Osteogenic Differentiation of Mesenchymal Stem Cells on Polyurethane Nanocomposite Scaffold Containing Modified ClayNanoplates

Background and Aim: In regenerative medicine, a combination ofbiocompatible scaffolds, growth factors, and the cells are often usedfor the recovery of damaged tissues. Adult mesenchymal stem cells(MSCs) are attractive cell sources for new treatment strategies inregenerative medicine due to their multipotency and ease of harvest.Three-dimensional scaffolds could be used for localization, attachment,proliferation, and differentiation of stem cells. In the present study,modified clay nanoplate-polyurethane (MCNPs-PU) nanocompositescaffolds with high porosity and bimodal architectures were preparedand used to induction of osteogenic differentiation of the human adiposetissue mesenchymal stem cells (hADSCs).Methods: Gene expression in differentiated cells on MCNPs-PU and purePU scaffolds, as well as MCNPs, were analyzed by real-time RT-PCR. Inaddition, the expression of two protein markers including osteocalcinand osteopontin was investigated by immunocytochemistry (ICC) duringosteogenic differentiation of hADSCs on day 14 after induction.Results: The relative expression of five important bone-related genesincluding ALP, collagen 1, osteonectin, osteocalcin, and RUNX2was significantly enhanced by MCNPs-PU scaffolds. In addition,the expression of osteopontin and osteocalcin protein markers werequalitatively better on PU-MCNPs scaffolds compared to other groups. Itseems that the PU polymers have been able to provide a suitable porousand biocompatible scaffold for attachment, proliferation and proper celldifferentiation. It also seems that the presence of MCNPs inside the PUscaffolds has been increased the efficiency of osteogenic differentiation.Conclusion: According to the results, the PU-MCNPs scaffolds byproviding 3-D space could be a candidate substrate for bone tissueengineering and tissue repair. In addition, our findings show that thesurface modification of clay nanoplates, as well as their presence into thePU scaffolds, mediates osteoinductive and osteoconductive responsesof hADSCs. Therefore, these biocompatible nanocomposite porousscaffolds with suitable cell adhesion and proliferation as well as theability to induction of high-performance osteogenic differentiation couldbe used for bone tissue engineering purposes in the future.

کلیدواژه ها:

Osteogenic differentiation ، Mesenchymal stem cells ، Polyurethane scaffold ، Nanocomposite ، Modified clay nanoplates