424 INFECTION AND RESISTANCE 



tually yielded such results. Thus Neufeld and Dold obtained 

 poisons by digesting typhoid bacilli, cholera spirilla, and other 

 micro-organisms for several hours in salt solution, lecithin salt solu- 

 tion, and inactivated guinea pig sera. Their extracts killed guinea 

 pigs within several hours. Rosenow 37 has even succeeded in obtain- 

 ing acutely toxic substances which caused typical anaphylactic death 

 in guinea pigs by suspending pneumococci, typhoid bacilli, and other 

 bacteria in salt solution at 37 C. for varying periods, and the 

 writer, 38 though never producing acute death, was able to cause 

 typical anaphylactic shock in isolated cases with similar salt solution 

 extracts of typhoid bacilli. It is not impossible that poisons obtained 

 in this way are formed by autolysis due to proteolytic enzymes of 

 the bacterial cell. 



In cases in which bacteria, suspended in salt solution and other 

 indifferent fluids, represent the only source of protein present it 

 must, of course, be assumed that they are the substratum or matrix of 

 the anaphylactic poison. They are also, of course, to be regarded as 

 the source of the poison in such experiments as those of Vaughan, in 

 which the poison was produced by chemical hydrolysis of the bac- 

 terial bodies. In the case of anaphylatoxin production by fresh 

 serum in the presence of bacteria, kaolin, precipitates, etc., the ques- 

 tion is much more complex. 



As we have stated before, it is only natural, considering our pre- 

 vious knowledge of bacteriolysis in serum, that the first conclusion 

 arrived at should look for the source of the poisons in the bacterial 

 cells. The doubt which has been cast upon this assumption by the 

 work of Keysser and Wassermann and others, however, rests upon a 

 sufficiently sound experimental basis to prevent our absolute accept- 

 ance of this view. Jobling and Peterson 39 have recently carried out 

 experiments which may serve to throw much light upon anaphyla- 

 toxin. They believe that, by the ordinary technique of anaphylatoxin 

 production with bacteria and serum, most of the toxic substances orig- 

 inate from the serum proteins. The bacteria act merely by remov- 

 ing the antiferments from the serum, thereby setting free the fer- 

 ments normally present in the serum, and permitting them to act 

 upon the serum proteins. The result is cleavage and the production 

 of toxic split products. This would explain such results as those of 

 Keysser and Wassermann. Jobling and Peterson have supported 

 their contention by experiments in which they have obtained typical 

 anaphylatoxins by removing serum antiferments with chloroform, 

 kaolin, and agar. They have further shown that emulsions of bac- 

 teria actually do remove antiferments from fresh serum, and that 



37 Rosenow. Jour. Inf. Dis., Vol. 9, 1911; Vol. 10, 1912. 



38 Zinsser. Loc. cit. 



89 Jobling and Peterson. Jour, of Exp. Med., June, 1914. 



