Osteoblast-like cellular response to dynamic changes in the ionic extracellular environment produced by calcium-deficient hydroxyapatite

  • J. Gustavsson
  • M. P. Ginebra
  • J. Planell
  • E. EngelEmail author


Solution-mediated reactions due to ionic substitutions are increasingly explored as a strategy to improve the biological performance of calcium phosphate-based materials. Yet, cellular response to well-defined dynamic changes of the ionic extracellular environment has so far not been carefully studied in a biomaterials context. In this work, we present kinetic data on how osteoblast-like SAOS-2 cellular activity and calcium-deficient hydroxyapatite (CDHA) influenced extracellular pH as well as extracellular concentrations of calcium and phosphate in standard in vitro conditions. Since cells were grown on membranes permeable to ions and proteins, they could share the same aqueous environment with CDHA, but still be physically separated from the material. In such culture conditions, it was observed that gradual material-induced adsorption of calcium and phosphate from the medium had only minor influence on cellular proliferation and alkaline phosphatase activity, but that competition for calcium and phosphate between cells and the biomaterial delayed and reduced significantly the cellular capacity to deposit calcium in the extracellular matrix. The presented work thus gives insights into how and to what extent solution-mediated reactions can influence cellular response, and this will be necessary to take into account when interpreting CDHA performance both in vitro and in vivo.


Calcium Deposition Regular Medium Osteogenic Medium Osteogenic Factor Cellular Capacity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Funding was obtained from the European Commission for projects NMP3-CT-2005-013912 and NMP-LA-2008-214402. J. G. acknowledges FI grant from the Generalitat de Catalunya. Support for the research by M. P. G. was received through the prize “ICREA Academia” for excellence in research, funded by the Generalitat de Catalunya.


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • J. Gustavsson
    • 1
    • 2
    • 3
  • M. P. Ginebra
    • 2
    • 3
  • J. Planell
    • 1
    • 2
    • 3
  • E. Engel
    • 1
    • 2
    • 3
    Email author
  1. 1.Institute for Bioengineering of Catalonia (IBEC)BarcelonaSpain
  2. 2.Department of Materials Science and Metallurgy, Biomaterials, Biomechanics and Tissue Engineering GroupTechnical University of Catalonia (UPC)BarcelonaSpain
  3. 3.Biomedical Research Networking Center in Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN)ZaragozaSpain

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