Zhamg Xio nin(張小寧，Dept Neurol，1st Affil Hosp Xinjiang Med Univ，Urumqi 830054)…∥Chin J Organ Transplant.－2011，32(5).－300～304

Improvement of neurological function in rats with spinal cord injury after the transplantation of neural stem cells directly differentiated from bone marrow mesenchymal stem cells

Zhamg Xio nin(張小寧，Dept Neurol，1st Affil Hosp Xinjiang Med Univ，Urumqi 830054)…∥Chin J Organ Transplant.－2011，32(5).－300～304

ObjectiveTo study the effect and mechanism of neurological function recovery in rats with spinal cord injury(SCI)rats after transplantation of neural stem cells which are directly differentiated from bone marrow mesenchymal stem cells(BMSC)，and to investigate the suitable engraftment time.MethodsBMSC at 3rd passage were differentiated into neural stem cells(NSC)，and immunofluorescence staining was used to identify

NSC.The oriented－induced cells were labeled with BrdU 3 days before they were transplanted，and they were slowly injected into the injured site of the SCI rats.The SCI rats were randomly divided into group I(transplantation at first week postinjury)，groupⅡ (transplantation at 2nd week postinjury)and control group(the operation was the same as groupⅠ，but cell suspension was replaced by equal volume of normal saline).BBB scores after transplantation were recorded.Distribution and differentiation of transplanted cells were observed by immunofluorescence staining with antibodies against BrdU combined with Nestion and Brdu combined with NF200.NF200 immunofluorescence staining was used to show regeneration of nerve fibers.Pathological changes of injured site were observed by HE staining.Results

Nestin expression was positive after BMSC were differentiated for 3 days，and if induced spherical cells were cultured continuously，different levels of NF200 and GFAP were found.BBB scores in groupⅠ and groupⅢ were significantly higher than in control group P ＜0.05，especially in groupⅠ.The immunofluorescence showed that a large number of BrdU and Nestin double－positive cells and some Brdu and NF200 double－positive cells filled the injured site and linked the two sides of the injured area in groupⅠ and groupⅡ，and the lesion area of spinal cord was reduced as compared with control group P ＜0.05.More importantly，further reduction in lesion area and improvement in neurological function were observed in groupⅠ.ConclusionBMSC can be differentiated into NSC.Ttransplantation of NSC could effectively promote g nerve function recovery after SCI，and the effect of transplantation at first week postinjury was better than at 2nd week postinjury.13 refs，3figs，1 tab.

(Authors)