THE SPLIT PRODUCTS OF TUBERCLE BACILLUS 175 



protein. (3) The injection of non-fatal doses of the poison 

 renders animals at least temporarily refractory to subsequent 

 injections of what would normally be fatal doses. We 

 have always held that this is due to the establishment of a 

 tolerance. This is important and we will refer to it again 

 when we discuss the action of tuberculin. (4) The poison 

 is not absorbed in vitro by brain, lung, or liver tissue. " These 

 experiments seem to emphasize the absence of any possible 

 identity of this protein fragment with the true toxins. 

 The results, however, are in accord with the symptoms 

 produced by the cell poison. Recovery from a sub-lethal 

 dose is rapid and complete, and this would imply that the 

 contact between the body cells and the poison is transi- 

 tory, and non-destructive. It appears to be more like a 

 fulminating irritation, and may result in an arrest of func- 

 tion due to a disturbance in the physical equilibrium of the 

 cells affected." (5) The serum of normal guinea-pigs 

 incubated with the poison does not materially, at least, 

 decrease its action. (6) The poison does not induce any 

 local reaction when introduced intradermically in guinea- 

 pigs sensitized to tuberculoprotein. Four animals sensitized 

 nineteen days previously with the cell residue, and which 

 had been found to be sensitive to an extract emulsion of 

 tubercle bacilli, and four animals rendered and proved 

 sensitive by a watery extract of tubercle bacilli received 

 intradermal injections of the poison, and under close obser- 

 vation showed no reaction. This is as should be expected. 

 The skin reaction, like other tuberculin reactions, results 

 from the cleavage of the tuberculoprotein. The cleavage 

 products produce no such reactions. (7) Auer and Lewis 1 

 showed that prophylactic treatments w r ith atropine save 

 a large percentage of animals from death by anaphylactic 

 shock on the reinjection of the* homologous protein. We 

 claim that our protein poison is the active agent in 

 anaphylaxis. Now, White and Avery show that atropine 

 protects 75 per cent, of guinea-pigs from death after the 



1 Amer. Jour. Physiology, 1910, xxvi, 439. 



