XI, B, 1 Ruediger: H hemolysis by Human Serum 49 



The natural antirabbit amboceptor remained nearly inactive 

 when 0.05 cubic centimeter of guinea pig complement serum 

 was used; larger quantities of guinea pig serum reactivated 

 the amboceptor well. 



Guinea pig serum is slightly haemolytic for rabbit corpuscles. 



Guinea pig complement, even when used in large doses, does 

 not readily reactivate the natural antihorse amboceptor. This 

 amboceptor can be readily reactivated with human complement. 



Guinea pig complement does not reactivate the natural anti- 

 guinea pig amboceptor. 



Natural antiguinea pig amboceptor can readily be reactivated 

 with human complement. 



Natural antiguinea pig amboceptor is easily removed from 

 human serum. 



Natural antihorse amboceptor is not easily removed from 

 human serum. 



Fresh, unheated human serum left in contact with guinea pig 

 corpuscles for more than three hours loses the power to reac- 

 tivate the antiguinea pig amboceptor. 



Natural antihorse amboceptor can be removed from human 

 serum without disturbing the natural antiguinea pig amboceptor. 



Natural antiguinea pig amboceptor can be removed from hu- 

 man serum without disturbing the natural antihorse amboceptor. 



140085 4 



