TUBERCULOSIS 57 



Experience shows clearly that the production of antibody 

 far exceeds the production of tuberculin. Besredka deter- 

 mined that in the blood of guinea-pigs, antituberculin in 

 excess appeared four days after the infecting injection and 

 before any pathologic manifestation, either local or general. 

 In consequence there is in the evolution of a tuberculous 

 focus a period during which all the tuberculin secreted by the 

 bacteria will be fixed in the focus or the surrounding tissue. 

 During this period the excess production of antituberculin 

 will be forcibly stopped, the quantity of it which circulates 

 in the blood will progressively diminish and at the same 

 time, thanks to the intervention of leukocytes, the tuber- 

 culous focus can be isolated from the remainder of the 

 organism without forming a sequestrum. The lesion may 

 definitely heal by a mechanism which we will examine later 

 leaving a scar, or a focus can remain in a latent condition 

 for a longer or shorter time and can be revivified by the onset 

 of another disease or sometimes even by a simple traumatism. 

 The excess production of antibody in the cells thus becomes 

 the cause of the lesion and of a possible cure. 



SUMMARY. There results from the total of studies on 

 the properties of tuberculin and antituberculin as well as on 

 the reciprocal reactions of these substances on the organism : 



First. That all tuberculins, regardless of their method of 

 preparation and origin (in artificial broth cultures or infectious 

 foci), act by the same principle of pathogenicity, and that the 

 observed difference of action results only from their concentra- 

 tion and from the medium in which they are placed. The 

 biologic differences which are observed may be of the same 

 sort as those, for example, which are found in wines of differ- 

 ent ages in which the alcohol, always the same, but in greater 

 or less quantity may be associated with all sorts of substances 

 which modify its action in a very definite way. We may 

 assume with the certainty that the virulence of all germs 

 depends only on the quantity of the pathogenic sub- 

 stance secreted which passes to the free state in the external 

 medium. 



Second. That antituberculin which multiplies in the cells 

 by the action of tuberculin remains attached in the cells probably 



