XXXVI. THE ISOLATION OF SNAKE VENOM 



LECITHIDS. 1 



By Dr, PRESTON KYES, Instructor in Anatomy, University of Chicago, Fellow 

 of the Rockefeller Institute for Medical Research. 



SPECIAL interest attaches to the study of snake venoms be- 

 cause of the analogy which exists between their peculiar character 

 and that of bacterial toxins. All investigators who have worked with 

 this subject have been struck by this analogy, and Phisalix 2 has dis- 

 cussed it in a special monograph. The analogy between snake venoms 

 and bacterial toxins consists, above all, in the fact that neither are 

 crystallizable, that their constitution is unknown, that both are 

 highly virulent specific products of poison-forming cells, and both 

 possess the power to excite the production of- antibodies in the 

 organism. This last fact we know from the fundamental researches 

 of Calmette. 3 



A further analogy between snake venoms and the toxins is the 

 fact that the poisonous properties of both are destroyed by heat, 

 and that the non-toxic substance thus formed is able to excite the 

 production of antibodies just as well as the original substance. In 

 other words, in both poisons there is a formation of toxoid. Snake 

 venom has accordingly played an important role in the theoretical 

 doctrine of immunity. Martin and Cherry, 4 for example, by their 

 well-known filtration experiment were able to prove that snake venom 

 and specific antitoxin unite to form a new non-poisonous combination. 

 This experiment is based on the principles first formulated by Ehrlich 



1 Reprint from the Berliner klin. Wochensch. 1903, Nos. 42 43. 



2 Phisalix, Etude comparee des toxines microbiennes et des venins, L'Annee 

 biologique I, 1895. 



3 Calmette, Ann. de 1'Institut Pasteur, No. 5, 1894. 



' Martin and Cherry, Proceedings of the Royal Society, Vol. LXIII. 1898. 



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