82 IMMUNE SERA 



up of different partial-immune bodies, then we must 

 admit that we have better chances for finding fit- 

 ting complements if we make use of immune bodies 

 derived from a variety of animals. We would, for 

 instance, be likely to achieve better results in treat- 

 ing a typhoid patient with a mixture of specific 

 bactericidal typhoid sera derived from a variety of 

 animals than if we used a serum derived only from 

 a horse. For in such a mixture of immune bodies 

 the variety of partial-immune bodies must be very 

 great and the chances that the complements of the 

 human body will find fitting immune bodies, and so 

 lead to the destruction of the typhoid bacilli, are 

 greatly increased. Ehrlich and his pupils have 

 actually proposed such a procedure in the use of 

 bactericidal sera for therapeutic purposes. 1 



Support for Ehrlich' s View. Besides the above 

 experiments we possess others which support the 

 theory that the immune body is not a simple but 

 a compound substance, v. Dungern had alre&dy 

 shown that following the treatment of an animal 

 with ciliated epithelium from the trachea of an c x, 

 there were developed immune bodies which act 3d 

 not only on the ciliated epithelium but also on tie 

 red cells of oxen. We must assume, therefore, th it 



1 Reasoning along similar lines, namely, that the hurr in 

 complement must fit the immune body of the therapeutic 

 serum, Ehrlich has also proposed that these bactericidal s.;ra 

 be derived from animals very closely related to man, e g., 

 apes, etc. 



