BACTERIAL POISONS 47 



just as it is bound to antitoxin. Experiments by Besredka 59 have 

 cast some doubt upon this. This worker's experiments seem to indi- 

 cate that a brain emulsion which has been saturated with the toxin 

 can be rendered capable of absorbing more toxin if tetanus antitoxin 

 is mixed with it. In other words, the affinity of the antitoxin for the 

 toxin is stronger than that of the brain substance for the poison, and 

 that the union toxin-brain tissue is very easily dissociated ; as indeed 

 it should if the union were purely a physical one depending on solu- 

 bility. 



After it had been shown that the poisons which acted specifically 

 upon certain cells were actually taken up by these cells, a number of 

 attempts were made to determine chemically the tissue element 

 which united with the poisons, l^oguchi 60 showed that cholesterin 

 and alcoholic extracts of blood serum neutralized tetanolysin. The 

 same thing was later shown by Miiller, 61 and Landsteiner 62 showed 

 that ether extracts of red blood cells likewise neutralized this poison. 

 In a later study by Landsteiner and von Eisler 63 the relation of the 

 tissue lipoids to various toxic substances was still more definitely 

 established. They studied first the various hemolysins and found 

 that extraction of blood cells with ether rendered the stromata less 

 capable of binding the hemolytic substances. The same thing they 

 showed for bacteriolysins, in the latter case demonstrating at the 

 same time that the ether extracts of bacterial bodies possessed slight 

 binding properties for the bactericidal substances of the serum. These 

 experiments have, of course, a merely indirect significance in the 

 present connection, since they do not deal with the type of poisons 

 we have discussed. However, Landsteiner and von Eisler also 

 worked with tetanus toxin and found that the treatment of the brain 

 substance of guinea pigs with ether, by taking out lipoidal sub- 

 stances, considerably reduces the power of this tissue to bind and 

 neutralize the tetanus poisons. 



Takaki, 64 who investigated these relations in great detail, iso- 

 lated an alcohol-soluble element, cerebron, from nerve tissues, a sub- 

 stance to which he ascribes the toxin-binding properties. Overton 

 and Bang 65 found, furthermore, that cholesterin and lecithin inhibit 

 the action of cobra venom, a poison which is in so many ways similar 

 to those produced by bacteria. Taking into consideration all avail- 

 able evidence, we are forced to admit that the lipoids seem to play an 

 important role in determining the selective action of the nervous sys- 



59 Besredka. Ann. Past., 1903, p. 138. 



60 Noofuchi. Univ. Pa. Med, Bull, Nov., 1902. 

 11 Miiller. Centralbl. f. Bakt., Vol. 34, 1903. 



52 Landsteiner. Wien. kl Bundschau, 13, 1905. 



63 Landsteiner and von Eisler. Centralbl. f. Bakt., 39, p. 318, 1905. 



14 Takaki. Beitr. zur chem. Phys. u. Path., 11, No. 19, 1908. 



65 See Ivar Bang, "Biochemie der Lipoide," Bergman n, Wiesbaden, 1911. 



