptor. This explanation has also been accepted 

 by Lipstein, 4 who controverted a number of objections which had 

 been made by various authors. Bordet does not even attempt to 

 controvert our explanation, but contents himself by saying: " Pour 

 nous, la theorie de la deviation du complement par Pambocepteur 

 est une legende." Needless to say this will have little effect on our 

 view. 



It is thus seen that Bordet's recent experiments have furnished 

 additional important confirmation of the amboceptor theory. Analysis 

 of the antiamboceptor action clearly demonstrates the fact that the 

 amboceptor possesses other affinities besides those of the cytophile 

 group; and the circumstance that the occupation of these groups 

 bars the action of the complement shows that they are complemento- 

 phile in character. Bordet's attack on the receptor theory has thus 



1 Ehrlich and Morgenroth, Third Communication. See page 23. 



2 J. Morgenroth, 1. c. 



3 M. Neisser and Wechsberg. See page 120. 



4 A. Lipstein, Centralblatt t'vir Bacteriologie, 1902, Vol. 31, No 10; see also 

 page 132 of this volume. 



