The Relation Of The Opsonic Index To The Leucopenia And Leucocytosis Following Injections Of Heated Bacterial Cultures

Abstract

In the course of a series of experiments on rabbits on the effect of injections of killed bacteria on the leucocytes of the circulating blood, it was found, as pointed out by others, that an initial leucopenia was produced which was followed by a marked leucocytosis. It occurred to us that possibly some relation existed between the leucopenia and the negative phase, and the leucocytosis and the positive phase, of the opsonic index. If such a relation should prove constant, it might be of some practical as well as theoretical significance. There seemed to be a slight possibility of substituting simple leucocyte counts for the cumbersome opsonic technique as a means of determining the reaction of the individual to the injection of dead bacteria, and with this idea in mind our animal experiments were continued. Metchnikoff1 and his pupils found that intraperitoneal and intravenous injections of a culture of cholera vibrios were followed by an immediate diminution in the number of the leucocytes. Howard2 showed: (i) that intraperitoneal injections of cold salt solution into guinea-pigs caused a slight leucocytosis in four or five hours; (2) that intraperitoneal and subcutaneous injections of typhoid toxins and intraocular injections of killed typhoid bacilli produced a very rapidly developing and marked primary hypoleucocytosis which was followed by a marked hyperleucocytosis. Staubli3 made intraperitoneal injections of typhoid toxin and noted a primary hypoleucocytosis followed by a considerable hyperleucocytosis. Dean4 found that after injection of diphtheria toxin ?Received for publication November 15, 1908. t Read by title before the American Association of Pathologists and Bacteriologists, Ann Arbor, Mich., April 18, 1908.