BACTERIAL POISONS 47 



bits and guinea pigs, but showed further that the brains of chickens, 

 animals that are but moderately susceptible, possess a correspond- 

 ingly slighter neutralizing power, and, further, that brain tissues of 

 entirely insusceptible cold-blooded animals, turtles and frogs, pos- 

 sess absolutely no neutralizing properties. 



The original interpretation by Wassermann of these facts was 

 based on the assumption that the poison was bound to the brain tissue 

 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 tiie 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, ^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- 



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



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

 61 Muller. Centralbl f. Bakt., Vol. 34, 1903. 



62 Landsteiner. Wien. kl. Rimdschau, 13, 1905. 



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



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



