6 QUATERCENTENARY STUDIES IN PATHOLOGY 



Heating to I20°C. in the autoclave did not rob the toxic substance 

 of nnuch of its toxicity. Maclntyre failed to produce immunity to intra- 

 peritoneal injection by a previous series of subcutaneous inoculations. 



In his most recent publication on the subject of pyocyanic immunity, 

 Wassermann (9) still maintains the distinction between the antitoxic and 

 bactericidal properties of the immune serum ; although he admits that 

 the antitoxin does not, as in the case of other antitoxins, follow the law 

 of multiples. He explains this by assuming that the pyocyanic 

 " toxin," in addition to the true exotoxin, contains endotoxin which 

 has dissolved out of the bodies of the bacilli. The bactericidal action 

 he still holds to be similar to that which obtains in the case of cholera, 

 although the extra-cellular destruction of the B. pyocyaneus is slow 

 compared with that of the vibrio cholerae. 



Experimental. 



Four races of bacillus pyocyaneus were used in the following experi- 

 ments, and they were isolated from the throat, an ulcer of the leg, from 

 the blood, and from the intestine respectively, of human beings. In all 

 cases the cultures were highly pathogenic for guinea-pigs, and less so for 

 rabbits. 



When freshly isolated, one loopful of an agar culture injected into the 

 peritoneum of a guinea-pig killed the animal acutely within 12 hours, the 

 autopsy revealing intense peritonitis with great desquamation of endo- 

 thelium, and accumulation of leucocytes in the thick fibrinous exudate. 

 Minute haemorrhages were numerous on the mesentery. The liver and 

 kidney, on microscopic section, showed evidences of severe cloudy 

 swelling. Cultivations from peritoneal exudate, liver, and heart blood, 

 showed that the bacillus had become generalised over the body, the 

 condition being really a pyocyanic septicaemia. 



Cultures from the heart blood were inoculated into large flasks 

 containing 3-6 litres of i % peptonised bouillon, and grown for periods 

 varying from two days to three months. Within twenty-four hours a fine 

 bacterial film appears on the surface, and within three or four days it has 

 become converted into a thick membrane. The flasks were then 

 thoroughly shaken, so as to dislodge the membrane to the bottom. As 

 soon as a new membrane appeared, the process was repeated. When 

 the flasks were kept untouched in the incubator for three to four weeks, 



(162) 



