172 TOXINES AND ANTITOXINES. 



RUPPEL and KiTisniMA 1 made a further investigation of 

 tuberculinic acid. It was from three and a half to four times as 

 poisonous as dry old tuberculine. It was much more poisonous 

 on intercerebral injection, especially in the case of tuberculous 

 guinea-pigs (1 grm. killed 40,000 kilos.). Other nucleic acids 

 were less poisonous. Tuberculinic acid prepared by the older 

 somewhat drastic method of KOSSEL was found to be five times 

 less poisonous than the new preparation. RUPPEL and KITI- 

 SHIMA then prepared from tuberculinic acid by Kossel's method, 

 a substance similar to thymic acid, tuberculothymic acid, " 1 c.c. 

 of which contained as much poison specific for tuberculous 

 individuals as 20 c.c. of Koch's tuberculine" (BEHRING), and 

 also a still more simple poisonous substance of as yet unknown 

 nature, tuberculosine, 1 grm. of which was equivalent to 25 to 

 30 c.c. of Koch's tuberculine. 



According to BEHRING this represents the poison-nucleus, 

 around which the other substances are grouped in some way or 

 other, and without which there can exist no poison with the 

 specific action of tuberculine. 



Important as these researches are with respect to the toxic 

 action of the tubercle bacilli, they have yet little claim upon our 

 attention here, since there can be no question of these substances 

 obtained by drastic chemical methods being true toxinvs. 



A further objection to drawing comparisons between these 

 poisons and diphtheria poison is that the former are relatively 

 only slightly poisonous at all events to the healthy organism. 



There is never any formation ofantitoxine in the case of these 

 poisons. 



Tuberculine is invariably but slightly poisonous to a healthy 

 organism, and its toxic action can be still further reduced 

 by processes of purification without injuring its specific 

 activity. 



On the other hand, it has frequently been shown by RoMER, 2 

 BucHNER, 3 and others that the action of tuberculine, as regards 

 its toxic effects, is non-specific. The same pyrogenic and local 

 inflammatory symptoms could also be produced, in the same 

 degree, by the proteins of other micro-organisms (pyocyaneus, 



^Behring, Die Diphtherie, Berlin, 1901, 91 ; see also Behring, " Ueber 

 die spez. giftigen Eigensch. d. Tuberkulinsaure," Berl. Uin. Woch., 1899, 

 537. 



2 Romer, " Ueb. d. formativen Reiz d. Proteine Buchners," Berl. klin. 

 Woch., 1891,886; " Tuberkulinreaktion d. Bazillenextrakte," Wien. klin. 

 Woch., 1891, 835. 



3 Buchner, " Tuberkulinreakt. d. Proteine nicht spezif. Bakt.," Munch, 

 med. Woch., 1891, 841. 



