28 PROTEIN POISONS 



20. The sensitization developed by a protein is specific, 

 but is not due to the poisonous group in the protein. As we 

 have stated, the specificity of a protein is not due to its 

 poisonous group, which is much the same in all proteins, 

 but to its secondary groups, for it is in these that one protein 

 differs from all others. 



21. Different proteins find in the body certain predilection 

 places in which they are most prone to accumulate. The 

 pneumococcus accumulates in the lungs, the smallpox 

 virus in the skin, the typhoid bacillus in the spleen, and 

 mesenteric glands; the tubercle bacillus finds its most 

 frequent location in the lungs, but it has been a parasite 

 so long that it may grow on any human tissue. 



22. The symptoms of a given disease are largely determined 

 by the location of the foreign protein. The most skilful 

 physician may not be able to tell what organism is respon- 

 sible for a meningitis. The symptoms of acute miliary 

 tuberculosis and those of typhoid fever are much alike. 

 It is the location of the infection rather than the exact 

 nature of the infecting agent which gives rise to the more 

 or less characteristic symptoms of the several infectious 

 diseases. 



23. The poison, elaborated in all the infectious diseases is 

 the same. It is the protein poison, and it is physiologically 

 the same whatever its source, whether it comes from coccus, 

 bacterium, spirillum, or protozoan. The specificity which 

 characterizes the infectious diseases is not due to the poison 

 formed, but to the protein cause and the specific ferment 

 produced. 



24. When- a cell in the animal body is permeated by a 

 foreign protein, the former strives to elaborate a ferment by 

 which the latter is destroyed. We believe this to be a biological 

 law, and we think that it lies at the foundation of a correct 

 understanding of many of the problems of immunity and 

 disease. 



