干细胞的研究进展

在美国《Ｓｃｉｅｎｃｅ》杂志评选出的１９９９年度１０大科学进展中，干细胞（ｓｔｅｍ ｃｅｌｌ， ＳＣ）的研究工作格外令人瞩目。这不仅因为在过去短短的一年里，科学家们在干细胞的功能研究方面发表了１０余篇具有里程碑意义的论文，更重要的是，这些突破性进展使得生物学家和医学家们更进一步地认识到：ＳＣ作为一类既有自我更新能力、又有多分化潜能的细胞，具有非常重要的理论研究意义和临床应用价值［１］。这些成果一方面揭示了许多有关细胞生长和发育的基础理论难题；另一方面，可望将其用于创伤修复、神经再生和抗衰老等临床医…     

干细胞移植治疗肝脏疾病的研究进展

背景：干细胞移植治疗肝病是近年来众多学者研究的热点,干细胞移植的基本理论和临床应用研究都取得了很大的进展。 目的：对干细胞移植的理论依据、干细胞来源、移植方式、实验与临床研究、存在问题及前景进行简要综述。 方法：应用计算机检索中国学术期刊全文数据库(CNKI)和Pubmed数据库中2001-01/2011-11关于干细胞移植治疗肝病的文章,检索主题词“干细胞,移植,肝脏疾病,肝损伤”或“stem cell,transplantation,hepatic disease, hepatic injury”。初检索到192篇文献,据纳入标准保留31篇进行分析、综述。 结果与结论：干细胞来源充足,容易获取,可以体外增殖培养,干细胞移植操作简单,安全性高,尤其自体干细胞移植可完全避免移植排斥反应。但自体干细胞移植肝脏疾病的安全性和有效性尚无公识,需更长期的观察。     

胚胎神经干细胞移植治疗阿尔茨海默病

BACKGROUND:More recently, stem cell therapy has become an issue of concern. Exogenous neural stem cell transplantation brings new hope for the treatment of nervous system injury by self-replication and differentiation to complement and replace damaged or dead nerve cells. OBJECTIVE:To explore the therapeutic efficacy of neural stem cell transplantation on Alzheimer’s disease. METHODS:Thirty APP/PS1 mice with Alzheimer’s disease were randomly assigned into model group, cell solution transplantation group or cell transplantation group (n=10 per group). Another 10 C57BL/6 mice were selected as controls. Embryos of C57BL/6 mice at 18 embryonic days were taken to make neural stem cell suspension followed by transfection using lentiviral vectors carrying GFP gene at different multiplicities of infection (1, 5, 10, 15, 20). Afterwards, GFP-transfected neural stem cells were implanted into the hippocampus of Alzheimer’s disease mice in the cell transplantation group, while the same volume of complete medium was injected into the hippocampus of mice in the cell solution transplantation group. Morris water maze test was performed at 2 weeks after cell transplantation, and brain tissues of mice was taken and detected histologically at 4 weeks after cell transplantation. RESULTS AND CONCLUSION:Compared with the control group, the escape latency was significantly higher, and the number of crossings over the target quadrant was lower in the other three groups (P < 0.05). Compared with the cell solution transplantation and model groups, in contrast, the escape latency was significantly lower, and the number of crossings over the target quadrant was significantly higher in the cell transplantation group (P < 0.05). Four weeks after transplantation, more intact neurons were found in the cell transplantation group as compared with the model group. These findings indicate that neural stem cell transplantation can improve behavior and morphology performance of mice with Alzheimer’s disease.     

干细胞移植治疗系统性硬化的研究进展

系统性硬化(systemic sclerosis,SSc)的治疗一直是临床上的难题,现有的治疗手段难以满足患者需求。造血干细胞移植(hematopoietic stem cell transplantation,HSCT)在临床上的发展已相对成熟,近年来其在SSc上的临床试验取得了突破进展,但移植相关并发症问题一直有待...     

神经干细胞移植治疗老年痴呆

BACKGROUND:Neural stem cell transplantation has been used to treat a series of brain injury diseases, such as cerebral palsy, but its effect on Alzheimer’s disease is rarely reported. OBJECTIVE:To observe the effect of neural stem cell transplantation on the behavior and immune regulating system of Alzheimer’s disease rats.  METHODS:Thirty-five Sprague-Dawley rats were enrolled to make a postcerebral incision and given hippocampal injection of amanita phalloides acid to establish rat models of Alzheimer’s disease. Another 10 rats were only given hippocampal injection of normal saline after preparation of postcerebral skin incision as sham operation group. Then 32 successful rat models were randomly divided into two groups (n=16 per group): rats in experimental group were administrated hippocamal injection of 5×109/L allogeneic neural stem cell suspension; those in model group were given no injection. Five-day Morris water maze test was conducted at 4 weeks after transplantation. At 1 week after Morris water maze test, levels of interleukin-1 and interleukin-10 in the cerebral homogenate were detected, as well as pathological changes of brain tissues were observed in the three groups. RESULTS AND CONCLUSION:Compared with the model group, the abilities of cognition and memory were significantly higher in the sham operation group (P < 0.01), and the abilities of spatial learning and memory were significantly higher in the experimental group (P < 0.05, P < 0.01). Levels of interleukin-1 and interleukin-10 in the model group were significantly higher than those in the sham operation group (P < 0.01) but significantly lower than those in the experimental group (P < 0.01). Besides, the number of neurons in the model group was obviously less than that in the experimental and sham operation group. These results indicate that neural stem cell transplantation supplements and protects neurons against Alzheimer's disease in rats, thereby significantly improving the learning and memory ability.     

同基因与异基因胚胎肝干细胞移植治疗小鼠肝硬化

背景：胚胎肝干细胞移植免疫相关研究较少,同基因与异基因胚胎肝干细胞移植对小鼠肝硬化的治疗作用,目前尚不清楚。 目的：观察同种同基因与同种异基因胚胎肝干细胞移植对小鼠肝硬化的治疗作用,以及治疗过程中免疫排斥反应发生情况。 方法：采用Ⅳ型胶原酶消化法分离纯化BALB/c与C57BL/6胚胎肝干细胞。104只健康BALB/c小鼠随机分为4 组：正常对照组不予任何处理;肝硬化组、同种同基因移植组、同种异基因移植组腹腔注射四氯化碳石蜡油溶液复制肝硬化模型,16周后分别经其尾静脉注射生理盐水,等量同种同基因胚胎肝干细胞和同种异基因胚胎肝干细胞。在移植4周后比较各组受体小鼠存活情况、肝功能恢复情况、肝纤维化程度、免疫细胞(CD4⁺T、CD8⁺T、NK、NKT)数目及比值、肝脏病理学变化。 结果与结论：同种同基因移植组和同种异基因移植组生存率均为100%,与肝硬化组小鼠存活率67%相比差异有显著性意义(P < 0.05);各组肝功能和肝纤维化指标差异无显著性意义(P > 0.05)。各组免疫学指标比较差异无显著性意义(P > 0.05)。肝脏组织病理学显示肝组织修复：同种异基因移植组>同种同基因移植组>肝硬化组。因此,经尾静脉移植胚胎肝干细胞能提高肝硬化小鼠的生存率、减轻肝细胞坏死程度;同种同基因与同种异基因胚胎肝干细胞移植未发现免疫排斥,对小鼠肝硬化有一定的治疗作用。     

自体骨髓干细胞移植治疗肝硬化的疗效观察

治疗终末期肝病,原位肝移植是最理想的手段,然而供体短缺、手术损伤大、术后的免疫排斥反应以及费用高昂等问题限制了肝移植技术的发展和临床应用。自体骨髓干细胞移植操作简便、有效、侵入性小且并发症少,具有重要的临床意义。我科2009年9月至2011年1月共收治严重肝硬化失代偿期患者8例,经自体骨髓干细胞移植,治疗效果良好     

干细胞移植治疗心肌坏死的基础与临床研究

干细胞治疗心肌坏死是一种新的很有前景的治疗手段,但其机制尚不十分清楚。我国目前临床研究发现干细胞移植可以明显改善急性心肌梗死及梗死后心衰心脏功能,但由于关于干细胞移植的安全性还没有定论,因此还需慎重对待。     

糖原合成酶激酶3β过表达心肌干细胞移植治疗心肌梗死

BACKGROUND:The mechanism and effect of glycogen synthase kinase 3β (GSK-3β) in the differentiation of cardiac stem cells into cardiomyocytes are still unclear, although GSK-3β is closely related to the life activities of cells. OBJECTIVE:To investigate the changes of GSK-3β expression in the treatment of myocardial infarction in rats undergoing cardiac stem cell transplantation. METHODS:The isolation and culture of cardiac stem cells were performed in 10 neonatal rats. Lentivirus overexpressing GSK-3β or LacZ (control) was constructed and transferred into cardiac stem cells. Animal model of myocardial infarction was made in 30 Sprague-Dawley rats. Six weeks after model preparation, rat models were assigned into GSK-3β, LacZ or PBS group. GSK-3β or LacZ overexpressing cardiac stem cell solution or PBS in equal volume was injected into the rat myocardium, respectively. Four weeks after transplantation, the cardiac function and myocardial collagen production in rats were detected and compared. RESULTS AND CONCLUSION:Compared with the other two groups, the left ventricular ejection fraction was significantly higher, and the left ventricular end diastolic diameter was significantly lower in the GSK-3β group (P < 0.05). Hydroxyproline content, type I collagen mRNA, and type III collagen mRNA expression were significantly lower in the GSK-3β group than the other two groups (P < 0.05). Findings from Masson staining showed that the content of blue-stained collagen was significantly lower in the GSK-3β group than the LacZ group. Moreover, lowest myocardial infarction size was found in the GSK-3β group (P < 0.05). All these experimental findings show that GSK-3 overexpression plays a positive role in promoting the therapeutic effect of cardiac stem cell transplantation.     

静脉移植骨髓间充质干细胞对心肌病心力衰竭心功能的影响

BACKGROUND:Bone marrow mesenchymal stem cell transplantation can effectively improve decreased cardiac function caused by heart failure, but there is a lack of research about the effect in bone marrow mesenchymal stem cell transplantation on cardiac function in heart failure induced by cardiomyopathies. OBJECTIVE:To explore the effect of bone marrow mesenchymal stem cell transplantation on cardiac function in patients with cardiomyopathies accompanied by heart failure. METHODS:Totally 40 Sprague-Dawley rats were enrolled, and bone marrow mesenchymal stem cells were isolated from 10 rats, and the remaining rats were equivalently randomized into normal, model and stem cell transplantation groups. Then rats in the model and stem cell transplantation groups were given intraperitoneal injection of hydrochloric acid doxorubicin to prepare cardiomyopathy-induced heart failure models. At 7 days after modeling, the stem cell transplantation group was treated with bone marrow mesenchymal stem cells through intravenous transplantation, and the model group was treated with equal amount of DMEM medium. Four weeks later, cardiac function of each rat was detected, and the cell survival and differentiation were observed by immunofluorescence method. RESULTS AND CONCLUSION:At 4 weeks after transplantation, compared with normal and stem cell transplantation groups, the left ventricular systolic pressure and maximum rise/fall rate of left ventricular pressure were significantly decreased, but the left ventricular end diastolic pressure significantly increased in the model group (P < 0.05). And there was no significant difference between the normal group and the stem cell transplantation group (P > 0.05). High and dense fluorescence intensity was observed in the host myocardium immediately after transplantation. Subsequently, the fluorescence intensity and density decreased at 4 weeks, but the cell migration could be found, and some cells expressed cardiac troponin T. These results show that intravenous transplantation of bone marrow mesenchymal stem cells can improve cardiac function in rats with heart failure due to cardiomyopathies. Besides, the transplanted cells can survive in the host, and differentiate into cardiomyocyte-like cells.     

骨髓间充质干细胞静脉移植脊髓损伤大鼠肿瘤坏死因子α及 白细胞介素1β的表达

背景：研究认为间充质干细胞的营养支持在脊髓损伤治疗中起了主要作用,其同损伤宿主神经组织间的相互作用可导致一些不利于损伤修复的炎症因子表达减少。 目的：观察大鼠骨髓间充质干细胞静脉注射移植对脊髓损伤后肿瘤坏死因子α、白细胞介素1β 表达的影响。 方法：运用改良Allen法制备大鼠T10脊髓外伤性截瘫模型,随机分为对照组和骨髓间充质干细胞移植组,设未损伤脊髓的假手术组做对照。骨髓间充质干细胞移植组、假手术组均接受大鼠骨髓间充质干细胞静脉注射移植,对照组静脉注射等量PBS。 结果与结论：对照组和骨髓间充质干细胞移植组损伤脊髓肿瘤坏死因子α、白细胞介素1β蛋白表达较假手术组有明显增加(P < 0.05);骨髓间充质干细胞移植组与对照组比较, 肿瘤坏死因子α、白细胞介素1β蛋白表达受到明显抑制(P < 0.05)。提示大鼠骨髓间充质干细胞静脉移植后能使损伤脊髓局部的肿瘤坏死因子α、白细胞介素1β表达程度降低。这可能是改变脊髓损伤区的微环境,减少脊髓继发性损伤,促进损伤大鼠运动功能恢复的机制之一。     

碱性成纤维细胞生长因子基因真核表达载体转染骨髓间充质干细胞移植治疗糖尿病

BACKGROUND:Existing studies have shown that bone marrow mesenchymal stem cells can significantly improve islet function in diabetic rats to decrease excessively high blood glucose level, which may be related to the enhancement of differentiation ability of autologou pancreatic stem cells. OBJECTIVE:To observe the therapeutic efficacy of basic fibroblast growth factor gene eukaryotic expression vector (PEGFP-C3-BFGF) transfection of bone marrow mesenchymal stem cells in diabetic rats. METHODS:Recombinant adenovirus (Ad.aFGF) mediated PEGFP-C3-BFGF was transfected into bone marrow mesenchymal stem cells, and PEGFP-C3-BFGF expression was observed using fluorescence microscopy. Eighty Sprague-Dawley rats were randomly divided into normal control group, diabetes group, transplantation group, gene transfection group, with 20 rats in each group. After modeling, rats in different groups were given portal vein injection of normal saline, PBS, 1 mL of bone marrow mesenchymal stem cell suspension, and 1 mL of PEGFP-C3-BFGF-transfected bone marrow mesenchymal stem cell suspension. RT-PCR method was used to detect mRNA expression of matrix metalloproteinases in pancreatic tissue of rats in each group. Blood glucose levels of rats were detected at 24 hours, 3, 7, 14, 21 days after transplantation. ELISA method was used to detect plasma insulin levels in rats. Pathological changes of the pancreas were observed using hematoxylin-eosin staining. RESULTS AND CONCLUSION:Under the fluorescence microscope, PEGFP-C3-BFGF transfected into cells after 48 hours showed significant specific red fluorescence. Two weeks after transplantation, matrix metalloproteinases mRNA expression was significantly increased in the diabetes group compared with the control group (P < 0.05), while it was decreased in the transplantation and gene transfection groups compared with the diabetes group (P < 0.05). After transplantation, the blood glucose levels in rats were ranked as follows: control group < gene transfection group < transplantation group < diabetes group (P < 0.05), and the plasma insulin levels in rats ranked as follows: control group > gene transfection group > transplantation group > diabetes group (P < 0.05). Pathological findings of the pancreas showed that the transplantation group was superior to the diabetes group, but inferior to the gene transfection group that was similar to the control group. All these findings indicate that PEGFP-C3-BFGF-transfected bone marrow mesenchymal stem cell transplantation can improve blood glucose levels and stimulate insulin secretion in diabetic rats, which may improve the severity of diabetes mellitus by decreasing the mRNA expression of matrix metalloproteinases.     

骨髓间充质干细胞移植治疗骨关节炎

BACKGROUND:As the ability of self-renewal, differentiation and migration into damaged tissues, bone marrow mesenchymal stem cells have been widely used in a variety of diseases. OBJECTIVE:To explore the therapeutic effect of bone marrow mesenchymal stem cell transplantation on osteoarthritis in rats. METHODS:Thirty-six Wistar rats were randomly assigned into transplantation, model or control group. osteoarthritis models were established in the transplantation and model groups, followed by tail vein injection of bone marrow mesenchymal stem cells (5×10⁷/kg) or the same volume of normal saline, respectively. Rats in the control group were subjected to no treatment. Four weeks after injection, levels of CD4⁺CD25⁺ regulatory T cells in the spleen, interleukin-17, tumor necrosis factor-α and transforming growth factor-β1 in serum were detected, and arthritis index and the degree of joint swelling were evaluated as well. RESULTS AND CONCLUSION:Compared with the control group, both arthritis index and degree of joint swelling were increased significantly in the model group (P < 0.05), but these indicators exhibited a remarkable improvement after cell transplantation (P < 0.05). Levels of CD4⁺CD25⁺ regulatory T cells in the spleen in the three groups were ranked as follows: the transplantation group > the control group > the model group. The levels of interleukin-17 and tumor necrosis factor-α in serum in the transplantation group were lower than those in the model group but higher than those in the control group (P < 0.05). Highest level of transforming growth factor-β1 was obtained in the transplantation group, followed by the control group and model group (P < 0.05). To conclude, these findings indicate that bone marrow mesenchymal stem cell transplantation exert therapeutic effects in osteoarthritis rats by immune and cytokine regulation.     

骨髓间充质干细胞移植对糖尿病模型大鼠肾脏的保护作用

BACKGROUND:So far numerous theoretical studies have shown the treatment effect of stem cell transplantation for chronic complications of diabetes, while its treatment effects on diabetic nephropathy have not yet been confirmed in animal models. OBJECTIVE:To investigate the protective effect of bone marrow mesenchymal stem cell transplantation on the kidney in rat models of diabetes. METHODS:Rats were fed with high-sugar and high-fat diet for 4 weeks, and then were given injection of streptozotocin to establish type 2 diabetic rat models. At 2 days after modeling, bone marrow mesenchymal stem cells were injected via the tail vein (stem cell transplantation group). In the meanwhile, control and diabetes groups were established. At 21 days after cell transplantation, levels of glucose, triglyceride and insulin in the tail vein were detected. Additionally, morphological observations of kidney and pancreatic tissues were performed. RESULTS AND CONCLUSION:The levels of blood sugar, insulin and triglycerides in the diabetes group were significantly higher than those of the control group (P < 0.05). Blood glucose and insulin levels in the stem cell transplantation group were significantly lower than those of the diabetes group (P < 0.05). In addition, mesangial area and glomerular volume in the stem cell transplantation group were significantly lower compared with the diabetes group (P < 0.05). These results confirm that bone marrow mesenchymal stem cell transplantation can reduce levels of blood glucose and serum insulin, contributing to the repair of damaged pancreas and kidney.     

脐血间充质干细胞移植修复急性肠缺血再灌注损伤

BACKGROUND:Bone marrow mesenchymal stem cells can repair intestinal ischemia-reperfusion injuny by interfering inflammatory reactions after intestinal ischemia-reperfusion to protect intestinal barrier functions. In recent years, umbilical cord blood mesenchymal stem cells are gradually used as a substitute source of bone marrow mesenchymal stem cells. OBJECTIVE:To investigate the effects of umbilical cord blood mesenchymal stem cells on acute intestinal ischemia-reperfusion injury. METHODS:Umbilical cord blood mesenchymal stem cells were induced, isolated in vitro and tracked by CM-DiI fluorescent labeling. Sixty-three Sprague-Dawley rats were equivalently randomized into three groups: control group received normal saline enema, intestinal ischemia-reperfusion injury group with ethanol diluted trinitro-benzene-sulfonic acid and transplantation group administrated with 1×10¹⁰/L umbilical cord blood mesenchymal stem cell suspension via the tail vein at 1 hour after trinitro-benzene-sulfonic acid modeling. At 3 days after transplantation, colon tissues were removed in each group to observe pathological changes of the intestinal tract by hematoxylin-eosin staining. Besides, expression of leptin mRNA in the colon tissues and cyclooxygenase-2 in the mucosa were detected by RT-PCR and immunohistochemistry method, respectively. RESULTS AND CONCLUSION:Transplanted umbilical cord blood mesenchymal stem cells distributed in the intestinal lymphoid tissue and among glandular epithelial cells, suggesting that these stem cells might be involved in the process of intestinal ischemia-reperfusion injury repair. Compared with the control group, intestinal injury in the injury group was significantly aggravated, and most intestinal epithelial cells shed; and the transplantation group appeared to have significantly reduced intestinal damage and significantly less cell shedding. Expression of leptin mRNA was significantly higher in the injury group than the transplantation group followed by the control group, and there were significant differences among the three groups (P < 0.05). Additionally, expression of cyclooxygenase-2 in the injury group was significantly higher than that in the control group (P < 0.05); compared with the injury group, expression of cyclooxygenase-2 was significantly lower in the transplantation group (P < 0.05). To conclude, leptin and cyclooxygenase-2 may be involved in acute intestinal ischemia-reperfusion injury, and umbilical cord blood mesenchymal stem cell transplantation significantly lessens intestinal ischemia-reperfusion injury, which provides an experimental basis for human treating acute intestinal ischemic injury.     

碱性成纤维细胞生长因子基因修饰骨髓间充质干细胞移植修复急性肾损伤

BACKGROUND:It has been confirmed that basic fibroblast growth factor (bFGF) can promote the growth, proliferation, differentiation and functional expression of most cells derived from neuroderm and mesoderm. OBJECTIVE:To investigate the effect of bFGF-transfected bone marrow mesenchymal stem cell transplantation in rats with acute kidney injury. METHODS:bFGF genes were transfected into bone marrow mesenchymal stem cells via an adenovirus vector, and then expression of bFGF in transfected cells was identified using RT-PCR technology. Rat models of acute kidney injury were prepared by clipping bilateral renal pedicles, and then randomized into three groups (n=20): rats were given injection of bone marrow mesenchymal stem cell suspensions via tail vein as negative transfected group, those given injection of bFGF-transfected bone marrow mesenchymal stem cell suspensions via tail vein as bFGF-transfected group, and the others given injection of DMEM via tail vein as model group. Four weeks later, levels of serum creatinine and urea nitrogen were detected, expressions of connective tissue growth factor and growth factor in renal tissues were detected by Western blot assay, and morphology of renal tissues was observed using hematoxylin-eosin staining. RESULTS AND CONCLUSION:bFGF genes were successfully transfected into bone marrow mesenchymal stem cells. Compared with the model group, the levels of serum creatinine and urea nitrogen were significantly reduced in bFGF-transfected and negative transfected groups, especially in the bFGF-transfected group (P < 0.05), while expressions of connective tissue growth factor and transforming growth factor in renal tissues in bFGF-transfected and negative transfected groups were significantly weakened in these two groups (P < 0.05), but there were no significant differences between the bFGF-transfected group and negative transfected group (P > 0.05). Besides, renal tissues necrosis and inflammatory reactions were mitigated in the negative transfected group; renal tubules with normal outlines and no overt necrotic cells could be found in the bFGF-transfected group. These findings show that bFGF-transfected bone marrow mesenchymal stem cell transplantation plays a better role in acute kidney injury repair in rats.     

Transwell共培养条件下诱导脂肪干细胞成骨能力的改变

BACKGROUND:Under co-culture conditions, mesenchymal stem cells could regulate osteogenic differentiation and osteogenesis of osteoblasts. OBJECTIVE:To observe the osteogenic efficiency of osteoblastic precursor cells co-cultured with undifferentiated bone marrow-derived mesenchymal stem cells, umbilical cord-derived mesenchymal stem cells, or placenta-derived mesenchymal stem cells in mineralization medium. METHODS:Adipose-derived stem cells were induced in osteogenic differentiation medium for 7 days before being indirectly co-cultured with undifferentiated mesenchymal stem cells isolated from different tissues (bone marrow group, umbilical cord group and placenta group) in Transwell plates. Induced adipose-derived stem cells cultured alone served as control group. At different experimental intervals, quantitative analysis of alkaline phosphatase activity and calcified matrix was preformed to observe the effects of mesenchymal stem cells from different sources on the osteogenic efficiency of induced adipose-derived stem cells. RESULTS AND CONCLUSION:Expression of alkaline phosphatase was significantly higher in different experimental groups than the control group (P < 0.05), and it was also higher in the bone marrow group than the umbilical cord and placenta groups (P < 0.05). Quantitative analysis of calcified matrix revealed that the experimental groups were significantly higher than the control group (P < 0.05); and in experimental groups, the umbilical cord group was higher than bone marrow group and placenta group(P < 0.05). These findings indicate that the osteogenic efficiency of induced adipose-derived stem cells is improved dramatically under co-culture conditions.     

人前脑啡肽基因修饰骨髓间充质干细胞系的生物学特性

BACKGROUND:Previous studies have found that the transplantation of modified cell lines exhibit analgesic effect. But little is reported on the biological characteristics of human preproenkephalin gene-modified bone marrow mesenchymal stem cell lines. OBJECTIVE:To observe the biological characteristics of human preproenkephalin gene-modified bone marrow mesenchymal stem cells. METHODS:Bone marrow mesenchymal stem cells were isolated and cultured to establish human preproenkephalin gene-modified bone marrow mesenchymal stem cell lines. RESULTS AND CONCLUSION:After freezing-thawing, passage 4 human bone marrow mesenchymal stem cells, human bone marrow mesenchymal stem cells-pBABE and human bone marrow mesenchymal stem cells-human preproenkephalin exhibited no significant changes in the cell viability (P > 0.05), as well as in the fat cell proportion after adipogenic induction (P > 0.05). Moreover, red calcium deposition was presented in all these cells by alizarin red staining after osteogenic induction. Flow cytometry results showed that passage 4 human bone marrow mesenchymal stem cells, human bone marrow mesenchymal stem cells-pBABE and human bone marrow mesenchymal stem cells-human preproenkephalin could express CD29 and CD44, but not express CD34 and CD45. Human preproenkephalin genes were highly expressed in human bone marrow mesenchymal stem cells-pBABE, but lowly expressed in passage 4 human bone marrow mesenchymal stem cells. Additionally, recombinant plasmid pBABE-preproenkephalin-modified human bone marrow mesenchymal stem cells could express enkephalin protein. In conclusion, human preproenkephalin gene-modified human bone marrow mesenchymal stem cell lines can maintain the pluripotent differentiation or proliferation capacity of bone marrow mesenchymal stem cells, and secrete enkephalin protein.     

骨髓间充质干细胞移植脑梗死大鼠：神经功能恢复与突触素的表达

BACKGROUND:Synaptophysin plays an important role in the recovery of neural function after cerebral ischemia. OBJECTIVE:To investigate the effects of bone marrow mesenchymal stem cell transplantation on nervous function and expression of synaptophysin after cerebral infarction. METHODS:Totally 60 rats were equivalently randomized into four groups, including sham operation, control, model and stem cell treatment groups. Rats in the control, model and stem cell treatment groups were used for preparing cerebral infarction models, and the remaining underwent the sham operation. After 1 day of modeling, bone marrow mesenchymal stem cells were transplanted into the rat lateral ventricle in the stem cell treatment group, and rats in the control group was given the injection of the same amount of PBS. After 1, 7 and 14 days of treatment, rat’s neurological function was scored on beam-walking test, rotarod test and screen test, and expression of synaptophysin was detected by RT-PCR and immunohistochemical assay. RESULTS AND CONCLUSION:At 7 and 14 days after treatment, the beam-walking test, rotarod test and screen test scores in the stem cell treatment group were significantly lower than those in the control and model groups (P < 0.05), and the above scores showed no significant differences between the control group and model group (P > 0.05). At 1 day after treatment, the mRNA expression of synaptophysin and the number of synaptophysin-positive cells in the sham operation group were significantly higher than those in the other three groups (P < 0.05); at 7 and 14 days after treatment, the mRNA expression of synaptophysin and the number of synaptophysin-positive cells in the stem cell treatment group were significantly increased compared with the other three groups (P < 0.05), and additionally, the mRNA expression of synaptophysin and the number of synaptophysin-positive cells in the sham operation group were significantly lower than those in the model and control groups (P < 0.05). These findings suggest that bone marrow mesenchymal stem cell transplantation can effectively promote the recovery of neurological function in cerebral infarction rats, and partially promote the formation of synaptophysin.     

硫酸钙人工骨复合培养骨髓间充质干细胞对骨诱导脊柱融合的影响

BACKGROUND: Biodegrable calcium sulfate artificial bone has a good biocompatibility, so it is used as a bone graft substitute in the treatment of spinal fusion. OBJECTIVE: To investigate the osteoinductive effects of the tissue-engineered bone made of bone marrow mesenchymal stem cells and calcium sulfate artificial bone in spinal fusion. METHODS: Bone marrow mesenchymal stem cells were cultured in vitro, and then combined with the calcium sulfate artificial bone. The composite material was observed under electron microscope. Totally 67 patients undergoing spinal fusion were enrolled, who were divided into control group (n=35) and observation group (n=32), receiving autologous iliac bone graft and autologous bone marrow mesenchymal stem cells combined with calcium sulfate transplantation, respectively. Subsequently, spinal fusion Lenke classification and low back outcome score were conducted. RESULTS AND CONCLUSION: Under electron microscope, the visible calcium sulfate artificial bone presented a good porous structure, on which bone marrow mesenchymal stem cells grew and adhered well. Slightly but insignificantly better outcomes in the spinal fusion through the use of the Lenke classification system were obtained in the observation group than the control group after surgery (P > 0.05). Besides, scores on low back outcomes in both two groups were significantly higher than baseline data (P < 0.05). These results suggest that the tissue-engineered bone made of calcium sulfate artificial bone as the scaffold and bone marrow mesenchymal stem cells as seed cells can exert a good osteoinduction in spinal fusion, and obtain ideal effects.