160 THEORIES CONCERNING IMMUNITY 



state of immunity-anaphylaxis ; and even if these differences 

 are not usually sufficiently pronounced to interfere with 

 ordinary biological experiments, they do exert a decisive 

 influence on secondary and distant reactions. 



To these differences of "diathesis" must be attributed the 

 different pathologic manifestations observed in the case of 

 rabbits injected with horse serum. For the same reason 

 injections of arsenobenzene will cause gastro-intestinal dis- 

 turbances in certain individuals, dermatoses or arthritides 

 or nervous disturbances in still others or perhaps all these 

 symptoms at the same time; while in the majority of cases, 

 there will be no apparent reaction. 



It is solely by the state of previously acquired immunity- 

 anaphylaxis that one can explain the idiosyncrasies, predis- 

 positions or hypersensitiveness of individuals to foreign 

 proteins of all kinds, to drugs, to certain smells, to changes 

 in temperature and to emotions. So that when one meets 

 these same morbid states manifesting themselves chronically 

 without any apparent immediate cause, the idea forces 

 itself of its own accord that these diseases can have but one 

 origin, a preexisting state of immunity-anaphylaxis. 



In order, therefore, to find a biological method of treating 

 these diseases in conformity with the conception of the 

 specificity of "sensitizing" and "shocking" antigens, it is 

 necessary, above all, to search for the antigen which is the 

 primary cause of the disease, and which may be different in 

 each particular case. 



That a definite susceptibility to foreign proteins existing 

 in the form of dust and with w f hich the patient comes in 

 contact through the respiratory tract, as well as in the form 

 of food which is ingested, may be responsible for a certain 

 number of chronic states has recently been discovered. 



The literature contains many reports of these cases and such 

 diseases as hay fever, asthma, urticaria and eczema should 

 always be studied with the possibility of such a foreign pro- 

 tein sensitiveness in mind. The studies of Goodale, 1 Long- 



1 Diagnosis and Management of Vasomotor Disturbances of the Upper 

 Air Passage, British Med. and Surg. Jour., 1916, clxxv, 181. 



