生长因子诱导人脐带/胎盘间充质干细胞定向分化

近年来,间充质干细胞(mesenchymal stem cell,MSC)已成为干细胞领域的研究热点,其不仅支持造血系统,还可在特定的培养条件下向多种组织细胞分化。人脐带和胎盘来源的MSC取材容易,较骨髓间充质干细胞有更广泛的应用前景。本文就含有特定生长因子的培养基诱导人脐带MSC和人胎盘MSC定向分化的研究进展作一简要的综述。     

人滑膜间充质干细胞与人脐带间充质干细胞的生物学性状比较

该文旨在比较人滑膜间充质干细胞(human synovial mesenchymal stem cells,hSMSCs)与人脐带间充质干细胞(human umbilical cord mesenchymal stem cells,hUC-MSCs)的生物学性状.流式细胞仪鉴定hSMSCs和hUC-MSCs.比较两种间...     

脐带间充质干细胞的生物学特性及旁分泌作用的研究进展

脐带是由胚胎外中胚层和/或胚胎中胚层发育而来的组织,脐带间充质干细胞是具有自我更新、多向分化以及高度增殖潜能的多功能干细胞。研究证明,脐带间充质干细胞具有以下功能：参与炎症反应,抑制炎症因子分泌并促进免疫调节;参与受损伤组织的治疗与修复使其再生并改善特定疾病症状;抑制肿瘤增殖和迁移以及促进其凋亡等。然而目前尚未明确以上功能是间充质干细胞本身发挥作用,还是其分泌的相关因子对机体修复产生作用。主要对脐带间充质干细胞的定义、来源、生物学特性、分泌功能等方面的研究进展进行了综述,旨在更好地利用间充质干细胞修复组织,以期为脐带间充质干细胞的后续研究提供参考依据。     

人脐带间充质干细胞研究进展及应用前景

人脐带问充质干细胞（hUCMSC）是来源于发育早期中胚层和外胚层、存在于脐带沃顿胶和血管周围组织中的一类具有自我更新、增殖和多向分化潜能的干细胞。当前主要通过分离、扩增传代培养,然后超低温保存的方法提取保存hUCMSC。与其他来源的干细胞相比,hUCMSC具有来源广泛、可塑性强、对供者无不利影响、无伦理争论限制等优势,并且具有很强的向多组织分化的潜能,因此hUCMSC成为在组织工程、造血干细胞移植及基因治疗等研究领域具有巨大潜力的种子细胞,在临床应用方面有十分广阔的前景。     

人脐带间充质干细胞分离培养方法的研究

目的探讨人脐带间充质干细胞(MSCs)体外分离培养的最佳方法。方法无菌条件下采集早产儿(不足37周)和足月儿的脐带,分离MSCs,比较胎龄、脐带新鲜程度、分离方法和不同培养基对脐带MSCs原代培养过程的影响,通过免疫荧光法检测脐带MSCs表面标记物的表达情况,观察脐带MSCs的生物学特性。结果足月分娩,新鲜脐带,采用组织块平铺法和MesencultTM培养基,脐带MSCs原代培养成功率较高。相同条件下,早产儿脐带MSCs原代培养成功率低于足月分娩脐带。人脐带MSCs高表达CD44、CD90和CD29。结论筛选出一种人脐带MSCs体外分离培养的最佳方法。     

脐带间充质干细胞——组织工程的新视角

目的 从脐带中分离培养脐带间充质干细胞(mesenchymal stem cell, MSC) 并进行鉴定,阐明其多向分化的潜在作用.方法 收集健康胎儿脐带,分离培养脐带中的间充质干细胞,以流式细胞仪对培养的间充质干细胞进行细胞表面标志检测,多种成分联合诱导其向脂肪、成骨方向分化,细胞化学染色检测诱导后的细胞变化.结果 脐带中分离培养的间充质干细胞不表达造血细胞系的标志CD34、CD45、HLA-DR,强表达CD105、CD44、CD90,在适当的诱导条件下可向脂肪及成骨方向分化.结论 脐带中存在具有多向分化潜能的间充质干细胞.     

人脐带间充质干细胞在组织工程中的研究进展

人脐带间充质干细胞是一类具有自我更新、增殖和多向分化潜能的干细胞,具有来源广泛、易于采集、保存和运输、无异体排斥、避免伦理争议等诸多优点.流式细胞仪分析发现人脐带间充质干细胞高表达间质细胞标志(CD44、CD105)、整合素受体(CD29、CD49b、CD49c、CD51),不表达造血系标志(CD34、CD45)人白细胞抗原HLA-DR和内皮细胞标志CD31.人脐带间充质干细胞在体内外可以分化为骨细胞、软骨细胞、肝细胞、心肌细胞、骨骼肌细胞以及神经元细胞等.目前人脐带间充质干细胞在组织工程骨、人工血管以及基因治疗等临床应用研究中已逐渐深入,并已显示出广阔的应用前景.本文就人脐带间充质干细胞的生物学特性及其在组织工程中的研究作一综述.     

胎盘间充质干细胞的体外培养及其生物学特性研究

目的：探讨胎盘间充质干细胞（PMSCs）的体外分离和培养方法,建立稳定的PMSCs体外培养扩增体系。方法：将胎盘组织经胶原酶消化、密度梯度离心、贴壁筛选法分离,获得并培养人PMSCs,观察细胞形态及其超微结构;应用流式细胞术测定细胞周期及CD14、CD29、CD34、CD44、CD45的表达,研究其增殖和生长特性。结果：在体外培养条件下,人PMSCs贴壁生长,为成纤维细胞样,与骨髓间充质干细胞相似;CD14/CD34/CD45阴性,CD29/CD44阳性,核浆比大,细胞周期检测G0/G1期约占95%,具有原始细胞的特征。结论：体外获得的PMSCs形态单一、生长稳定、增殖能力较强,具有与骨髓间充质干细胞相似的细胞形态、表面标志。由于其来源方便、丰富,无伦理学限制,因此可进一步用于细胞治疗的研究。     

人脐带间充质干细胞抗肿瘤机制的研究进展

人脐带间充质干细胞(HUMSCs)是一种具有高度自我更新能力和多向分化潜能的干细胞群,具有分泌特定细胞因子、诱导肿瘤细胞凋亡、适用于基因编辑、安全性好及肿瘤趋向性等特性。有较多的研究者研究HUMSCs对肿瘤的作用,试图将HUMSCs作为肿瘤治疗的新方法。就HUMSCs抗肿瘤作用的研究进展作一综述。     

一种简单的人脐带间充质干细胞分离培养方法

目的 建立一种简单的人脐带间充质干细胞分离培养方法.方法 取新鲜脐带,剪成5 cm长的小段,直接剪碎为糊状,加入含10％胎牛血清的DMEM/F12在培养瓶中培养,光学显微镜下观察细胞的生长特征,运用流式细胞仪检测分析细胞的抗原标志表达,并检测其体外多向分化潜能.结果 运用不剥离血管组织、不用酶消化的组织贴块培养法可以从...     

Mesenchymal stem cells derived from human placenta suppress allogeneic umbilical cord blood lymphocyte proliferation

Human placenta-derived mononuclear cells （MNC） were isolated by a Percoll density gradient and cultured in mesenchymal stem cell （MSC） maintenance medium. The homogenous layer of adherent cells exhibited a typical fibroblastlike morphology, a large expansive potential, and cell cycle characteristics including a subset of quiescent cells. In vitro differentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic, osteogenic and chondrogenic lineages. Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was a homogeneous cell population devoid of hematopoietic cells, which uniformly expressed CD29, CD44, CD73, CD105, CD166, laminin, fibronectin and vimentin while being negative for expression of CD31, CD34, CD45 and m-smooth muscle actin. Most importantly, immuno-phenotypic analyses demonstrated that these cells expressed class Ⅰ major histocompatibility complex （MHC-I）, but they did not express MHC-Ⅱ molecules. Additionally these cells could suppress umbilical cord blood （UCB） lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli. This strongly implies that they may have potential application in allograft transplantation. Since placenta and UCB are homogeneous, the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells （HSC） from UCB to reduce the potential graft-versus-host disease （GVHD） in recipients.     

单纯生物学制剂诱导人脐带间充质干细胞向胰岛素分泌细胞快速分化

为探讨用单纯生物学制剂诱导人脐带间充质干细胞(mesenchymal stem cells derived from human umbilical cord,hUC-MSCs)向胰岛素分泌细胞分化的可行性,本研究用胶原酶Ⅱ、胰蛋白酶次序消化及两步离心法从人胎儿完整脐带中分离、纯化出hUC-MSCs;用表皮生长因子、碱性成纤维生长因子、银杏提取液和高糖培养基IMDM诱导hUC-MSCs向胰岛素分泌细胞分化。在hUC-MSCs诱导前后,用倒置显微镜观察其形态变化,RT-PCR检测其胰岛相关基因的表达;双硫腙染色鉴定胰岛样细胞团(islet-like clusters,ILCs);细胞免疫荧光染色检测ILCs中PDX-1和免疫活性胰岛素(immunoreactive insulin,IRI)的表达;化学发光法检测ILCs的IRI分泌量;Western blot鉴定IRI的性质。结果显示:纯化的hUC-MSCs呈间充质干细胞特有的形态特征:长梭形,平行或螺旋形排列;在上述单纯生物学制剂的诱导下,hUC-MSCs逐渐变圆并聚集成团;在25cm2培养瓶的细胞生长面可见上百个ILCs;ILCs表达胰岛特异性基因pdx-1、insulin;ILCs呈PDX-1和IRI免疫染色阳性反应,双硫腙染色呈阳性;ILCs可分泌IRI,但多为胰岛素原(proinsulin,PI)。以上结果提示,用表皮生长因子、碱性成纤维生长因子、银杏提取液和高糖培养基IMDM可诱导hUC-MSCs快速分化为胰岛素分泌细胞,但ILCs功能不够成熟,难以产生足量真胰岛素。     

The immunologic and hematopoietic profiles of mesenchymal stem cells derived from different sections of human umbilical cord

Mesenchymal stem cells （MSCs） have been widely used in allogeneic stem cell transplantation. We compared im- munologic and hematopoietic characteristics of MSCs derived from whole human umbilical cord （UC）, as well as from different sections of UCs, including the amniotic membrane （AM）, Wharton＇s jelly （WJ）, and umbilical vessel （UV）. Cell phenotypes were examined by flow cytometry. Lymphocyte transformation test and mixed lymphocyte reaction were performed to evaluate the immuno-modulatory activity of MSCs derived from UCs. The mRNA expression of cytokines was detected by real- time polymerase chain reaction. Hematopoietic function was studied by co-culturing MSCs with CD34＋ cells iso- lated from cord blood. Our results showed that MSCs separated from these four different sections including UC, W J, UV, and AM had similar biological characteristics. All of the MSCs had multi-lineage differentiation ability and were able to differentiate into osteoblasts, adipocytes, and chondrocytes. The MSCs also inhibited the proliferation of allogeneic T cells in a dose-dependent manner. The relative mRNA expression of cytokines was examined, and the results showed that UCMSCs had higher interleukin-6 （IL6）, ILll, stem cell factor, and FLT3 expression than MSCs derived from specific sections of UCs. CD34＋ cells had high propagation efficiencies when co-cultured with MSCs derived from different sections of UCs, among which UCMSCs are the most efficient feeding layer. Our study demonstrated that MSCs could be isolated from whole UC or specific sections of UC with similar immuno- modulation and hematopoiesis supporting characteristics.     

Optimization of primary culture condition for mesenchymal stem cells derived from umbilical cord blood with factorial design

Mesenchymal stem cells (MSCs) can not only support the expansion of hematopoietic stem cells in vitro, but also alleviate complications and accelerate recovery of hematopoiesis during hematopoietic stem cell transplantation. However, it proved challenging to culture MSCs from umbilical cord blood (UCB) with a success rate of 20–30%. Many cell culture parameters contribute to this outcome and hence optimization of culture conditions is critical to increase the probability of success. In this work, fractional factorial design was applied to study the effect of cell inoculated density, combination and dose of cytokines, and presence of serum and stromal cells. The cultured UCB‐MSC‐like cells were characterized by flow cytometry and their multilineage differentiation potentials were tested. The optimal protocol was identified achieving above 90% successful outcome: 2 × 10⁶ cells/mL mononuclear cells inoculated in Iscove's modified Dulbecco's medium supplied with 10% FBS, 15 ng/mL IL‐3, and 5 ng/mL Granulocyte‐macrophage colony‐stimulating factor (GM‐CSF). Moreover, the UCB‐MSC‐like cells expressed MSC surface markers of CD13, CD29, CD105, CD166, and CD44 positively, and CD34, CD45, and human leukocyte antigens‐DR (HLA‐DR) negatively. Meanwhile, these cells could differentiate into osteoblasts, chondrocytes, and adipocytes similarly to MSCs derived from bone marrow. In conclusion, we have developed an efficient protocol for the primary culture of UCB‐MSCs by adding suitable cytokines into the culture system. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009     

Immunomodulatory effects of umbilical cord‐derived mesenchymal stem cells

Umbilical cord blood (UCB) is of great interest as a source of stem cells for use in cellular therapies. The immunomodulatory effect of mesenchymal stem cells (MSCs) originating from bone marrow, adipose tissue and amniotic membrane has previously been reported. In this study, MSCs were isolated from UCB with the aim of evaluating their immunomodulatory effects on proliferation of PB lymphocytes by two different techniques; namely, 5‐bromo‐2‐deoxyuridine ELISA and a carboxy fluorescein diacetate succinimidyl ester flow cytometric technique. MSCs were isolated from UCB, propagated until Passage four, and then characterized for cell surface markers by flow cytometry and ability to differentiate towards osteocytes and adipocytes. Immunosuppressive effects on PB lymphocytes were examined by co‐culturing mitomycin C‐treated UCB MSCs with mitogen‐stimulated lymphocytes for 72 hr. Thereafter, proliferation of lymphocytes was detected by CFSE flow cytometry and colorimetric ELISA. The titers of cytokines in cell culture supernatant were also assayed to clarify possible mechanisms of immunomodulation. UCB MSCs suppressed mitogen‐stimulated lymphocyte proliferation, which occurs via both cell‐cell contact and cytokine secretion. Titers of transforming growth factor beta and IL 10 increased, whereas that of IFN‐γ decreased in the supernatants of co‐cultures. Thus, UCB MSCs suppress the proliferation of mitogen‐stimulated lymphocytes. However further in vivo studies are required to fully evaluate the immunomodulatory effects of UCB MSCs.     

Isolation of mesenchymal stem cells from human placenta: comparison with human bone marrow mesenchymal stem cells

The presence within bone marrow of a population of mesenchymal stem cells (MSCs) able to differentiate into a number of different mesenchymal tissues, including bone and cartilage, was first suggested by Friedenstein nearly 40 years ago. Since then MSCs have been demonstrated in a variety of fetal and adult tissues, including bone marrow, fetal blood and liver, cord blood, amniotic fluid and, in some circumstances, in adult peripheral blood. MSCs from all of these sources can be extensively expanded in vitro and when cultured under specific permissive conditions retain their ability to differentiate into multiple lineages including bone, cartilage, fat, muscle, nerve, glial and stromal cells. There has been great interest in these cells both because of their value as a model for studying the molecular basis of differentiation and because of their therapeutic potential for tissue repair and immune modulation. However, MSCs are a rare population in these tissues. Here we tried to identify cells with MSC-like potency in human placenta. We isolated adherent cells from trypsin-digested term placentas and examined these cells for morphology, surface markers, and differentiation potential and found that they expressed several stem cell markers. They also showed endothelial and neurogenic differentiation potentials under appropriate conditions. We suggest that placenta-derived cells have multilineage differentiation potential similar to MSCs in terms of morphology and cell-surface antigen expression. The placenta may prove to be a useful source of MSCs.