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The rate of migration of bone marrow hematopoietic stem cells (HSC) was studied by two methods in experiments on 54 dogs. In the first case the dogs were irradiated subtotally with an absolutely lethal dose of 550 R, with both knee joints screened. When the screened areas were inactivated by irradiation in a dose of 2000 R 7 days after the first irradiation, the survival rate of the animals was 12.5%, but in the case of inactivation after 14 days, all the dogs survived. In the second case both knee joints were irradiated initially in a dose of 2000 R. After subsequent subtotal irradiation in a dose of 550 R, with the previously irradiated regions screened, all the animals died if the second irradiation was given after 7 days, whereas 20% of the animals survived if the time between irradiations was increased to 31 days. It is concluded that migration of HSC in dogs is much lower in degree than in mice.Laboratory of Experimental Cytology and Histology, Central Research Institute of Radiology and Roentgenology, Ministry of Health of the USSR, Leningrad. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 12, pp. 714–716, December, 1979.  相似文献   

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背景:目前,大量文献报道了诱导多能性干细胞系的建立,但大规模体外诱导分化造血祖细胞的研究还缺乏深入的探讨。 目的:建立诱导多能性干细胞体外定向诱导形成造血祖细胞的方法。 方法:采用慢病毒感染的方法将含有Oct4、Sox2、Nanog和Lin28全能性基因的慢病毒颗粒转导人皮肤成纤维细胞,获得了诱导多能性干细胞;在诱导分化体系中添加了Y-27632,克服干细胞扩增中的凋亡现象;运用OP9细胞产生的条件培养液建立诱导多能性干细胞体外定向分化形成造血祖细胞的分化体系。 结果与结论:①前3代细胞克隆传代时,诱导多能性干细胞发生凋亡的现象很多,很难大规模扩增培养。培养基中添加阻断ROCK活化的抑制剂,能够明显抑制胚胎干细胞的凋亡。②诱导多能性干细胞在OP9细胞条件培养液作用下,经过体外诱导分化,形成CD34+造血祖细胞。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:  相似文献   

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背景:如何提高胚胎干细胞诱导效率、促进胚胎干细胞源造血干细胞体外增殖成为目前急需解决的课题。目的:以外源性Wnt3a作为诱导剂,激活培养中的小鼠胚胎干细胞Wnt/β-catenin信号通路,观察该通路的激活是否促进胚胎干细胞向造血祖细胞的定向分化。方法:用外源性wnt3a(100 µg/L)持续作用ES-E14TG2a小鼠胚胎干细胞21 d,通过细胞免疫荧光及蛋白免疫印迹检测细胞内β-catenin蛋白含量,QRT-PCR检测Wnt下游靶标基因的表达量来确定经典Wnt/β-catenin信号通路是否被激活,然后采用单层贴壁培养法诱导其向造血干细胞分化,流式细胞仪检测造血发育相关表面标志CD34+/Sca-1+,同时以QRT-PCR法检测造血相关基因的表达情况。结果与结论:ES-E14TG2a小鼠胚胎干细胞经wnt3a(100 µg/L)连续培养21 d后发现β-catenin蛋白在细胞内积累;Wnt信号通路的下游靶标基因Pitx2、Frizzled、Sox17、Oct4的表达量均出现不同程度的增加,可见经典Wnt/β-catenin信号通路有被激活;单层贴壁培养法诱导其向造血干细胞分化的过程中检测到CD34+/Sca-1+细胞含量在14 d时占总细胞量高达20.2%,而对照组的仅占11.9%。造血相关基因骨形态发生蛋白4、FLK2及CD34的表达量均增加,而Smad5的表达则明显受到抑制。说明Wnt3a持续作用可激活Wnt/β-catenin信号通路,并促进ES-E14TG2a小鼠胚胎干细胞向造血干细胞的定向分化。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:  相似文献   

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Experiments on (CBA×C57BL)F1 mice showed that during the period of a sharp rise in the blood endogenous glucocorticoid level 30 min-6 h after burns the number of circulating colony-forming units (CFU) falls by 50–60%. At the same time migration of CFU from an area of bone marrow screened during irradiation (850 R) was inhibited. On the 3rd-4th day after burns, migration of CFU was intensified.Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 10, pp. 494–496, October, 1978.  相似文献   

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Expgenous cloning of hematopoietic stem cells of bone marrow and spleen in the femur and spleen of recipient mice showed that during hypokinesia the kinetics of the stem cell population differs in the two organs (spleen and bone marrow). The character of differentiation of the transplantation stem cells from the different sources was undisturbed in the recipients' spleen. Bone marrow stem cells, settling in the femur, changed their character of differentiation toward an increase in erythropoietic function, whereas the direction of differentiation of the splenic stem cells was unchanged.Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 4, pp. 501–503, April, 1976.  相似文献   

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背景:自体外周血造血干细胞移植因患者年龄范围宽、移植后并发症少、费用低,临床应用日益广泛.移植后造血功能的重建主要取决于输入造血干细胞的数量和质量.文章从临床实际出发,分析影响外周血造血干细胞采集的各种因素,并计算出适宜采集的血常规标准,对提高临床外周血造血干细胞采集成功率进而提高自体移植成功率有重要意义.目的:分析血...  相似文献   

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Laboratory for Control of Biosynthesis of Animal Tissues, Institute of Biophysics, Siberian Branch, Academy of Sciences of the USSR, Krasnoyarsk. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. A. Vladimirov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 11, pp. 488–489, November, 1991.  相似文献   

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背景:有效预防和治疗异基因造血干细胞移植后并发症是提高患者存活率的重要因素。 目的:分析异基因造血干细胞移植后相关并发症的发生和危险因素。 方法:应用文献检索的方法获取异基因造血干细胞移植后相关并发症研究的文献,对符合研究标准的文献进行深入的数据分析,文章选取异基因造血干细胞移植后极易发生的并发症进行分析,如肺部并发症、真菌性败血症、巨细胞病毒感染以及中枢神经系统并发症等。 结果与结论:异基因造血干细胞移植后易出现肺部并发症,而且死亡率较高,肺部并发症的发病机制可能与移植物抗宿主病和巨细胞病毒抗原血症相关。异基因造血干细胞移植后真菌性败血症病原菌以假丝酵母菌属为主,死亡率较高,应二级预防性和早期经验性抗真菌治疗。更昔洛韦、膦甲酸钠对异基因造血干细胞移植后巨细胞病毒感染的治疗有效。中枢神经系统并发症在异基因造血干细胞移植后发生率较低,但在治疗过程也不容忽视。异基因造血干细胞移植后相关并发症的发生与多种危险因素有关,在临床治疗过程中要对相关因素采取预防措施,减少并发症的发生,提高患者的存活率。  相似文献   

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目的研究衰老骨髓基质细胞对骨髓造血细胞增殖分化能力的影响,为阐述机体造血微环境衰老对造血干/祖细胞增殖的影响提供实验依据。方法全骨髓贴壁法体外培养大鼠骨髓基质细胞,分为对照组和衰老组。衰老组:常规培养基内加入30 mg/m L D-半乳糖作用48 h。CCK-8法测定BMSCs增殖;流式细胞术分析细胞周期;β-半乳糖苷酶(SA-β-Gal)染色观察衰老BMSCs百分率;Western blot检测P16、P21和P53蛋白表达。骨髓造血细胞与BMSCs共培养,集落计数检测髓系多向性造血祖细胞(CFU-Mix)增殖分化。ELISA检测BMSCs培养上清液中IL-1β、GM-CSF和SCF含量;DCFH-DA流式荧光检测BMSC活性氧簇(ROS)水平;酶学法检测BMSCs内过氧化物丙二醛(MDA)含量和总超氧化物歧化酶(SOD)活性。结果与对照组相比,D-半乳糖诱导BMSCs衰老,细胞阻滞于G0/G1期(P0.01),增殖能力显著下降,SA-β-Gal染色阳性率升高(P0.01);衰老相关蛋白P16、P21和P53表达明显上调(P0.01)。与衰老BMSCs共培养的骨髓造血细胞增殖分化能力减弱。衰老BMSCs内ROS、MDA氧化损伤指标上升,SOD抗氧化指标下降(P0.01);BMSCs培养上清液IL-1β、GM-CSF和SCF含量明显下降(P0.01)。结论衰老骨髓基质细胞抑制造血细胞增殖、分化能力,其机制可能与骨髓基质细胞氧化损伤,分泌活性因子改变有关。  相似文献   

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背景:在体外和体内关于细胞对于不同的机械牵张反应的大量研究表明,牵张能够刺激成骨。然而鲜有文献报道不同的牵张方式对于同种细胞的影响有何不同。 目的:比较不同机械牵张方式对大鼠骨髓间充质干细胞的影响。 方法:分离培养大鼠骨髓间充质干细胞,应用自行研制的牵张装置对骨髓间充质干细胞分别施加动态、静态和模拟临床的混合牵张牵张刺激,分别检测3种刺激方式下骨髓间充质干细胞的增殖能力、碱性磷酸酶活性及Runx2基因的mRNA表达,并测量细胞骨钙素的分泌情况。 结果与结论:静态牵张组与对照组相比,细胞增殖能力提高18.67%,碱性磷酸酶活性、Runx2表达及骨钙素分泌无明显差异;动态牵张组相对于对照组,细胞碱性磷酸酶活性提高60.33%, Runx2表达上升49.67%,细胞外骨钙素的分泌提高了48%,然而细胞增殖则受到了抑制;混合牵张组相对于对照组,细胞增殖能力稍有上升但无统计学差异,其对碱性磷酸酶活性、Runx2表达以及骨钙素的分泌有一定的促进作用,但没有动态牵张组明显。结果提示,静态牵张能够显著刺激骨髓间充质干细胞的增殖,而动态牵张对于刺激骨髓间充质干细胞成骨向分化作用更为明显,混合牵张方式对于细胞增殖及成骨分化均有一定的促进作用。  相似文献   

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目的:探讨血清对雪旺细胞诱导神经上皮干细胞分化的影响。方法:从新生鼠坐骨神经及臂丛神经分离纯化雪旺细胞,从孕11.5 d大鼠胚胎分离培养神经上皮干细胞,含0%、1%、5%、10%胎牛血清的培养液联合培养雪旺细胞与神经上皮干细胞,收集上清作为条件培养液诱导神经上皮干细胞分化,1周后MAP-2和GFAP细胞免疫化学染色,显微镜下观察统计神经上皮干细胞分化为神经元与星形胶质细胞的比例。结果:条件培养液促进神经上皮干细胞存活和分化,分化形成的神经元大体形态与成熟神经元相似,0%、1%、5%、10%血清条件培养液组神经元与星形胶质细胞比例分别为1.53:1、1.13:1、1.03:1、0.75:1。结论:血清影响雪旺细胞诱导神经上皮干细胞向神经元分化,血清浓度增加,神经上皮干细胞分化形成的神经元减少。  相似文献   

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Two FDA-approved agents, ferumoxides (Feridex), a suspension of superparamagnetic iron oxide (SPIO) nanoparticles and protamine sulfate, a drug used to reverse heparin anticoagulation, can be complexed and used to label cells magnetically ex vivo. Labeling stem cells with ferumoxides-protamine sulfate (FePro) complexes allows for non-invasive monitoring by MRI. However, in order for stem cell trials or therapies to be effective, this labeling technique must not inhibit the ability of cells to differentiate. In this study, we examined the effect of FePro labeling on stem cell differentiation. Viability, phenotypic expression and differential capacity of FePro labeled CD34 + hematopoietic stem cells (HSC) and mesenchymal stem cells (MSC) were compared with unlabeled control cells. Colony-forming unit (CFU) assays showed that the capacity to differentiate was equivalent for labeled and unlabeled HSC. Furthermore, labeling did not alter expression of surface phenotypic markers (CD34, CD31, CXCR4, CD20, CD3 and CD14) on HSC, as measured by flow cytometry. SDF-1-induced HSC migration and HSC differentiation to dendritic cells were also unaffected by FePro labeling. Both FePro-labeled and unlabeled MSC were cultured in chondrogenesis-inducing conditions. Alcian blue staining for proteoglycans revealed similar chondrogenic differentiation for both FePro-labeled and unlabeled cells. Furthermore, collagen X proteins, indicators of cartilage formation, were detected at similar levels in both labeled and unlabeled cell pellets. Prussian blue staining confirmed that cells in labeled pellets contained iron oxide, whereas cells in unlabeled pellets did not. It is concluded that FePro labeling does not alter the function or differentiation capacity of HSC and MSC. These data increase confidence that MRI studies of FePro-labeled HSC or MSC will provide an accurate representation of in vivo trafficking of unlabeled cells.  相似文献   

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A study of the number of stem cells in splenic colonies and of marked chromosomes in the progeny of the stem cells that recirculating colony-forming units from peripheral blood or from a focus of ectopic hematopoiesis have reduced self-support potential compared with settling (from bone marrow) colony-forming units. The powers of differentiation of the two subpopulations of stem cells were identical.Laboratory of Bone Marrow Culture and Transplantation, Central Institute of Hematology and Blood Transfusion, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 6, pp. 579–582, June, 1979.  相似文献   

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目的: 体外模拟胚胎早期AGM区造血微环境,诱导胚胎干细胞(ESCs)分化为造血干细胞(HSCs)。方法:将小鼠E14 ESCs在含BMP-4及VEGF的半固体培养基中诱导为拟胚体(EB),分别于3、6、9、12、15 d时收获EB,流式细胞术检测Flk-1+细胞含量。取Flk-1+ 细胞处于高峰期的EB细胞,在人AGM区基质细胞饲养层上进一步诱导分化,并设无饲养层对照,分别于3、6、9、12 d时收获细胞计数、流式细胞术检测Sca-1+c-kit+ 细胞含量,并分析造血细胞集落形成能力。结果:诱导E14细胞形成EB过程中添加BMP4+VEGF的因子组Flk-1+细胞在第9 d达峰值(27.53%± 2.84%),与未添加因子组(8.77%± 1.12%)比较差异显著(P<0.05)。将培养9 d的EB细胞在hAGMS3、hAGMS4饲养层上进一步诱导分化,第6 d时Sca-1+c-kit+细胞达峰值,分别为7.31%±1.21%、7.62%±1.52%,其绝对数分别扩增(2.57±0.48)倍、(2.35±0.36)倍,与无饲养层组比较显著差异(P<0.05)。该分化阶段的Sca-1+c-kit+细胞具有形成各系造血细胞集落的能力。结论:人胚早期AGM区基质细胞能促进小鼠ESCs定向分化为HSCs,为研究ESCs分化为HSCs的分子机制提供了实验模型。  相似文献   

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