Leucocyte Agglutinating Systems

¹ From the Department of Anatomy, Temple University School of Medicine, Philadelphia, Pennsylvania

An alteration of leucocyte adhesiveness, as evidenced by agglutination, endothelial sticking, or leucopenia, is associated with a variety of phenomena such as local tissue injury, bacteremia, hypersensitivity reactions, Shwartzman phenomenon and certain types of agranulocytosis. Because such changes in leucocyte dispersion may reflect basic mechanisms fundamental to these phenomena, leucocyte agglutinating systems were studied by a technique for quantitating leucocyte agglutination in vitro. The techniques for inducing leucocyte agglutination involved the nonspecific agglutination resulting when blood is incubated, inflammation and the exposure of the cells to foreign protein in both a sensitive and nonsensitive system. The nonspecific agglutination and the agglutination from inflammation are inhibited by hydrocortisone. That resulting from foreign protein is not. Heparin at high concentrations inhibits the agglutination induced by each of the experimental leucocyte agglutinating stimuli studied. It is postulated that there are at least two leucocyte agglutinating systems as defined by their sensitivity to hydrocortisone and that both systems act through a final common pathway which is inhibited by heparin.