The separation of the phagocytic cells of the peritoneal exudate into two distinct types.

Abstract

The observations reported in the preceding communication 1 led us to consider the possibility that the phagocytic cells occurring in peritoneal exudates might be separated into the same two groups that were found in the spleen. It has been possible to demonstrate that this is true. A normal rabbit was given intraperitoneally 25 cc. of whole blood, which had been removed by a sterile puncture from the heart of another rabbit, and, after 24 hours, samples of the exudate were removed and studied. Another injection was then given and the examination repeated at the end of the second 24 hours. This procedure was repeated at 24 hour intervals over as long a time as was desired. Some of the experiments were carried out on rabbits whose blood-cells had been carefully matched, while in other instances animals were selected in which the serum of one agglutinated the red blood-cells of the other and vice versa. The exudate was studied with neutral red and Janus green in vital-dye films. It has been shown 2 that the first reaction that takes place after the introduction of any substance into the peritoneal cavity is the emigration of polymorphonuclear leucocytes, which appear in the exudate at the end of four to six hours. In the material obtained from our animals at the end of 24 hours there were always large numbers of leucocytes, the majority of which were actively motile, though some were rounded up and a few were in the “non-motile phase.” In addition to these, the predominant cell was the typical clasmatocyte which had phagocytized erythrocytes and whose general appearance corresponded very closely with those previously described. 1 They were usually large cells, varying in size from 20 to 30 micra in diameter.