JOINT ACTION OF SEVERAL AMBOCEPTORS. 



635 



is already itself bound by the prepared ox blood. It can, however, 

 be shown that the active principle of the ox serum loses none of its 

 power by digestion with prepared ox blood-cells. From this it 

 follows that the view just discussed, wherein the ox serum is regarded 

 as acting as a complementoid, is incorrect. 



It was necessary to cast about for other explanations, and it was 

 natural to think that in the haemolysis of the prepared ox blood too, 

 the inactive ox serum possessed direct relations to the horse serum. 

 We had noticed that the ox serum amboceptor acting on guinea-pig 

 blood possessed a marked affinity for horse complement. This fact 

 suggested that the ox serum could produce anticomplementary 

 effects, for it is readily understood that an amboceptor possessing 

 affinity for the complement will act like an anticomplement when the 

 suitable blood-cells are absent. As a matter of fact we have shown 

 (see Table VII) that large amounts of inactive ox serum hinder the 

 ha3molysis of the prepared ox blood. This inhibition can only be 

 due to anticomplement action. These findings naturally led us to 

 suspect that the inactive ox serum and the horse serum were in 

 some way related to one another in the production of the hsmolytic 

 effect. We therefore proceeded as follows: 



In one series of tubes decreasing amounts of horse serum were kept for 

 one hour at 37, whereupon prepared ox blood plus 0.5 cc. inactive ox serum 

 were added. In another series decreasing amounts of horse serum were digested 

 for one hour with 0.5 cc. inactive ox serum at 37 whereupon the blood-cells 

 were added. The degree of haemolysis was noted from time to time, and is 

 is shown in the following table: 



TABLE X. 



