Transplantation of neural precursors derived from embryonic stem cells for repairing spinal cord injury
- VernacularTitle:来源于胚胎干细胞的神经前体细胞移植修复脊髓损伤
- Author:
Jianhua YANG
;
Fenghua WANG
;
Changde LI
;
Yu WANG
;
Jie MA
- Publication Type:Journal Article
- From:
Chinese Journal of Tissue Engineering Research
2007;11(24):4842-4846
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: Embryonic stem cells can be induced to differentiate into neural precursors under certain conditions, and they can effectively integrate with host cells after transplanted into healthy or injured central nervous system, and then repair and rebuild the injured nerve tissue.OBJECTIVE: To observe the effects of transplantation of neural precursors induced by embryonic stem cells on the recovery of neurological function in mice with spinal cord injury.DESIGN: A randomized controlled animal trial.SETTING: Research Center of Developmental Biology, Shanghai Second Medical University.MATERIALS: Twenty-eight C57/BL6J mice of 6-8 weeks old, both sexes, were used. Mice embryonic stem cell strain S8 and carrier LacZ labeling genes were provided by Shanghai Research Center of Developmental Biology. High-glucose Dulbecco's modified Eagle media (DMEM), β-mercaptoethanol (BME), mice leukemia inhibitory factor (LIF) and mitocin-C were all from GIBCO attachment induction medium, which were provided by Shanghai Research Center of Developmental BiologyMETHODS: The experiment was carried out in the central laboratory of developmental biology of Shanghai Second Medical University from April 2003 to April 2004. The embryonic stem cells were cultured and induced to differentiate into neural precursors by means of attachment induction. The mice were anesthetized and made into models of spinal cord hemisection on the T9-T10 plan. The mice were randomly divided into three groups: sham operated group (n =9): Only T9-T10 spinous process and corresponding lamina of vertebra were removed, then the skin was sutured layer by layer;ransplantation group (n =10): After spinal cord hemisection, embryonic stem cells were injected into the vertebral canal about 1 cm away from the injured site; model group (n =9): DMEM was injected into the region around the injured site.The mice were evaluated with Basso, Beattie, Bresnahan (BBB) locomotor rating scale to observe the recovery of neurological function at 1, 2, 4, 6 and 8 weeks (the score ranged from 1 to 21 points, the higher the scores, the better the recovery of neurological function). At 8 weeks, the survival and differentiation of embryonic stem cells at the injured site of spinal cord were observed using X-Gal staining in each group. The positively stained sections with X-Gal at the injured site of spinal cord were detected with fluorescent immunohistochemical staining.MAIN OUTCOME MEASURES: ① Recovery of neurological function; ② Survival and differentiation of embryonic stem cells at the injured site of spinal cord; ③ Results of fluorescent immunohistochemical staining.RESULTS: ① The BBB scores in the transplantation group at 1, 2 and 4 weeks were higher than those in the model group (P ＜ 0.01). ② Survival and differentiation of embryonic stem cells at the injured site of spinal cord: In the transplantation group, there were X-Gal positively stained cells in the tissue sections of the injured spinal cord of mice,the cytoplasm was blue with nucleoli in it, i.e. the cells derived from embryonic stem cells, which were not observed in the sham-operated group and model group. In the transplantation group, the cells derived from embryonic stem cells, which were implanted to the injured spinal cord, distributed around the injured sites, and integrated with the surrounding tissue and had similar form with the surrounding cells. ③ At the injured site, X-Gal positively stained cells in the transplantation group aiso expressed neurofilaments (the specific marker of neurons), but did not express GFAP.CONCLUSION:The embryonic stem cells were cultured and induced to differentiate into neural progenitors, and they could survive, migrate and differentiate into neurons after transplantation, but there was no obvious improvement of neurological function.
