THE PRODUCTION OF GRANULOCYTE-COLONY-STIMULATING FACTOR AND INTERLEUKIN-6 BY HUMAN BONE-MARROW STROMAL CELLS IN APLASTIC-ANEMIA

Stromal cells are known to produce granulocyte colony-stimulating fact or (G-CSF) and interleukin 6 (IL-6). To assess the function of bone ma rrow stromal cells in the pathological state, we studied their in vitr o ability to produce G-CSF and IL-6 in 9 patients with aplastic anemia and 5 normal volunteers, using an enzyme immunoassay method. Constitu tive production of IL-6, but not G-CSF, was detected in almost all cas es. Interestingly, the inducible production of G-CSF and IL-6 by strom al cells after stimulation with interleukin-1 and/or lipopolysaccharid es was severely depressed in 3 patients with aplastic anemia. Our resu lts may reflect poor hematopoietic activity in the bone marrow in some cases of aplastic anemia.