title: Comparison of lumbar spine fusion using mixed and cloned marrow cells.
abstract: METHODS
  Prospective study on lumbar spine fusion using cloned and mixed marrow cells.
  
  
  OBJECTIVE
  To analyze the effectiveness of cloned osteoprogenitor cells in spine fusion and their differentiation in vivo using a traceable gene.
  
  
  BACKGROUND
  Although autografts are currently the standard for stable spine fusion, supply is limited. Alternative graft materials need to be developed and evaluated.
  
  
  METHODS
  An osteoprogenitor cell, D1-BAG, cloned from mouse bone marrow and transduced with LacZ and neomycin resistance genes, and mixed marrow stromal cells from marrow blowouts were used in athymic rats to establish posterior spinal fusion; 2 x 10(6) cells in 100 microL Matrigel were implanted into the lumbar fusion bed in 36 animals, whereas Matrigel without cells was used in 16 animals as control. Rats were killed at 2, 3, 6, and 9 weeks, and the spines were evaluated by manual palpation, radiographs, and histology.
  
  
  RESULTS
  Two weeks after surgery radiopaque tissue was seen at transplantation sites with D1-BAG cells but not at sites with mixed marrow stromal cells. Successful spine fusion at 6 and 9 weeks was observed in 8 of 8 (100%) animals receiving DI-BAG cells, 4 of 8 (50%) in mixed marrow stromal cells, and 0 of 8 (0%) in control animals.
  
  
  CONCLUSIONS
  Compared with mixed marrow stromal cells, cloned osteoprogenitor cells can produce a larger amount of mature osseous tissue at an earlier time point during spine fusion.
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA. qc4q@virginia.edu
authors.forename: Q
authors.initials: Q
authors.lastname: Cui
authors.forename: Z
authors.initials: Z
authors.lastname: Ming Xiao
authors.forename: G
authors.initials: G
authors.lastname: Balian
authors.forename: G J
authors.initials: GJ
authors.lastname: Wang
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D016026:Bone Marrow Transplantation; D002999:Clone Cells / Q000166:cytology / Q000637:transplantation*; D004352:Drug Resistance, Microbial / Q000235:genetics; D018380:Hematopoietic Stem Cell Transplantation; D007763:Lac Operon / Q000235:genetics; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D051379:Mice; D008807:Mice, Inbred BALB C; D009355:Neomycin / Q000378:metabolism; D010006:Osteoblasts / Q000166:cytology / Q000637:transplantation; D011859:Radiography; D051381:Rats; D011923:Rats, Nude; D017207:Rats, Sprague-Dawley; D016037:Single-Blind Method; D013123:Spinal Fusion / Q000379:methods*; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology; D017154:Stromal Cells / Q000166:cytology / Q000637:transplantation; D014161:Transduction, Genetic
chemical_list: D009355:Neomycin