BACTERIOLOGY IN A NUTSHELL. 



Tetanus 



Toxin 



Af&nity. 



plete neutralization in the test tube, while it 

 has been shown by the experiments of others 

 that the affinity of tetanus toxin for the nervous 

 tissues is very strong, all the toxin being 

 absorbed in a few minutes. These facts dem- 

 onstrate that the curative value of the tetanus 

 serum must be low. On the most vital of all 

 organs, the central nervous system and the 

 spinal cord, the tetanus toxin has proven to 

 have marked selective action. For this reason 

 a lower grade of injury may prove fatal in this 

 disease than in other infections where less im- 

 portant organs (or those of greater recupera- 

 tive power) are affected. The theory that the 

 tetanus toxin is "taken up by the nerve endings 

 and reaches the ganglionic cells by way of the 

 axis cylinder, where it is in a manner isolated 

 and is scarcely accessible to the action of the 

 antitoxin (which remains, for the most part, 

 after injection, in the blood and lymphatic cir- 

 culation), has given place to the belief that the 

 reason for failure in the use of tetanus serum 

 is probably due to the powerful affinity of 

 tetanus toxin to the cells of the spinal cord. The 

 damage is done before the antitoxin can be 

 administered. In accidents in the laboratory, 

 where enormous quantities of pure cultures 

 have gotten into open wounds, the prompt 

 adminstration of serum has prevented develop- 

 ment of the toxemia. 



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