PROTEIN SENSITIZATION OF ANAPHYLAXIS 287 



and in all cases its poisonous group is at some stage of the 

 process activated as it were. If it were not for the fact that 

 the poisonous group is not readily diffusible through animal 

 membranes, and especially through the walls of the alimen- 

 tary canal, all proteins would be poisonous to us even when 

 taken by the mouth, because the protein poison is set free 

 in alimentary digestion, but not being readily diffusible, it is 

 split up and rendered inert as digestion proceeds. When, 

 however, digestion is parenteral, escape from the effect 

 of the protein poison is impossible, and the ultimate effect 

 upon the organism is determined wholly by the amount ren- 

 dered active at one time. When it is set free with explosive 

 rapidity and in relatively large amount it induces anaphyl- 

 actic shock, and possibly death. When set free slowly and 

 in small amount, we have fever or fall in temperature, 

 according to the amount of the poison liberated. When set 

 free either in the circulating fluid or when it passes into 

 this fluid immediately we have systemic effects. When 

 set free locally we have inflammation in the adjacent 

 tissue. Narrowly used the term anaphylaxis refers to the 

 symptoms of anaphylactic shock. In a wider sense it 

 covers all the phenomena of parenteral protein digestion. 

 Some think that parenteral digestion is always abnormal, 

 either artificially induced or due to pathological conditions. 

 We doubt the truth of this assumption. By inhalation, 

 through abrasions and possibly through the alimentary 

 canal, man must be frequently, almost constantly, taking 

 into his blood and tissues very minute traces of undigested 

 proteins, but ordinarily the amounts thus taken in are so 

 infinitesimally small that the body cells are not sensi- 

 tized, and no harm comes. While, as we have seen, some 

 anaphylactogens sensitize in very small doses, these are not 

 infinitesimal, and there are measurable doses which do not 

 sensitize. The limits vary with the protein and the animal. 

 Friedemann and Isaac, 1 also Pfeiffer and Mita, 2 think 



1 Zeitsch. f. exp. Path., 1905, i, 513; 1906, ii; 1908, iv, 830, 



2 Zeitsch. f. Immunitatsforschung, 1909, iv. 



