BACTERIOLYSIS AND ALLIED PHENOMENA 159 



presence of complementoids in test-tube experiments, and this 

 was owing to the fact that the affinity of the haptophore group of 

 the complements suffered loss during the process of heating, so 

 that when a mixture of complement and complementoid was 

 added to sensitized red corpuscles, the former combined just as 

 well as if the latter were not present. " Blocking " of the com- 

 plementophile group of the amboceptor appeared not to occur ; 

 but Ehrlich and Sachs were able subsequently to demonstrate 

 such a phenomenon in this wise : Dog serum contains an ambo- 

 ceptor for guinea-pig's corpuscles, and this can be activated either 

 by dog's or guinea-pig's serum. Now when a mixture of heated 

 dog's serum, guinea-pig's corpuscles, and guinea-pig's serum was 

 made, solution took place ; but when the corpuscles and heated 

 serum were added together, allowed to stand, and then centrifuga- 

 lized and removed, no solution occurred on the addition of fresh 



FIG. 40. DEMONSTRATION OF " BLOCKING " OF COMPLEMENTOPHILE GROUPS 

 BY COMPLEMENTOIDS. 



a = complementoid, and = amboceptor in heated dog serum; r=:rabbit's 

 corpuscles (see text). 



guinea-pig's serum. Ehrlich proved 1 that the combination of 

 amboceptor and corpuscles took place as usual, and that it was then 

 followed by a blocking of the free arms of these amboceptors by 

 the complementoids present in the heated dog's blood. In this 

 case, therefore, the complement had not suffered any appreciable 

 change in combining capacity as a result of its conversion into 

 complementoid. 



It follows, therefore, that when we heat fresh serum, or allow it 

 to stand a few days at the room temperature, we do not get rid 

 of the complements altogether. This can be done, as shown by 

 Von Dungern and others, by shaking the serum with cells (liver, 

 kidney, etc.), yeast, fungi, certain bacteria, powdered charcoal, 

 etc. This abstraction of complements by inert bodies is a non- 

 specific process entirely unlike its fixation in haemolysis, etc., 



1 The proof is complete and conclusive, but too long to give here. 



