4 QUATERCENTENARY STUDIES IN PATHOLOGY 



Wassermann also made special inquiry into the existence of a 

 pyocyanic toxin, which he obtained by growing cultures of the bacillus 

 for about six weeks, at the end of which time he destroyed the vitality 

 of the culture by means of toluol. Such toluolised cultures were highly 

 toxic, killing guinea-pigs rapidly in a dose of '5 c.c. Even with young 

 toluolised cultures, he obtained evidence of toxic effect, and, as the bodies 

 of pyocyanic bacilli killed with chloroform were much less toxic, he 

 concluded that in the broth there must be a specific pyocyanic toxin. 

 The toxin was not entirely robbed of its toxic properties by heating 

 to 115^ C. 



In his immunisation experiments Wassermann found great differences, 

 according as the animals were injected with the pyocyanic toxin or with 

 the bacilli themselves. In the former case the serum protected against 

 both the toxin and the culture, whereas the serum of animals, 

 immunised with bacilli, protected only against the bacilli, but was 

 unable to neutralise the lethal effect of the toxin. In most cases the 

 immunised animals (guinea-pigs) could withstand many times the lethal 

 dose of the living cultures, but only small multiples of the lethal toxin 

 dose. As had been shown by Pfeiffer and Kolle in the case of cholera 

 and typhoid, it was not possible to raise the immunity to an unlimited 

 degree. 



The nature of the immunity induced was also studied by Wasser- 

 mann, and although he was unable to demonstrate any bactericidal 

 powers in the immune serum in vitro, he found that in vivo the pyocyanic 

 bacillus is destroyed in the peritoneal fluid, the destruction being 

 accomplished without the agency of leucocytes. He considered that the 

 process was similar to that which obtains in the case of typhoid and 

 cholera. To the sera of animals immunised with increasing doses of 

 pyocyanic toxin he ascribed true antitoxic properties. 



Working along the same lines as Wassermann, Gh^orghiewsky (4) 

 obtained divergent results, in so far that he found the pyocyanic bacillus 

 to be taken up by the phagocytes in the peritoneal cavity, and destroyed 

 in their interior. 



When a non-lethal dose of bacillus pyocyaneus was introduced into 

 the peritoneal cavity of a normal guinea-pig, there was a definite 

 leucocytosis at the end of two to three hours, and within six hours all the 

 injected bacilli were engulfed by the leucocytes, in the interior of which 



(160) 



