Mesenchymal stem cell ingrowth and differentiation on coralline hydroxyapatite scaffolds

Culture of osteogenic cells on a porous scaffold could offer a new solution to bone grafting using autologous human mesenchymal stem cells (hMSC) from the patient. We compared coralline hydroxyapatite scaffolds with pore sizes of 200 and 500 mu m for expansion and differentiation of hMSCs. We cultivated the hMSC statically or in spinner flasks for 1, 7, 14 and 21 days and found that the 200-mu m pore scaffolds exhibited a faster rate of osteogenic differentiation than did the 500-mu m pore scaffolds as shown by an alkaline phosphatase activity assay and real-time reverse transcriptase polymerase chain reaction for 10 osteogenic markers. The 500-mu m scaffolds had increased proliferation rates and accommodated a higher number of cells (shown by DNA content, scanning electron microscopy and fluorescence microscopy). Thus the porosity of a 3D microporous biomaterial may be used to steer hMSC in a particular direction. We found that dynamic spinner flask cultivation of hMSC/scaffold constructs resulted in increased proliferation, differentiation and distribution of cells in scaffolds. Therefore, spinner flask cultivation is an easy-to-use inexpensive system for cultivating hMSCs on small to intermediate size 3D scaffolds. (c) 2006 Elsevier Ltd. All rights reserved.