title: Effect of stem cell factor (c-kit ligand), granulocyte-macrophage colony stimulating factor and interleukin 3 on hematopoietic progenitors in human long-term bone marrow cultures.
abstract: In this paper we attempt to improve upon the methods of hematopoietic stem cell expansion. We evaluate the effects of recombinant human stem cell factor (SCF or c-kit ligand) alone and also in combination with recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin 3 (IL-3), on cell proliferation and differentiation in human long term bone marrow cultures (LTBMC). Weekly addition of 5 ng/ml of SCF with 25% serum containing media resulted in increased recovery of total nonadherent cells, granulocyte-macrophage colony forming units (CFU-GM), and burst-forming units erythroid (BFU-E) at week 1, but the number of bone marrow (BM) progenitor cells fell below the level of untreated control cultures at weeks 3 (BFU-E) and 4 (CFU-GM). At week 8, when the cultures were terminated, the CFU-GM recovery was markedly reduced in flasks supplemented with SCF compared with the controls (p < 0.002). Moreover, SCF treatment induced the early disappearance of BFU-E. When LTBMC were supplemented with the combination of SCF plus GM-CSF (100 U/ml) and IL-3 (5 ng/ml), synergistic activity of the CSFs was observed at week 1. The number of BM colony forming cells (CFC) rapidly declined below the level of growth factor-free controls, leading to the early exhaustion of the culture when SCF was combined with GM-CSF. By comparison, GM-CSF and IL-3 alone induced a statistically significant increase above the controls (no growth factor) in the number of nonadherent cell colonies of CFU-GM and BFU-E. Analysis of adherent layer cells from cultures supplemented with SCF showed increased cellularity, no adipogenesis, and early disappearance of myeloid progenitors while the percentage of CFU-GM in S phase, assessed by cytosine arabinoside (Ara-C) suicide assay, was 9.2 +/- 5% SD versus 27.7 +/- 10% SD in control (no growth factor) samples (p < 0.01). SCF increased the number of fibroblast colony forming units (CFU-F) and also showed a synergistic activity (9.6-fold increase) when combined with IL-3. These findings suggest that SCF, GM-CSF and IL-3 exert their activity on different cell populations within the hematopoietic system. Further investigations are needed to optimize the use of SCF in supporting hematopoiesis.
authors.affiliation: Autologous Bone Marrow Transplant Team, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
authors.forename: R M
authors.initials: RM
authors.lastname: Lemoli
authors.forename: S C
authors.initials: SC
authors.lastname: Gulati
mesh_terms: D001853:Bone Marrow / Q000187:drug effects; D001854:Bone Marrow Cells; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D016298:Hematopoietic Cell Growth Factors / Q000494:pharmacology*; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D006801:Humans; D007377:Interleukin-3 / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000494:pharmacology; D019089:Stem Cell Factor
chemical_list: D016298:Hematopoietic Cell Growth Factors; D007377:Interleukin-3; D011994:Recombinant Proteins; D019089:Stem Cell Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor