ABSTRACT
In order to examine how implanted bone marrow stromal cells (BMSCs) encourage peripheral nerve regeneration, the present study investigated the interaction of BMSCs and Schwann cells (SCs) using an indirect in vitro coculture model. SCs and BMSCs were obtained from adult SpragueDawley rats. The passaged BMSCs were CD29 and CD44positive but CD45negative and were cocultured with the primary SCs using a Millicell system, which allows BMSCs and SCs to grow in the same culture medium but without direct contact. Expression of the typical SC markers S100 and glial fibrillary acidic protein (GFAP) of the treated BMSCs as well as the proliferation capacity of the cocultured SCs was evaluated by immunocytochemical staining on the 3rd and 5th day of coculture. Immunocytochemical staining showed that >75% of the BMSCs in the indirect coculture model were GFAP and S100positive on the 3rd and 5th day after coculture, as opposed to <5% of the BMSCs in the control group. On the 3rd day after coculture, only a few cocultured BMSCs showed the typical SClike morphology, while most BMSCs still kept their native appearance. By contrast, on the 5th day after coculture, almost all of the cocultured BMSCs appeared with the typical SClike morphology. Furthermore, 70.71% of the SCs in the indirect coculture model were S100positive on the 5th day of coculture, as opposed to >30.43% of the SCs in the control group. These results indicated that BMSCs may interact synergistically with SCs with regard to promoting peripheral nerve regeneration.