166 TOXINES AND ANTITOXINES. 



Yet even his results are open to question, inasmuch as it has 

 been found by SCHKNK (loc. cit.) that O5 per cent, of phenol is 

 also insufficient to kill all the micro-organisms. He found that, 

 although the cultures were apparently sterile, there were yet 

 some living micro-organisms in the blood of the heart of the 

 poisoned animals, so that it is quite possible that PARASCANDALO 

 produced immunity by means of isolated, weakened, but yet 

 living streptococci. SiMON, 1 too, was only able to detect the 

 production of toxine after the decomposition of the cells. Thus 

 proof has yet to be brought of the existence of streptotoxine, and 

 the question is as open as that of gonotoxine. 



THE POISON OF THE TUBERCLE BACILLUS. 



The poisonous substances produced by the bacillus of tubercu- 

 losis require separate treatment for the following reasons : In 

 the case of other poison-producing bacteria the true toxines, or 

 rather those specific poisons that it is possible to describe with 

 more or less certainty as of the nature of toxines, can be 

 separately described and differentiated from the so-called bac- 

 terial proteins, in the wider sense, that remain behind in the cells 

 of the bacilli themselves after the extraction of these poisons 

 which the micro-organisms have produced. This sharp differen- 

 tiation is not possible on historical grounds in the case of tuber- 

 culosis, for since the time when the poisons of the tubercle 

 bacillus were first seriously studied, it has been the almost 

 invariable practice to investigate both kinds of poisons without 

 separating them. 



The first preparations of tubercle poison, and notably R. Koch's 

 tuberculine, were thus a mixture of all the specific and non-specific 

 poisonous products of this bacillus, and no investigation was made 

 to determine the question of the existence of a true toxine. At 

 that time, too, it was not possible to formulate the question in 

 such precise terms, since the definition of a true toxine, and of 

 the true antitoxic immunity that it involved, had not then been 

 given with sufficient clearness. 



These toxic preparations, therefore, consisted of the more or 

 less altered substances of the cell itself. In addition to these, 

 however, they also undoubtedly contained other toxic products, 

 some of which possibly we must regard as primary secretion 

 products, and eventually as true toxines, and others as secondary 

 products of a simpler nature, with which we shall also deal later. 



1 Simon, "Uber die Gifte der Streptococcus," CentralU.f. BaTct., xxxv., 

 318, 1904. 



