Tuberculin Reaction and Anaphylaxis. 125 



true anaphylactic skin reaction in all that this term implies. It 

 should be noted, however, that as far as we know no careful analy- 

 sis has ever been made to prove experimentally that such skin 

 reactions run entirely parallel with general anaphylaxis. 



The other type of skin reaction is the typical tuberculin, 

 typhoidin, etc., reaction which begins gradually, within three, 

 four or five hours, reaches its maximum after 24 or 48 hours, and 

 does not fade for four or five days. It is marked by definite 

 inflammatory reactions with perhaps some hemorrhage and a little 

 necrosis. It is distinctly a cell-injury reaction. 



Since this last reaction and general anaphylaxis plainly are 

 shown not to go hand in hand, the question arises, are they of 

 fundamentally different nature or are they perhaps reactions to 

 two different substances in the tuberculin preparations. It has 

 been suggested that the true tuberculin reaction is rather analogous 

 to toxin hypersusceptibility than to true anaphylaxis, and is 

 incited by hypersusceptibility to a toxic constituent of the tuber- 

 culin rather than to the tuberculo-protein. 



Loewenstein and Pick have studied tuberculin chemically and 

 believe that the substance which induces the typical tuberculin 

 reactions belongs to the class of polypeptides and is dialyzable. 



Working with fish bladder membranes we have been able to 

 show, so far, that the substance in O. T. and in the alkalin extracts 

 of ground tubercle bacilli which causes the skin reactions diffuses 

 through such membranes. 



Whether or not this dialyzate produces or fails to produce 

 reaction with the sensitized uterus we have not yet been able 

 conclusively to determine. 



The general trend of our work, however, together with studies 

 to be reported in another place, lead us to make the following 

 preliminary suggestion: 



Substances like whole proteins, cannot establish chemical or 

 physical relationship with the body cells to any degree without the 

 intervention of antibodies, because they are not diffusible. In the 

 case of such substances, therefore, the antibody mechanism is 

 necessary to establish such relationship. 



The instantaneous nature in which the anaphylactic reactions 

 which take place through the intervention of antibodies occur, 

 suggests that these are cell surface phenomena. 



