ANTITOXINES. 27 



has shown that toxoids of tetanus poison which have become 

 quite non-poisonous no longer induce the formation of antitoxine. Accord- 

 ing to his views, when side-chains are broken off there must be present in 

 addition to the haptophore group a certain "combining ring" derived 

 from the toxophore group. 



Toxones are not absolutely innocuous, but eventually produce 

 temporary symptoms of poisoning (paralysis, &c.), which, how- 

 ever, are absolutely different in kind from the effects of small 

 doses of toxines. 



Toxoids have been identified with certainty in the case of 

 diphtheria (EHRLICH), of tetanolysine (q.v.) (MADSEN) and of 

 staphylotoxine (NEISSER and WECHSBERG, q.v.), and JACOBY (loc. 

 cit.) has shown that in all probability they accompany ricine. 



There is also, however, a considerable weight of evidence that 

 some at least of the other bacterial poisons have the power of 

 producing secondary toxoids, in the case of tetanus, for example, 

 to which we shall return in the special part. 



VAN CALCAR 2 succeeded in separating the toxones from the toxine by 

 taking advantage of the fact that animal membranes stretched to a certain 

 extent allow the toxine to pass, but not the toxones. Hence, toxones 

 have a greater molecular volume than toxines. When the membrane was 

 stretched to a greater extent the toxones also diffused through it. 



This is the extent of our knowledge of toxoids and toxones. 

 Since they, too, are specific haptines, they also produce anti- 

 toxines as MADSEN and DREYER 3 succeeded in demonstrating in 

 the case of diphtheria toxones. 



MADSEN and DREYER were also able to prove the existence 

 of toxones which were poisonous to rabbits, but without action 

 upon guinea-pigs. A poison that was without action upon 

 guinea-pigs after neutralisation in the ratio of 200 : 200, did not 

 become innocuous to rabbits until the ratio of the neutralising 

 antitoxine reached 240 : 200. EHRLICH has given the name 

 " toxonoids " to this variety of poison. 



On Antitoxines in General. Our definite knowledge of anti- 

 toxines is even smaller than our knowledge of toxines. 



They occur in the fluids of the body, notably in the blood 

 serum and milk of immunised animals. Slight traces are also 



, "Beitr. z. Theorie d. Immunitat," Zeit. f. Hyg., xlvi., 176, 

 1904. 



2 Van Calcar, "Ueb. die Constit. des Diphtheriegiftes," Berl. klin. 

 Woch., 1904, No. 39. 



3 Madsen and Dreyer, "Ueber Imrnun. mit den Toxonen d. Diphtherie- 

 giftes, Zeit.f. Hyg., xxxvii., 249, 1901. 



