94 IMMUNITY AND ANAPHYLAXIS 



intestinal digestion is incapable of splitting, that is to say, 

 of transforming into amino-acids and which may pass into 

 the interior of the organism as colloids will provoke the 

 formation of antibodies and in consequence the anaphylactic 

 state. These are the causes of the habitual or accidental 

 anaphylactic intolerance for certain foods, as well as for 

 infections by mouth, individual or specific, in typhoid, 

 cholera, tuberculosis, etc. 



The organism can nourish itself on foreign albumins only 

 in cases it can assimilate them, that is to say, can transform 

 them into albumins of its own species; and we know that 

 to do this it can absorb them only in the completely dis- 

 integrated state of the amino-acid. This disintegration is 

 the role of gastro-intestinal digestion. What then becomes 

 of the incompletely digested albumins which have penetrated 

 into the interior of the organism in the colloidal state? 

 They can neither be assimilated nor eliminated in the 

 colloidal state. 



Two hypotheses are possible: Either they would accu- 

 mulate in some part to which would be brought every other 

 unassimilable foreign body where they would be surrounded 

 by leukocytes; or else the interior of the organism would 

 finish the incomplete gastro-intestinal digestion and would 

 render them assimilable or eliminable as amino-acids. It 

 is this last hypothesis which happens in all the known cases. 

 It is true that up to the present we have never been able to 

 prove this parenteral digestion, but if we have no direct 

 experimental proof of it, we know with certainty by numer- 

 ous experiments (Hamburger and Moro and others) that 

 when we inject a rabbit with horse serum, we can recover 

 this serum in the rabbit's blood some time after the injection 

 but that finally this serum will disappear at a given moment 

 and that this disappearance, often quite sudden, will always 

 coincide with the appearance in the rabbit's blood of specific 

 antibodies. From the point of view of the reaction which 

 follows, it is of little importance by what route (intestinal, 

 subcutaneous, intravenous) the colloidal antigen penetrates 

 into the organism. 



The transformation in the organism of a colloid into a 



