慢病毒介导的CCN1基因对大鼠骨髓间充质干细胞

 目的：探讨外源性CCN1对大鼠骨髓间充质干细胞（BMSCs）生长和迁移的作用。方法：构建带有绿色荧光蛋白的大鼠CCN1慢病毒载体（Lenti-GFP-CCN1）并感染大鼠BMSCs,筛选最适感染复数（MOI）;实验分为空白组、感染Lenti-GFP组和感染Lenti-GFP-CCN1组,倒置荧光显微镜下观察BMSCs感染后荧光表达情况;MTT法检测细胞存活率,划痕愈合实验检测细胞迁移作用。结果：与空白组和阴性对照组相比,Lenti-GFP-CCN1感染大鼠BMSCs后,细胞的存活率未见明显差异;感染组细胞划痕愈合实验的愈合宽度/原宽度值与空白组及阴性对照组相比差异显著（P<0.05）。结论：外源性CCN1对正常大鼠BMSCs存活率无影响,可促进BMSCs迁移。     

骨髓间充质干细胞向神经细胞诱导分化的研究进展

骨髓间充质干细胞的研究近年来已取得了很大突破 ,由于其广泛的分化潜能及转基因的简便易行 ,已成为细胞治疗中最具发展潜力的细胞来源之一 ,具有很大的应用价值。骨髓间充质干细胞除能被诱导产生多种间充质细胞类型外 ,最近还发现它几乎不受胚层起源的限制 ,在实验动物模型或体外培养中使用特定的培养基、诱导剂 ,在一定条件下 ,即可向神经细胞和神经胶质细胞分化。未来将可能应用自体骨髓间充质干细胞诱导分化为神经细胞 ,临床治疗各种神经细胞损伤性疾病 ,应用前景广阔     

SDF-1慢病毒表达载体的构建和鉴定

基质细胞衍生因子-1(stromal cell derived factor-1,SDF-1)主要由骨髓基质细胞合成和分泌,是骨髓造血微环境的重要组成部分,在造血干细胞动员、归巢、定植和增殖中发挥重要作用,同时,可单独或协同G-CSF、TPO等细胞因子通过细胞内信号系统增强维持造血干细胞的功能,与自体外周干细胞移植后造血恢复密切相关[1].     

NK4基因慢病毒载体的构建及其在骨髓间充质干细胞中的表达

本研究构建携带人NK4基因的慢病毒载体,并将其转染人骨髓间充质干细胞(hBMSCs),明确转染后NK4表达情况。通过聚合酶链反应从HGFcDNA文库中克隆NK4基因,限制性内切酶酶切和基因重组构建慢病毒载体质粒pGC-FU-NK4,实时定量PCR检测病毒滴度。所获慢病毒(Lenti-NK4)转染hBMSCs后,荧光显微镜下观察荧光表达。ELISA检测培养上清中NK4表达。结果显示,所获NK4基因测序后与GeneBank报到序列完全一致,收集、浓缩病毒后测定其滴度为2×108TU/ml。Lenti-NK4转染hBMSCs后胞膜及胞浆有荧光分布,培养上清中NK4含量随感染时间延长而增加。提示携带NK4的慢病毒能安全、有效地转染hBMSCs,持续稳定表达。     

Oct3/4在体外诱导大鼠骨髓间质干细胞神经分化中的作用

目的: 探讨Oct3/4在体外诱导大鼠骨髓间充质干细胞(MSCs)分化为神经元中的作用。方法: 构建大鼠 Oct3/4慢病毒载体(Oct3/4 -LV)并感染大鼠MSCs;实验分为感染组(感染 Oct3/4 -LV)、阴性对照组(感染FU-PGC-NC-LV)和未感染组3组;采用β-巯基乙醇诱导各组大鼠MSCs分化为神经元。倒置荧光显微镜下观察MSCs感染后形态学变化;MTT法检测细胞存活率;免疫细胞化学法检测神经元烯醇化酶(NSE)、微管相关蛋白 2(MAP-2)、胶质纤维酸性蛋白(GFAP) 和Oct3/4的表达变化;Western blotting法检测MAP-2和Oct3/4蛋白的表达变化;RT-PCR法检测MAP-2和Oct3/4 mRNA的表达变化。结果: (1)阳性克隆PCR证明大鼠 Oct3/4 慢病毒载体构建成功,孔稀释法测定病毒滴度为2×10¹¹ TU/L。(2)倒置显微镜下观察大鼠 Oct3/4 慢病毒载体感染成功,感染复数(MOI)值为10,感染48 h时感染率最高,荧光表达最强;感染率可达83.4%±2.2%。感染组中,MSCs形态发生变化;MTT提示感染组细胞存活率显著降低(P<0.05)。(3)β-巯基乙醇可以诱导大鼠MSCs向神经元分化,其中以感染组诱导效果最佳,具有比较典型的神经元形态,NSE和MAP-2的表达率与其它各组相比显著增高(P<0.05)。(4)感染组与其它各组同时点的Oct3/4表达相比均显著增高(P<0.01)。并且随着诱导时间的延长,各组Oct3/4表达持续减少,诱导后5 h与诱导前相比存在显著差异(P<0.05)。结论: Oct3/4在大鼠MSCs分化为神经元的过程中可能起到了重要的调控作用。     

Caveolin-1在大鼠骨髓间质干细胞分化为神经细胞中的作用

目的:探讨caveolin-1在骨髓间质干细胞(MSCs)分化为神经细胞中的作用。方法:实验分为未转染组、转染组(转染Rn-caveolin-1-siRNA)、阳性对照组(转染Rn-MAPK-1control siRNA)及阴性对照组(转染negative control siRNA)4组。采用β-巯基乙醇诱导大鼠MSCs分化为神经细胞。倒置荧光显微镜下观察MSCs转染后荧光表达情况;RT-PCR检测caveolin-1和促分裂原活化蛋白激酶1(MAPK1)mRNA的表达变化;免疫细胞化学法检测caveolin-1、神经元烯醇化酶(NSE)、神经微丝亚单位(NF-M)和胶质纤维酸性蛋白(GFAP)的表达变化;MTT方法检测细胞存活率。结果:(1)siRNA转染72h,MSCs荧光表达最强,转染率可达(81.5±2.8)%;而且转染组MSCs的caveolin-1mRNA转录下降(P0.05);MTT提示转染组细胞存活率无显著变化(P0.05)。(2)β-巯基乙醇可以诱导MSCs向神经细胞分化,其中以转染组诱导效果最佳,NSE、NF-M的表达率显著高于其它各组(P0.01)。(3)随诱导时间延长,各组caveolin-1表达持续增加,诱导6d达到峰值,与诱导前、诱导6h相比有显著差异(P0.05)。此外,转染组与其它各组同时点的caveolin-1表达均显著降低(P0.01)。结论:以caveolin-1为标记蛋白的脂筏在MSCs诱导分化为神经细胞中可能起到重要的调控作用。     

新型慢病毒载体的构建及其在人骨髓间充质干细胞基因转导中的应用

背景：构建一个组成性表达某特定基因同时携带荧光报告基因和抗生素筛选基因的慢病毒载体目前未见报道。 目的：观察新型慢病毒载体pLVpuro/EF1α-PEDF-IRES-EGFP在人骨髓间充质干细胞基因转导中的表达。 方法：通过PCR在PEDF基因的两端加上attB位点,构建表达载体pLVpuro/EF1α-PEDF-IRES-EGFP,将表达载体与包装质粒(ViraPowerTM Lentiviral Packaging Mix)共转染293FT细胞。通过多次感染的方法将慢病毒载体导入人骨髓间充质干细胞,转导后第7天开始使用1~5 mg/L嘌呤霉素筛选5 d,得到表达PEDF和EGFP的人骨髓间充质干细胞,并进行Western、Elisa的鉴定分析。 结果与结论：经PCR和测序证实,慢病毒表达载体pLVpuro/EF1α-PEDF-IRES-EGFP构建成功;将其成功导入人骨髓间充质干细胞,经过筛选获得纯化的过表达PEDF基因的绿色荧光细胞群。     

慢病毒载体Pax6-EGFP构建及转染人骨髓间充质干细胞

BACKGROUND:Pax6 gene plays an important role in eye development and differentiation, and to study how it regulates the differentiation of human bone marrow mesenchymal stem cells (BMSCs), gaining the BMSCs stably over-expressing Pax6 is crucial, which is also the basis of stem cell replacement therapy. OBJECTIVE:To construct a lentivirus vector containing Pax6 and detect the expression of Pax6 in transfected human BMSCs. METHODS:Pax6 gene was extracted using PCR. After its connection with lentivirus vector pHIV-EGFP, it was then packaged by 293T cells. The human BMSCs were transfected with recombinant lentivirus Pax6-EGFP as well as lentivirus vector pHIV-EGFP, which was considered negative control group. The cellular morphology was observed by a fluorescence microscope, and the mRNA expression of Pax6 was detected by real-time PCR. RESULTS AND CONCLUSION:The recombinant lentivirus Pax6-EGFP was constructed successfully with a titer of 3×109 pfu/L. After the transfection, both the green fluorescent protein and Pax6 gene were expressed detected using fluorescence microscope and real-time PCR, showing that the method of lentiviral transfection is a safe and effective way to modify BMSCs.     

Nesprin基因RNAi慢病毒载体的构建

背景：Nesprin蛋白缺失将影响细胞骨架组织和动态平衡,引起细胞骨架刚性丧失或导致细胞过早成熟老化,其对间充质干细胞的作用如何？ 目的：构建Nesprin蛋白siRNA慢病毒载体,并转染骨髓间充质干细胞。 方法：针对Nesprin靶基因序列设计并合成4对miRNA oligo,将4种miRNA干扰质粒转入大鼠血管平滑肌细胞,筛选最有效干扰序列;将最佳干扰序列和pDONR221载体进行重组反应,获得含干扰序列的入门载体,再将入门载体和慢病毒表达目的载体pLenti6/V5-DEST进行重组反应,获得含干扰序列的慢病毒表达载体,转染包装细胞293T细胞,包装慢病毒,以293T细胞GFP蛋白水平测定病毒滴度。慢病毒转染大鼠骨髓间充质干细胞。 结果与结论：测序证实合成的4对miRNA oligo正确,RT-PCR和western-blot筛选出最佳干扰miRNA质粒为SR-3,成功构建了Nesprin siRNA的慢病毒载体LV-siNesprin。包装慢病毒,浓缩病毒悬液的活性滴度为10⁶ TU/mL。慢病毒成功了转染骨髓间充质干细胞细胞。     

骨髓间质干细胞诱导分化为神经元及其应用的研究进展

Mesenchymal stem cells (MSCs) are a population of muhipotent cells that can proliferate and differentiate into marrow and non - marrow cell types, such as adipocytes, chondrocytes, myocytes, and so on. In recent years, many researchers have studied whether MSCs are capable of differentiation into neurons in vivo and ex vivo. The result that MSCs - derived neurons express NSE and NF, but don‘t express GFAP suggests MSCs can differentiate into neurons, some researchers have achieved success in promoting functional recovery in Pakinsons and transactional spinal cord injury rat models by use of MSCs - derived neurons. Therefore, MSCs - derived neurons will play an important role in the therapy for a variety of diseases of the nervous system.     

microRNA-130b downregulation potentiates chondrogenic differentiation of bone marrow mesenchymal stem cells by targeting SOX9

Osteoarthritis (OA) is a chronic health condition. MicroRNAs (miRs) are critical in chondrocyte apoptosis in OA. We aimed to investigate the mechanism of miR-130b in OA progression. Bone marrow mesenchymal stem cells (BMSCs) and chondrocytes were first extracted. Chondrogenic differentiation of BMSCs was carried out and verified. Chondrocytes were stimulated with interleukin (IL)-1β to imitate OA condition in vitro. The effect of miR-130b on the viability, inflammation, apoptosis, and extracellular matrix of OA chondrocytes was studied. The target gene of miR-130b was predicted and verified. Rescue experiments were performed to further study the underlying downstream mechanism of miR-130b in OA. miR-130b first increased and drastically reduced during chondrogenic differentiation of BMSCs and in OA chondrocytes, respectively, while IL-1β stimulation resulted in increased miR-130b expression in chondrocytes. miR-130b inhibitor promoted chondrogenic differentiation of BMSCs and chondrocyte growth and inhibited the levels of inflammatory factors. miR-130b targeted SOX9. Overexpression of SOX9 facilitated BMSC chondrogenic differentiation and chondrocyte growth, while siRNA-SOX9 contributed to the opposite trends. Silencing of SOX9 significantly attenuated the pro-chondrogenic effects of miR-130b inhibitor on BMSCs. Overall, miR-130b inhibitor induced chondrogenic differentiation of BMSCs and chondrocyte growth by targeting SOX9.     

过表达GATA-4骨髓间充质干细胞分泌的外泌体促进骨髓间充质干细胞向心肌样细胞分化

文题释义：外泌体：是小的膜性囊泡,从20世纪90年代起受到极大关注。此词于1981年首先提出,是从细胞上产生的鳞片状脱落的囊泡,具有胞外酶的活性。外泌体所含的蛋白及miRNA可能是其生物学功能的主要部分。 小分子RNA：是一大类长度为18-25个核苷酸的小分子非编码RNA,在哺乳动物基因组中已经发现200多种小分子RNA。 背景：前期证明,过表达心脏基因转录因子GATA-4小鼠骨髓间充质干细胞分泌的外泌体(BMSCs^GATA-4- exosome)可以促进BMSCs向心肌样细胞分化,提示其可以修复心肌梗死,另外还发现BMSCs^GATA-4-exosome中及心肌梗死局部心肌组织中有miRNA-673-5p明显高表达且功能涉及细胞分化,可能是BMSCs ^GATA-4- exosome修复心肌梗死的关键分子。 目的：探讨BMSCs ^GATA-4-exosome促进BMSCs向心肌样细胞分化的分子调控网络。 方法：在小鼠BMSCs培养体系内加入miRNA-673-5p模拟物(miR-673-5p-mimic)作为实验组(BMSCs^{miR-673-5p-mimic}),将BMSCs ^GATA-4组、BMSCs ^{GATA-4-空载体}组、BMSCs组、BMSCs^{miR-673-5p-inhibitor}组作为混杂因素对照组,提取各组分泌的外泌体与BMSCs直接共培养24 h,采用免疫荧光定性检测和RT-PCR定量检测各组BMSCs中心肌特异性分子α-actin、Desmin、cTnT、Cx43的表达。根据microRNA靶基因预测结果,采用Western blot检测miRNA-673-5p对应靶基因TSC-1、ERK1/2及Mef2c转录蛋白表达。 结果与结论：BMSCs^{miR-673-5p-mimic}-exosome+BMSCs组荧光强度最强,心肌细胞特异性分子α-actin、Desmin、cTnT、Cx43的表达最高(P < 0.05),TSC-1的表达最低(P < 0.05)。结果表明BMSCs^GATA-4-exosome通过miRNA-673-5p抑制TSC-1蛋白表达促进BMSCs向心肌样细胞分化。 ORCID: 0000-0002-0219-9469(李永武) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

microRNA-1诱导大鼠骨髓间充质干细胞向心肌样细胞分化

目的研究microRNA-1(miRNA-1)能否诱导骨髓间充质干细胞(MSCs)向心肌样细胞分化。方法构建大鼠miRNA-1表达载体,分离扩增培养及鉴定大鼠MSCs。脂质体法转染大鼠第4代MSCs,实时定量RT-PCR(qRT-PCR)检测转染miRNA-1质粒后MSCs的miRNA-1表达水平。分别于转染2、4和6 d后用RT-PCR检测心肌重要转录因子GATA4、NKx2.5和MEF2C的mRNA表达,免疫荧光检测心肌特异蛋白I(cTnI)的表达。结果 90%以上的MSCs表达MSCs重要标志物CD29、CD44;未检测到造血前体细胞标志抗原CD34、白细胞标志抗原CD45的表达。转染miRNA-1质粒后,miRNA-1表达水平明显上调。转染miRNA-1质粒2、4和6 d后,GATA4、NKx2.5和MEF2C的mRNA表达逐渐增强。第4和6天后可见cTnI阳性表达细胞。结论 miRNA-1能诱导大鼠MSCs向心肌样细胞分化。     

胰岛素样生长因子-1对骨髓间充质干细胞分化类髓核细胞的作用

目的:观察不同浓度胰岛素样生长因子-1(IGF-1)对兔骨髓间充质干细胞(BMSCs)分化成类髓核细胞的作用。方法:应用3月龄新西兰大白兔骨髓和髓核进行BMSCs及髓核细胞的分离培养与鉴定;将第2代BMSCs和原代髓核细胞构建共培养体系,实验组加入不同浓度IGF-1(0、10、50、100、150μg/L)的无血清培养液诱导5、10、15、20、25 d;以10%胎牛血清的培养基单独培养BMSCs作为阴性对照。利用免疫印迹检测各组BMSCsⅡ型胶原及蛋白聚糖的表达情况。结果:100μg/L IGF-1诱导液诱导的BMSCsⅡ型胶原和蛋白聚糖蛋白水平高于对照组和其他实验组。结论:100μg/L IGF-1能提高兔BMSCs体外诱导分化成类髓核细胞的数量。     

Zfp521在大鼠骨髓间充质干细胞向神经元分化过程中的表达变化及意义

目的: 探讨锌指蛋白521(Zfp521)在大鼠骨髓间充质干细胞分化为神经元过程中的表达变化及意义。方法: 体外培养大鼠MSCs,实验分为未转染组、转染组(转染Rn-Zfp521-siRNA)和阴性对照组(转染negative control siRNA),采用β-巯基乙醇诱导骨髓间充质干细胞分化为神经元。倒置荧光显微镜下观察MSCs转染后荧光表达情况。采用免疫细胞化学法、RT-PCR法及Western blotting法检测诱导后神经元特异性烯醇化酶(NSE)和微管相关蛋白2(MAP-2)的表达情况及诱导前、后Zfp521的表达变化。结果: (1)siRNA转染72 h荧光表达最强,转染率可达84.1%±2.3%,转染组骨髓间充质干细胞的Zfp521 mRNA表达下降(P<0.05);(2)β-巯基乙醇可以诱导骨髓间充质干细胞分化为神经元,以转染组诱导效果最佳,NSE和MAP-2表达显著高于其它各组(P<0.05);(3)Zfp521在各组细胞中均有表达,诱导后Zfp521表达明显低于诱导前(P<0.01)。结论: Zfp521在大鼠骨髓间充质干细胞神经分化中表达下降,抑制Zfp521表达可促进神经元的分化,提示Zfp521在骨髓间充质干细胞的神经分化中可能发挥重要调控作用。     

大鼠骨髓间充质干细胞向多巴胺样神经细胞分化

目的探索大鼠骨髓间充质干细胞向多巴胺能样细胞分化。方法全骨髓培养法分离大鼠骨髓间充质干细胞;体外培养至第3代,用碱性成纤维细胞生长因子,抗坏血酸和表皮生长因子诱导分化;免疫荧光法鉴定胞质中的多巴胺神经元相关蛋白的表达;RT-PCR鉴定多巴胺神经元相关基因的表达;ELISA法检测上清及胞质中的多巴胺。结果诱导后,免疫荧光法检测到诱导后的细胞表达多巴胺神经元相关蛋白:酪氨酸羟化酶、多巴胺转运蛋白和神经核蛋白;RT-PCR检测到诱导后的细胞表达多巴胺神经细胞相关基因TH、AADC;ELISA法检测到诱导后的上清及胞质中有多巴胺分泌。结论间充质干细胞具有向多巴胺能样细胞分化的能力。     

细胞传代对骨髓间充质干细胞向神经干细胞分化的影响

BACKGROUND:It is unclear whether serial cell passage in vitro influences the differentiation of bone marrow mesenchymal stem cells into neural stem cells. OBJECTIVE:To investigate the effect of cell passage on the differentiation of bone marrow mesenchymal stem cells into neural stem cells. METHODS:Rat bone marrow mesenchymal stem cells were isolated and cultured by the whole bone marrow adherence method. Bone marrow mesenchymal stem cells at passages 3, 6, 9, 12 were incubated in serum-free medium. After culture for 7 and 14 days, cell biological characterization was observed and differenitaiton ability into neural stem cells was observed by detecting Nestin expression in cells using flow cytometry. Then, the cells were further induced to differentiate and cell multipotential differentiation capacity was detected by measurement of nerve enolase and glial acidic protein expression. RESULTS AND CONCLUSION:Under induction, bone marrow mesenchymal stem cells at different passages were all differentiated into Nestin-positive neural stem cells. However, there was a significant difference in differentiation proportion of cells at different passages (P < 0.05). Strongest differentiation ability was found in the passage 6 cells, with the Nestin expression up to (93.7±2.3)% at 7 days of induction and (96.2±1.8)% at 14 days of induction. The proportion of differentiated cells at passages 6 and 9 was signfiicantly higher than that at passages 3 and 12. Moreover, adherent cells were positive for nerve enolase and glial acidic protein. All these findings indicate that the differentiation of bone marrow mesenchymal stem cells into neural stem cells is correlated with cell passage. Cells at lower or higher passages are both detrimental to cell differentiation.     

骨髓间充质干细胞向功能性神经元的横向分化

背景：骨髓间充质干细胞定向分化为神经干细胞并探讨提高分化效率的方法,具有重要的理论与实际应用意义。 目的：建立以不同诱导方法横向分化大鼠骨髓间充质干细胞为功能神经元的方法。 方法：分离、纯化得到骨髓间充质干细胞,流式细胞仪检测骨髓间充质干细胞表面标志物。将骨髓间充质干细胞分为神经营养因子诱导组、化学诱导组和对照组,骨髓间充质干细胞分别加入脑源性神经营养因子和碱性成纤维细胞生长因子、二甲亚砜和丁香茴醚、PBS进行诱导。 结果与结论：神经营养因子诱导组和化学诱导组诱导后的细胞均表达神经元特异性烯醇化酶和微管相关蛋白2,且2组细胞的表达量接近(P > 0.05),而对照组未发现神经元特异性烯醇化酶和微管相关蛋白2阳性表达。膜片钳系统检测发现神经营养因子诱导组诱导后的细胞具有神经细胞特征性的动作电位和兴奋性突触后电流,而化学诱导组和对照组均未发现动作电位和兴奋性突触后电流。提示脑源性神经营养因子联合碱性成纤维细胞生长因子是一种诱导骨髓间充质干细胞横向分化为功能神经元的可靠方法。     

瘀胆血清诱导骨髓间充质干细胞向肝细胞的分化

BACKGROUND: Under certain conditions, bone marrow mesenchymal stem cells can be differentiated into hepatocytes, which are an important source of liver cells. Moreover, multiple factors can be involved in this induced differentiation process.OBJECTIVE: To investigate the inducible effect of cholestatic serum on the differentiation of bone marrow mesenchymal stem cells into hepatocytes.METHODS: Cholestatic animal model was prepared in rats to extract cholestatic serum. Bone marrow mesenchymal stem cells isolated from rats were divided into three groups and cultured in serum-free hepatocyte medium, serum-free hepatocyte medium plus cholestatic serum, serum-free hepatocyte medium plus normal serum, respectively.RESULTS AND CONCLUSION: The positive expression of alpha fetoprotein and keratin 18 and mass concentration of albumin were significantly higher in the serum-free hepatocyte medium plus cholestatic serum group than the other two groups (P < 0.05). These findings indicate that cholestatic serum has a certain inducible role in the differentiation of bone marrow mesenchymal stem cells into hepatocytes.  中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程