“Enzymes and anti-enzymes of inflammatory exudates”

Exudates obtained by injecting suspensions of aleuronat into the pleural cavities of dogs and rabbits were subjected to autolysis. The Kjeldahl method was used to determine the nitrogen of coag-ulable proteins converted by digestion into soluble form.

Inflammatory exudates removed one or two days after injection of the irritant undergo very little change, while those removed three or four days after the onset of inflammation exhibit appreciable though slight autolysis. There is no relation between the amount of digestion and the number of cells which are present. If the cells are separated by centrifugalization from the serum and suspended in normal salt solution, well-marked autolysis is demonstrable. By recombining cells and serum it can be shown that the serum inhibits this autolysis. When this inhibitory action is prevented by heating serum to 100° C., leukocytes acting upon the coagulated serum cause very active digestion. In the following experiments nitrogen of uncoagulable substances is represented by cubic centimeters of sulfuric acid:

The anti-enzyrnotic action of the serum is unaffected by a temperature of 65 ° C., but is prevented at 75 ° C. The proteolytic ferments of the leukocytes act both in an acid and in an alkaline medium, but are most efficient in the latter. The anti-enzymotic action of the serum is favored by an alkaline reaction, but is completely prevented in an acid medium, The serum of the exudate contains a proteolytic ferment, which is active only in an acid medium.