TOXIC ACTION OF COMPLEMENTS 85 



The chief results may be summarized as follows : 



1. In the action of a complement there are two distinct 

 factors, viz. (a) power of chemical combination, and (6) toxic 

 action, corresponding to the ' haptophore ' and the ' zymo- 

 toxic ' groups of Ehrlich ; deficiency in the action of com- 

 plement (or in ' complementing ') does not necessarily 

 imply want of combining affinity, but may be entirely due 

 to the non-sensitiveness of the tissue-molecule to the zymo- 

 toxic group. 



2. In the ca'se of the three hsemolytic sera studied, the 

 outstanding fact is the large dose both of immune-body 

 and of complement necessary when we use the complement 

 of the same species of animal as that whose corpuscles are 

 being tested. 



3. In all three cases there is a relative non-sensitiveness 

 of the corpuscles of the animal to the zymotoxic group of 

 its own complement ; hence a large dose of immune-body 

 is requisite to bring into combination the amount of com- 

 plement necessary for haemolysis. In one case (that of the 

 ox) there is also a deficiency in the combining power of the 

 complement with the receptors of the red corpuscles united 

 to immune-body ; from the two conditions acting together 

 complete haemolysis cannot be obtained. 



4. Although differences among the molecules of the same 

 immune-serum may occur, we have found no evidence that 

 the striking differences in the dosage of the immune-body 

 with different complements, and also in the dosage of various 

 complements, are due to the multiplicity of immune-bodies. 



No one has yet succeeded in producing an anti-substance 

 or immune-body by injecting an animal with its own cor- 

 puscles or cells such a body as with the aid of complement 

 would produce destruction of these cells. This is mani- 

 festly a provision against self-poisoning, and Ehrlich has 

 applied to it the term autotoxicus horror. The results which 

 we have brought forward, if they were found to hold 



