title: Means of enhancing bone fracture healing: optimal cell source, isolation methods and acoustic stimulation.
abstract: The human body has an extensive capacity to regenerate bone tissue after trauma. However large defects such as long bone fractures of the lower limbs cannot be restored without intervention and often lead to nonunion. Therefore, the aim of the present study was to assess the pool and biological functions of human mesenchymal stromal cells (hMSCs) isolated from different bone marrow locations of the lower limbs and to identify novel strategies to prime the cells prior to their use in bone fracture healing. Following, bone marrow from the ilium, proximal femur, distal femur and proximal tibia was aspirated and the hMSCs isolated. Bone marrow type, volume, number of mononuclear cells/hMSCs and their self-renewal, multilineage potential, extracellular matrix (ECM) production and surface marker profiling were analyzed. Additionally, the cells were primed to accelerate bone fracture healing either by using acoustic stimulation or varying the initial hMSCs isolation conditions.
  
  
  
  We found that the more proximal the bone marrow aspiration location, the larger the bone marrow volume was, the higher the content in mononuclear cells/hMSCs and the higher the self-renewal and osteogenic differentiation potential of the isolated hMSCs were. Acoustic stimulation of bone marrow, as well as the isolation of hMSCs in the absence of fetal bovine serum, increased the osteogenic and ECM production potential of the cells, respectively.
  
  
  
  We showed that bone marrow properties change with the aspiration location, potentially explaining the differences in bone fracture healing between the tibia and the femur. Furthermore, we showed two new priming methods capable of enhancing bone fracture healing.
authors.affiliation: MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Drienerlolaan 5, 7522NB, Enschede, The Netherlands.
authors.forename: Corina Adriana
authors.initials: CA
authors.lastname: Ghebes
authors.affiliation: MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Drienerlolaan 5, 7522NB, Enschede, The Netherlands.|Department of Orthopaedics, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
authors.forename: Maaike Vera Jasmijn
authors.initials: MV
authors.lastname: Braham
authors.affiliation: Department of Orthopedic Surgery, Medisch Spectrum Twente Hospital, Postbus 50 000, 7500KA, Enschede, The Netherlands.
authors.forename: Adelgunde Veronica Clemens Maria
authors.initials: AV
authors.lastname: Zeegers
authors.affiliation: Department of Orthopedic Surgery, Medisch Spectrum Twente Hospital, Postbus 50 000, 7500KA, Enschede, The Netherlands.
authors.forename: Auke Jan Sijbe
authors.initials: AJ
authors.lastname: Renard
authors.affiliation: MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Drienerlolaan 5, 7522NB, Enschede, The Netherlands. fernandesham@gmail.com.|Center for Neuroscience and Cell Biology (CNC), Stem Cells and Drug Screening Lab, University of Coimbra, Largo Marques de Pombal, 3004-517, Coimbra, Portugal. fernandesham@gmail.com.
authors.forename: Hugo
authors.initials: H
authors.lastname: Fernandes
authors.affiliation: MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Drienerlolaan 5, 7522NB, Enschede, The Netherlands. d.b.f.saris@utwente.nl.|Department of Orthopaedics, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands. d.b.f.saris@utwente.nl.|Faculty of Science and Technology, Institute Technical Medicine, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands. d.b.f.saris@utwente.nl.
authors.forename: Daniel B F
authors.initials: DB
authors.lastname: Saris
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D001861:Bone Regeneration / Q000502:physiology* / Q000528:radiation effects; D003131:Combined Modality Therapy / Q000379:methods; D017102:Fracture Healing / Q000502:physiology* / Q000528:radiation effects; D050723:Fractures, Bone / Q000628:therapy*; D006801:Humans; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000145:classification / Q000166:cytology*; D016896:Treatment Outcome; D014464:Ultrasonic Therapy / Q000379:methods*
keywords: Acoustic stimulation; Bone marrow; Cell priming; hMSCs