COMPLEMENTS 251 



an animal, the animal's blood will contain amboceptors for 

 the cell used and also for others closely related to it. Immun- 

 ization with spermatozoa or with epithelial or liver cells gives 

 rise to amboceptors for these cells and also for red blood 

 corpuscles and other body cells. A typhoid bactericidal 

 serum has also some dissolving effect on colon bacilli, etc. 

 Hence a given serum may contain a chief amboceptor and a 

 variety of "coamboceptors," or one amboceptor made up 

 of a number of "partial amboceptors" each specific for its 

 own antigen ("amboceptorogen"). Amboceptors may com- 

 bine with other substances than antigen and complement, as 

 is shown by their union with lecithin and other "lipoids," 

 though these substances seem capable of acting as comple- 

 ment in causing solution of blood corpuscles. 



COMPLEMENTS. 



As to whether complements are numerous, as Ehrlich 

 claims, or there is only one complement, according to Bueh- 

 ner and others, need not be discussed here. In the practi- 

 cal applications given later as means of diagnosis it is appar- 

 ent that all the complement or complements are capable of 

 uniting with at least two kinds of amboceptors. 



If complement be injected into an animal it may act as 

 an antigen and give rise to the formation of anticomplement 

 which may combine with it and prevent its action and is 

 consequently analogous to antitoxin. If amboceptors as 

 antigen are injected into an animal there will be formed by 

 the animal's cells antiamboceptors. As one would expect, 

 there are two kinds of antiamboceptors, one for each of its 

 combining groups, since it has been stated that it is always 

 the combining group of any given antigen that acts as the 

 cell stimulus. Hence we may have an " anticytophil ambo- 

 ceptor" or an "anticomplementophil amboceptor." These 

 antiamboceptors and the anticomplements are analogous to 

 antitoxin, antiagglutinin, etc., and hence are receptors of 

 the first order. 



