QO IMMUNE SERA 



tors in the rabbit serum whose haptophore group 

 fits to their own. 



Fluctuations in the Amount of the Active Sub- 

 stances in Serum. As already said, we have thus 

 far been unable to show that the complements of an 

 organism are decreased through the action of spon- 

 taneously formed anticomplements. We have, 

 however, come to know certain conditions under 

 which there may be a decrease of certain comple- 

 ments in normal serum. Ehrlich and Morgenroth 

 showed that in rabbits poisoned with phosphorus 

 and in whom, therefore, the liver was badly damaged, 

 the serum on the second day (the height of the 

 disease) had lost its power to dissolve guinea-pig 

 blood, and that this was due to a disappeareance of 

 the complement. Metchnikoff also reported that in 

 an animal suffering from a continuing suppurating, 

 process, the complement had fallen considerably in 

 amount. Especially interesting are the experi- 

 ments of v. Dungern, who showed that animal cells, 

 hence emulsions of fresh organs, are able to attract 

 and combine with complements. 



Even more important than the question of a 

 decrease in complements, or an inhibition of their 

 action, is that of the possibility to artificially in- 

 crease them. A number of authors, among them 

 Nolf and Miiller, have answered this question in the 

 affirmative. They believe they have noticed such 

 an increase following the injection of an animal with 



