Osteoblastic differentiation of rabbit mesenchymal stem cells loaded in A carrier system of Pluronic F127 and Interpore.

Background: Ideally, bone tissue engineering products should have the ability of osteoconduction and osteoinduction. According to the tissue engineering principle, mesenchymal stem cells (MSCs) combined with an appropriate scaffold can be used as a bone substitute for bone defects. Here we used Interpore as a scaffold loaded with MSCs mixed in hydrogel (Pluronic F127). In order to demonstrate the osteogenic ability of MSCs in the hydrogel, cell/hydrogel scaffold constructs were cultured in an induction medium to elicit an osteoblastic response.

Methods: MSCs aspirated from rabbit bone marrow were cultured in induction medium. MSCs were then loaded into scaffold Interpore with the aid of hydrogel (Pluronic F127). After culture for 7 and 14 days, osteoblastic differentiation ability was tested using Alizarin Red S stain, reverse transcription polymerase chain reaction (RT-PCR), measurement of calcium and alkaline phosphatase levels, and scanning electron microscopy (SEM).

Results: Calcium and alkaline phosphatase levels both increased after 7 and 14 days incubation. Alizarin Red S staining revealed MSCs could survive and differentiate to osteoblasts in the cell/hydrogel scaffold. RT-PCR showed mRNA expression of osteopontin and Core binding factor alpha 1 (Cbfa1). SEM revealed growth of osteoblast-like cells on ceramic pores.

Conclusions: Osteoconductive bone substitute (Interpore) has been used clinically for a long time. This study showed that MSCs could be held on Interpore with the aid of hydrogel (Pluronic F127) and that they could differentiate to osteoblasts.