118 TOXINES AND ANTITOXINES. 



calling attention to the work of MARX, 1 who has resurveyed the 

 whole ground. 



MARX has found, by over 200 experiments on mice, that the 

 antitoxic action of the brain is of such a nature that it is merely 

 supplemented by the addition of serum, and that the action of 

 the brain does not, as was found by KITASHIMA (loc. cit.) in ex- 

 periments with very large amounts of toxine, destroy the action 

 of the antitoxine. 



MARX thus confirms W ASS ERM ANN'S view that the combined 

 receptors of the brain act qualitatively and quantitatively in a 

 completely analogous manner to the free receptors that are 

 present in the antitoxine serum. 



And this affords a fresh support of EHR LICK'S view that 

 the poison can only combine with suitable receptors, and that 

 these receptors, when broken off, have a neutralising effect upon 

 the poison, although they promote its action when acting in 

 conjunction with living cells. 



It is impossible to see the force of the objection first brought 

 against these experiments viz., that the brain of animals, such 

 as hens, &c., that are only slightly susceptible, has no protective 

 action for it is self-evident to anyone who bases his conclusions 

 on the fundamental axioms of Ehrlich's theory, that only such 

 nerve substance as actually combines with the tetanus toxine 

 i.e., possesses suitable haptophore groups can exert a protective 

 influence ; and such haptophore groups are evidently only present 

 in the brains, &c., of these animals, which indeed are not refrac- 

 tory, not naturally immune to tetanus. It is thus one of the 

 most striking results of Ehrlich's theory that it at once throws 

 a clear light upon the formerly so inscrutable problem of natural 

 immunity. Both infection and the relative formation of anti- 

 bodies can only take place where there is a reciprocal combination 

 of haptophore groups. Where these are lacking there can be 

 absolutely no infection or neutralisation of the poison. 



Indeed, the central nervous system is not the exclusive place 

 where the antitoxine can be produced. As we have mentioned 

 above, receptors that can combine with the poison also occur in 

 other places where the fixation of the poison does not lead to 

 any injurious effects e.g., in the connective tissue, &c. But 

 wherever receptors are present, there, too, can the formation of 

 antitoxine take place. The production of antitoxine is a function 

 of the haptophore group, and has absolutely nothing to do with 

 the action of the poison as such. Thus, according to EHRLICH 



1 Marx, "Die Tet.-G. neutralis. Eigensch. d. Gehirns," Zeit. f. Hyg., 

 xl, 231, 1902. 



