Study of in vivo differentiation of rat bone marrow stromal cells into Schwann cell-like cells

In order to raise an abundant and accessible reservoir for Schwann cells (SCs), which are used as seed cells for constructing tissue-engineered nerve grafts, we investigated the feasibilty of in vivo differentiation of bone marrow stromal cells (MSCs) into SC-like cells. In this study, MSCs were harvested from adult rats' bone marrow, culture-expanded, and characterized. Subcultured MSCs were then labeled with Hoechst 33342, followed by transplantation into the nerve regeneration chamber, which was made of a silicone tube bridging the sciatic nerve defect of the rats. Four weeks after surgery, some of the differentiated MSCs turned into SC-like cells immunopositive to S-100 protein, accompanied by myelination of the regenerated nerve fibers. Walking-track analyses provided evidence that transplantation of MSCs contributed to reconstruction of the sciatic nerve and reinnervation of target tissues. The experimental results suggest that MSCs are capable of differentiating into SC-like cells in vivo, making them a promising candidate for cell transplantation in peripheral nerve repair. (c) 2006 Wiley-Liss, Inc.