title: Effects of setting bone cement on tissue-engineered bone graft: a potential barrier to clinical translation?
abstract: BACKGROUND
  Strategies to improve mechanical strength, neovascularization, and the regenerative capacity of allograft include both the addition of skeletal stem cells and the investigation of novel biomaterials to reduce and ultimately obviate the need for allograft altogether. Use of bone cement is a common method of stabilizing implants in conjunction with impacted allograft. Curing cement, however, can reach temperatures in excess of 70°C, which is potentially harmful to skeletal stem cells. The aim of this study was to investigate the effects of setting bone cement on the survival of human adult skeletal stem cells within tissue-engineered allograft and a novel allograft substitute.
  
  
  METHODS
  Milled allograft and a polymer graft substitute were seeded with skeletal stem cells, impacted into a graduated chamber, and exposed to curing bone cement. Sections were removed at 5-mm increments from the allograft-cement interface. A quantitative WST-1 assay was performed on each section as a measure of remaining cell viability. A second stage of the experiment involved assessment of methods to potentially enhance cell survival, including pretreating the allograft or polymer by either cooling to 5°C or coating with 1% Laponite, or both.
  
  
  RESULTS
  There was a significant drop in cellular activity in the sections taken from within 0.5 cm of the cement interface in both the allograft and the polymer (p < 0.05), although there was still measurable cellular activity. Pretreatment methods did not significantly improve cell survival in any group.
  
  
  CONCLUSIONS
  While the addition of bone cement reduced cellular viability of tissue-engineered constructs, this reduction occurred only in close proximity to the cement and measurable numbers of skeletal stem cells were observed, confirming the potential for cell population recovery.
authors.affiliation: Bone and Joint Research Group, Human Development and Health, University of Southampton Medical School, Tremona Road, Southampton UK. edwardtayton@hotmail.com
authors.forename: Edward R
authors.initials: ER
authors.lastname: Tayton
authors.forename: James O
authors.initials: JO
authors.lastname: Smith
authors.forename: Nicholas
authors.initials: N
authors.lastname: Evans
authors.forename: Alex
authors.initials: A
authors.lastname: Dickinson
authors.forename: Alexander
authors.initials: A
authors.lastname: Aarvold
authors.forename: Spandan
authors.initials: S
authors.lastname: Kalra
authors.forename: Matthew
authors.initials: M
authors.lastname: Purcell
authors.forename: Steven
authors.initials: S
authors.lastname: Howdle
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Dunlop
authors.forename: Richard O C
authors.initials: RO
authors.lastname: Oreffo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001843:Bone Cements; D018786:Bone Substitutes; D016025:Bone Transplantation; D018929:Cell Culture Techniques; D002470:Cell Survival; D017886:Durapatite; D006801:Humans; D008297:Male; D011091:Polyesters; D013234:Stem Cells / Q000502:physiology*; D023822:Tissue Engineering; D054457:Tissue Scaffolds
chemical_list: D001843:Bone Cements; D018786:Bone Substitutes; D011091:Polyesters; C499699:hydroxyapatite-polylactide; D017886:Durapatite