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1.
Influence of culture conditions and extracellular matrix alignment on human mesenchymal stem cells invasion into decellularized engineered tissues 下载免费PDF全文
Nathan K. Weidenhamer Dusty L. Moore Fluvio L. Lobo Nathaniel T. Klair Robert T. Tranquillo 《Journal of tissue engineering and regenerative medicine》2015,9(5):605-618
The variables that influence the in vitro recellularization potential of decellularized engineered tissues, such as cell culture conditions and scaffold alignment, have yet to be explored. The goal of this work was to explore the influence of insulin and ascorbic acid and extracellular matrix (ECM) alignment on the recellularization of decellularized engineered tissue by human mesenchymal stem cells (hMSCs). Aligned and non‐aligned tissues were created by specifying the geometry and associated mechanical constraints to fibroblast‐mediated fibrin gel contraction and remodelling using circular and C‐shaped moulds. Decellularized tissues (matrices) of the same alignment were created by decellularization with detergents. Ascorbic acid promoted the invasion of hMSCs into the matrices due to a stimulated increase in motility and proliferation. Invasion correlated with hyaluronic acid secretion, α‐smooth muscle actin expression and decreased matrix thickness. Furthermore, hMSCs invasion into aligned and non‐aligned matrices was not different, although there was a difference in cell orientation. Finally, we show that hMSCs on the matrix surface appear to differentiate toward a smooth muscle cell or myofibroblast phenotype with ascorbic acid treatment. These results inform the strategy of recellularizing decellularized engineered tissue with hMSCs. © 2015 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd. 相似文献
2.
背景:如何运用无血清培养体系大规模扩增处于未分化状态的脂肪间充质干细胞,并使其保持“干性”是脂肪间充质干细胞临床应用转化中急待解决的难题。目的:建立含细胞外基质的脂肪间充质干细胞体外培养系统,验证其扩增细胞的高效性、有效性及安全性。方法:在无血清培养条件下,将体外分离得到的脂肪间充质干细胞分别接种在包被细胞外基质的培养板和传统二维塑料培养板上。经过体外扩增后,比较2种条件下细胞数量、细胞表面标记物表达、细胞衰老状况以及体外多向分化能力(诱导成脂、成骨和成软骨)的差异,考察脂肪间充质干细胞在含细胞外基质的培养条件下扩增后的临床安全性。结果与结论:脂肪间充质干细胞扩增到第5代时,包被细胞外基质培养板的细胞产量已经是传统二维塑料培养板的10倍以上,流式细胞检测表明,在含细胞外基质条件下扩增的脂肪间充质干细胞仍保持了干细胞表面特定标记物的表达。细胞衰老检测结果显示,使用包被细胞外基质的培养板扩增脂肪间充质干细胞至第15代时,细胞仍几乎无老化现象,而使用二维塑料培养板扩增的细胞在第5代时已出现明显老化,传代后细胞增殖能力明显下降。体外多向诱导分化实验显示,脂肪间充质干细胞在含细胞外基质条件下扩增至第15代时仍具有成脂、成骨和成软骨的分化功能,并且与第5代时没有明显差异,同时显著优于传统培养条件下的第5代脂肪间充质干细胞。染色体核型分析及小鼠成瘤性试验结果表明,脂肪间充质干细胞在含细胞外基质条件下扩增后仍具备临床应用的安全性。以上结果证实,含细胞外基质的无血清培养系统可以更高效且安全地扩增出具有临床应用潜能的脂肪间充质干细胞。 相似文献
3.
Ezequiel J. Molina Jon Palma Dipin Gupta Denise Torres John P. Gaughan Steven Houser Mahender Macha 《Journal of tissue engineering and regenerative medicine》2009,3(2):85-91
Changes in ventricular extracellular matrix (ECM) composition of pressure overload hypertrophy determine clinical outcomes. The effects of mesenchymal stem cell (MSC) transplantation upon determinants of ECM composition in pressure overload hypertrophy have not been studied. Sprague–Dawley rats underwent aortic banding and were followed by echocardiography. After an absolute decrease in fractional shortening of 25% from baseline, 1 × 106 MSC (n = 28) or PBS (n = 20) was randomly injected intracoronarily. LV protein analysis, including matrix metalloproteinases (MMP‐2, MMP‐3, MMP‐6, MMP‐9) and tissue inhibitors of metalloproteinases (TIMP‐1, TIMP‐2, TIMP‐3), was performed after sacrifice on postoperative day 7, 14, 21 or 28. Left ventricular levels of MMP‐3, MMP‐6, MMP‐9, TIMP‐1 and TIMP‐3 were demonstrated to be decreased in the MSC group compared with controls after 28 days. Expression of MMP‐2 and TIMP‐2 remained relatively stable in both groups. Successful MSCs delivery was confirmed by histological analysis and visualization of labelled MSCs. In this model of pressure overload hypertrophy, intracoronary delivery of MSCs during heart failure was associated with specific changes in determinants of ECM composition. LV reverse remodeling was associated with decreased ventricular levels of MMP‐3, MMP‐6, MMP‐9, TIMP‐1 and TIMP‐3, which were upregulated in the control group as heart failure progressed. These effects were most significant at 28 days following injection. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
4.
Influence of in vitro biomimicked stem cell ‘niche’ for regulation of proliferation and differentiation of human bone marrow‐derived mesenchymal stem cells to myocardial phenotypes: serum starvation without aid of chemical agents and prevention of spontaneous stem cell transformation enhanced by the matrix environment 下载免费PDF全文
Niche appears important for preventing the spontaneous differentiation or senescence that cells undergo during in vitro expansion. In the present study, it was revealed that human bone marrow‐derived mesenchymal stem cells (hBM‐MSCs) undergo senescence‐related differentiation into the myocardial lineage in vitro without any induction treatment. This phenomenon occurred over the whole population of MCSs, much different from conventional differentiation with limited frequency of occurrence, and was accompanied by a change of morphology into large, flat cells with impeded proliferation, which are the representative indications of MSC senescence. By culturing MSCs under several culture conditions, it was determined that induction treatment with 5‐azacytidine was not associated with the phenomenon, but the serum‐starvation condition, under which proliferation is severely hampered, caused senescence progression and upregulation of cardiac markers. Nevertheless, MSCs gradually developed a myocardial phenotype under normal culture conditions over a prolonged culture period and heterogeneous populations were formed. In perspectives of clinical applications, this must be prevented for fair and consistent outcomes. Hence, the biomimetic 'niche' was constituted for hBM‐MSCs by cultivating on a conventionally available extracellular matrix (ECM). Consequently, cells on ECM regained a spindle‐shape morphology, increased in proliferation rate by two‐fold and showed decreased expression of cardiac markers at both the mRNA and protein levels. In conclusion, the outcome indicates that progression of MSC senescence may occur via myocardial differentiation during in vitro polystyrene culture, and this can be overcome by employing appropriate ECM culture techniques. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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背景:微骨折术方法简单,操作方便,是治疗关节软骨缺损有效的方法之一,但仍然存在再生软骨为纤维软骨、再生软骨退化等问题。现在学者们主要致力于使用各种方法改良微骨折修复软骨缺损的效果。 目的:探索微骨折处理软骨缺损区域后植入自体骨髓间充质干细胞外基质支架治疗猪膝关节软骨缺损的疗效。 方法:分离并原代培养猪骨髓间充质干细胞,收集其分泌的细胞外基质膜,采用交联、冻干技术将收集的基质膜制备成三维多孔支架。选取小型成年猪,制备双膝股骨髁、股骨滑车部全层软骨缺损模型,深2 mm,直径6 mm;采用自体左右对照模式,右膝作为对照组,使用单纯微骨折治疗软骨缺损,左膝作为实验组,采用微骨折处理软骨缺损区域后,植入预先制备的支架。术后6个月使用番红固绿染色、Masson 染色等评价软骨再生情况,使用Wakitani评分整体评估再生软骨,并测定再生组织糖胺聚糖、DNA含量。 结果与结论:术后6个月,实验组股骨滑车和股骨髁处均可见软骨修复,表面光滑,对照组股骨滑车修复组织表面较平整,股骨髁未见明显修复。实验组股骨滑车和股骨髁再生软骨经番红固绿染色、Masson染色均显示软骨层基质含量丰富,软骨下骨骨小梁密集,对照组软骨层染色不明显,软骨下骨修复欠佳。实验组Wakitani评分、糖胺聚糖含量高于对照组,DNA含量低于对照组(P<0.05)。结果可见微骨折结合自体骨髓间充质干细胞外基质支架修复软骨效果良好,股骨滑车和股骨髁治疗效果无显著差异。 相似文献
6.
Liver extracellular matrix promotes BM‐MSCs hepatic differentiation and reversal of liver fibrosis through activation of integrin pathway 下载免费PDF全文
Ruiping Cheng Hailang Luo Yongjie Zhang Yan Jin 《Journal of tissue engineering and regenerative medicine》2017,11(10):2685-2698
In cell‐based therapies for liver injuries, the clinical outcomes are closely related to the surrounding microenvironment of the transplanted bone marrow mesenchymal stem cells (BM‐MSCs). However, whether liver‐specific ECM (L‐ECM), as one of major microenvironment signals, could regulate the therapeutic effect of BM‐MSCs through changing their biological characteristics is unclear. This study aimed to investigate the hepatogenicity and underlying mechanism of L‐ECM as well as its potential regulative role in the MSC‐based liver recovery. L‐ECM was prepared by homogenization of decellularized whole porcine liver. After three‐dimensional culture with or without the presence of L‐ECM, BM‐MSCs expressed hepatocyte‐specific genes and proteins in an L‐ECM concentration‐dependent manner. Further analysis showed that L‐ECM could activate specific types of integrins (ITGs) as well as their downstream signalling pathways. When the cell/ECM interaction was enhanced by incorporating BM‐MSCs with Mn2+, ITGs were activated and the hepatogenic capacity of L‐ECM was improved. The regeneration of rat livers from either acute or chronic fibrosis could also be accelerated after transplantation of Mn2+‐treated BM‐MSCs. L‐ECM therefore promotes hepatic differentiation of BM‐MSCs via the ITG pathway and plays a therapeutically beneficial role for stem cell‐based liver regeneration. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
7.
Rebekka Wehner Christina Taubert Tanja Mende Christian Gaebler Ana Valeria Gouveia de Andrade Martin Bornhäuser Carsten Werner Torsten Tonn Knut Schäkel Michael Bachmann Marc Schmitz 《Journal of tissue engineering and regenerative medicine》2013,7(11):921-924
Mesenchymal stromal cells (MSCs) have emerged as promising candidates for regenerative therapies, including tissue engineering. Recently it has been reported that engineered extracellular matrix (ECM) components support the differentiation of MSCs into osteocytes and chondrocytes, indicating that ECM components may represent attractive carriers for MSC transplants to repair damaged tissues. However, little is known about the impact of engineered ECM components on the immunosuppressive properties of MSCs, which may essentially contribute to the prevention of allogeneic MSC transplant rejection. In the present study, we explored the potential of fibronectin, fibrillar collagen I, tropocollagen and collagen I/heparin to influence the immunosuppressive capacities of MSCs. We found that these ECM components do not modulate the capability of MSCs to inhibit the proliferation of anti‐CD3/anti‐CD28 antibody‐stimulated CD4+ and CD8+ T cells and of lymphocytes in a mixed lymphocyte reaction. In addition, the potential of MSCs to impair the production of immunostimulatory IL‐12 and to improve the release of immunosuppressive IL‐10 by 6‐sulpho LacNAc+ (slan) dendritic cells (DCs), representing a pro‐inflammatory subset of human blood DCs, was not altered by the ECM components. Furthermore, ECM components do not influence the ability of MSCs to inhibit the slanDC‐induced proliferation of CD4+ T cells. In conclusion, the used engineered ECMs maintain important immunosuppressive properties of MSCs, which support their suitablility as carriers for MSC transplants in tissue engineering. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
8.
Sabanting Hednella Syva Kamaruzaman Ampon Helen Lasimbang Simat Siti Fatimah 《Journal of tissue engineering and regenerative medicine》2017,11(2):311-320
Human amnion mesenchymal stem cells (HAMCs) show great differentiation and proliferation potential and also other remarkable features that could serve as an outstanding alternative source of stem cells in regenerative medicine. Recent reports have demonstrated various kinds of effective artificial niche that mimic the microenvironment of different types of stem cell to maintain and control their fate and function. The components of the stem cell microenvironment consist mainly of soluble and insoluble factors responsible for regulating stem cell differentiation and self‐renewal. Extensive studies have been made on regulating HAMCs differentiation into specific phenotypes; however, the understanding of relevant factors in directing stem cell fate decisions in HAMCs remain underexplored. In this review, we have therefore identified soluble and insoluble factors, including mechanical stimuli and cues from the other supporting cells that are involved in directing HAMCs fate decisions. In order to strengthen the significance of understanding on the relevant factors involved in stem cell fate decisions, recent technologies developed to specifically mimic the microenvironments of specific cell lineages are also reviewed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
V. Hintze A. Miron S. Möller M. Schnabelrauch S. Heinemann H. Worch D. Scharnweber 《Journal of tissue engineering and regenerative medicine》2014,8(4):314-324
In this study we investigated the potential of artificial extracellular matrix (aECM) coatings containing collagen II and two types of glycosaminoglycan (GAGs) with different degrees of sulphation to promote human bone formation in biomedical applications. To this end their impact on growth and osteogenic differentiation of human mesenchymal stem cells (hMSCs) was assessed. The cell proliferation was found to be significantly retarded in the first 14 days of culture on surfaces coated with collagen II and GAGs (coll‐II/GAG) as compared to tissue culture polystyrol (TCPS) and those coated with collagen II. At later time points it only tended to be retarded on coll‐II/sHya3.1. Heat‐inactivation of the serum significantly reduced cell numbers on collagen II and coll‐II/sHya3.1. Alkaline phosphatase (ALP) activity and calcium deposition, on the other hand, were higher for coatings containing sHya3.1 and were not significantly changed by heat‐inactivation of the serum. Expression levels of the bone matrix proteins bone sialoprotein (BSP‐II) and osteopontin (OP) were also increased on aECM coatings as compared to TCPS, which further validated the differentiation of hMSCs towards the osteogenic lineage. These observations reveal that aECM coatings, in particular those containing sHya3.1, are suitable to promote the osteogenic differentiation of hMSCs. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.
Application of marrow mesenchymal stem cell‐derived extracellular matrix in peripheral nerve tissue engineering 下载免费PDF全文
Jing Huang Hongkui Wang Xiaosong Gu Jianhui Gu 《Journal of tissue engineering and regenerative medicine》2017,11(8):2250-2260
To advance molecular and cellular therapy into the clinic for peripheral nerve injury, modification of neural scaffolds with the extracellular matrix (ECM) of peripheral nerves has been established as a promising alternative to direct inclusion of support cells and/or growth factors within a neural scaffold, while cell‐derived ECM proves to be superior to tissue‐derived ECM in the modification of neural scaffolds. Based on the fact that bone marrow mesenchymal stem cells (BMSCs), just like Schwann cells, are adopted as support cells within a neural scaffold, in this study we used BMSCs as parent cells to generate ECM for application in peripheral nerve tissue engineering. A chitosan nerve guidance conduit (NGC) and silk fibroin filamentous fillers were respectively prepared for co‐culture with purified BMSCs, followed by decellularization to stimulate ECM deposition. The ECM‐modified NGC and lumen fillers were then assembled into a chitosan–silk fibroin‐based, BMSC‐derived, ECM‐modified neural scaffold, which was implanted into rats to bridge a 10 mm‐long sciatic nerve gap. Histological and functional assessments after implantation showed that regenerative outcomes achieved by our engineered neural scaffold were better than those achieved by a plain chitosan–silk fibroin scaffold, and suggested the benefits of BMSC‐derived ECM for peripheral nerve repair. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
11.
Matrix‐directed differentiation of human adipose‐derived mesenchymal stem cells to dermal‐like fibroblasts that produce extracellular matrix 下载免费PDF全文
Unnikrishnan Sivan K. Jayakumar Lissy K. Krishnan 《Journal of tissue engineering and regenerative medicine》2016,10(10):E546-E558
Commercially available skin substitutes lack essential non‐immune cells for adequate tissue regeneration of non‐healing wounds. A tissue‐engineered, patient‐specific, dermal substitute could be an attractive option for regenerating chronic wounds, for which adipose‐derived mesenchymal stem cells (ADMSCs) could become an autologous source. However, ADMSCs are multipotent in nature and may differentiate into adipocytes, osteocytes and chondrocytes in vitro, and may develop into undesirable tissues upon transplantation. Therefore, ADMSCs committed to the fibroblast lineage could be a better option for in vitro or in vivo skin tissue engineering. The objective of this study was to standardize in vitro culture conditions for ADMSCs differentiation into dermal‐like fibroblasts which can synthesize extracellular matrix (ECM) proteins. Biomimetic matrix composite, deposited on tissue culture polystyrene (TCPS), and differentiation medium (DM), supplemented with fibroblast‐conditioned medium and growth factors, were used as a fibroblast‐specific niche (FSN) for cell culture. For controls, ADMSCs were cultured on bare TCPS with either DM or basal medium (BM). Culture of ADMSCs on FSN upregulated the expression of differentiation markers such as fibroblast‐specific protein‐1 (FSP‐1) and a panel of ECM molecules specific to the dermis, such as fibrillin‐1, collagen I, collagen IV and elastin. Immunostaining showed the deposition of dermal‐specific ECM, which was significantly higher in FSN compared to control. Fibroblasts derived from ADMSCs can synthesize elastin, which is an added advantage for successful skin tissue engineering as compared to fibroblasts from skin biopsy. To obtain rapid differentiation of ADMSCs to dermal‐like fibroblasts for regenerative medicine, a matrix‐directed differentiation strategy may be employed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
12.
背景:骨髓间充质干细胞可被定向诱导分化为神经样细胞,理论上骨髓间充质干细胞可作为种子细胞应用于周围神经组织工程。目的:用2种细胞因子联合诱导骨髓间充质干细胞分化为神经样细胞,进一步探讨其在周围神经损伤方面的应用。方法:从Wistar大鼠胫骨和股骨提取骨髓间充质干细胞,采用差速贴壁法进行培养和纯化,联合应用碱性成纤维细胞生长因子和表皮生长因子对细胞进行诱导,观察细胞形态变化,并用免疫组织化学方法检测骨髓间充质干细胞中神经元特异性标志物的表达;并研究终止诱导后骨髓间充质干细胞的形态及免疫组织化学方面的变化。 结果与结论:骨髓间充质干细胞经诱导后呈典型神经细胞样改变,有两个或多个突起,突起之间相互连接成网状,可见细胞核及核仁,免疫组化检测神经元特异性烯醇化酶、神经丝蛋白及突触素蛋白表达阳性。撤除诱导条件后大部分细胞逐渐恢复原来的成纤维细胞样形态,上述3种蛋白的表达量明显下降。表明应用神经营养因子可诱导骨髓间充质干细胞分化为神经样细胞,但其形态及组织学变化仅能维持一段较短的时间。 相似文献
13.
背景:在组织工程领域,关于骨髓间充质干细胞定向诱导分化的研究越来越多,但是细胞培养基中不同成分会对骨髓间充质干细胞的体外增殖分化产生影响。目的:针对培养基中不同因子对骨髓间充质干细胞定向诱导分化的作用加以综述。方法:第一作者应用计算机检索1998年1月至2012年4月Pubmed数据库及万方数据库。检索英文关键词为“bone marrow mesenchymal stromal cells, cell culture medium, differentiation”,中文关键词为“骨髓间充质干细胞,细胞培养,定向诱导分化”,纳入有关不同因子对骨髓间充质干细胞向成骨细胞、软骨细胞和脂肪细胞定向诱导分化作用的文献,排除重复研究。结果与结论:计算机初检共得到184篇文献,根据纳入排除标准,对其中30篇文献进行综述。大体说来,骨髓间充质干细胞向成骨分化的主要因子有地塞米松、转化生长因子、维生素C、维生素D3、β-甘油磷酸钠及乙烯雌酚等;向软骨分化的主要因子有地塞米松、转化生长因子、维生素C、胰岛素样生长因子及成纤维细胞生长因子等;向脂肪细胞转化的主要因子有地塞米松、3-异丁基-1-甲基黄嘌呤、胰岛素和消炎痛等,但是其中一些因子的作用机制及不良反应还不明确,需要进一步的研究与验证。同时,骨髓间充质干细胞在骨髓中的含量较低,不同的分离方法会导致不同的分离率,因此如何选取一种分离率高的分离方法仍有待研究。 相似文献
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Marta S. Carvalho Joo C. Silva Joaquim M.S. Cabral Cludia L. da Silva Deepak Vashishth 《Journal of tissue engineering and regenerative medicine》2019,13(9):1544-1558
Cell‐derived extracellular matrix (ECM) consists of a complex assembly of fibrillary proteins, matrix macromolecules, and associated growth factors that mimic the composition and organization of native ECM micro‐environment. Therefore, cultured cell‐derived ECM has been used as a scaffold for tissue engineering settings to create a biomimetic micro‐environment, providing physical, chemical, and mechanical cues to cells, and support cell adhesion, proliferation, migration, and differentiation. Here, we present a new strategy to produce different combinations of decellularized cultured cell‐derived ECM (dECM) obtained from different cultured cell types, namely, mesenchymal stem/stromal cells (MSCs) and human umbilical vein endothelial cells (HUVECs), as well as the coculture of MSC:HUVEC and investigate the effects of its various compositions on cell metabolic activity, osteogenic differentiation, and angiogenic properties of human bone marrow (BM)‐derived MSCs, vital features for adult bone tissue regeneration and repair. Our findings demonstrate that dECM presented higher cell metabolic activity compared with tissue culture polystyrene. More importantly, we show that MSC:HUVEC ECM enhanced the osteogenic and angiogenic potential of BM MSCs, as assessed by in vitro assays. Interestingly, MSC:HUVEC (1:3) ECM demonstrated the best angiogenic response of MSCs in the conditions tested. To the best of our knowledge, this is the first study that demonstrates that dECM derived from a coculture of MSC:HUVEC impacts the osteogenic and angiogenic capabilities of BM MSCs, suggesting the potential use of MSC:HUVEC ECM as a therapeutic product to improve clinical outcomes in bone regeneration. 相似文献
16.
骨髓间充质干细胞体外诱导分化为神经样细胞的机制 总被引:3,自引:3,他引:3
目的探索骨髓间充质干细胞 (MSCs)在体外诱导分化为神经样细胞的机制。方法分离培养大鼠MSCs ,用二甲基亚砜 (DSMO)和丁羟茴醚 (BHA)诱导分化 ,检测诱导分化前、预诱导 2 4h、诱导分化后 6h、2 4h和 48h神经细胞和神经干细胞的特异性标记蛋白的表达。结果诱导分化后 ,大部分MSCs变成双极、多极和锥形 ,并相互交织成网络结构 ,巢蛋白 (Nestin)在诱导分化前不表达 ,在诱导分化后 6h达到最高 ,2 4h和 48h逐渐降低。神经元特异性核蛋白 (NeuN )在诱导分化前不表达 ,在诱导分化后 6h出现表达 ,2 4h和 48h表达增强。结论MSCs经体外诱导先分化为神经干细胞 ,然后分化为神经元样细胞。 相似文献
17.
Corneal keratocyte transition to mesenchymal stem cell phenotype and reversal using serum‐free medium supplemented with fibroblast growth factor‐2, transforming growth factor‐β3 and retinoic acid 下载免费PDF全文
Laura E. Sidney Andrew Hopkinson 《Journal of tissue engineering and regenerative medicine》2018,12(1):e203-e215
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背景:骨髓间充质干细胞的多向分化能力在骨代谢疾病中发挥重要作用,受激素、细胞因子等多种因素调节。目前骨髓间充质干细胞骨向分化的表观遗传学调控机制尚不明确,组蛋白去乙酰化酶与骨质疏松的关系尚需进一步探讨。 目的:建立雌激素缺乏骨质疏松小鼠的实验动物模型,检测骨髓间充质干细胞组蛋白去乙酰化酶1,3,4 mRNA表达水平,探索卵巢切除小鼠骨组织形成障碍的表观遗传学机制。 方法:昆明种小鼠30只随机等分为模型组和假手术组。小鼠适应性喂养7 d后,模型组小鼠切除双侧卵巢,造成雌激素缺乏骨质疏松实验动物模型,假手术组小鼠仅切除等量脂肪组织。 结果与结论:模型组小鼠股骨骨小梁稀疏或断裂,骨小梁宽度变窄,骨小梁间距变宽,骨小梁占视野面积降低。与假手术组相比,模型组小鼠骨髓间充质干细胞中组蛋白去乙酰化酶3 mRNA表达水平显著降低,组蛋白去乙酰化酶1,4表达水平变化差异无显著性意义。提示雌激素缺乏导致骨髓间充质干细胞去乙酰化状态改变可能是骨形成障碍的重要原因之一。 相似文献
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目的研究人骨髓间充质干细胞(mesenchymal stem cells,MSCs)向神经细胞分化的可能性。方法利用Per-coil梯度分离及贴壁筛选法分离培养和扩增MSCs;利用bFGF、化学诱导剂DMSO和BHA联合诱导MSCs向神经元转化,观察分化过程中细胞形态的变化,利用免疫细胞化学和RT-PCR方法检测神经元特异性标志物的表达情况。结果经Perecoll梯度分离及贴壁筛选法获得了纯度较高的人MSCs,诱导分化后的细胞呈现双极、多极和锥形的典型神经元细胞的形态,并且分别从mRNA和蛋白水平上证明诱导分化后的细胞表达神经元标记物NSE和NF,不表达神经胶质细胞标记物GFAP。结论人MSCs可以在体外诱导分化为神经元样细胞,这种潜能使其有可能成为神经系统疾病细胞移植治疗的种子细胞。 相似文献
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背景:脐血造血干细胞移植价值日益突出,造血干细胞体外扩增已成为干细胞领域的研究热点。目的:复习相关文献,对脐血间充质干细胞支持造血作用研究现状与应用前景进行综述。方法:应用计算机检索CNKI和PubMed数据库中2001至2012年关于脐血间充质干细胞造血支持作用的文章,中文检索词为"脐血间充质干细胞,造血干细胞,CD34+细胞,体外扩增",英文检索词为"Hematopoietic stem cell expansion,CD34+cell expansion,Umbilical cord blood mesenchymal stem cells"。最终选择35篇文章进入结果分析。结果与结论:脐血间充质干细胞支持造血作用的多种作用机制,包括分泌多种具有造血支持作用的细胞因子,表达与造血细胞相互作用的黏附分子等。因此,体外扩增造血干细胞,临床联合移植间充质干细胞和造血干细胞,提高造血重建的能力,具有广阔的研究前景。 相似文献