626 



COLLECTED STUDIES IN IMMUNITY. 

 TABLE V. 



The table shows that haemolysis is actually more rapid when 

 horse serum and inactive ox serum are first allowed to remain in 

 contact for a time. During this time the ox amboceptor and horse 

 complement have entered into combination, and the period of 

 incubation preceding haemolysis is thus shortened. Moreover, 

 as can be seen from the table, the final hamolytic effect may also 

 be somewhat greater when ambloceptor and complement are first 

 digested together. The reason for this evidently lies in a slight 

 impairment of the horse complement as a result of the one hour's 

 heating to 37, the combination of ox amboceptor and horse com- 

 plement evidently being more resistant. It need hardly be men- 

 tioned that these results are incompatible with the colloid theory. 



If we could remove the amboceptors of horse serum it would 

 be possible to demonstrate directly the amboceptor role played 

 by the ox serum. It is well known that a method devised by Ehr- 

 lich and Morgenroth 1 enables us to separate the amboceptor and 

 complement of an active serum. Thus, by digesting red blood- 

 cells at with an active serum, it will be found that only ambo- 

 ceptor has been bound; the complement remains in the fluid. In 

 the case of the normal ha3molysins, to be sure, a difficulty arises 

 from the fact that the binding of amboceptor at is usually in- 

 complete, some of the amboceptor remaining unbound. So in 

 the case of the amboceptors of horse serum, we know from the work 

 of Browning that at guinea-pig blood-cells bind them only up to 



1 Ehrlich and Morgenroth, Berliner klin. Wochenschr., 1899. See also this 

 volume, page 1. 



