EFFECT OF GLUCAN ON GRANULOPOIESIS AND MACROPHAGE GENESIS IN MICE

Abstract

Glucan, a potent reticuloendothelial stimulant, is a glucopyranose polysaccharide derived from zymosan. [The immunopharmacology of macrophage activators is of interest because of their potential role in cancer therapy.] knowing glucan''s potential as an immunotherapeutic agent, studies were performed in order to determine its effect on granulopoiesis and macrophage production in mice. One week after the i.p. injection of 4 mg of glucan, there was a 10-fold increase in colony-forming cells in the spleen and .apprx. a 2-fold increment of cells in the bone marrow and the peritoneal cavity capable of colony formation in vitro. There was a relative and absolute increase in the number of pure macrophage colonies from bone marrow and spleen. The total macrophage content in spleen, peritoneal cavity and bone marrow was also increased in the treated mice. Serum from glucan-injected mice had high colony-stimulating activity levels and the peritoneal macrophages elaborated increased colony-stimulating activity in vitro as compared to controls. Peripheral white blood cell counts were 2 times greater than those of control in the glucan-treated mice. Glucan administration seems to result in increased granulocyte and macrophage production. The enhanced leukopoiesis is probably mediated in part by augmented release of colony-stimulating activity from macrophages. These observations suggest that the use of glucan as an immunotherapeutic agent can result in an increased number of available effector cells.