SIGNIFICANCE AND ORIGIN OF (DEFENSIVE) FERMENTS S/ 



fuel on the one hand, and certain constructive 

 units on the other. 



Many observations point to the fact that parenter- 

 ally introduced substances, in so far as they can be 

 modified, are utilized by the organism ; that is, they 

 serve as nourishment. The digestion, which would 

 otherwise take place in the intestine and prevent the 

 passage of disharmonious material into the body, is 

 performed by the blood. 



It is an open question from what source these fer- 

 ments, which we are going to call defensive ferments,, 

 take their origin. Many facts accord with the sugges- 

 tion that the leucocytes play a part in this connection 

 (see also Lit. 23). They probably give off these 

 ferments to the circulation. If so, we should then 

 have in the blood plasma phenomena more or 

 less analogous to those observed, for instance, by 

 B. Friedrich Miiller, during the dissolution of the 

 fibrin that is excreted into the alveoli in cases of pneu- 

 monia. We see here numerous leucocytes penetrating 

 into the solid exudate and dissolving it, after which an 

 absorption of the products of decomposition begins, 

 a kind of digestion taking place in the interior of 

 the alveoli. Here also, as can be shown by special 

 experiments, ferments can be demonstrated in the 

 contents of the alveoli (in the expectorated sputum) * 

 and these ferments take their origin from the leuco- 

 cytes. The old view, whereby the leucocytes take up 



