372 INFECTION AND IMMUNITY 



bination with the serum proteins of the host, which are then so 

 altered in their antigenic properties that they can act as antibody 

 inciting or, in other words, antigenic substances. When horse serum 

 or other animal sera for instance are treated with iodin, an iodin- 

 protein combination is formed, which represents an antigenic altera- 

 tion of the original serum protein. Animals injected with such an 

 iodized horse serum will produce antibodies which are, to some 

 extent, specific for this iodin-protein combination. It is not impos- 

 sible that this is the fundamental basis for drug allergy, but there are 

 very strong arguments against this assumption, particularly the 

 failure up to date to produce such conditions uniformly in animals 

 by active or passive sensitization. It would seem to us futile at the 

 present time to make either positive or negative statements in this 

 respect. 



ANAPHYLAXIS IN INFECTIOUS DISEASE. There can be little doubt 

 about the fact that both general and localized hyper sensitiveness 

 play an important role in infectious disease. Whenever an infection 

 becomes subacute or chronic, the body may become sensitized to the 

 coagulable protein in the bacterial body. This we have ourselves 

 shown with typhoid protein, and with tuberculous guinea pigs and 

 tuberculo-protein ; and, in the case of tuberculosis, our experiments 

 done with the Dale method corroborated the previous experiments 

 of Baldwin, 60 Krause 61 and others who worked by the intravenous 

 method. Thus, in all infectious diseases which last any length of 

 time, we can count upon anaphylactic phenomena to participate in 

 the general symptomatological and pathological picture. This sub- 

 ject is still very much a matter of experimental investigation, and 

 a discussion of it would carry us too far afield in the present 

 connection. 



Delayed skin reactions, like the typhoidin, tuberculin, etc., reac- 

 tion, are, we believe, phenomena of specific sypersensitiveness to 

 substances of a somewhat less complex molecular structure than the 

 proteins, substances which do not produce antibodies in the usual 

 sense; these substances are more diffusible than are the true pro- 

 teins, can get inside the cells, and their reaction with the cells, 

 then, is an intracellular one in which the intervention of sessile 

 antibodies is not necessary. For a further analysis of this relation- 

 ship and the experimental basis for the statements we make, we refer 

 the reader to our unpublished article mentioned above. 



"Baldivin, J. Med. Kes., 119, 1910. 



61 Krause, Amer. Eev. Tuber., 1, 1917, 65. 





