REACTnilY TO VARIOUS MICROORGANISMS 45 



Actixe principles were ol)tained l)y these authors from strains of 

 Group 1 and 2 (cholera \ibrio) , Grotip 3 (xvater vibrio) , and 

 Group 4 (El Tor \'ibrio) . There xvere obserxed, howexer, (jnan- 

 titative differences in the amotmt of active principles obtained 

 from xarioiis strains. The El Tor \ ibrio consistently gave small 

 size reactions xvhen used for skin preparation. The latter filtrates 

 employed intraxenotisly gave rise to sizable reactions only at sites 

 prepared xvith J'ibrio cholerae filtrates of the other strains. 



ACTIVE PRINCIPLES OF STAPHYLOCOCCUS 



Bin net (1931) , Gratia and Linz (i932r) , and myself failed to 

 elicit the phenomenon of local skin reactixity to filtrates of plain 

 broth and "agar washings" of staphylococcus. 



H. Gross (1932) studied the primary necrotizing effect of sta- 

 phylococcus filtrates previously described by Lingelsheim, Neis- 

 ser and Wechsberg, Kraus and Pribram, and H. Gross, Parker, 

 and Burnet (1929, 1930) . In these tests lixe cultin^es of hemolytic 

 strains of Staphylococcus aureus are first injected into the skin of 

 guinea pigs and rabbits for a presumptive test. The live cultures 

 capable of producing necrotizing lesions one to txvo days later are 

 selected for the preparation of toxins xvhich are best obtained in 

 eight to fourteen day old broth culture filtrates. Filtrates incapable 

 of producing the primary necrotizing lesions xvere tested by H. 

 Gross for the phenomenon of local skin reactivity. Txventy-five c.c. 

 of the filtrate xvere injected intraciUaneously into rabbits. These 

 injections xvere folloxved by intravenous injections of 2 c.c. of the 

 same filtrate, txventy-four hours later. Sexere hemorrhagic and 

 necrotic lesions appeared at skin sites prepared xvith these filtrates. 



Alechinsky (1936) xvas able to elicit the phenomenon xvith a 

 filtrate of a txventy day old culture of StapJiylococciis aureus iso- 

 lated from X esicles of a case of herpetiform dermatitis of Duhring. 

 The active principles xvere apparently of loxv potency since in 

 order to obtain sexere reactions it xvas necessary to employ a 

 B. coU filtrate either for the preparatory or the proxocatixe injec- 

 tion. The intradermal injection of the staphylococcus filtrate of 

 this author produced no primary necrotic lesions. 



ACTIVE PRINCIPLES OF STREPTOCOCCUS 



In order to facilitate the studies on the mode of preparation of 

 streptococcus active principles, advantage xvas taken of the fact 

 that the skin prepared xvith the factors from one microorganism 



