ioo IMMUNE SERA 



red cells of oxen. We must assume, therefore, that 

 the ciliated epithelium and the red cells of the ox 

 possess common receptors. Analogous to this is 

 the action of the immune body resulting from the 

 injection of spermatozoa, as was pointed out by 

 Metchnikoff and Moxter. 



We see, then, that the specific action of immune 

 bodies is not so limited as to apply only to the cells 

 used in the immunizing process, but extends to 

 other cells which have receptors in common with 

 these. The same holds good for the agglutinins 

 and the precipitins still to be studied. In these 

 the action extends also to closely related cells 

 and bacteria, or in the . case of the precipitins 

 to closely related albumins, as these possess a 

 number of receptors which are common to them 

 and to the cells or substances used for immuniz- 

 ing. 



So far as concerns the site in the organism where 

 the substances used in immunizing find their 

 receptors, this is not known for the hasmolytic 

 immune body. For the bactericidal immune bodies 

 of cholera and typhoid the researches of Pfeiffer, 

 Marx, and others show that the chief site of pro- 

 duction is in the bone-marrow, spleen, and lymph 

 bodies. Wassermann's experiments on local immu- 

 nity indicate that the site of infection determines 

 largely the site of the development of the immune 

 bodies. 



