ACTIVATION OF HUMAN-MONOCYTES FOR NITROBLUE TETRAZOLIUM REDUCTION AND THE SUPPRESSION OF LYMPHOCYTE-RESPONSE TO MITOGENS

  • 1 January 1980
    • journal article
    • research article
    • Vol. 41  (2) , 309-316
Abstract
Human peripheral blood mononuclear cells freed from polymorphis reduce nitroblue tetrazolium (NBT). This reduction is due to monocytes, i.e., adherent, phagocytic, esterase-positive cells with Fc receptors. Monocytes allowed to phagocytose zymosan show increased NBT reduction which under optimal conditions is 12.2 .+-. 2.4 .times. 10-9 mol .cntdot. h-1 .cntdot. 10-6 monocytes. Monocytes which have phagocytosed zymosan depress the mitogen response of human lymphocytes to PHA [phytohemagglutinin]. This effect of activated monocytes is due to a soluble inhibitory mediator which appears in the supernatant after culture for 24 h. Its appearance requires protein synthesis. NBT reduction of peripheral blood mononculear cells may be used as a test for the state of monocyte activation in disease. The possibility that activated monocytes may depress blast transformation in vitro in disease states is discussed.