The Antagonism between Toxins and Antitoxins. 421 



Behring. Ehrlich, and Kanthack being principal exponents of the 

 direct chemical view, whilst Buchner, E/oux, and Metchnikoff: still 

 maintain that the interaction takes place only through the interven- 

 tion of some cells in the body. 



We will briefly review the more important observations which bear 

 directly upon the subject of our paper. 



(1) Observations favouring the Interpretation that the Action of 

 Antitoxins is indirect. 



Calmette* in 1895 made experiments with the toxin of cobra poison 

 and its antitoxin, which he had recently succeeded in producing. 

 Cobra poison is not apparently attenuated by heating its solutions to 

 68 C. for ten minutes. The antitoxin is, however, completely de- 

 stroyed by this treatment. Mixtures of cobra poison and antitoxin 

 which produced no symptoms when injected into a rabbit, killed 

 similar rabbits in a few hours if after the mixture had remained in 

 contact for ten minutes it were heated for another ten minutes to 

 68 0. before injecting. From his experiments Calmette concluded 

 that the toxin of snake venom does not interact with its antitoxin in 

 vitro, but only in corpore, and therefore that its action cannot be 

 explained as a simple chemical operation between the two. 



Wassermannf found that the toxin produced by the bacillus pyo- 

 cyaneus was not destroyed by boiling, whereas its antitoxin was. 

 The amount of toxin and antitoxin which neutralised each other was 

 first determined by experiment, then the same quantities and propor- 

 tions of these substances were allowed to remain in contact and 

 afterwards heated to boiling. The animals receiving an injection of 

 this heated mixture died, whereas the control animals which received 

 an equal dose unheated recovered. From these experiments Wasser- 

 mann concluded that the toxin of pyocyanens does not interact with 

 its antitoxin in vitro, but only in corpore, and therefore that it cannot 

 be explained as a simple chemical operation between the two. 



Nikanorow { discovered that the precipitate formed by the addition 

 of a 1 per cent, solution of cupric acetate was possessed of antitoxic 

 properties and the filtrate not. A 1 per cent, solution of cupric 

 acetate does not, however, precipitate the toxin. Mixtures of the two 

 could thus be separated by the use of this reagent. Experiments 

 conducted along the lines mentioned in the experiments above led to 

 identical results. 



Marenghi made some observations with the toxin and antitoxin 



* Ann. de 1'Inst. Pasteur,' 1895, p. 250. 



f ' Zeits. f. Hyg.,' 1896, B. 22, p. 263. 



t ' Wratsch,' 1896, vol. 31, abstracted ' J. Ph. Chem.,' 1896, p. 983. 



< Centralbl. f. Bakt.,' 1897,' vol. 22, p. 521. 



