REACTIVITY TO VARIOUS MICROORGANISMS 41 



were found by me to yield active principles ot the phenomenon. 

 No end-point titrations of the materials were made at the time. 

 Siiwartzman (\c)2Sa) , and Hanger (1928/;) employed filtrates of 

 se\enty-two iiour old broth cultures of B. lepiscpticus. These fil- 

 trates gave a strong primary reaction, apparently dtie to a state 

 of hypersensitixeness to B. Icpisepticiis in the rabbits employed 

 by this atithor. Intravenous injection of the same filtrates inten- 

 sified the primary reactions. Hanger states emphatically that he 

 ne\er observed this phenomenon except among rabbits natu- 

 rally allergic or rendered allergic by a previous infection. Al- 

 thotigh his report appeared folloxving my publication on the phe- 

 nomenon of local skin reactivity to bacterial filtrates and his 

 experiments with this preparation xvere made according to the 

 technicjue described in my paper, the above statement makes it 

 questionable xvhether Hanger's material derived from B. Icpi- 

 septicus contained the active principles of the phenomenon (pos- 

 sibly because of the use of plain broth) . It is indeed clear that 

 there exists no relationship between the allergic state of the ani- 

 mal and its ability to respond to the phenomenon of local skin 

 reactivity to bacterial filtrates. It suffices to mention here that 

 with some preparations, i.e., meningococcus, the reactions may 

 be obtained in 100 per cent of rabbits, as judged by experiments 

 on many thousands of these animals. Moreover, no stich depend- 

 ence on the allergy of the animals was observed by P. Boquet 

 (i9'^5) in his successful attempts at reproducing the phenomenon 

 with B. lepisepticus. This author grew the organism in Martin 

 bouillon for six days and filtered the culture through infusorial 

 earth and Chamberlain L^ filters. Rabbits were prepared by an 

 intradermal injection of 0.5 c.c. of the filtrate and tested by an in- 

 travenous injection of 2 c.c. per kilo of body weight. Yoiuig cul- 

 tures were inactive. If cultures were heated at 50° c. for one hoiu' 

 before filtration, the filtrates appeared to be of a higher potency. 

 The filtrates apparently contained both preparatory and provoca- 

 tive factors. Combined intradermal injection of the B. lepisep- 

 ticus filtrate with the intravenotis injection of B. coli filtrate or 

 a combined preparatory injection of B. coli filtrate w'lxh provoca- 

 tive injection of B. lepisepticus filtrate also yielded positive 

 results. 



Apitz (i935«) employed a strain of B. pasteurella cuniculicida 

 which somexvhat differed from Hanger's strain of B. lepisepticus. 

 The author emphasizes the fact that in his experiments intracu- 



