564 



ANAPHYLAXIS 



vitro with excised muscle (uterus) for the identification of the protein 

 substances, such as blood-stains. Guinea-pigs sensitized with human 

 serum will react best with human serum, and to a lesser extent with 

 that of the higher apes, but not at all with the serum of the dog, ox, or 

 fowl. Wells and Osborne, 1 working with purified vegetable protein, 

 were able to demonstrate that a single isolated protein (hordein or 

 gliadin) may contain more than one antigenic radical, and that not the 

 whole protein molecule, but certain groups thereof, determine the 

 specificity. Wells 2 was able to distinguish in the hen's egg five dis- 

 tinctly different antigens, and these corresponded to five proteins that 

 were isolated by chemical methods, so that it would appear that the 

 specificity of the anaphylaxis reaction is determined by the chemical struc- 

 ture of the reacting proteins, rather than by their biologic origin. Whether 

 the chemical differences that determine specificity are of quantitative 

 nature, or whether they are sometimes dependent upon the number and 

 relationship of the amino-radicals, as was suggested by Pick, remains 

 to be determined. 



1 Jour. Infect. Dis., 1913, 12, 341. 2 Jour. Infect. Dis., 1911, 9, 147. 



