(S2 LOCAI, TISSUE REACTIVITY 



ol ilic inatc'iial which iciuains alter the second acid s()liil)le IVac- 

 tions ha\e heen renioxed. It is also identical with (he whole 

 j)rotein. 



Reducing substance is j)iesent in A, B and in the residue but 

 it is minute in the residue Traction in proporticjn to the amount. 

 A- and B-fractions have prc)portic:»nately lar^e amounts of reduc- 

 ing substance. They possibly correspond to the outer parts of the 

 vibrio. A-fraction approaches the ^vhole xibrio in its serological 

 activity. B- and residue fractions are less active as antigens and in 

 immunological reactions in the test tube. If a strain is smooth, it 

 contains more reducing sufjstance than B. If reducing substance 

 is greater in B than A, the strain is rough-smooth. 



Hydrolized specific polysaccharide of the vibrio is considered 

 by Linton, Singh and Seal as source of the reducing substance in 

 cjuestion. 



These authors prepared rabbits by three simiUtaneous injec- 

 tions of the various fractions described above. The "agar wash- 

 ings" cultine filtrates containing the active principles were used 

 for the intravenous provocative injection (i.e., 0.35 c.c.) . In their 

 experiments A-fraction yielded ccjnstant and typical reactions. 

 Whole killed culture, B- and residue fractions were totally devoid 

 of the skin-preparatory effect. The work is of special interest be- 

 cause it indicates the possibility of obtaining the active principles 

 in fraction A, which constitiUes an important part of the cholera 

 vibrio in its inmumological relationships. The identity of the 

 active principles, of course, still remains iniknown, although the 

 wcjrk offers interesting information consistent \vith obserx ations on 

 their innmniological behaxior. 



CHEMICAL STUDIES ON ACTIVE PRINCIPLES OF B. PF.STIS 



After rejjroducing the j:)henomenon with B. pestis ciiltines, as 

 described in Clhapter n, ]ouk<)\v-\V^erejnikow and Lij^atova 

 (ic)'}'^-'^) attenijited chemical studies on the active principles. 

 The following materials were tested for their ability to elicit the 

 phenomenon: 



Nucleoprotein of B. pestis: 



The material \vas j)re}3ared according to the techniciue de- 

 scribed by Lustig and (ialeotti, i.e., cultures \\'ere slightly alka- 

 lini/ed with 0.75 to 1 per cent of NaOH and then j)recipitated 

 with acetic acid. 



