Role of nanofibrous poly(caprolactone) scaffolds in human mesenchymal stem cell attachment and spreading for in vitro bone tissue engineering--response to osteogenic regulators.

In this study, we evaluated the role of fiber size scale in the adhesion and spreading potential of human mesenchymal stem cells (hMSCs) on electrospun poly(caprolactone) (PCL) nanofibrous and microfibrous scaffolds. The effect of in vivo regulators in inducing osteogenic differentiation of hMSCs on PCL nanofibrous scaffolds was investigated using osteogenic differentiation marker gene expression and matrix mineralization. Here, we report for the first time the influence of in vivo regulators in an in vitro setting with hMSCs for bone tissue engineering on PCL nanofibrous matrices. Our results indicated that hMSCs attached and spread rapidly on nanofibrous scaffolds in comparison to microfibrous PCL. Further, hMSCs proliferated well on the nanofibrous scaffolds. The cells on the nanofibrous PCL were found to differentiate into the osteoblast lineage and subsequently mineralize upon addition of in vivo osteogenic regulators. The attachment and spreading of hMSCs were more effective on the nanofibers compared with the microfibers despite the lower protein surface coverage (total adsorbed protein per unit fiber surface area) on nanofibers.