BACTERIAL INVASION 219 



in the text, the splanchnic stasis which is so character- 

 istic of cytost action appears to involve the agglutina- 

 tion of blood cells, it may be that the agglutinating 

 efifect of minute quantities of cytost is greatly magni- 

 fied by the adsorption of the latter on various blood 

 colloids or upon bacteria, vs^hich in many respects be- 

 have as colloids. 



In agreement with this concept, it was found that 

 a similar potentiation of tissue extracts containing cy- 

 tost could be achieved by admixture with a dilute 

 agar-agar suspension. That is, if, by preliminary as- 

 say one ascertains the maximal quantity of a potent 

 cytost preparation which may be injected into an ani- 

 mal without the production of any noticeable evi- 

 dence of toxicity, and then injects this quantity of cy- 

 tost in admixture with a small quantity of a dilute 

 solution of agar-agar, the symptoms of shock are 

 found to follow immediately. 



This finding strengthens our contention that the 

 role of the colon organism in the experiments cited 

 above is essentially that of a colloid which, by adsorp- 

 tion of the cytost, markedly potentiates the latter. This 

 is of considerable interest, since it opens the way to a 

 possible explanation of the interesting mysteries of 

 the well known phenomena of anaphylaxis and ana- 

 phylactic shock. As is well established, these promptly 

 follow the injection of a foreign protein into the cir- 

 culation of any animal which, some weeks previously, 

 has received a sensitizing dose of the same protein. 

 Various ingenious hypotheses have been advanced 

 to explain this puzzling phenomenon, but as yet no 

 single theory has been found capable of accounting 

 for all the known facts of anaphylaxis. 



