Bridging small-gap peripheral nerve defects using biodegradable chitin conduits with cultured schwann and bone marrow stromal cells in rats.

Nerve regeneration requires not only an autologous, allogenous, or biodegradable scaffolding, but additional interactions with regeneration-promoting Schwann cells. Considering the pluripotency of bone marrow stromal cells into different lineages, the authors compared biodegradable conduits with the application of cultured Schwann cells and bone marrow stromal cells in a rat sciatic injury model. Simple conduit bridging served as controls. Electrophysiologic evaluation and histologic morphometrical analysis were performed after 6 weeks; both groups with cultured cells showed a statistically significantly higher number of axons, more well-shaped remyelinated axons, and an advance in clinical functional recovery (SFI) than the simple conduit-bridging group. Confocal microscopy found that bone marrow stromal cells adopted the Schwann-cell phenotype, expressing S100 protein. Considering the ease of aspiration and greater resource of bone marrow stromal cells, the implantation of a biodegradable conduit with cultured bone marrow stromal cells was capable of presenting an alternative to conduits with Schwann cells for bridging nerve defects.