Establishment and characterization of a novel human bone marrow stromal cell line, FS-1

We have established a human stromal cell line derived from the bone marrow of a patient with chronic myelogenous leukemia in blast crisis. This cell line, designated FS-1, exhibits a fibroblastoid morphology and does not express any hematopoietic cell marker tested. FS-1 is negative for alpha-naphthyl acetate esterase, acetylated LDL, von Willebrand factor, and shows no phagocytosis. This cell line is positive for acid phosphatase, alkaline phosphatase, collagen types I, III, IV, and fibronectin. cDNA from FS-1 cells was subjected to amplification by the polymerase chain reaction to assess the constitutive expression of several cytokine genes. Transcripts for interleukin (IL)-6, IL-7, macrophage colony-stimulating factor (M-CSF), and stem cell factor (SCF) were detected in FS-1 cells. IL-6 and SCF also were detected in the culture supernatants of FS-1 at a concentration of 95 pg/ml and 21.2 pg/ml, respectively. These data show that FS-1, established from a human bone marrow, is a stromal cell line which was not generated using transfection with SV40 T antigen. FS-1 cells may be useful in supporting human hematopoietic cells for experimental manipulation.