198 TOXINES AND ANTITOXINES. 



But the name amount of antitoxins was required after the 

 experiment as before to neutralise the greatly reduced agglutinat- 

 ing power, as well as the unaltered toxic activity. One c.c. of 

 antitoxine was required to neutralise the extraordinarily small 

 agglutinating power of 5 c.c. of pepsin-ricine ; but the same 

 quantity was also sufficient to destroy the toxic activity of the 

 same quantity corresponding to at least 15 mgrms. of ricine (30 

 lethal doses). But, more than that, it was possible still to add 

 enormous quantities of poison (up to 8 c.c. of pepsin-ricine) 

 without killing the animals, though they certainly became 

 emaciated. 



One is strongly reminded by these facts of the conditions 

 observed in the case of bacterial toxines, especially those of 

 tetanus and diphtheria. There, too, EHKLICH found that more 

 than a single lethal dose had to be added to a completely neutral 

 mixture (L ) in order to obtain L + (see the value D in the 

 General Part). 



Another very interesting result was shown by JACOBY'S ex- 

 periments viz., that whereas 1 c.c. of antitoxine was required 

 to neutralise O26 c.c. of ricine solution before the treatment with 

 pepsin, the same quantity was sufficient for 5 c.c. after the treat- 

 ment. At the same time the toxic action remained unchanged, 

 so that any possible destruction of the ricine molecules was out 

 of the question. 



It surely follows from these experiments that a large number 

 of the haptophore groups must have disappeared, which, in the 

 untreated ricine, had combined with the receptors of the serum, 

 but, subsequently, no longer had any attraction for the anti- 

 ricine. But these haptophore groups could not have corresponded 

 with the toxophore groups, since the toxic power remained un- 

 changed. We are thus inevitably driven to the conclusion that 

 non-poisonous haptophore groups must have been present in the 

 crude ricine. JACOBY is thus justified in his conclusion that 

 there are ricine toxoids which are destroyed by pepsin-hydrochloric 

 acid. And they must also be syn- or protoxoids^ since they are 

 simultaneously saturated on neutralisation. 



The conditions are quite the reverse in the case of the 

 agglutinating function. It is true that the number of hapto- 

 phore groups also shows a decrease here, but to a smaller extent 

 than that of the ergophore groups. If, now, we assume that the 

 haptophore groups are the same, it is probable that there are 

 here formed new toxoids of a peculiar kind, which consist of only 

 the haptophore and toxophore group, and have lost their ayglutino- 

 phore group. 



