title: Bone marrow stromal cells spontaneously produce Flt3-ligand: influence of ionizing radiations and cytokine stimulation.
abstract: OBJECTIVE
  To define the ability of human bone marrow (BM) stromal cells to produce fms-like tyrosine kinase 3 (Flt3)-ligand (FL), and the effect of irradiation, tumour necrosis factor-alpha (TNFalpha) or tumour growth factor beta (TGFbeta) on FL production.
  
  
  METHODS
  Primary BM stromal cell cultures were irradiated at 2-10 Gy or were stimulated with TNFalpha or TGFbeta1. The presence of FL was tested in culture supernatants and in cell lysate. The presence of a membrane-bound form of FL and the level of gene expression were also tested.
  
  
  RESULTS
  Primary BM stromal cells spontaneously released FL. This production was increased by TNFalpha but not by TGFbeta1 or by irradiation. Chemical induction of osteoblastic differentiation from BM stromal cells also induced an increase in FL release.
  
  
  CONCLUSIONS
  Our results suggest that the observed increase in FL concentration after in vivo irradiation is an indirect effect. The possible implication of BM stromal cells in these mechanisms is discussed.
authors.affiliation: Laboratoire de radiotoxicologie experimentale, DRPH-SRBE, IRSN, Fontenay aux roses, France. jean-marc.bertho@irsn.fr
authors.forename: Jean Marc
authors.initials: JM
authors.lastname: Bertho
authors.forename: Christelle
authors.initials: C
authors.lastname: Demarquay
authors.forename: Moubarak
authors.initials: M
authors.lastname: Mouiseddine
authors.forename: Noémie
authors.initials: N
authors.lastname: Douenat
authors.forename: Johanna
authors.initials: J
authors.lastname: Stefani
authors.forename: Marie
authors.initials: M
authors.lastname: Prat
authors.forename: François
authors.initials: F
authors.lastname: Paquet
mesh_terms: D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism* / Q000528:radiation effects; D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D008565:Membrane Proteins / Q000096:biosynthesis*; D010006:Osteoblasts / Q000166:cytology; D010641:Phenotype; D017154:Stromal Cells / Q000378:metabolism / Q000528:radiation effects; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D008565:Membrane Proteins; D053773:Transforming Growth Factor beta1; D014409:Tumor Necrosis Factor-alpha; C084881:flt3 ligand protein