Macrophage colony-stimulating factor restored chemotherapy-induced granulocyte dysfunctions: role of IL-8 production by monocytes.

We evaluated the influence of M-CSF treatment on granulocyte functions in patients with ovarian cancer. Eighteen patients with ovarian cancer received two consecutive courses of chemotherapy (16 cases, CAP therapy and two cases, CP therapy) at 4-week intervals. M-CSF (8 million U/day) was infused for 7 days starting from the next day after chemotherapy. Superoxide anion production by isolated peripheral blood granulocytes, their phagocytosis, and expression of cell adhesion molecules such as CD11a, CD11b, and CD18 on granulocytes were measured by flow cytometry. Cytokine (IL-8, G-CSF, and GM-CSF) levels in peripheral blood monocyte (PBM) culture supernatants were measured by enzyme-linked immunosorbent assay in 5 out of 18 cases. The levels of CD11a, CD11b and CD18 expression on peripheral blood granulocytes and superoxide anion production by granulocytes were significantly suppressed by chemotherapy without CSF support. The levels of CD11a and CD18 expression on granulocytes were significantly enhanced by administration of M-CSF. When M-CSF was added to cultured PBM, the level of IL-8 in the supernatant increased with the concentration of M-CSF. When IL-8 was added to cultured granulocytes, the levels of CD18 expression on granulocytes and superoxide anion production by granulocytes were significantly increased. These observations suggest that M-CSF enhances the production of IL-8 from monocytes in vivo, thereby improving chemotherapy-induced granulocyte dysfunction.