持续低氧增强人骨髓间充质干细胞体外增殖

目的探讨不同方式低氧对人骨髓间充质干细胞(hMSCs)增殖的影响。方法采用血球计数板计数法和流式细胞术分别观察了间歇性低氧(3%O2、10%O2)和持续性低氧(3%O2、10%O2、100μmol/LCoCl2、200μmol/LCoCl2)对hMSCs数量以及增殖指数的影响。结果间歇性低氧对hMSCs数量和增殖指数无明显影响;持续性低氧各组hM SCs数量和增殖指数均增加(P<0.05)。结论持续性低氧可促进体外培养的hMSCs增殖,说明持续性低氧作为体外的一种可控制因素,可调节hMSCs的增殖,对于hMSCs的临床应用具有一定的意义。     

骨髓间质干细胞研究进展

全能干细胞和多能干细胞具有高度自我更新能力和多向分化潜能 ,是组织工程及细胞和基因治疗中重要的靶细胞。胚胎干细胞是从早期胚胎中分离的 ,具有向机体各种组织细胞分化的潜能 ,但其自身的免疫原性以及取材困难 ,限制了它在临床上的应用。近年来研究发现 ,除了胚胎干细胞外 ,机体内还存在一些多能干细胞 ,它们具有一定的自我更新和分化能力 ,如来源于脑室管膜的神经干细胞可分化为神经元和神经胶质细胞[1] ;骨髓中的造血干细胞可分化为红细胞、粒细胞、巨噬细胞等各种血细胞。而骨髓间质干细胞作为非造血组织干细胞[2 ] ,除了参与构成支…     

Xenotransplantation of long-term-cultured swine bone marrow-derived mesenchymal stem cells

Swine-derived MSCs were efficiently isolated and extensively expanded using a low fetal serum content growth medium to which selected growth factors were added. After > or =96 cell population doublings (PDs), MSCs were devoid of cytogenetic abnormalities. In vitro chondrogenic and osteogenic differentiation capacity was preserved after 80 PDs. To test therapeutic efficacy, 1 x 10(6) 80-PD MSCs were injected directly into the peri-infarct zone of hearts of immunodeficient (non-obese diabetic/severe combined immunodeficient) mice at the time of acute myocardial infarction. Engrafted MSCs survived in the infarcted hearts for at least 4 weeks. Echocardiography at 2 and 4 weeks postinfarction revealed a significant preservation of the left ventricular ejection fractions of infarct hearts receiving MSCs compared with infarct hearts receiving saline. Peri-infarct zone capillarity was better preserved in MSC-treated hearts than other infarct groups of hearts, but infarct size was comparable in all groups. Only rare engrafted MSCs expressed cardiac-specific or endothelial cell-specific markers. Hence, 80-PD MSCs retained the capacity to promote functional improvement in the infarcted heart despite minimal differentiation of MSCs into cardiomyocytes or endothelial cells. These data suggest that the beneficial effects of MSC transplantation most likely result from the trophic effects of MSC-released substances on native cardiac and vascular cells. The capacity to massively expand MSC lines without loss of therapeutic efficacy may prove to be useful in the clinical setting where "off the shelf" MSCs may be required for interventions in patients with acute coronary syndromes.     

Functional neuronal differentiation of bone marrow-derived mesenchymal stem cells

Recent results have shown the ability of bone marrow cells to migrate in the brain and to acquire neuronal or glial characteristics. In vitro, bone marrow-derived MSCs can be induced by chemical compounds to express markers of these lineages. In an effort to set up a mouse model of such differentiation, we addressed the neuronal potentiality of mouse MSCs (mMSCs) that we recently purified. These cells expressed nestin, a specific marker of neural progenitors. Under differentiating conditions, mMSCs display a distinct neuronal shape and express neuronal markers NF-L (neurofilament-light, or neurofilament 70 kDa) and class III beta-tubulin. Moreover, differentiated mMSCs acquire neuron-like functions characterized by a cytosolic calcium rise in response to various specific neuronal activators. Finally, we further demonstrated for the first time that clonal mMSCs and their progeny are competent to differentiate along the neuronal pathway, demonstrating that these bone marrow-derived stem cells share characteristics of widely multipotent stem cells unrestricted to mesenchymal differentiation pathways.     

骨髓和脂肪来源间充质干细胞的免疫调节作用

背景：脂肪来源的间充质干细胞是否具有和骨髓来源间充质干细胞类似的免疫调节作用? 目的：观察骨髓来源和脂肪来源间充质干细胞的免疫学特征。 方法：分离骨髓和脂肪来源的间充质干细胞,分别检测它们对T细胞周期、活化、抑制和增殖的作用情况。 结果与结论：骨髓来源和脂肪来源的间充质干细胞同样具有抑制T细胞增殖的能力,在有丝分裂原刺激和混合淋巴细胞反应的T细胞增殖中这种作用都是具有剂量依赖性的,在1︰2时有极强的抑制作用,但是在1︰100时这种作用基本消失,在共培养时骨髓来源和脂肪来源的间充质干细胞都可以使更多的T细胞被抑制在G0/G1期,同时也可以抑制T细胞的早期活化,但是上述作用脂肪来源的间充质干细胞均较骨髓来源间充质干细胞弱,且脂肪来源的间充质干细胞并不具有抑制T细胞凋亡的作用。     

骨髓间充质干细胞的迁移及其相关力/化学因素调控

骨髓间充质干细胞(mesenchymal stem cells,MSCs)是一类具有自我更新和多向分化潜能的多能干细胞,在损伤组织的修复和再生中起着重要作用。MSCs从骨髓中动员、进入外周血循环向损伤组织位点定向迁移是其行使损伤组织修复功能的关键环节之一。近年来研究证实,多种力学、化学因素在MSCs向损伤组织位点定向迁移过程中起着重要的调节作用。综述MSCs通过外周血循环向损伤组织位点移动过程中相关力学、化学因素对其迁移行为的影响及其可能的分子机理,以期深入认识理化因素及其耦合对MSCs迁移行为的影响特征,为体外调控MSCs的高效迁移从而更好地应用于临床发挥其组织修复功能提供理论指导。     

Optimized lentiviral transduction of mouse bone marrow-derived mesenchymal stem cells

Mesenchymal stem cells (MSCs) have attracted much attention as potential platforms for transgene delivery and cell-based therapy for human disease. MSCs have the capability to self-renew and retain multipotency after extensive expansion in vitro, making them attractive targets for ex vivo modification and autologous transplantation. Viral vectors, including lentiviral vectors, provide an efficient means for transgene delivery into human MSCs. In contrast, mouse MSCs have proven more difficult to transduce with lentiviral vectors than their human counterparts, and because many studies use mouse models of human disease, an improved method of transduction would facilitate studies using ex vivo-modified mouse MSCs. We have worked toward improving the production of human immunodeficiency virus type 1 (HIV-1)-based lentiviral vectors and optimizing transduction conditions for mouse MSCs using lentivirus vectors pseudotyped with the vesicular stomatitis virus G glycoprotein (VSV-G), the ecotropic murine leukemia virus envelope glycoprotein (MLV-E), and the glycoproteins derived from the Armstrong and WE strains of lymphocytic choriomeningitis virus (LCMV-Arm, LCMV-WE). Mouse MSCs were readily transduced following overnight incubation using a multiplicity of infection of at least 40. Alternatively, mouse MSCs in suspension were readily transduced after a 1-h exposure to lentiviral pseudotypes immediately following trypsin treatment or retrieval from storage in liquid nitrogen. LCMV-WE pseudotypes resulted in efficient transduction of mouse MSCs with less toxicity than VSV-G pseudotypes. In conclusion, our improved production and transduction conditions for lentiviral vectors resulted in efficient transduction of mouse MSCs, and these improvements should facilitate the application of such cells in the context of mouse models of human disease.     

骨髓间充质干细胞诱导分化为神经细胞的表型变化

为了研究大鼠骨髓间充质干细胞(MSCs)诱导分化为神经细胞的表型特征,利用贴壁培养法获得骨髓MSCs。化学诱导剂二甲基亚砜(DMSO)和β-巯基乙醇(BME)联合诱导MSCs。免疫组织化学染色检测神经元特异性标志物MAP2、NSE和NF的表达,以及胶质细胞标志物GFAP的表达。硫堇-伊红染色检测细胞内Nissl体。结果表明,DMSO和BME联合诱导MSCs后48h,80%以上的细胞变为神经元样形态,胞体发出数个突起,有的似轴突,突起交织成网。免疫组化结果表明,诱导后细胞表达神经元特异性标志物MAP2、NSE和NF,其诱导率分别为88.6%,87.1%和85.8%。神经干细胞的特征性生物学标记nestin的诱导率在诱导后2h和10h较高,分别为48%和71.4%,而在诱导后48h仅为0.06%。诱导后细胞不表达GFAP。Nissl染色结果表明,诱导后细胞胞质中含有Nissl体。本研究结果证明DMSO和BME联合诱导MSCs可获得具有神经元表型特征的MSCs源性神经细胞。     

Bioreactor expansion of human adult bone marrow-derived mesenchymal stem cells

Supplementation of mesenchymal stem cells (MSCs) during hematopoietic stem cell (HSC) transplantation alleviates complications such as graft-versus-host disease, leading to a speedy recovery of hematopoiesis. To meet this clinical demand, a fast MSC expansion method is required. In the present study, we examined the feasibility of using a rotary bioreactor system to expand MSCs from isolated bone marrow mononuclear cells. The cells were cultured in a rotary bioreactor with Myelocult medium containing a combination of supplementary factors, including stem cell factor and interleukin-3 and -6. After 8 days of culture, total cell numbers, Stro-1(+)CD44(+)CD34(-) MSCs, and CD34(+)CD44(+)Stro-1(-) HSCs were increased 9-, 29-, and 8-fold, respectively. Colony-forming efficiency-fibroblast per day of the bioreactor-treated cells was 1.44-fold higher than that of the cells without bioreactor treatment. The bioreactor-expanded MSCs showed expression of primitive MSC markers endoglin (SH2) and vimentin, whereas markers associated with lineage differentiation, including osteocalcin (osteogenesis), type II collagen (chondrogenesis), and C/EBP-alpha (CCAAT/enhancer-binding protein-alpha) (adipogenesis), were not detected. Upon induction, the bioreactor-expanded MSCs were able to differentiate into osteoblasts, chondrocytes, and adipocytes. We conclude that the rotary bioreactor with the modified Myelocult medium reported in this study may be used to rapidly expand MSCs.     

CM-DIL和DAPI标记的骨髓间充质干细胞

背景：在有关“细胞移植”的实验研究中,细胞标记技术被广泛应用。CM-DIL与DAPI是细胞标记实验中常用的荧光染料,目前两者的对比研究报道较少。 目的：从体外实验与体内实验两方面,探讨两种荧光染料CM-DIL与DAPI在标记大鼠骨髓间充质干细胞方面的差异。 方法：用贴壁培养法获取、培养、扩增大鼠骨髓间充质干细胞,分别用CM-DIL与DAPI进行标记,锥虫蓝计数检测骨髓间充质干细胞的活力;MTS法检测骨髓间充质干细胞的增殖能力并绘制增殖曲线;倒置相差荧光显微镜下动态观察标记后1,2,3代骨髓间充质干细胞的荧光衰减情况。结扎SD大鼠冠状动脉前降支致心肌梗死。1周后于心肌梗死边缘处注射CM-DIL与DAPI标记的细胞,细胞移植后3 d取材观察骨髓间充质干细胞的分布情况。 结果与结论：体外实验中,CM-DIL与DAPI标记的骨髓间充质干细胞两者的早期增殖能力均低于对照组;两种染料标记后的第1代细胞的荧光阳性率均为100%,但DAPI标记后的第3代细胞的荧光强度明显减弱。体内实验中,CM-DIL组与DAPI组心肌组织冰冻与石蜡切片均检测到集中分布的荧光;CM-DIL组冰冻切片红色荧光比DAPI组的蓝色荧光边界清晰并且背景低;CM-DIL组还可以通过含细胞核染色的封片剂封片排除荧光假阳性。可见,CM-DIL染料比DAPI更适合对骨髓间充质干细胞进行体内示踪。     

芒果苷对缺氧损伤骨髓间充质干细胞凋亡的保护

背景：缺氧性死亡限制了细胞移植和组织再生中细胞的应用。 目的：观察芒果苷对氯化钴作用下骨髓间充质干细胞缺氧损伤性凋亡的保护作用。 方法：体外培养大鼠骨髓间充质干细胞,应用氯化钴建立细胞缺氧模型,以芒果苷对缺氧损伤下的骨髓间充质干细胞进行保护,通过MTT实验观察芒果苷对大鼠骨髓间充质干细胞缺氧损伤的保护作用;采用流式细胞仪检测芒果苷对大鼠骨髓间充质干细胞缺氧保护的细胞凋亡及线粒体膜电位检测结果。 结果与结论：氯化钴能显著抑制大鼠骨髓间充质干细胞的生长,并且呈明显的剂量依赖关系。氯化钴200 μmol/L处理细胞12 h,诱导细胞凋亡率为(42.49±3.96)%;处理细胞24 h,诱导细胞凋亡率为(46.37±4.49)%,随着芒果苷浓度的增加,大鼠骨髓间充质干细胞缺氧损伤的凋亡率逐步减少(P < 0.01),芒果苷对大鼠骨髓间充质干细胞缺氧损伤具有保护作用,且呈浓度依赖性。结果提示,氯化钴缺氧模型能成功诱导大鼠骨髓间充质干细胞凋亡,具有剂量准确可控、无特殊设备要求、易操作等优点;芒果苷能有效抑制缺氧损伤时骨髓间充质干细胞的凋亡,对细胞具有保护作用。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;组织工程全文链接：     

牙周膜干细胞诱导骨髓间充质干细胞的牙向分化

目的 探讨牙周膜干细胞(PDLSC)诱导骨髓间充质干细胞(BMMSC)牙向分化的机制,为联合应用PDLSC和BMMSC再生牙周复合体提供实验依据.方法应用Transwell(R)小室法间接联合培养小型猪PDLSC和BMMSC,根据二者混合比例随机分为3组.A组:P∶M=10∶1共培养组;B组:P∶M=1∶1共培养;C组:P:M=1:10共培养,单独PDLSC和BMMSC培养组分别为阳性和阴性对照组.培养14 d,应用免疫荧光染色和实时定量PCR(qRT-PCR)分别检测scleraxis、osteocalcin(OCN)、osterix(OSX)、细胞外基质磷酸糖蛋白(MEPE)蛋白和mRNA表达情况,以判定PDLSC诱导BMMSC成牙的最佳配比比例.结果 免疫荧光染色和qRT-PCR结果均显示scleraxis、OCN和OSX相对mRNA表达水平在A、B、C组间没有统计学差异(P>0.05),但相对MEPE mRNA表达水平在A组却明显高于B组和C组(P＜0.01).结论 联合培养可促进BMMSC获得不同程度的PDLSC特性,且少量的PDLSC同样可以促进BMMSC获得牙源性干细胞特性.     

肾上腺髓质素对缺氧培养骨髓间充质干细胞表达凋亡相关蛋白的影响

背景：肾上腺髓质素基因转染能增强骨髓间充质干细胞在缺血、缺氧环境下的抗凋亡能力,但其机制尚未完全明确。 目的：观察肾上腺髓质素对骨髓间充质干细胞缺血、缺氧时Bax、Bcl-2和Caspase-3等凋亡相关调节蛋白表达的影响。 方法：贴壁法分离、培养、纯化SD大鼠骨髓间充质干细胞,缺氧、无血清培养0,3,6,9,12 h后用Western blot测定Bax、Bcl-2、Caspase-3蛋白的表达以确定最佳缺氧时间。采用缺氧6 h为时间点,根据缺氧、无血清培养前是否进行肾上腺髓质素预处理分为对照组(未加入肾上腺髓质素)及肾上腺髓质素不同质量浓度组(1,10,100 μg/L),然后采用Western blot测定Bax、Bcl-2、Caspase-3蛋白的表达。 结果与结论：①无血清培养条件下缺氧0,3,6,9,12 h后骨髓间充质干细胞 Bax、Bcl-2表达均增加(P < 0.05),缺氧6 h时Bax/Bcl-2比值、caspase-3蛋白达到最小(P < 0.05)。②缺氧6 h时,与1,10 μg/L肾上腺髓质素组相比,100 μg/L肾上腺髓质素组表达Bax蛋白、Caspase-3蛋白最低,Bax/Bcl-2比值最低,而表达Bcl-2蛋白最高(P < 0.05)。结果表明肾上腺髓质素能降低无血清、缺氧条件下骨髓间充质干细胞Bax/Bcl-2比值、Caspase-3蛋白表达,该效应存在剂量依赖性。  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     

心肌细胞培养上清诱导骨髓间充质干细胞的分化

背景：前期研究发现,心肌细胞培养上清具有诱导骨髓间充质干细胞分化为心肌样细胞的能力,这可能与培养上清内的某种细胞因子或几种细胞因子有关。 目的：分析大鼠心肌细胞培养上清诱导骨髓间充质干细胞分化为心肌样细胞是否与心肌细胞培养上清内细胞因子含量不同有关。 方法：采用全骨髓贴壁培养法分离骨髓间充质干细胞并在体外培养纯化,酶消化法分离心肌细胞,分别以 1×10⁸ L^-1的细胞浓度培养72 h后收集上清。用酶联免疫吸附试验技术检测心肌细胞和骨髓间充质干细胞培养上清内的肝细胞生长因子、胰岛素样生长因子1、血小板源生长因子、干细胞因子、成纤维细胞生长因子和血管内皮生长因子的水平。 结果与结论：心肌细胞培养上清组内的胰岛素样生长因子1、血小板源生长因子和成纤维细胞生长因子水平明显高于骨髓间充质干细胞培养上清组(P < 0.01),提示心肌细胞培养上清内的胰岛素样生长因子1、血小板源生长因子和成纤维细胞生长因子可能与诱导骨髓间充质干细胞分化为心肌样细胞有关,其中主要的细胞因子是胰岛素样生长因子1。     

芒果苷对缺氧损伤骨髓间充质干细胞的保护作用

背景：研究表明骨髓间充质干细胞移植在临床治疗方面具有广阔的应用前景。然而,移植细胞的死亡限制了组织再生,寻找新的抗自由基和保护骨髓间充质干细胞的药物有着重要意义。 目的：研究芒果苷对体外培养大鼠骨髓间充质干细胞缺氧损伤的保护作用。 方法：采用氯化钴(CoCl2)建立体外培养的大鼠骨髓间充质干细胞缺氧损伤模型。将细胞分为正常对照组、氯化钴缺氧损伤组、氯化钴加芒果苷20,40,80,160 µmol/L组。缺氧损伤12,24 h检测各组骨髓间充质干细胞培养上清液中超氧化物歧化酶、丙二醛、过氧化氢酶水平。缺氧损伤3,6,12,24 h检测各组骨髓间充质干细胞内活性氧变化。 结果与结论：芒果苷能明显提高缺氧损伤的骨髓间充质干细胞的存活率,提高细胞内超氧化物歧化酶、过氧化氢酶活性,降低细胞内丙二醛、活性氧水平,有效保护缺氧损伤下的骨髓间充质干细胞。芒果苷具有较强的抗氧化能力及缺氧保护作用,可明显减轻骨髓间充质干细胞的氧化应激损伤。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;组织工程全文链接：     

骨髓基质干细胞在软骨组织工程中的应用

骨关节炎等损坏关节软骨的疾病严重影响人们的正常生活。骨髓基质干细胞具有较强的自我更新能力和多向分化潜能，在特定的诱导条件下分化为软骨细胞，为组织工程软骨修复软骨缺损带来希望。就骨髓基质干细胞分离、诱导分化为软骨细胞的方法、载体材料及目前存在的问题加以综述。