title: Viable cells survive in fresh frozen human bone allografts.
abstract: BACKGROUND
  Fresh frozen bone allograft is available for human recipients after at least 6 months of quarantine at -80 degrees C. It is assumed that cryopreservation without cryoprotectant removes all viable donor cells.
  
  
  METHODS
  We studied the in vitro cell growth from samples of fresh frozen human femoral head allografts after they had been released for patient use, and compared it with cell growth from a control group of fresh cancellous bone specimens from excised femoral heads (8 samples in each group).
  
  
  RESULTS
  Cell outgrowths were seen in all of the fresh cancellous bone specimens (100% of replicates, 48 replicates per specimen) but only in a small minority of replicates from 4 of the allograft samples (mean 3.1%). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) investigations revealed that cell outgrowths from both groups contained mRNA for transcription factors Runx2 and Osterix, and also for matrix proteins collagen type I, osteocalcin and bone sialoprotein. This is consistent with the cells being osteoblast-related.
  
  
  CONCLUSIONS
  This study confirms that fresh frozen human bone allograft cells have the potential to grow in vitro, but the significance of this in recipients is currently unknown.
authors: Institute of Science and Technology in Medicine, University of Keele, the Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry, Shropshire, UK. Simsquash@aol.com
authors: David
authors: D
authors: Simpson
authors: Gopikrishna
authors: G
authors: Kakarala
authors: Karen
authors: K
authors: Hampson
authors: Niall
authors: N
authors: Steele
authors: Brian
authors: B
authors: Ashton
mesh_terms: D016025:Bone Transplantation / Q000502:physiology; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured / Q000166:cytology / Q000502:physiology; D015925:Cryopreservation; D005270:Femur Head / Q000166:cytology; D015870:Gene Expression; D006801:Humans; D066298:In Vitro Techniques; D012313:RNA / Q000032:analysis; D013997:Time Factors; D014184:Transplantation, Homologous
chemical_list: D012313:RNA