364 PROTEIN POISONS 



phenomena of so-called antianaphylaxis, but he admits 

 that rapid digestion in this state may be prevented by the 

 accumulated products of digestion. He says: "From recent 

 studies we know that the ferment forms a compound with 

 the substrate before the equilibrium of the latter is destroyed. 

 After the cleavage the ferment is again free, so far as it is 

 not bound by the cleavage products." It seems to us that 

 this is all that is necessary to explain the known facts in 

 so-called antianaphylaxis. 



In his work on the digestive action of blood serum Abder- 

 halden has largely employed polypeptids and purified 

 peptones. Of course, he does not expect these denatured 

 proteins to act as sensitizers and lead to the development 

 of specific ferments, but they are especially suited for diges- 

 tive experiments, because the split products as soon as 

 formed are easily recognized by their effect on the rotation 

 of light. In this way he has shown that peptones and poly- 

 peptids are quickly split into their constituent amino-acids 

 by the proteolytic ferment normally present in serum. In 

 other instances he has employed native proteins as sensi- 

 tizers. In one case he divided a lot of guinea-pigs sensi- 

 tized to egg-white into three .groups. The members of 

 the first group while in the sensitized state were bled, and 

 the serum thus obtained was digested with egg-white, and 

 it was demonstrated both by dialysis and the optical method 

 that the egg-white was digested by the serum. Now, had 

 this been done with the serum of normal guinea-pigs there 

 would have been no recognizable digestion. It must follow, 

 therefore, so far as we can see, that the blood-serum of the 

 sensitized guinea-pig contains a ferment which is not 

 present in the blood-serum of the fresh guinea-pig. Further- 

 more, had it been tried, it would have been found that the 

 blood-serum of the guinea-pig sensitized to egg-white would 

 either have no digestive action, or but slight effect, on other 

 proteins. It follows, therefore, that the sensitized animal 

 differs from the unsensitized in the fact that its body cells 

 elaborate a specific ferment which digests the protein by 

 which it was called into existence, and no other. It will, 



