(S6 LOCAL TLSSUE REACTIVITY 



B. l\jj/i()Mi.y (ioinjxn isoii ol the dry weights ol the sanic Iractions 

 with those ol the corresponding washings showed a chHerent pro- 

 jjortion between the C- and P-fractions. The predominant frac- 

 tion in groiuid material was the acetic acid precipitate whilst in 

 washings the C-Fraction predominated. Attempts to fractionate 

 cidture filtrates in synthetic medinm proved troublesome and of- 

 fered no advantage because of the strong primary skin reactions 

 produced by these filtrates and also the fact that their skin-pre- 

 paratory potency was ^veaker than in ordinary "agar washings." 



Apitz reached the conclusion that the active principles of the 

 phenomenon are contained in two different fractions of the bac- 

 terial substances, i.e., nucleoprotein and carbohydrate fractions. 

 On accoimt of the complex character of the nucleoprotein frac- 

 tion, ftnther work was considered necessary by this author in or- 

 der to study the relation of the active principles to the species 

 specific antigens. Although active principles of high activity coidd 

 be obtained in the C-fraction, this author did not believe that 

 they were identical with the type specific carbohydrates, since in 

 contrast to the latter they ^vere extremely luistable and destroyed 

 by prolonged heating. Ho\vever, in his opinion the |)ossibility ^vas 

 not excluded that they represented a more labile sid)stance from 

 which the type specific carbohydrates are derived. It is significant 

 that the amoimt of nucleoprotein fraction increases in ctdtines 

 tmdergoing autolytic changes whilst the C-fraction is mostly ob- 

 tained in yoinig actively growing bacterial cidtmes ^vith little 

 autolysis. Apitz also suggested that his resiUts indicating a doid)le 

 soince (jf the active principles, namely, from nucleoproteins de- 

 rived from l)acterial bodies and from the C-fraction derived from 

 the metabolic activity of live bacteria, may explain some of the dis- 

 crepancies in the 1 iterating concerning the origin of the active 

 principles. 



As will be seen from the sidjsequent chapters, investigations 

 demonstrating antigenicity of active principles of the phenome- 

 non, suggest that they are either protein in nattne or perhaps 

 associated with proteins. The investigations of Apitz seemed in- 

 consistent with this point of view since he reported the isolation 

 of a biuret-negative fraction which ^vas slowly dialyzed through 

 "Cellophane." This necessitated the repetition of the Avork of 

 Apitz (Shwartzman, Morell, and Sobotka (19-^7) in Avhich his 

 procedine ^vas carried out with several batches of B. typhosus 

 "agar ^vashings" filtrates. 



