title: Clonal endothelial cells produce humoral factors that inhibit osteoclast-like cell formation in vitro.
abstract: Angiogenesis and bone remodeling are closely associated, and vascular endothelial cells may have potential roles for osteoclastic bone resorption. We examined whether clonal endothelial cells established from bone, aorta and brain of Balb/c mice influenced osteoclast-like cell formation in vitro. As low as 1% conditioned media of those endothelial cells inhibited osteoclast-like cell formation in bone marrow cultures induced by 1,25-dihydroxyvitamin D3, and did so in spleen cell cultures in the presence of soluble receptor activator of nuclear factor-kappaB ligand (RANKL), M-CSF and prostaglandin E2. The level of osteoprotegerin (OPG), a decoy receptor for RANKL, secreted by endothelial cells was not high enough to inhibit osteoclastogenesis. These observations suggest that endothelial cells derived from various tissues secrete factor(s) that inhibits precursors to differentiate into osteoclasts even in the presence of optimal stimulators for osteoclastogenesis. Hence, endothelial cells in bone may inhibit recruitment of fresh osteoclasts, and those in tissues other than bone may be involved in prohibiting ectopic osteoclastogenesis.
authors.affiliation: Department of Medicine, University of Tokyo School of Medicine, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Chikatsu
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Takeuchi
authors.forename: Seiji
authors.initials: S
authors.lastname: Fukumoto
authors.forename: Kazuki
authors.initials: K
authors.lastname: Yano
authors.forename: Naoya
authors.initials: N
authors.lastname: Fujita
authors.forename: Takashi
authors.initials: T
authors.lastname: Tsuruo
authors.forename: Toshiro
authors.initials: T
authors.lastname: Fujita
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology / Q000378:metabolism*; D001842:Bone and Bones / Q000166:cytology / Q000378:metabolism*; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D002352:Carrier Proteins / Q000494:pharmacology; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D002999:Clone Cells; D004727:Endothelium / Q000166:cytology / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D008297:Male; D008562:Membrane Glycoproteins / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D010010:Osteoclasts / Q000166:cytology*; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D013234:Stem Cells / Q000166:cytology
chemical_list: D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; C505687:Tnfrsf11a protein, mouse; C505689:Tnfsf11 protein, mouse