“The enzymes of inflammatory exudates. A study of the enzymes concerned in inflammation and their relation to various types of phagocytic cells”

Abstract

The leucocytes of an inflammatory exudate produced by injecting aleuronat into the pleural cavities of dogs digest protein both in an alkaline and in an acid medium (uncoagulable protein nitrogen being estimated by the Kjeldahl method). The following evidence shows that two enzymes are present:

(a) Cells, dried after treatment with absolute alcohol and ether and then reduced to a powder, digest actively in an alkaline medium (0.2 per cent. sodium carbonate), but have almost completely lost the power of digesting in an acid medium (0.2 per cent. acetic acid).

(b) By subjecting washed cells of a sterile inflammatory exudate to varying degrees of heat, their power to digest in an alkaline and in an acid medium is lost at a temperature above 70° C. At temperatures between 55° and 65° C. the power to digest in an alkaline medium is unimpaired but in an acid medium it is much diminished.

(c) With cells of exudate removed from the pleural cavity twenty-four hours after the injection of aleuronat, digestion is very active in an alkaline medium, but less active in an acid medium. At the end of from three to five days, power of digesting in an alkaline medium is diminished or unchanged, but the acid digesting power is increased.

At the end of twenty-four hours after injection of aleuronat polynuclear leucocytes with fine granulation are predominant and from 85 to go per cent of the cells are present. The cells, according to observations previously reported, contain a ferment with acts in an alkaline medium. At a later stage of inflammation when large mononuclear phagocytic cells are predominant, the power of digesting in an acid medium is increased and bears a relation to the proportion of mononuclear phagocytes. If washed red blood corpuscles of the rabbit are injected into the pleural cavity of the dog, at the end of twenty-four hours an exudate is produced very rich in large mononuclear cells, and, in correspondence, the power of the cells to digest in an acid medium is greater than that of the twenty-four hour aleuronat exudate.