PRODUCTION OF ANTITOXIN 411 



tetanus was capable, when injected into other animals, of protecting 

 them not only against poisoning with tetanus toxin but also against 

 infection with living tetanus bacilli. They also proved that, under 

 certain conditions, a curative action could be demonstrated in animals 

 which already presented symptoms of tetanus infection. Similar, 

 though less striking, results were described in the case of diphtheria. 

 The next step was to isolate these substances, and separating 

 them from the blood, investigate still further their constitution. 

 A number of workers were soon occupied at this task, and 

 Buchner, Hankin, the Klemperers, Eoux, Sidney Martin, and 

 others have added to our knowledge respecting these toxin- 

 opposing bodies now known as antitoxins. Some believed these 

 bodies were a kind of ultratoxin substances of which an early 

 form was a toxin ; others held that, as the toxins were products of 

 the bacteria invading the tissues, the antitoxins were of the nature 

 of ferments produced by the resisting tissues. A third view is that 

 possibly antitoxins may be the result of an increased formation of 

 molecules normally present in the tissues. Finally, antitoxins came 

 to be looked upon as protective substances produced in the body cells 

 as a result of toxic action, and held in solution in the blood, and 

 there and elsewhere exerting their influence in opposition to the 

 toxins. These antitoxic bodies gradually increase in the blood and 

 tissues, and their action falls into two groups : (a) antitoxic, which 

 counteract the effects of the poison itself; and (b) antimicrobic, 

 which counteract the effects of the bacillus itself. "In one and 

 the same animal the blood may contain a substance or substances 

 which are both antitoxic and antimicrobic, such, for example, as 

 occurs in the process of the formation of the diphtheria and 

 tetanus antitoxic serums " (Sidney Martin). Antitoxin must, 

 therefore, be looked upon as a normal constituent of the living 

 cells which is produced in increased quantity. Of the chemical 

 nature of toxins and antitoxins, very little is known. Martin 

 and Cherry have come to the conclusion that toxins are prob- 

 ably of the nature of albumoses, and antitoxins probably have 

 a molecule of greater size, and may be allied to the globulins. 

 Antitoxin has been shown to appear in the various secretions 

 of the body as well as in the blood, though in a less concentrated 

 state. 



The relation of the antitoxin to the toxin, and its mode of 

 antagonism, is probably one analogous to chemical union. The two 

 bodies unite to form an inert compound possessing no toxic or 

 pathogenic effect. It is found that a definite period of time elapses 

 before the effect of the toxin is neutralised, and that it takes place 

 more rapidly in strong solutions than in weak, and in warm 

 temperature than in cold, which all goes to confirm the view that 



