Critical parameters for the isolation of mesenchymal stem cells from umbilical cord blood

Evidence has emerged that mesenchymal stem cells (MSCs) represent a promising population for supporting new clinical concepts in cellular therapy. However, attempts to isolate MSCs from umbilical cord blood (UCB) of full-term deliveries have previously either failed or been characterized by a low yield. We investigated whether cells with MSC characteristics and multi-lineage differentiation potential can be cultivated from UCB of healthy newborns and whether yields might be maximized by optimal culture conditions or by defining UCB quality criteria. Using optimized isolation and culture conditions, in up to 63% of 59 low-volume UCB units, cells showing a characteristic mesenchymal morphology and immune phenotype (MSC-like cells) were isolated. These were similar to control MSCs from adult bone marrow (BM). The frequency of MSC-like cells ranged from 0 to 2.3 clones per 1 x 10(8) mononuclear cells (MNCs). The cell clones proliferated extensively with at least 20 population doublings within eight passages. In addition, osteogenic and chondrogenic differentiation demonstrated a multi-lineage capacity comparable with BM MSCs. However, in contrast to MSCs, MSC-like cells showed a reduced sensitivity to undergo adipogenic differentiation. Crucial points to isolate MSC-like cells from UCB were a time from collection to isolation of less than 15 hours, a net volume of more than 33 ml, and an MNC count of more than 1 x 10(8) MNCs. Because MSC-like cells can be isolated at high efficacy from full-term UCB donations, we regard UCB as an additional stem cell source for experimental and potentially clinical purposes.     

人脐静脉来源的间质干细胞体外分离扩增及多向分化的研究

目的： 探讨人脐静脉来源的间质干细胞(MSCs) 的体外分离、纯化、扩增和多向分化条件。 方法： 无菌条件下取正常人脐静脉,1%胶原酶Ⅱ消化脐静脉细胞，以IMDM作为培养基进行培养和纯化细胞，瑞氏染色和电镜观察形态；FACS检测其免疫表型和细胞周期；体外诱导成骨细胞、脂肪细胞分化，von Kossa染色、油红O染色和RT-PCR检测骨钙蛋白、脂蛋白脂酶mRNA的表达以检测细胞向成骨、成脂肪细胞分化情况。 结果： 脐静脉来源的细胞呈纤维样贴壁生长，瑞氏染色和电镜观察具有MSCs特征；FACS检测结果显示, 表达MSCs相关的抗原CD29、CD44、CD105，而CD31、CD13、CD34、CD45、HLA-DR为阴性；体外诱导成骨细胞、脂肪细胞分化成功。 结论： 人脐静脉来源的MSCs的细胞形态、生长特性、免疫表型、多向分化能力与骨髓来源的MSCs相似，可作为满足实验和临床需要的MSCs来源。     

A rapid, simple, and reproducible method for the isolation of mesenchymal stromal cells from Wharton's jelly without enzymatic treatment

The co-infusion of mesenchymal stromal cells (MSCs) with hematopoietic stem cells could improve the hematopoietic engraftment after cord blood transplant. Adult bone marrow is the major source of MSCs for cell therapy. However, bone marrow aspiration involves an invasive procedure and, in the case of a cord blood transplant, requires the use of a third party. The umbilical cord matrix, called Wharton's jelly (WJ), was previously shown to be a valuable source of MSCs. However, the process of cell separation is not standardized and needs to be optimized. In this study, we focused on the efficiency of the isolation procedure and expansion of cells from WJ MSCs isolated from human full-term umbilical cords. MSCs were isolated from the WJ without enzyme digestion or dissection. The procedure was based only on the plastic adhesion capacities of MSCs. Briefly, umbilical cord segments of 5-10?cm were cut longitudinally and plated with the WJ onto a plastic surface for 5 days in an appropriate culture medium. After removing the cord segment, the culture was pursued until subconfluency. The number of cells and their phenotypes, clonogenic capacities, differentiation capacities, immunomodulation, and hematopoietic supportive functions were evaluated. Using this method, we were able to isolate MSCs from all human umbilical cords analyzed (n?=?50). We obtained a mean of 1.4?×?10(8) cells at the second passage and >7?×?10(9) cells at the third. The expanded cells expressed characteristic markers and presented typical functional properties of MSCs such as differentiation capacities, immunologic properties, and hematopoietic supportive functions. In conclusion, we have established a simple, rapid, and reproducible protocol to isolate abundant MSCs from short segments of umbilical cords.     

体外诱导人脐静脉间充质干细胞分化为神经元样细胞的实验研究

探讨来源于人脐静脉内皮及内皮下分离的间充质干细胞(MSCs)向神经元样细胞分化的可能性,以期为脐静脉MSCs的神经移植提供理论依据。通过在无菌条件下收集正常足月剖宫产新生儿脐带并对脐静脉进行胶原酶消化,将获取的内皮及内皮下贴壁细胞进行培养。经传代培养及免疫细胞化学鉴定后,取第2代细胞用β-巯基乙醇和二甲基亚砜诱导其向神经元方向分化,并以免疫细胞化学方法对分化细胞进行鉴定。结果表明脐静脉经胶原酶消化后的贴壁细胞主要表现为间充质样细胞和内皮细胞;传2代后,间充质样细胞可得到纯化和扩增。免疫细胞化学染色显示诱导前细胞不表达血管性血友病因子(vWF),诱导后MSCs表达巢蛋白(nestin)和神经元特异性烯醇化酶(NSE),而不表达胶质纤维酸性蛋白(GFAP)。以上结果提示,来源于脐静脉内皮及内皮下的MSCs在体外可以培养、扩增,并具备在诱导剂的作用下向神经元样细胞分化的潜能,可作为神经系统疾病细胞移植治疗的备选来源。     

体外模拟干细胞微环境培养扩增脐血及脐带基质源性间充质干细胞**

背景：建立稳健的扩增体系,在体外扩增时最大限度地获得治疗剂量的干细胞数,同时保存干细胞的特性是临床实验室亟待解决的问题。 目的：建立体外模拟干细胞微环境细胞外基质扩增脐血间充质干细胞及脐带间充质干细胞的方法,并与传统的2-D培养体系比较。 方法：建立体外模拟干细胞微环境细胞外基质,体外分离脐血间充质干细胞及脐带间充质干细胞后分别接种到细胞外基质及传统的2-D塑料培养体系,分别从细胞计数及细胞表面标志物的变化,评估两种扩增体系对脐血间充质干细胞及脐带间充质干细胞体外扩增的优劣。 结果与结论：使用骨髓源性的细胞外基质培养体系单位时间脐血间充质干细胞及脐带间充质干细胞产量是2-D体系的4~6倍,并且流式细胞仪检测显示细胞外基质体系能更好地保持干细胞的表面标记。因此,3-D较2-D培养系更接近生理环境,已建立的骨髓源性细胞外基质培养体系能保持间充质干细胞的特性,为短时间内快速获取更大数目同质、高活性的间充质干细胞提供了可能。 关键词：脐血间充质干细胞;脐带间充质干细胞;细胞外基质;2-D培养板;培养扩增 doi:10.3969/j.issn.1673-8225.2012.10.011     

足月小样儿及正常胎儿脐血间充质干细胞的分离培养及形态学观察

目的建立一种简单实用的脐血间充质干细胞(MSCs)的分离培养方法,观察其生物学特性,为脐血MSCs在临床的广泛应用奠定基础。方法无菌条件下采集足月小样儿和足月正常胎儿分娩脐血,密度梯度离心法分离脐血单个核细胞,采用MesencultTM培养基培养,观察脐血MSCs的生物学特性,免疫荧光方法检测其表面标记物的表达情况。结果采用MesencultTM培养基,正常儿脐血MSCs培养成功率为66.67%,相同培养条件下,足月小样儿脐血培养成功率低于正常体重胎儿的脐血。人脐血MSCs强表达CD29、CD44和CD90,不表达造血干细胞表面标志CD34。结论我们建立了最佳的脐血MSCs的分离培养方法。     

The osteogenic differentiation potentials of umbilical cord blood hematopoietic stem cells

Under specific culture conditions, umbilical cord blood derived mesenchymal stem cells (MSCs) can differentiate into osteogenic, adipogenic, and chondrogenic lineages. The purpose of the current study was to assess the differentiation potential of osteogenic umbilical cord blood derived hematopoietic stem cells (HSCs) and to develop an appropriate osteogenic differentiation medium for in vitro differentiation of umbilical cord blood derived HSCs. The study was conducted on 20 cord blood samples. The cells were cultured in osteogenic differentiating medium for 3?weeks. The HSCs differentiated into osteoblasts, which expressed osteoblast-associated genes (osteocalcin and bone sialoprotein), which were detected by RT-PCR. They showed alkaline phosphatase activity and a positive Alizarin red-S (AR-S) stain (calcium phosphate deposition). Umbilical cord blood is a rich source of hematopoietic stem cells that can be differentiated into osteoblasts; thus, it can be used for therapeutic strategies in the context of regenerative therapy.     

人脐带间充质干细胞诱导成骨及治疗骨缺损

背景：人脐带间充质干细胞在成骨及组织器官修复方面具有更强的扩增能力及低免疫原性,其成集落生长潜能及成骨时间早于骨髓等其他来源间充质干细胞。 目的：观察脐带间充质干细胞诱导成骨及移植治疗骨缺损的临床效果。 方法：应用组织块贴壁法提取人脐带间充质干细胞,体外行成骨诱导并通过光镜观察、茜素红染色、碱性磷酸酶染色、Ⅰ型胶原的表达等证实其体外成骨能力;对临床骨缺损病例行人脐带间充质干细胞移植,移植后定期复查骨缺损部骨痂生长状况。   结果与结论：体外诱导证实人脐带间充质干细胞具有明确的成骨作用。骨缺损患者在人脐带源间充质干细胞移植后2个月X射线见左股骨髁上骨折部位骨块间隙模糊,骨折外周形成明显的骨痂,骨折断端相连,断端骨折线依然存在;移植后3个月见骨痂间已经形成明显骨性连接。证实脐带间充质干细胞具有体外诱导成骨及体内移植修复骨缺损作用。     

体外分离培养胎盘多分化潜能细胞的实验研究

目的 探索一种新的获取间充质干细胞（mesemchymal stem cells，MSCs）的来源及方法。MSCs在成人骨髓内含量极低．数量随着年龄的增长而减少。MSCs同时少量出现于外周血以及脐带血、胎儿组织器官内，然而，胎儿组织样本难以获取，脐带血中含量太低。这样，如何获得合适的MSCs来源以建立稳定的培养体系．同时避免伦理道德问题的约束是一个值得探索的课题。方法 消化胎盘实体组织，贴壁培养细胞，观测形态并检测其细胞表面抗原表达以及分化潜能。结果 胎盘组织中分离出的贴壁细胞与骨髓间充质干细胞有相似形态和细胞表面标志，具有分化为成骨细胞以及神经细胞的能力。结论 胎盘组织中含有的多分化潜能细胞（placenta．derived muhipotent cells，PDMCs）与骨髓MSCs形态功能相似．胎盘可以作为获取MSCs的一种有效来源。     

人脐血源性MSCs的免疫调节作用

目的 从人脐血中分离、培养间充质干细胞(MSCs)并探讨其对淋巴细胞的免疫调节作用.方法 淋巴细胞分离液分离人脐血单个核细胞,利用贴壁筛选法通过多次传代得到MSCs,流式细胞仪测定细胞表型;将获得的MSCs分别以不同数量加入到外周血混合淋巴细胞培养体系和植物血凝素(PHA)刺激的外周血淋巴细胞转化体系中,用H3-TdR标记β液体闪烁计数仪检测细胞增殖,观察脐血来源的MSCs对混合淋巴细胞反应和淋巴细胞转化的影响.结果 从人脐血中分离获得的贴壁细胞,呈成纤维样的细胞形态,CD29、CD105和CD166表达阳性,CD14、CD34和CD45表达阴性;人脐血源性MSCs在体外对混合淋巴细胞反应和PHA诱导的淋巴细胞转化均具有明显的抑制作用,抑制作用与细胞数量呈正相关.结论 从人脐血中可以成功地分离出MSCs,其对同种异体淋巴细胞具有免疫调节作用,为其作为骨组织工程异基因种子细胞来源打下基础.     

Optimization of culture conditions for the expansion of umbilical cord-derived mesenchymal stem or stromal cell-like cells using xeno-free culture conditions

First isolated from bone marrow, mesenchymal stem or stromal cells (MSC) were shown to be present in several postnatal and extraembryonic tissues as well as in a large variety of fetal tissues (e.g., fatty tissue, dental pulp, placenta, umbilical cord blood, and tissue). In this study, an optimized protocol for the expansion of MSC-like cells from whole umbilical cord tissue under xeno-free culture conditions is proposed. Different fetal calf sera and human serum (HS) were compared with regard to cell proliferation and MSC marker stability in long-term expansion experiments, and HS was shown to support optimal growth conditions. Additionally, the optimal concentration of HS during the cultivation was determined. With regard to cell proliferative potential, apoptosis, colony-forming unit fibroblast frequency, and cell senescence, our findings suggest that an efficient expansion of the cells is carried out best in media supplemented with 10% HS. Under our given xeno-free culture conditions, MSC-like cells were found to display in vitro immunoprivileged and immunomodulatory properties, which were assessed by co-culture and transwell culture experiments with carboxyfluorescein diacetate succinimidyl ester-labeled peripheral blood mononuclear cells. These findings may be of great value for the establishment of biotechnological protocols for the delivery of sufficient cell numbers of high quality for regenerative medicine purposes.     

诱导脐血间充质干细胞向神经元样细胞分化

背景：脐血来源的间充质干细胞具有与造血干细胞和骨髓间充质干细胞相似的多向分化潜能,并且可以诱导分化为神经元样细胞,但分离培养后的成功率比较低,需要寻求一种成功率较高的培养方法。 目的：探讨脐血间充质干细胞的生物学特性及向神经元样细胞诱导分化的方法。 方法：由作者检索CNKI数据库2002/2011收录的有关脐血间充质干细胞诱导分化为神经元样细胞的相关研究文献,中文检索词为“脐血间充质干细胞,神经细胞,诱导分化,细胞因子”。 结果与结论：脐血间充质干细胞具有与造血干细胞和骨髓间充质干细胞相似的多向分化潜能,可以在体外诱导分化为神经样细胞,对CD34表达阴性,是区别于脐血造血干细胞的主要标志物。脐血间充质干细胞在体外诱导分化的方法主要有细胞生长因子法、化学诱导剂法、生长因子与诱导剂联合法,通过各种神经诱导剂的作用,使培养出的神经元样细胞数量有所增加,国内外基础研究结果显示移植脐血间充质干细胞诱导分化的神经元样细胞可以修复中枢神经系统损伤性疾病,脐血间充质干细胞是神经损伤修复的一种理想种子细胞。     

Stem cells in the umbilical cord

Stem cells are the next frontier in medicine. Stem cells are thought to have great therapeutic and biotechnological potential. This will not only to replace damaged or dysfunctional cells, but also rescue them and/or deliver therapeutic proteins after they have been engineered to do so. Currently, ethical and scientific issues surround both embryonic and fetal stem cells and hinder their widespread implementation. In contrast, stem cells recovered postnatally from the umbilical cord, including the umbilical cord blood cells, amnion/placenta, umbilical cord vein, or umbilical cord matrix cells, are a readily available and inexpensive source of cells that are capable of forming many different cell types (i.e., they are “multipotent”). This review will focus on the umbilical cord-derived stem cells and compare those cells with adult bone marrow-derived mesenchymal stem cells.     

丹参素联合生长因子体外诱导人脐血间充质干细胞分化为神经细胞的研究

人脐血间充质干细胞(MSCs)是从脐带血中分离和培养的一种多潜能成体干细胞。本实验通过密度梯度离心法分离人脐血单个核细胞,贴壁法筛选出脐血MSCs,体外扩增,免疫荧光方法检测表面抗原。传3代的脐血MSCs经20ng/mlbFGF预诱导24h、3μg/μl丹参素诱导6h、20ng/mlEGF和20ng/mlbFGF诱导分化5d后出现类似神经元样细胞的形态改变,伸出长突起。免疫组织化学和免疫荧光方法鉴定显示,诱导后的细胞能特异性表达神经元特异性标志NeuN和β-TubulinⅢ,而星形胶质细胞特异性标志GFAP阳性细胞较少。上述结果表明,丹参素联合生长因子EGF和bFGF在体外可定向诱导人脐血MSCs分化为神经元样细胞。     

冻存脐带间充质干细胞向成骨细胞的分化

背景：在骨组织工程中,脐带间充质干细胞是的一种新兴的种子细胞。目前认为低温冻存是长期保存细胞的有效方法。 目的：探究冻存的脐带间充质干细胞能否被诱导分化成成骨细胞。 方法：采用组织块贴壁法从脐带的华尔通氏胶组织中分离出间充质干细胞。然后,用倒置显微镜观察原代细胞的细胞形态。脐带间充质干细胞的免疫表型和细胞周期用流式细胞仪检测。在冻存6个月后,复苏第2代脐带间充质干细胞进行冻存复苏,并传代培养至12代。对第12代的脐带间充质干细胞进行成骨诱导,它的成骨能力分别通过碱性磷酸酶活性检测,骨钙素和骨涎蛋白的免疫荧光检测以及茜素红染色检测来 确定。 结果与结论：原代脐带间充质干细胞呈现典型的成纤维细胞样形态。流式细胞仪显示培养的细胞高表达间充质干细胞的表面标志CD73、CD105和CD90,但是不表达造血细胞的表面标志CD34和CD45。复苏后细胞的存活率是90%。细胞周期显示P8的细胞有75%处于G₀/G₁期,25%处于S+G₂M期。经成骨诱导液处理的第12代细胞显示出比对照组更高的碱性磷酸酶活性(P < 0.01)。此外,在成骨诱导液中诱导的细胞对骨钙素和骨涎蛋白的染色呈阳性,并形成矿化了结节。冻存后的脐带间充质干细胞仍保持了它们的生物学特性,并且在成骨诱导液中能被诱导分化成成骨细胞。     

干细胞在神经创伤修复中的应用

背景：干细胞具有很强的增殖和分化能力,已在神经组织损伤修复方面展示了不可估量的临床应用前景。但是,目前有关神经干细胞的组织来源、定向诱导分化、移植技术和神经功能修复的功能判定等方面尚存在诸多难题。 目的：阐述干细胞在神经创伤修复中的应用研究进展。 方法：检索干细胞在神经创伤修复应用中的相关研究文献,检索词为“干细胞(stem cell),骨髓间充质干细胞(bone marrow mesenchymal stem cells),神经干细胞(neural stem cell),胚胎干细胞(embryonic stem cell),脂肪干细胞(adipose-derived stem cells),脐血干细胞(umbilical cord blood stem cells),成体干细胞(adult stem cells),脑损伤/创伤性脑损伤(traumatic brain injury),脊髓损伤(spinal cord injury),神经创伤(traumatic nerve injury),生长因子(growth factor),修复(repair)”,语言分别设定为中文和英文,对骨髓间充质干细胞、神经干细胞、胚胎干细胞、脐血干细胞及脂肪干细胞在神经创伤修复中的应用研究进行深入分析。 结果与结论：干细胞是一类具有自我更新、高度增殖和多向分化潜能的特殊细胞,其最显著的生物学特性是既有自我更新的能力,又具有多向分化的潜能。目前,已经从许多组织或器官中成功地分离出,其中包括胚胎干细胞,造血干细胞和骨髓间质干细胞等。此外,还有近来研究渐多的神经干细胞、肌肉干细胞、成骨干细胞、内胚层干细胞及视网膜干细胞等。干细胞的多向分化潜能为神经创伤修复开辟了新的途径,其在脑损伤以及脊髓损伤后的神经修复以及功能重建的研究方面已取得很大的进展,被认为具有广阔的应用前景,与之相关的问题均有待于进一步的研究     

间充质干细胞的成骨细胞分化和免疫组织化学鉴定

目的 探讨脐带的间充质干细胞分化为成骨细胞的影响因素和免疫组织化学鉴定。 方法 收集306例冻存的健康胎儿脐带,采用华尔通胶组织块贴壁法从脐带组织中分离间充质干细胞,利用荧光显微镜观察原代细胞的细胞形态。脐带间充质干细胞的免疫表型和细胞周期采用免疫组织化学检测。复苏冻存的脐带间充质干细胞,并传代培养至10代。对第10代的脐带间充质干细胞进行成骨诱导,其成骨能力分别通过钙结节和骨涎蛋白的免疫荧光检测以及茜素红染色检测来确定。 结果 免疫组织化学结果显示,培养的细胞高表达间充质干细胞的表面标志物CD73、CD90和CD105,但是不表达造血细胞的表面标志物CD34和CD45。复苏后细胞的存活率是90%。细胞周期显示,第10代的细胞有80%处于G₀/G₁期,20%处于S+G₂/M期。成骨细胞刺激因子诱导干细胞的骨涎蛋白染色呈阳性,并形成矿化的钙结节。 结论 冻存的脐带间充质干细胞在成骨细胞刺激因子下能被诱导分化为成骨细胞,具有高度自我增殖和多向分化能力。     

人脐带间充质干细胞与肝细胞共培养可分化为肝样细胞

背景：文献报道,从骨髓与脐带中分离获得的间充质干细胞可在体外连续传代培养,仍保持干细胞的特性,并在多种细胞因子的“鸡尾酒式”诱导下分化为肝细胞样细胞。 目的：进一步验证人脐带间充质干细胞在体外正常人肝细胞共培养体系下是否可分化为肝细胞并探讨其分化方法。 方法：采用贴壁法,从脐带中分离培养间充质干细胞,流式细胞仪检测脐带间充质干细胞表面标志。人肝细胞LO2细胞与人脐带间充质干细胞建立共培养体系,不添加外源诱导因子,分别于第7,14,21天,通过RT-PCR 法检测肝细胞特异标志物甲胎蛋白、白蛋白、人细胞角蛋白19 mRNA的表达,糖原染色进行功能鉴定。 结果与结论：从人脐带中可分离得到贴壁生长的间充质干细胞,其中CD29⁺细胞比例为96.02%,CD105⁺细胞比例为96.6%,CD34^-细胞比例为99.65%,CD105⁺CD29⁺双阳性细胞比例为94.84%。与LO2细胞共培养后第7天仅有甲胎蛋白阳性表达;第14天表达白蛋白、人细胞角蛋白19,第21天时,LO2与人脐带间充质干细胞共培养组未出现甲胎蛋白表达;人细胞角蛋白19和白蛋白的表达比第14天略有增强。共培养21 d后,糖原染色呈阳性。结果证实,无需额外添加外源诱导因子,脐带间充质干细胞可在人正常肝细胞共培养的微环境中,向正常肝细胞分化。     

人脐血源性MSCs成骨诱导分化后的免疫调节作用

目的:探讨脐血源性间充质干细胞(mesenchymal stem cells,MSCs)经成骨诱导分化后,其对淋巴细胞的免疫调节作用。方法:从人脐血中分离、培养及扩增MSCs,流式细胞仪测定细胞表型;将获得的MSCs在成骨诱导体系中诱导分化并鉴定,将诱导后的成骨细胞分别以不同剂量加入到外周血混合淋巴细胞培养体系和植物血凝素(PHA)刺激的外周血淋巴细胞转化体系中,用3H-TdR标记β液体闪烁计数仪检测细胞增殖,观察对混合淋巴细胞反应和淋巴细胞转化的影响。结果:从人脐血中分离获得的MSCs,呈成纤维样的细胞形态,CD29和CD105表达阳性,CD34和CD45表达阴性;在成骨诱导剂诱导下,具有成骨细胞样表型,可表达碱性磷酸酶,并形成矿化结节;人脐血源性MSCs经成骨诱导分化后在体外对混合淋巴细胞反应和PHA诱导的淋巴细胞转化均具有明显的抑制作用,抑制作用与细胞数量呈正相关。结论:脐血源性MSCs诱导为成骨细胞后对同种异体淋巴细胞具有免疫调节作用,为其作为骨组织工程异基因种子细胞来源打下基础。