CHAPTER VI 

 THE PROBABLE MECHANISM OF THE REACTION 



In discussing the theories proposed to explain the mechanism of 

 the therapeutic processes which we are calling into play when non- 

 specific therapy is used, it will be well for the moment to dismiss 

 the rigid conception of antibody immunity that has been built up on 

 the researches of Ehrlich and the contemporary French and English 

 workers, not because it is unimportant, rather because of the com- 

 plication that it introduces. Antibody immunity is a vital factor 

 in protection against infectious disease and in overcoming actual 

 bacterial infection. In the nonspecific reaction the therapeutic benefit, 

 however, seems largely independent of the specific antigen-antibody 

 balance. The fact that we do not discuss the antibody theory in 

 this connection should not give the impression that it is to be ignored 

 as a factor of defense and of resistance. 



Intoxication by Protein Split Products. Antibody resistance has 

 been studied most completely in connection with the neutralization of 

 the specific soluble toxins that are secreted by certain bacteria, notably 

 the diphtheria bacillus, tetanus bacillus, etc. But we are beginning to 

 take greater cognizance of the fact that in dealing with bacterial in- 

 toxication we have to do with other and less clearly defined toxic sub- 

 stances, broadly termed endotoxins to designate the fact that they 

 form an integral part of the bacterial body. Some of these are possibly 

 native proteins to which the infected organism can become sensitized, 

 while others may be primarily toxic to the infected organism without 

 previous sensitization. We must also consider: (a) Preformed protein 

 split products which are toxic. This toxicity may be due to particular 

 molecular grouping as the native protein molecule is broken up in 

 the normal metabolism of the bacterial cell or to the chemical con- 

 figuration of the fragments; those containing the benzol ring with 

 its various addition radicals being most toxic (Baehr and Pick), 

 (b) Protein split products formed as the bacterial protein is frag- 

 mented in the host after the bacterial cell has died, i.e., not neces- 

 sarily preformed in the bacterium, (c) Toxic growth products derived 

 from the bacterial metabolism and excreted, (d) Toxic metabolic 

 products derived from the pathologic cellular metabolism of the in- 

 vaded organism (Jobling and Petersen, Zimmermann, etc.). In all 

 these enumerated sources of toxic material derived either from the 



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