Peripheral nerve regeneration by bone marrow stromal cells.

Adult bone marrow contains stem cells that have attracted interest through their possible use for cell therapy in neurological diseases. Bone marrow stromal cells (MSCs) were harvested from donor adult rats, cultured and pre-labeled with bromodeoxyuridine (BrdU) previously to be injected in the distal stump of transected sciatic nerve of the rats. Distal nerve stump of control rats received culture medium solution. MSCs-treated rats exhibit significant improvement on walking track test at days 18 and 33 compared to controls. Dual immunofluorescence labeling shows that BrdU reactive cells survive in the injected area of transected sciatic nerve at least 33 days after implantation, and almost 5% of BrdU cells express Schwann cell-like phenotype (S100 immunoreactivity). Because MSCs injected in a lesioned peripheral nerve can survive, migrate, differentiate in Schwann cells, and promote functional recovery, they may be an important source for cellular therapy in several neurological diseases.