XIII. ON THE MODE OF ACTION OF ANTITOXINS 

 ON TOXINS.* 



BY DR. JULES BORDET. 



The majority of scientists who have studied antitoxins believe 

 that they modify the poison for which they are the antidote. In 

 other words, antitoxin protects the animal, not by rendering it more 

 resistant, but by reacting with the toxin and destroying its harm- 

 ful properties. 



This conclusion has been drawn from numerous important re- 

 searches, among which may be mentioned those of Martin and 

 Cherry. Its accuracy became very evident as soon as we were 

 able, thanks to Ehrlich, to eliminate experiments on the living 

 animal, with the accompanying uncertainty of individual varia- 

 tion, and replace them by cells that are susceptible to the poison. 

 Thereafter we were able to study the effect of antitoxin on toxin 

 in vitro, as the sensitive cell is changed when toxin is present, but 

 remains intact if this poison has been neutralized by a suitable dose 

 of antitoxin. 



The conception that antitoxin not only modifies toxin, but that 

 it also unites with it, is in perfect harmony with the data we have 

 concerning the other active substances of sera, and may therefore 

 be accepted with relative certainty. The action resembles closely 

 the effect produced by agglutinins, sensitizers and alexin on sus- 

 ceptible cells; in a similar way the precipitins, which are strikingly 

 analogous to the agglutinins, agree to a certain extent with true 

 antitoxins in that they unite with non-differentiated chemical 

 substances. 



Since we may regard it as proven that antitoxin destroys the 

 harmful properties of toxin by direct combination, an attempt may 

 be made to determine the intimate reaction between these two 



* Sur le mode d'action des antitoxines sur les toxines. Annales de 1'Institut 

 Pasteur, XVII, 1903, 161. 



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