title: The generation of highly enriched osteoclast-lineage cell populations.
abstract: Osteoclasts form when hematopoietic cells are stimulated by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-kappaB ligand (RANKL) or tumor necrosis factor-alpha (TNFalpha). Osteoclast precursors derive from M-CSF-dependent proliferating hematopoietic cells but cannot yet be purified from mixed populations. M-CSF stimulation of bone marrow cells results in large numbers of nonadherent, proliferating macrophage precursors. These rapidly form adherent bone marrow macrophages (BMM). BMM and their precursors can be isolated free from mesenchymal and lymphocytic cells. BMM precursors derived from CBA-strain mouse bone marrow, when cocultured with ST2 cells (which express RANKL and M-CSF), formed numerous mononuclear osteoclasts, which resorbed bone and expressed tartrate-resistant acid phosphatase (TRAP) and calcitonin receptors (CTR). Addition of approximately 10 BMM precursors to ST2 cultures resulted in over 80% of these cocultures forming functional osteoclasts, suggesting that they are a highly enriched source of osteoclast progenitors. Supporting this, recombinant RANKL/M-CSF-stimulated BMM precursors formed populations in which all cells expressed TRAP. While only a small proportion of these cells (8.6%) expressed CTR, with transforming growth factor-beta (TGFbeta) present RANKL/M-CSF-stimulated BMM precursors formed almost pure (98.4%) CTR-positive osteoclasts after 7 days. This suggests that TGFbeta stimulated the maturation rate of these cells. Passaged or viably frozen BMM precursors gave rise to BMM that also all formed osteoclasts lineage cells after RANKL/M-CSF stimulation. These data suggest that BMM precursors derived from CBA mice are an expanded pool of osteoclast progenitors. These can be employed to generate osteoclast populations of high purity and in large numbers when stimulated by TGFbeta, which greatly augments the osteoclastogenic effects of RANKL.
authors.affiliation: St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia. j.quinn@medicine.unimelb.edu.au
authors.forename: J M W
authors.initials: JM
authors.lastname: Quinn
authors.forename: G A
authors.initials: GA
authors.lastname: Whitty
authors.forename: R J
authors.initials: RJ
authors.lastname: Byrne
authors.forename: M T
authors.initials: MT
authors.lastname: Gillespie
authors.forename: J A
authors.initials: JA
authors.lastname: Hamilton
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology* / Q000187:drug effects; D001862:Bone Resorption / Q000209:etiology / Q000473:pathology; D002352:Carrier Proteins / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D018920:Coculture Techniques; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D010010:Osteoclasts / Q000166:cytology* / Q000187:drug effects; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D011994:Recombinant Proteins / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D011994:Recombinant Proteins; C505687:Tnfrsf11a protein, mouse; C505689:Tnfsf11 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D016173:Macrophage Colony-Stimulating Factor