220 THE ACTION OF THE LIVING CELL 



Whereas we cannot offer a comprehensive theory 

 of anaphylactic reactions, the experiments cited above 

 indicate that such a theory should include a recogni- 

 tion of the possible role of cytost in such reactions. In 

 this connection it may be imagined that the initial or 

 sensitizing dose of protein, bacterial or otherwise, 

 brings about in some fashion the liberation of cytost in 

 an amount sufficient to cause shock when adsorbed 

 upon an appropriate colloid. Then the parenteral 

 introduction of the second or intoxicating dose of the 

 protein may furnish the necessary surface for the ad- 

 sorption of and consequent potentiation of the cytost. 

 This hypothesis does not account for the well known 

 specificity of anaphylactic reactions, is necessarily 

 vague, and is offered merely as a suggestion for the 

 consideration of those interested in this field of inves- 

 tigation. 



The essential point is that regardless of the mechan- 

 ism of anaphylactic shock, it seems to be ordinary 

 shock, such as we have discussed at some length, which 

 is brought about in an indirect fashion involving the 

 foreign protein introduced into the circulation of an 

 animal. This fact has been recognized by Zinsser 

 (1931) in his recent discussion of anaphylaxis. He 

 calls attention to the fact that the typical symptoms 

 of anaphylactic shock may be elicited by a variety of 

 injuries which can have nothing in common with a 

 true anaphylactic reaction. Zinsser suggests that the 

 reason for this may be that the union of the antigen 

 and its specific antibody on the surface of the body 

 cells causes a surface injury similar to that brought 

 about by trauma or other means. 



From the above discussion it should be clear that 



