Direct and indirect effects of microstructured titanium substrates on the induction of mesenchymal stem cell differentiation towards the osteoblast lineage.

Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, GA 30332-0363, USA.
Biomaterials (Impact Factor: 8.31). 04/2010; 31(10):2728-35. DOI: 10.1016/j.biomaterials.2009.12.029
Source: PubMed

ABSTRACT Microstructured and high surface energy titanium substrates increase osseointegration in vivo. In vitro, osteoblast differentiation is increased, but effects of the surface directly on multipotent mesenchymal stem cells (MSCs) and consequences for MSCs in the peri-implant environment are not known. We evaluated responses of human MSCs to substrate surface properties and examined the underlying mechanisms involved. MSCs exhibited osteoblast characteristics (alkaline phosphatase, RUNX2, and osteocalcin) when grown on microstructured Ti; this effect was more robust with increased hydrophilicity. Factors produced by osteoblasts grown on microstructured Ti were sufficient to induce co-cultured MSC differentiation to osteoblasts. Silencing studies showed that this was due to signaling via alpha2beta1 integrins in osteoblasts on the substrate surface and paracrine action of secreted Dkk2. Thus, human MSCs are sensitive to substrate properties that induce osteoblastic differentiation; osteoblasts interact with these surface properties via alpha2beta1 and secrete Dkk2, which acts on distal MSCs.

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    ABSTRACT: Objective To explore decreased proliferation ability and differentiation potential of mesenchymal stem cells (MSCs) of osteoporosis rat. Methods MSCs were obtained from osteoporosis rat, and proliferation potency and impaired osteogenic differentiation potential were determined. Results The result showed a significant downregulation of MSCs pluripotency related gene (Oct 4) and osteogenic genes (BSP, OCN) expression in OVX MSCs compared with Sham MSCs (P<0.05). Conclusions These data suggest that MSCs are aging in osteoporosis body, and autologous OVX MSCs transplantation is not appropriate to treat osteoporosis if necessary. There will be a possibility in establishing a new clinical application of MSCs autologous transplantation to treat osteoporosis, if OVX MSCs have stronger proliferation and differentiation.
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    ABSTRACT: Citation: Khan MR, Donos N, Salih V, Brett PM (2014) Receptor Kinase AXL is Modulated in the Osteogenic Differentiation of Human Mesenchymal Stromal Cells on Modified Titanium Implant Surfaces. J Stem Cell Res Ther 4: 233. Copyright: © 2014 Khan MR, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
    Journal of Stem Cell Research and therapy. 09/2014; 4(9).

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