Granulocytes as effectors in cell-mediated cytotoxicity of adherent target cells

In the microassay for cell-mediated immunity, detachment of adherent target cells from the wells occurs to an even greater extent when tested with granulocytes than when tested with lymphocytes. Intact cells are not necessary since the sonic extract from granulocytes causes the same effect. The reaction by granulocytes appears to be mediated by enzymes, and is inhibited by the presence in the wells of hyaluronic acid. Moreover, it is limited to the detachment of adherent target cells, since neither intact nor sonically disrupted granulocytes exhibit cytotoxic activity in the chromium release assay. The detachment of target cells is also inhibited by heparin which may be used to specifically mullify the effect of granulocytes contaminating lymphocyte suspensions.