OBJECTIVETo investigate the outcome of repairing pelvic autonomic nerve defects with the tissue-engineered nerve, in order to provide a new method and experimental evidence for solving sexual disturbance induced by pelvic autonomic nerve injury after radical resection of rectal carcinoma.

METHODSBone marrow stromal cells (BMSCs) were purified with density gradient centrifugation. A 10 mm defect of hypogastric nerve was created in 9 Beagle dogs and the 18 hypogastric nerves were randomly divided into three groups. Group A: nerve defects bridged with copolymer of lactic and glycolic acids (PLGA) tube containing BMSCs and collagen protein sponge. Group B: with PLGA tube only containing collagen protein sponge. Group C: with autologous nerve graft. The effect of nerve recovery was evaluated by morphology, HE staining, neurofilament immunohistochemistry staining, electron microscope scanning and measurement quantity of new axon 12 weeks after the transplantation.

RESULTSTwelve weeks after the transplantation, degradation of PLGA tubes showed in group A and group B. The nerves regenerated through defect area to distal end. The density of regeneration nerve fiber in group A and group C were better than that in group B. The difference was significant between group A or group C and group B (P<0.05), and no significant difference was observed between group A and group C(P>0.05).

CONCLUSIONTissue-engineered nerve, which is constructed by BMSCs mixed with collagen protein sponge and PLGA tube, can be used to bridge and repair the pelvic autonomic nerve defect.