人间充质干细胞抑制肝癌细胞增殖的作用及其基因表达谱分析

干细胞移植治疗肿瘤具有重要的临床价值．应用人间充质干细胞条件培养液作用H7402肝癌细胞,拟探讨间充质干细胞对肿瘤细胞的抑制作用,为今后应用人间充质干细胞进行肿瘤细胞治疗奠定理论基础．应用胎儿真皮来源的 Z3 间充质干细胞和胎儿骨髓来源的 BMMS-03 间充质干细胞的条件培养液作用于H7402肝癌细胞,采用软琼脂克隆形成实验、流式细胞仪技术、基因芯片技术和免疫印迹技术观察 H7402 细胞的克隆形成、增殖和基因表达谱变化．结果显示,H7402 细胞在间充质干细胞条件培养液作用下,克隆形成和增殖受到了明显抑制;基因芯片检测结果显示,H7402 细胞在间充质干细胞条件培养液作用下有 23 个基因上调表达,17 个基因下调表达,这些差异表达的基因与细胞的转录调控、新陈代谢、信号转导、细胞周期、应激反应和细胞粘附等功能相关．本实验结果表明,人间充质干细胞对 H7402 肝癌细胞的克隆形成和增殖具有抑制作用,并有多种基因的表达发生改变,这些基因表达的改变可能参与了对上述肿瘤细胞的抑制．     

间充质干细胞的生物学特性及心血管修复潜能的研究进展

间充质干细胞存在于成体组织中,来源于骨髓、脂肪组织等,在体外易分离和培养,是具有塑料粘附性的一群非均质细胞。它们具有分化的潜能,在适当的条件下可分化为心肌和血管。临床前期研究显示,在心脏损伤模型中移植间充质干细胞有利于心肌修复和心血管形成。其作用机制与间充质干细胞再生和旁分泌能力密切相关。在临床应用中,间充质干细胞具有免疫抑制作用,也可用于异体移植。总之,虽然间充质干细胞的研究尚有许多问题亟待解决,但是它在心脏疾病的细胞治疗和组织工程中已显示出广阔的前景。     

骨髓间充质干细胞的免疫学研究进展

间充质干细胞（mesenchymal stem cells,MSCs）是骨髓中除造血干细胞以外的另一种成体干细胞,广泛分布于动物体内骨髓、肝脏、脂肪等多种组织中。MSCS具有强大的自我更新能力和多向分化潜能,是移植领域应用前景广阔的再生来源细胞;同时,MSCs是一种重要的免疫调节细胞,MSCs在炎症细胞因子刺激后对免疫系统表现出很强的抑制作用,所以MSCs有望应用于减少免疫排斥,延长移植物存活时间,治疗相关免疫失调症,如自身免疫疾病等方面。本文主要对间充质干细胞与免疫系统相互作用的研究做相关介绍。     

间充质干细胞释放 Dkk-1 抑制乳腺癌细胞 Wnt/β-catenin 途径的实验研究

研究表明,间充质干细胞具有向肿瘤细胞定向迁移并且抑制肿瘤细胞的特性,然而其分子机理目前尚不清楚.为了探讨间充质干细胞抑制肿瘤细胞作用的分子机制,应用BMMS-03人间充质干细胞的条件培养液作用于MCF-7乳腺癌细胞,通过软琼脂克隆形成实验、MTT实验、免疫印迹和免疫荧光染色等技术观察细胞克隆形成、增殖和基因表达的变化.结果显示:在BMMS-03细胞条件培养液作用下,MCF-7细胞的克隆形成和增殖受到了明显的抑制,β-catenin及其下游靶蛋白c-Myc、Bcl-2、PCNA和survivin的表达被明显下调,MCF-7细胞浆和细胞核内β-catenin的表达被明显抑制.BMMS-03细胞中Dkk-1的表达水平与MCF-7细胞相比较高.利用抗Dkk-1的抗体中和BMMS-03细胞条件培养液中的Dkk-1后,可明显拮抗BMMS-03细胞条件培养液对MCF-7细胞中β-catenin及c-Myc表达的抑制作用,基因转染使MCF-7细胞过表达Dkk-1后,MCF-7细胞的β-catenin及c-Myc的表达明显下调.同样经基因转染使BMMS-03细胞过表达Dkk-1后,其条件培养液可进一步下调MCF-7细胞β-catenin及c-Myc的表达.上述结果表明,间充质干细胞BMMS-03对乳腺癌MCF-7细胞的恶性表型具有明显抑制作用,其分子机制与间充质干细胞释放Dkk-1抑制乳腺癌细胞Wnt/β-catenin信号途径有关.     

人脐带间充质干细胞食蟹猴连续静脉输注后免疫毒性与免疫调节作用研究

该文旨在研究人脐带间充质干细胞在食蟹猴体内的免疫毒性与免疫调节特性。连续14天给予食蟹猴不同剂量(2.0×10~6个·kg~(-1)和2.0×10~7个·kg~(-1))的人脐带间充质干细胞静脉滴注,检测食蟹猴血清IgG浓度、抗人脐带间充质干细胞抗体、淋巴细胞活化增殖和T细胞亚群的变化,以及胸腺和脾脏组织学变化。结果显示,连续14天静脉给予人脐带间充质干细胞对食蟹猴血清IgG浓度无影响,不刺激动物产生抗人脐带间充质干细胞抗体。人脐带间充质干细胞显著抑制食蟹猴淋巴细胞的活化增殖,降低CD3~(+)T细胞比例,刺激Treg细胞的增殖分化。组织学检查发现,部分动物出现与给药相关的胸腺皮质萎缩和脾脏淋巴生发中心增多增大。该研究得出,人脐带间充质干细胞的免疫毒性极低,静脉输注后不引起食蟹猴体内免疫排斥等异常反应,提示其在临床上异体应用的安全性。     

间充质干细胞诱导分化为胰岛β细胞的研究进展

间充质干细胞是一类具有多向分化潜能的成体干细胞,在体内外不仅可以被诱导分化为中胚层细胞,而且可以分化为内胚层和神经外胚层细胞。间充质干细胞易分离,体外可大量扩增,异体移植不引起免疫排斥反应,在细胞治疗和组织工程中具有广阔的应用前景。经过适当诱导,间充质干细胞可能成为胰岛β细胞的来源之一。就间充质干细胞的生物学性状和优势,以及诱导分化为胰岛β细胞的技术方法和发展趋势进行了综述。     

人脐带间充质干细胞条件培养基联合白藜芦醇对人滋养层细胞的作用

目的:探讨人脐带间充质干细胞条件培养基联合白藜芦醇对人绒毛膜外滋养层细胞凋亡的影响。方法:通过CCK8细胞活力检测试剂盒测定白藜芦醇及其与人脐带间充质干细胞条件培养基共同处理人绒毛膜外滋养层细胞HTR8后对细胞增殖及活性的影响;细胞迁移试验检测白藜芦醇和人脐带间充质干细胞条件培养基对细胞迁移能力的影响;显微镜观察细胞形态,并用流式细胞仪检测细胞凋亡率的变化;Western blot检测白藜芦醇和人脐带间充质干细胞条件培养基对细胞凋亡相关蛋白Bax、Bcl-2以及迁移相关蛋白MMP-9表达的影响。结果:白藜芦醇能够抑制HTR8细胞增殖,抑制细胞迁移及MMP-9蛋白的表达,改变Bax和Bcl-2蛋白表达诱导细胞凋亡的作用。而人脐带间充质干细胞条件培养基能够逆转白藜芦醇对细胞的抑制作用。结论:人脐带间充质干细胞条件培养基能够通过调控Bax、Bcl-2、MMP-9的蛋白表达逆转白藜芦醇对人绒毛膜外滋养层细胞的抑制作用。人脐带间充质干细胞条件培养基可作为潜在的治疗人绒毛膜外滋养层细胞功能障碍的临床手段,孕妇需要小心使用白藜芦醇。     

脐带间充质干细胞辅助治疗糖皮质激素耐药的慢性移植物抗宿主病5例并文献复习

目的:探讨脐带间充质干细胞输注治疗糖皮质激素耐药的慢性移植物抗宿主病的疗效和安全性。方法:5例糖皮质激素耐药的慢性移植物抗宿主病患者在原有免疫抑制剂治疗基础上联合脐带间充质干细胞治疗,2~4次为1个疗程,每次间隔1周。对患者进行定期随访观察其治疗效果、移植相关死亡、输注相关不良事件和复发率。结果:5例患者接受脐带间充质干细胞输注后2例获得完全缓解(CR)、2例获得部分缓解(PR),1例患者死亡。2例CR患者分别在脐带间充质干细胞治疗368、452d后停用免疫抑制剂,随访1~1.5年慢性移植物抗宿主病无复发;2例PR患者在脐带间充质干细胞治疗84、96d后开始进入免疫抑制剂减量阶段,目前病情仍稳定并存活。1例患者死于原发病无复发性肺部严重感染。治疗过程中及治疗后未观察到与治疗有关的副作用。新鲜制备脐带间充质干细胞的细胞活力(92%~95%)高于液氮冻存37℃水浴复苏细胞活力(72%~76%)。结论:脐带间充质干细胞辅助治疗可以改善糖皮质激素耐药的慢性移植物抗宿主病的临床症状且不增加恶性血液病复发率,新鲜制备间充质干细胞活性高于液氮冻存复苏细胞。     

间充质干细胞免疫抑制作用及其在移植免疫中应用的研究进展

间充质干细胞(MSC)是一类具有自我更新、增殖和多向分化潜能的干细胞,具有向内、中、外3个胚层包括肌腱、韧带、肝细胞、心肌细胞和骨髓基质细胞等分化、发育的潜能。有研究表明,MSC具有较低的免疫原性,它可以通过与免疫细胞直接接触和分泌细胞因子等机制发挥免疫调节作用,从而成为移植免疫领域的研究热点,本文就MSC的生物学特性、免疫抑制作用及在移植免疫中的应用做一综述。     

3种间充质干细胞成软骨分化潜能比较

目的:比较骨髓间充质干细胞、脂肪间充质干细胞、滑膜间充质干细胞3种间充质干细胞的成软骨分化潜能,为软骨组织工程中种子细胞的选择提供实验依据。方法:采用贴壁法分别分离提取兔骨髓间充质干细胞、脂肪间充质干细胞、滑膜间充质干细胞3种间充质干细胞,并进行传代培养,绘制3种间充质干细胞的生长曲线并比较其倍增时间。将3种间充质干细胞成软骨诱导14 d后,行甲苯胺蓝染色及II型胶原免疫组化染色以观测3种细胞成软骨分化能力。结果:脂肪间充质干细胞的倍增时间短于骨髓间充质干细胞,滑膜间充质干细胞的倍增时间最短;3种细胞成软骨诱导14 d后均产生糖胺聚糖和II型胶原,且组与组之间II型胶原表达水平的差异有统计学意义,骨髓间充质干细胞组高于脂肪间充质干细胞组(P0.01),滑膜间充质干细胞组高于骨髓间充质干细胞组(P0.01)。结论:在一定的培养条件下,3种间充质干细胞均有一定的成软骨细胞分化潜能,滑膜间充质干细胞最快的增殖速度及最强的成软骨分化潜能。     

The antiproliferative effect of mesenchymal stem cells is a fundamental property shared by all stromal cells

Although it has been widely demonstrated that human mesenchymal stem cells exert potent immunosuppressive effects, there is little information as to whether more mature mesenchymal stromal cells (SC) share the same property. Accordingly, we set out to test the ability of SC from different human tissues to inhibit the proliferation of PBMC following polyclonal stimuli. Chondrocytes, as well as fibroblasts from synovial joints, lung, and skin, were used as a source of SC. Irrespective of their differentiation potential and/or content of progenitor cells, SC from all tissues exhibited antiproliferative functions. This was in marked contrast to parenchymal cells. Although SC did not interfere with early T lymphocyte activation, they arrested stimulated T cells in the G(0)/G(1) phase of the cell cycle and rescued them from apoptosis. In addition, IFN-gamma and TNF-alpha production were reduced. We observed that the inhibitory effect is ultimately mediated by soluble factors, the production of which requires SC to be licensed in an inflammatory environment by cell contact. We conclude that the immunosuppressive effect of mesenchymal cells is not confined to multipotent stem cells, but is a fundamental characteristic of all stroma. Our data suggest that SC, appropriately licensed, regulate T cell homeostasis.     

Regulation of stemness and stem cell niche of mesenchymal stem cells: Implications in tumorigenesis and metastasis

Human mesenchymal stem cells (MSCs) derived from adult tissues have been considered a candidate cell type for cell‐based tissue engineering and regenerative medicine. These multipotent cells have the ability to differentiate along several mesenchymal lineages and possibly along non‐mesenchymal lineages. MSCs possess considerable immunosuppressive properties that can influence the surrounding tissue positively during regeneration, but perhaps negatively towards the pathogenesis of cancer and metastasis. The balance between the naïve stem state and differentiation is highly dependent on the stem cell niche. Identification of stem cell niche components has helped to elucidate the mechanisms of stem cell maintenance and differentiation. Ultimately, the fate of stem cells is dictated by their microenvironment. In this review, we describe the identification and characterization of bone marrow‐derived MSCs, the properties of the bone marrow stem cell niche, and the possibility and likelihood of MSC involvement in cancer progression and metastasis. J. Cell. Physiol. 222: 268–277, 2010. © 2009 Wiley‐Liss, Inc.     

人脐带间充质干细胞移植治疗脊髓损伤的研究进展

脊髓损伤（SCI）由于复杂病理生理和神经修复再生困难,至今仍旧是难以攻克的医学难题,而干细胞因其神经再生和神经保护特性被认为是治疗SCI最有希望的方法。其中人脐带间充质干细胞（HUC-MSCs）近年培养分化方法不断改进、神经修复机制初步阐明,联合移植等综合治疗方案也不断实践,使HUC-MSCs移植治疗效果提高。另外关于HUC-MSCs治疗SCI的临床试验逐渐开展,术后患者神经功能恢复改善且无严重并发症出现,表明干细胞移植应用于人体是安全有效的。本文就HUC-MSCs治疗SCI的研究状况及进展进行综述。     

Allogeneic mesenchymal stem cells: agents of immune modulation

Adult mesenchymal stem cells possess a remarkably diverse array of immunosuppressive characteristics. The capacity to suppress the regular processes of allogeneic rejection, have allowed the use of tissue mismatched cells as therapeutic approaches in regenerative medicine and as agents of immune deviation. This review describes recent advances in understanding the mechanistic basis of mesenchymal stromal or stem cells (MSC) interaction with innate immunity. Particular emphasis is placed on the effect of Toll-like receptor signalling on MSC and a hypothesis that innate immune signals induce a 'licensing switch' in MSC is put forward. The mechanisms underlying MSC suppression of T cell responses and induction of regulatory populations are surveyed. Conflicting data regarding the influence of MSC on B cell function are outlined and discussed. Finally the limits to MSC mediated immune modulation are discussed with reference to the future clinical application of novel cell therapies.     

Transplantation-potential-related biological properties of decidua basalis mesenchymal stem cells from maternal human term placenta

Human placental decidua basalis originates from the maternal side of the placenta and has been described as a source of mesenchymal stem cells (MSCs). However, for its application in tissue regeneration and repair, the transplantation-potential-related biological properties of decidua-basalis-derived mesenchymal stem cells (DBMSCs) remain to be elucidated. We obtained DBMSCs through enzymatic digestion and density gradient centrifugation and confirmed their capacity to differentiate into cell types of the mesodermal lineage, such as osteoblasts, adipocytes and chondroblasts. Karyotype analysis showed that the isolated DBMSCs maintained chromosomal stability after long-term culture in vitro. Growth kinetics and ultrastructural observation revealed a high level of DBMSC proliferative activity. In addition, DBMSCs showed immunosuppressive properties by suppressing both mitogen- and alloantigen-induced peripheral lymphocyte proliferation. All of these properties suggest that DBMSCs, which are abundant and easily accessible, are a novel potential source of seed cells for cell transplantation treatments.     

骨髓间充质干细胞移植治疗终末期肝病:现状与前景

应用骨髓间充质干细胞及其分化来源的肝细胞移植来改善肝功能、桥接肝脏器官移植的治疗方法具有许多优势。目前已有实验研究和小规模临床实践运用这一方法,但是其临床疗效尚需评估,同时治疗机制也需要进一步探讨。该文就目前骨髓间充质干细胞分化为肝细胞及应用的临床和基础研究现状进行综述,对存在的问题及发展前景进行探讨。     

IFN-γ-primed human bone marrow mesenchymal stem cells induce tumor cell apoptosis in vitro via tumor necrosis factor-related apoptosis-inducing ligand

Human mesenchymal stem cells hold promise as gene therapy vectors for delivery of various genes to solid tumors for either therapeutic or tumor-tracing purposes. However, whether Mesenchymal stem cells support or inhibit tumor growth remains unknown. Herein, we first observed that mesenchymal stem cells primed with IFN-γ selectively induced the death of tumor cell lines, but not normal cells. We further identified that IFN-γ-primed mesenchymal stem cells expressed tumor necrosis factor-related apoptosis-inducing ligand. Tumor-suppressive effect of IFN-γ-primed mesenchymal stem cells could be blocked by activity neutralization or expression reduction of tumor necrosis factor-related apoptosis-inducing ligand. Moreover, mesenchymal stem cells mediated apoptosis of tumor cells by activating caspase-3 in such cells, via a mechanism involving tumor necrosis factor-related apoptosis-inducing ligand. However, when IFN-γ-primed or non-primed mesenchymal stem cells were co-injected into nude mice along with H460 cells, tumor growth was much faster than that of the group receiving only tumor cells (p<0.01) because of the promoting vascularization effect of mesenchymal stem cells, although IFN-γ-primed mesenchymal stem cells also exerted a certain degree of tumor-suppressive effect compared with non-primed cells (2.79±0.9 g versus 2.03±0.6 g). Collectively, our findings show that IFN-γ-primed human mesenchymal stem cells could induce cancer cell apoptosis via TRAIL-mediated pathway. In addition, our data afford a novel explanation of the opposing effects of hMSCs presence on tumor growth in vitro and in vivo. Thus, more attention needs to be paid when seeking to exploit mesenchymal stem cells as a therapeutic option under the condition of malignant tumor.     

Differences and similarities between mesenchymal stem cell and endothelial progenitor cell immunoregulatory properties against T cells

Bone-marrow-derived mesenchymal stem cells and endothelial progenitor cells have some interesting biological properties that make them unique for cell therapy of degenerative and cardiovascular disorders. Although both cell populations have been already studied and used for their regenerative potentials, recently their special immunoregulatory features have brought much more attention. Mesenchymal stem cells and endothelial progenitor cells have both proangiogenic functions and have been shown to suppress the immune response, particularly T cell proliferation, activation, and cytokine production. This makes them suitable choices for allogeneic stem cell transplantation. Nevertheless, these two cells do not have equal immunoregulatory activities. Many elements including their extraction sources, age/passage, expression of different markers, secretion of bioactive mediators, and some others could change the efficiency of their immunosuppressive function. However, to our knowledge, no publication has yet compared mesenchymal stem cells and endothelial progenitor cells for their immunological interaction with T cells. This review aims to specifically compare the immunoregulatory effect of these two populations including their Tcell suppression, deactivation, cytokine production, and regulatory T cells induction capacities. Moreover, it evaluates the implications of the tumor necrosis factor alpha-tumor necrosis factor receptor 2 axis as an emerging immune checkpoint signaling pathway controlling most of their immunological properties.     

Mesenchymal stem cells induce dermal fibroblast responses to injury

Although bone marrow-derived mesenchymal stem cells have been shown to promote repair when applied to cutaneous wounds, the mechanism for this response remains to be determined. The aim of this study was to determine the effects of paracrine signaling from mesenchymal stem cells on dermal fibroblast responses to injury including proliferation, migration and expression of genes important in wound repair. Dermal fibroblasts were co-cultured with bone marrow-derived mesenchymal stem cells grown in inserts, which allowed for paracrine interactions without direct cell contact. In this co-culture model, bone marrow-derived mesenchymal stem cells regulate dermal fibroblast proliferation, migration and gene expression. When co-cultured with mesenchymal stem cells, dermal fibroblasts show increased proliferation and accelerated migration in a scratch assay. A chemotaxis assay also demonstrated that dermal fibroblasts migrate towards bone marrow-derived mesenchymal stem cells. A PCR array was used to analyze the effect of mesenchymal stem cells on dermal fibroblast gene expression. In response to mesenchymal stem cells, dermal fibroblasts up-regulate integrin alpha 7 expression and down-regulate expression of ICAM1, VCAM1 and MMP11. These observations suggest that mesenchymal stem cells may provide an important early signal for dermal fibroblast responses to cutaneous injury.     

Human mesenchymal stem cells inhibit the differentiation and effector functions of monocytes

Although monocytes represent an essential part of the host defence system, their accumulation and prolonged stimulation could be detrimental and may aggravate chronic inflammatory diseases. The present study has explored the less-understood immunomodulatory effects of mesenchymal stem cells on monocyte functions. Isolated purified human monocytes were co-cultured with human umbilical cord-derived mesenchymal stem cells under appropriate culture conditions to assess monocytes’ vital functions. Based on the surface marker analysis, mesenchymal stem cells halted monocyte differentiation into dendritic cells and macrophages and reduced their phagocytosis functions, which rendered an inability to stimulate T-cell proliferation. The present study confers that mesenchymal stem cells exerted potent immunosuppressive activity on monocyte functions such as differentiation, phagocytosis and Ag presentation; hence, they promise a potential therapeutic role in down-regulating the unwanted monocyte-mediated immune responses in the context of chronic inflammatory diseases.