INHIBITION INVIVO OF MOUSE GRANULOPOIESIS BY CELL-FREE ACTIVITY DERIVED FROM HUMAN POLYMORPHONUCLEAR NEUTROPHILS

  • 1 January 1978
    • journal article
    • research article
    • Vol. 51  (5) , 889-901
Abstract
Cell-free extracts from human polymorphonuclear neutrophils (PMN) inhibited rebound granulopoiesis in the bone marrow and spleen of mice pretreated with cyclophosphamide to remove endogenous PMN. Absolute numbers of granulocyte-monocyte progenitor cells (CFU-C) and net endogenous colony-stimulating activity (CSA) production were increased 3 days after cyclophosphamide in the bone marrow and 6 days after in the spleen. Administration of PMN extract to the drug-treated mice prior to rebound granulopoiesis substantially decreased CSA production and CFU-C but not spleen B [bone marrow-derived] lymphocyte colony-forming cells. Mice treated with PMN extract had decreased levels of CSA in serum and in conditioned medium of marrow-free bone, heart and lung cultures. Inhibition was reversed by injection of bacterial [Salmonella typhosa] lipopolysaccharide. Extracts from PMN of patients with chronic myelogenous leukemia, inactive in vitro, had no effect in vivo. Inhibitory activity derived from PMN can control granulopoiesis in vivo.