48 LOCAL TLSSUE REAC^TIVITY 



\iiulciu loi iiiicc. At the tiiiic it was employed for the experi- 

 ments, as fe\v as 100 organisms were al)le to kill a mouse \vithin 

 three days Avheii iiijeeted intrajieritoiieally. Filtrates ot virulent 

 cidtures in glucose broth and in brain medimn also gave active 

 ]:»reparati()ns ^\■hi(h elicited reactions in ajjproximately 75 j)er (eni 

 ol rabbits prexiously prepared by intradermal injection of a po- 

 tent heterologous filtrate. Although no systematic studies were car- 

 ried out, the casual impression was that the high viriUence of the 

 strejitococcus strain employed ^vas not necessarily respcjnsible for 

 production of actixe filtrates, inasmuch as fdtrates oi the same 

 organism at the time when its virtdence xvas considerably reduced 

 also yielded active princij^les. 



The various streptococcus preparations completely lacked skin- 

 preparatory factors. 



Reactions with indifferent and green-producing streptococci : 



These experiments may be conveniently divided into three 

 groups, i.e., 1. Streptococcus materials trsed both for preparatory 

 and provocative injections. 2. Heterologous potent bacterial fil- 

 trates used for preparatory injections and streptococcus materials 

 for provocative injections. 3. Streptococcus preparations used for 

 preparatory injections and ]:)otent heterologoirs filtrates for pro- 

 vocati\'e injections. 



The first grouj) embodied experiments Avith six strains of en- 

 terococcus isolated from the blood stream of rheinnatic fever 

 patients (Lichtman and Gross, 1932) . 



Tryptic digest ])roth in amoimts of 100 c.c. xvas placed in 500 

 c.c. Erlenmeyer flasks. The medium was inocidated xvith the re- 

 spective strains of enterococcus and incid^ated for six days. The 

 cultures were centrifuged and filtered throtigh Berkefeld "V" 

 candles. Rabbits w^ere prepared each Ijy foiu^ simidtaneous injec- 

 tions of the inidiluted material into the skin of the abdominal 

 wall. Twenty-four hotirs later, the same iUtrates were injected 

 intravenously in a dose of 3 c.c, per kilo of body xveight. About 

 75 per cent of rabbits developed strong typical reactions at the 

 sites prepared. Some rabbits gave weak reactions. The response 

 Avas the same in all foiu^ sites prepared in strongly, as well as 

 weakly reacting animals. Preparations obtained from plain broth 

 four day old culttnes also gave consistently positive residts. The 

 materials were not titrated to the end-point and, therefore, no 



