Polymer-ceramic composite scaffold induces osteogenic differentiation of human mesenchymal stem cells

One of the design goals of the ideal tissue-engineered bone graft is ostoinductivity, the ability to induce the osteogenic differentiation of mesenchymal stem cells and progenitor cells. In this study, we evaluated the osteoinductive potential of a polymer-ceramic composite in vitro. This composite has been shown to be biodegradable, osteoconductive, and osteointegrative in previous studies. It is hypothesized that this composite will enhance osteoblastic differentiation in human mesenchymal stem cells (hMSCs), and that this inductive potential is substrate-dependent. Human MSCs were cultured on PLGA-BG composite scaffolds and their growth and differentiation were assessed over a four-week period. Composite scaffolds of PLGA and hydroxyapatite (HA), and hMSC cultures treated with osteogenic medium served as controls. It was found that hMSCs grown on PLGA-BG composite scaffolds expressed osteogenic markers without osteogenic media stimulation. In addition, alkaline phosphatase (ALP) activity peaked significantly earlier on the PLGA-BG composite compared to that on the PLGA scaffolds. The findings of this study collectively demonstrate the osteoinductivity of the PLGA-BG composite and its potential as a bone tissue engineering scaffold.