title: The posterior iliac crest outperforms the anterior iliac crest when obtaining mesenchymal stem cells from bone marrow.
abstract: BACKGROUND
  The clinical application of freshly isolated connective-tissue progenitors, as well as the potential preparation of culture-expanded mesenchymal stem cell populations for therapeutic applications, will benefit from clinical methods that maximize the yield of the starting population. We compared the number of cells, concentration, and prevalence of colony-founding connective-tissue progenitors from the anterior and posterior iliac crest. In addition, we compared the expansion kinetics and multilineage differentiation potential of their culture-expanded progeny when processed to form mesenchymal stem cells.
  
  
  METHODS
  Marrow aspirate was collected from both the anterior and posterior iliac crest of twenty-two patients. The concentration and prevalence of colony-founding connective-tissue progenitors were estimated with use of a colony formation assay. The expansion kinetics and multilineage differentiation potential of the culture-expanded mesenchymal stem cell populations derived from these starting samples were compared.
  
  
  RESULTS
  The yield of colony-founding connective-tissue progenitors was 1.6 times greater in the posterior compared with the anterior iliac crest. No differences were found with respect to the viability, phenotype, expansion kinetics, or multilineage differentiation potential of mesenchymal stem cell populations derived from these two sites.
  
  
  CONCLUSIONS
  The concentration and yield of colony-founding connective-tissue progenitors were greater when aspirate was obtained from the posterior compared with the anterior iliac crest, whereas the biological potential of the cells derived from these sites appeared comparable.
  
  
  CONCLUSIONS
  The harvesting of bone marrow from the posterior iliac crest appears to be preferred, as it provided a modestly higher concentration of colony-founding connective-tissue progenitors than comparable aspirate from the anterior iliac crest.
authors.affiliation: Osteoarticular Regeneration Laboratory, 2nd Clinic of Orthopaedics and Traumatology, Rizzoli Orthopaedic Institute, Bologna, Italy. michela.pierini@ior.it
authors.forename: Michela
authors.initials: M
authors.lastname: Pierini
authors.forename: Claudia
authors.initials: C
authors.lastname: Di Bella
authors.forename: Barbara
authors.initials: B
authors.lastname: Dozza
authors.forename: Tommaso
authors.initials: T
authors.lastname: Frisoni
authors.forename: Elisa
authors.initials: E
authors.lastname: Martella
authors.forename: Chiara
authors.initials: C
authors.lastname: Bellotti
authors.forename: Daniel
authors.initials: D
authors.lastname: Remondini
authors.forename: Enrico
authors.initials: E
authors.lastname: Lucarelli
authors.forename: Sandro
authors.initials: S
authors.lastname: Giannini
authors.forename: Davide
authors.initials: D
authors.lastname: Donati
mesh_terms: D000328:Adult; D001853:Bone Marrow; D002452:Cell Count; D002454:Cell Differentiation; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007085:Ilium / Q000166:cytology*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells; D010641:Phenotype; D020858:Tissue and Organ Harvesting / Q000379:methods*; D060053:Transplant Donor Site