l8o LOCAL TLSSUE REACTIVITY 



a distinct hemorrhagic reaction. Cultures of the fluid of the edem- 

 atotis tissues ^\ere sterile. It is ohxious that these authors must 

 have dealt with a xaccinia \irus lesion, the severity of which was 

 probably enhanced by the presence of the testicidar tissue (Rey- 

 n^ils factors) and by the possible primary injinious effect of the 

 B. coll cultme filtrate in the mixture. The appearance of the 

 hemorrhage three days after the intradermal injection observed 

 in severe vaccinia lesions of the dermis make it impossible to con- 

 sider these ol)servations as having any relationship whatsoever to 

 the phenomenon of local skin reactivity. The possible formation 

 of new princij)les residting from the provocative injection, of 

 coinse, is not excluded by the failure of its demonstration. There 

 is some other suggestive evidence in favor of this hypothesis which 

 will be discussed in a sid^sequent chapter. The other possibility 

 still remains, however, that the direct effect of the active prin- 

 ciples upon the endothelial elements of the l^lood vessels made 

 reactixe by the intradermal preparatory injection, may play an 

 important role in the mechanism of the phenomenon. 



Bock (1932) made a very interesting observation xvhich needs 

 further in\'estigation. According to this author, of 7 rabbits pre- 

 pared with bacterial filtrates and subse([uently injected into the 

 left heart, 2 showed a very xveak reaction and 5 were negative. 

 Of 7 rabbits injected into the right heart, 2 showed a weak re- 

 action and 5 showed a severe positive reaction. This author notes 

 that the possible explanation of this obserxation lies in the fact 

 that the injections made into the right heart pass first through 

 the lungs. He questions Avhether the limgs play any activating 

 role in the phenomenon of local skin reactixity to bacterial fil- 

 trates. 



H. Gross (1931^, b, c) attempted a reverse order of injections, 

 i.e., preparatory injections xvere given intraxenotisly, subcutane- 

 otisly, intramuscularly and intraperitoneally. These injections were 

 follox\ed twenty-four hours later by an intracutaneous injection of 

 the active principles. His restdts xvere consistently negative. 



In my own experiments 25 units of B. typJiosiis reacting factors 

 were injected intravenotisly in some groups of rabbits, and in 

 others, the same amount xvas injected intracranially. Immediately 

 afterwards, and six hours later, the rabbits received an intrader- 

 mal injection of the potent material. Intravenous or intracranial 

 injections given simultaneoidy xvith the intradermal injections 

 yielded reactions in a small percentage of rabbits. As xvill be 



