[The effect of the bone marrow fibroblasts from patients with malignant diseases of the blood system on the colony-forming capacity of granulomonocytic precursor cells].

The inhibiting activity of bone marrow fibroblasts and their ability to sustain survival of granulocytic cell precursors have been studied in patients with chronic myelocytic leukemia, chronic lymphoproliferative disorders, acute leukemia, myelodysplastic syndrome. Fibroblast conditioned medium inhibits proliferation of granulomonocytic precursors stimulated by leucocyte feeder layer or leucocyte conditioned medium. The effect depends both on the presence of monocytes and the specificity of the disease. The inhibitory effect is related with long-ranged factors. Bone marrow fibroblasts are able to sustain survival of hemopoietic precursors via humoral and cell-cell mechanisms. The regulatory role of bone marrow fibroblasts in hemopoietic disorders is discussed.