368 INFECTION AND IMMUNITY. 



tive power of the cells; hence, antitoxin cures by 

 tearing from the cells, perhaps not all, but so much 

 of the toxin that less than a fatal dose remains in 

 the cell. 



"pr?nl ^ e ma y ^ earn f rom the experiments of Donitz 

 dpies. and of Madsen two important principles of anti- 

 toxic therapy : First, that of early administration, 

 i. e., before a fatal amount of toxin has been 

 bound, and, second, the necessity of injecting suffi- 

 cient quantities of antitoxin. 



The comparative study of diphtheria and tet- 

 anus has clarified the principles of antitoxic 

 therapy to no small degree. Knowing that diph- 

 theria antitoxin has a much greater curative value 

 than tetanus antitoxin, we find some conditions 

 which would seem to explain the difference, at 

 least in part. 



Tetanus. In regard to tetanus we have the following 

 facts: In the test-glass the affinity between the 

 toxin and antitoxin is rather weak, since approxi- 

 mately forty minutes are required for complete 

 neutralization (Ehrlich). On the other hand, the 

 experiments of Donitz and of Heymans show that 

 the affinity of the toxin for nervous tissue is ex- 

 ceedingly strong, all the toxin being taken up 

 within a few minutes. These two conditions alone 

 suggest the probability of a low curative value on 

 the part of the serum. The toxin of tetanus also 

 has a remarkable selective action on the most vital 

 of all organs, the central nervous system; hence, a 

 lower grade of injury may prove fatal than in 

 other infections in which less important organs or 

 those of greater recuperative power are involved 

 chiefly. Furthermore, it seems (Meyer and Ean- 

 som, Marie and Morax) that the tetanus toxin is 



