236 MICROBES AND TOXINS 



months (experiments of Otto, Rosenau and Anderson, 

 Besredka). 



Anaphylaxis to Cells. Animals injected with red 

 corpuscles, washed (to prevent the action of the serum) or un- 

 washed, resist the first injection well but support a second 

 badly. 



Similarly with bacterial cells, typhoid, paratyphoid bacilli, 

 etc., they present more or less severe symptoms after the 

 second injection. The specificity of this reaction does not 

 appear to be very strict. This variety of anaphylaxis is of 

 great practical importance for in the preparation of anti- 

 plague sera it is necessary to inject the cultures into the 

 jugular vein of horses, and severe symptoms are quite 

 common. 



Organ Extracts. The phenomena induced by injections 

 of extracts of spleen, lymphatic glands, bone marrow, or 

 spermatozoa are analogous to the preceding. The supersensi- 

 tive state can be induced towards extracts of the crystalline lens 

 of the eye and an animal thus prepared reacts only towards the 

 lens tissue, no matter from what species of animal, even when 

 it presents no reaction to the serum of that animal. 



A tuberculous patient becomes supersensitive to the product 

 of the tubercle bacillus, to tuberculin. But in this case it 

 appears that only the disease itself can induce this excessive 

 susceptibility permanently : it is very doubtful if it can be 

 produced by the injection of the bacterial bodies or of 

 tuberculin. Physiologically speaking it is an anaphylactic 

 phenomenon. 



Passive Anaphylaxis. M. Nicolle has shown that if a 

 fresh rabbit is given a large dose of the serum of a rabbit 

 rendered anaphylactic to horse serum, the fresh rabbit takes on 

 an anaphylaxis which is therefore called passive. It may in its 

 turn present the typical symptoms on injection 24 hours after the 

 preparatory injection. This brief delay shows that it is a true 

 passive anaphylaxis, and not an active anaphylaxis induced by 

 small quantities of horse serum which might have remained in 

 the serum of the sensitive rabbit. This experiment demon- 



