title: Peripheral blood mononuclear cells develop into multinucleated osteoclasts in tissue culture.
abstract: BACKGROUND
  Previous studies have shown that osteoclasts are derived from mononuclear cells of hemopoietic bone marrow and peripheral blood. The purpose of this study was to demonstrate the presence of multinucleated osteoclasts after adding mononuclear cells from peripheral blood into established explants of fetal mouse calvaria in vitro.
  
  
  METHODS
  In order to utilize osteoclast-free bone, the fetal calvariae were obtained from 13-14-day pregnant Swiss Webster mice and cultured in BGJb medium for 9 days. At day 9, peripheral blood mononuclear cells were isolated as a light density layer from adult Swiss Webster mice with the Ficoll-Paque density gradient separation method and co-cultured with the osteoclast-free, fetal mouse calvaria.
  
  
  RESULTS
  After 10 days of co-culture, multinucleated cells, which have all the characteristics of osteoclasts, were found in juxtaposition to seams of woven bone. Two multinucleated osteoclasts per one million light density peripheral blood mononuclear cells were found in the experimental group; none were found in the mononuclear cell-free control group.
  
  
  CONCLUSIONS
  Peripheral blood mononuclear cells can give rise to multinucleated osteoclasts in developing bone in vitro but will not develop without bone.
authors.affiliation: Department of Neurobiology, University of California, Los Angeles, USA.
authors.forename: C
authors.initials: C
authors.lastname: Shih
authors.forename: G W
authors.initials: GW
authors.lastname: Bernard
mesh_terms: D000818:Animals; D001862:Bone Resorption; D001842:Bone and Bones / Q000166:cytology; D002454:Cell Differentiation; D002478:Cells, Cultured; D018920:Coculture Techniques; D003593:Cytoplasm / Q000648:ultrastructure; D017886:Durapatite / Q000032:analysis; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D006412:Hematopoietic Stem Cells / Q000166:cytology; D007963:Leukocytes, Mononuclear / Q000166:cytology*; D051379:Mice; D008854:Microscopy, Electron; D010010:Osteoclasts / Q000166:cytology*; D011247:Pregnancy; D012886:Skull / Q000166:cytology
chemical_list: D017886:Durapatite