人脐带间充质干细胞分离培养及向脂肪与成骨细胞的分化**△○

背景：研究报道显示人脐带间充质干细胞体外分离方法及效率、培养条件各不相同,并且尚未有统一的鉴定标准。因此建立高效、经济的培养体系十分必要。 目的：本研究旨在建立从人脐带组织分离培养间充质干细胞的方法,并进行向脂肪细胞和成骨细胞的诱导分化。 方法：首先采用组织块贴壁法或酶消化法分离纯化得到脐带间充质干细胞(Umbilical cord mesenchymal stem cells,UCMSCs),分析其细胞形态、增殖方式和某些免疫表型,并在体外诱导其向脂肪细胞和成骨细胞分化。 结果和结论:结果发现,hUCMSCs在适当的诱导条件下能向脂肪和成骨细胞分化,体外能连续传代40次以上,且形态和表型保持稳定。这证实了人脐带组织存在间充质干细胞,且具有向脂肪和成骨细胞分化的潜能,该细胞可用于后续的应用研究。     

原子力显微镜观察人脐带间充质干细胞：生物学特性与超微结构的关系*

背景：细胞形态结构和功能密不可分,但目前对人脐带间充质干细胞超微结构的报道还很少。 目的：探讨人脐带间充质干细胞的生物学特性与原子力显微镜下超微结构的关系。 方法：采用酶消化法体外分离培养并扩增人脐带间充质干细胞,取第3代细胞,用原子力显微镜在接触模式下观察成像,通过流式细胞仪检测细胞免疫表型和细胞周期,油红O染色及碱性磷酸酶染色鉴定其成脂、成骨分化潜能。 结果与结论：第3代人脐带间充质干细胞强表达CD44,CD29,低表达CD106,不表达CD34;有80%以上的细胞处在G0/G1期,增殖指数为19.9%;成脂诱导后,油红O染色可见胞浆中有大量桔红色的小脂滴;成骨诱导后,碱性磷酸酶染色可见立方形、多边形细胞的胞质染成棕褐色。原子力显微镜下人脐带间充质干细胞以长梭形为主,细胞骨架丝明显,并形成网状连接,这与其强大的增殖、迁移、分化功能相适应。     

人脐带间充质干细胞分离培养及成骨分化*

背景：目前,人们对间充质干细胞的观察研究多采用扫描电镜、透射电镜和倒置显微镜等,但是这几种方法对观察细胞膜超微结构及细胞骨架的研究则有不足之处。 目的：探讨并优化人脐带间充质干细胞体外获取及培养增殖的方法并鉴定;应用原子力显微镜观察其向成骨诱导过程中超微结构的变化。 方法：用酶消化法分离培养人脐带间充质干细胞,通过传代培养,扩增。体外向骨方向诱导分化,并通过碱性磷酸酶钙钴法染色、茜素红染色鉴定其分化能力。流式细胞仪检测人脐带间充质干细胞免疫表型;诱导过程中利用原子力显微镜的高空间分辨率从可视化的角度观察其在诱导前后细胞表面超微结构的变化。 结果与结论：采用酶消化法能有效分离纯化人脐带间充质干细胞。接种24 h,贴壁细胞形态多为长梭形,多边形或成纤维细胞样形态,大小均一。流式细胞仪分析第3代细胞均表达CD29、CD44 、CD105,不表达CD34、CD45和HLA-DR。经成骨诱导分化4周后,碱性磷酸酶染色呈强阳性,茜素红染色可见明显钙结节;通过原子力显微镜对分化前后的细胞骨架分析：未分化的干细胞其细胞骨架的微管突出不明显,分化后的细胞骨架其微管明显突出,并呈平行分布状态。     

人脐带间充质干细胞冻存复苏后细胞表面标志物分子学变化

背景：间充质干细胞是具有自我更新能力且能够多向分化的干细胞。脐带属于胚胎外组织,是胎儿分娩后的废弃物,来源广泛,无伦理学限制,因此有望作为间充质干细胞来源的第一选择。 目的：检测人脐带间充质干细胞冻存复苏前后细胞表面分子CD29、CD44、CD49e、CD73、CD90、CD34、CD45、CD271标志变化情况。 方法：通过从人的脐带中分离培养间充质干细胞,分别观察原代细胞、P4、P8代细胞和冻存复苏后P2、P4、P8代细胞形态;通过流式细胞仪检测原代细胞、P4、P8代细胞和冻存复苏后P2、P4、P8代细胞表面分子标志CD29、CD44、CD49e、CD73、CD90、CD34、CD45、CD271。 结果与结论：人脐带间充质干细胞冻存前与原代复苏后不同代数下细胞均表现出相同的表型,CD29、CD44、CD49e、CD73、CD90阳性,CD34、CD45、CD271阴性,提示人脐带间充质干细胞原代低温冻存复苏后细胞表面标志性分子无变化。     

脐带间充质干细胞的分离培养及诱导分化为多巴胺能样神经元

目的 探索脐带间充质于细胞(MSCs)的分离培养及将其诱导分化为多巴胺能神经元的方法.方法 分离脐带间充质组织,Ⅳ型胶原酶消化分离脐带MSCs,原代培养于含10%FBS的DMEM/F12培养基中,观察细胞形态并应用流式细胞仪检测细胞表面标志物和细胞周期,CCK8法绘制细胞生长曲线;采用二步法诱导分化P3代脐带MSCs,培养3、6、9 d后终止诱导,应用免疫荧光染色和Wcstern blotting检测分化后细胞酪氨酸羟化酶(TH)、神经元特异性烯醇化酶(NSE)的表达.结果 分离培养的脐带MSCs形态呈相对均一的成纤维样细胞,平行排列或旋涡状生长.P3代细胞CD29、CD44、CD73、CD90、CD105、CD166表达阳性,而CD34、CD45、CD19、CD31、HLA-DR表达阴性.对数生长期细胞倍增时间为48 h,处于G0～G1期细胞占91.13%;诱导分化后细胞多数为两级,形态与神经元相似,免疫荧光染色检测结果显示诱导9 d时细胞NSE、TH染色阳性率分别为19.5%和8.9%,Weston blotting检测结果显示诱导6 d时细胞NSE表达明显,TH仅有弱表达,诱导9 d时TH、NSE均表达明显.结论 脐带间充质组织中能分离出MSCs,且能分化成多巴胺能神经元.

Abstract：

Objective To investigate the methods of isolation of human umbilical cord mesenchymal stem cells (MSCs) in Wharton' s jelly and the differentiation of MSCs into dopaminergic neurons. Methods The umbilical cord mesenchymal tissue was scraped off from the Wharton's jelly,and then, collagenase Ⅳ was employed to isolate the MSCs. The isolated cells were primarily cultured in DMEM/F12 medium containing 10% FBS. Inverted microscopy was used to observe the cytomorphology, and flow cytometry was employed to detect the cell surface antigens and the cell cycle.We evaluated the cell viability using CCK8 kit. Two-step method was employed to induce the MSCs of the P3 generation to differentiate into dopaminergic neurons, and immunocytochemistry and Western blotting were used to detect the expressions of neuron specific enolase (NSE) and tyrosine hydroxylase (TH) 3, 6 and 9 d after the induction. Results The isolated MSCs showed fibroblast-like shape, with parallel arrangement and vortex-like growth. MSCs of the P3 generation expressed CD73, CD29, CD44and CD105, but did not express CD34, CD45, CD106 and HLA-DR. The doubling time in the exponential phase was at the 48th h of culture, and 91.13% cells were under G0-G1. These cells had similar morphology of the neurons. The immunocytochemical assay showed that the NSE and TH positive rates were 19.5% and 8.9% on the 9th d of induction; and Western blotting showed that MSCs obviously expressed NSE and weakly expressed TH.Conclusion MSCs can be isolated from the umbilical cord mesenchymal tissue, and be induced to differentiate into dopaminergic neurons in vitro.     

Neural cell injury microenvironment induces neural differentiation of human umbilical cord mesenchymal stem cells

This study aimed to investigate the neural differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs) under the induction of injured neural cells. After in vitro isolation and culture, passage 5 hUCMSCs were used for experimentation. hUCMSCs were co-cultured with normal or Aβ_1-40-injured PC12 cells, PC12 cell supernatant or PC12 cell lysate in a Transwell co-culture system. Western blot analysis and flow cytometry results showed that choline acetyltransferase and microtubule-associated protein 2, a specific marker for neural cells, were expressed in hUCMSCs under various culture conditions, and highest expression was observed in the hUCMSCs co-cultured with injured PC12 cells. Choline acetyltransferase and microtubule-associated protein 2 were not expressed in hUCMSCs cultured alone (no treatment). Cell Counting Kit-8 assay results showed that hUCMSCs under co-culture conditions promoted the proliferation of injured PC12 cells. These findings suggest that the microenvironment during neural tissue injury can effectively induce neural cell differentiation of hUCMSCs. These differentiated hUCMSCs likely accelerate the repair of injured neural cells.     

Neurogenic potential of human umbilical cord blood: neural-like stem cells depend on previous long-term culture conditions

In vitro studies conducted by our research group documented that neural progenitor cells can be selected from human umbilical cord blood (HUCB-NPs). Due to further expansion of these cells we have established the first human umbilical cord blood-derived neural-like stem cell line (HUCB-NSC) growing in serum-free (SF) or low-serum (LS) medium for over 3 years. The purpose of the study was to evaluate the neurogenic potential of HUCB-NSCs cultured in SF and LS condition in different in vitro settings before transplantation. We have shown that the number of cells attaining neuronal features was significantly higher for cultures expanded in LS than in SF condition. Moreover, the presence of neuromorphogens, cultured rat astrocytes or hippocampal slices promoted further differentiation of HUCB-NSCs into neural lineage much more effectively when the cells had derived from LS cultures. The highest response was observed in the case of co-cultures with rat primary astrocytes as well as hippocampal organotypic slices. However, the LS cells co-cultured with hippocampal slices expressed exclusively a set of early and late neuronal markers whereas no detection of cells with glial-specific markers was possible. In conclusion, certain level of stem/progenitor cell commitment is important for optimal response of HUCB-NSC on the neurogenic signals provided by surrounding environment in vitro.     

CM-Dil体外标记人脐带间充质干细胞传代示踪的可行性

背景：掌握人脐带间充质干细胞的移植示踪方法是研究其生物学特性的关键。 目的：观察用CM-Dil标记人脐带间充质干细胞及在体外传代示踪的可行性。 方法：采用酶消化法体外分离培养人脐带间充质干细胞,通过流式细胞仪检测细胞免疫表型和细胞周期、体外成脂成骨诱导鉴定该细胞。将第5代细胞用CM-Dil标记,并将细胞传代,荧光显微镜观察体外标记情况。 结果与结论：第3代人脐带间充质干细胞强表达CD44,CD29,低表达CD106,不表达CD34、CD40;有80%以上的细胞处在G0/G1期,成脂成骨诱导后,油红O染色和碱性磷酸酶染色分别阳性。CM-Dil标记人脐带间充质干细胞细胞标记率达90%以上,体外传代后荧光强度逐渐减退,传8代后,荧光基本消失。说明人脐带间充质干细胞增殖、分化能力强,CM-Dil标记细胞示踪方法简单易行。     

Estrogen stimulates the neuronal differentiation of human umbilical cord blood mesenchymal stem cells (CD34-)

This study evaluated the effects of estrogen on the neuronal differentiation of human umbilical cord blood mesenchymal stem cells. Human umbilical cord blood mesenchymal stem cells cultured in a neuronal differentiation medium containing dimethylsulfoxide and butylated hydroxyanisole showed the expression of the neuronal cell-specific protein marker, beta-tubulin III. The estrogen treatment increased the proportion of neurons and neurite branching but reduced the mean neurite length. The relative expression of neurotropic factors such as brain-derived neurotropic factor, glial cell derived neurotropic factor, nerve growth factor, neurotrophin-3, and growth-associated protein 43 were higher in the estrogen-treated group than in the nontreated and estrogen receptor antagonist (ICI-182,780)-treated groups. These results suggest that estrogen stimulates the differentiation of neurons derived from human umbilical cord blood mesenchymal stem cells through the gene expression of neurotrophic factors.     

大鼠脐带源间充质干细胞的分离及生物学性状**☆

背景：关于大鼠骨髓来源的间充质干细胞用于移植免疫耐受及进行组织修复的研究很多,但尚无脐带来源间充质干细胞的相关研究。 目的：建立从大鼠脐带分离间充质干细胞的方法,并观察其生物学性状。 方法：大鼠脐带经酶消化和组织块培养两种方法进行分离培养,于DMEM-LG培养基中培养,倒置显微镜观察细胞形态,细胞计数绘制生长曲线,流式细胞仪测定细胞周期及细胞表型,免疫组织化学染色检测其体外诱导成脂肪和成骨分化的能力。 结果与结论：两种方法均能成功地从大鼠脐带中获得大量的间充质干细胞：原代培养显示,胶原酶消化法比组织块培养法的效率更高,大约10 d就可以进行传代,而组织块培养法要14 d才能传代;传代扩增两者之间没有差别。免疫表型分析显示,大鼠脐带源细胞表达黏附分子和基质细胞标记CD90、CD106,不表达造血细胞标记CD34、CD45。体外诱导实验证实,大鼠脐带间充质干细胞具有成脂肪和成骨分化的能力。     

5-氮杂胞苷诱导人脐带间充质干细胞向心肌样细胞的分化☆

背景：5-氮杂胞苷能诱导人脐带间充质干细胞分化为心肌细胞。 目的：以5-氮杂胞苷诱导人脐带间充质干细胞分化为心肌细胞。 方法：采用贴壁培养法分离、纯化人脐带间充质干细胞,以5-氮杂胞苷诱导第3代人脐带间充质干细胞分化为心肌样细胞。 结果与结论：诱导前人脐带间充质干细胞呈典型的梭形;诱导后一二周细胞体积变大,三四周后相邻细胞间胞膜有接触,逐渐相连呈肌管状,细胞胞质内可见细丝样结构。诱导4周后免疫组织化学鉴定人脐带间充质干细胞cTnI表达阳性,未诱导细胞cTnI表达阴性;诱导组Nkx2.5、GATA 4 mRNA表达水平较未诱导组显著增加(P < 0.05)。提示5-氮杂胞苷可能通过调控GATA4、Nkx2.5基因的表达促进人脐带间充质干细胞分化为心肌样细胞,并促进其成熟。     

人脐带间充质干细胞向神经细胞分化过程中ILK的表达变化及意义

目的 研究在人脐带间充质干细胞(hUCMSC)向神经干细胞样细胞(hucNSC)、神经细胞(Nc)诱导分化中整合素连接激酶(ILK)的表达变化及意义.方法 将体外培养、传至第3代的hUCMSC,用无血清培养基加入bFGF、EGF和B27预诱导分化为hucNSC,继之将其用BHA、弗司扣林等向神经细胞定向诱导分化,并用AF488分别标记hUCMSC、hucNSC、NC细胞骨架变化过程加以证实,免疫组化及RT-PCR检测ILK在hUCMSC、hucNSC、NC中的表达,并用实时定量PCR加以定量分析.结果 hUCMSC被诱导后首先聚集成细胞球样悬浮生长,表达nestin、CD133,ILK表达明显增强;再被诱导后表达NSE、TH,GFAP,并持续表达ILK.hUCMSC细胞骨架呈丝状规律排列,hucNSC时则成巢状,定向诱导后的神经细胞骨架转变成多突起的树枝状.实时定量PCR检测ILK在hUCMSC中微量表达,hucNSC中表达明显上调,是hUCMSC表达水平的12倍;在NC中ILK表达较hucNSC降低,但仍高于hUCMSC 8.6倍(P＜0.05).结论 人脐带间充质干细胞向神经干细胞样细胞、神经细胞诱导分化及细胞形态重塑中ILK可能发挥重要作用.     

人脐带间充质干细胞复合聚左旋乳酸多孔支架材料异位成骨的实验研究

摘要 背景：聚左旋乳酸材料有良好的支撑作用,具有三维模板作用,为细胞黏附、增殖和分化提供场所。 目的：以人脐带间充质干细胞作为种子细胞、多孔聚左旋乳酸作为支架材料构建组织工程化骨异位成骨的可行性及效果。 方法：制备聚左旋乳酸多孔支架材料。用酶消化法分离培养人脐带间充质干细胞,传代培养、鉴定及诱导成骨,ALP染色检测骨向分化。将人脐带间充质干细胞与聚左旋乳酸材料复合培养,MTT及扫描电镜检测细胞增殖和细胞材料复合情况,应用矿化诱导7 d的细胞材料复合物植入兔大腿肌袋模型观察组织工程骨的异位成骨能力。4周后应用组织学观察新骨的形成情况。 结果与结论：与聚左旋乳酸多孔支架材料复合的人脐带间充质干细胞生长良好,细胞增殖未受影响,扫描电镜示细胞在支架材料上吸附、生长良好。体外对人脐带间充质干细胞骨向诱导后ALP染色阳性。矿化诱导的人脐带间充质干细胞复合聚左旋乳酸材料植入动物4周时,形成明显的块状组织,质地坚硬。组织学检查见新形成的组织有成骨细胞及其周围有血管长入。提示聚左旋乳酸多孔材料对种子细胞人脐带间充质干细胞的增殖无影响;人脐带间充质干细胞细胞与聚左旋乳酸多孔材料复合体可在异位形成骨组织。 关键词：人脐带间充质干细胞;聚乳酸;生物相容性;异位成骨;兔 doi:10.3969/j.issn.1673-8225.2011.12.008     

Therapeutic effect of human umbilical cord mesenchymal stem cells on neonatal rat hypoxic–ischemic encephalopathy

The therapeutic potential of umbilical cord blood mesenchymal stem cells has been studied in several diseases. However, the possibility that human umbilical cord Wharton's jelly‐derived mesenchymal stem cells (hUCMSCs) can be used to treat neonatal hypoxic–ischemic encephalopathy (HIE) has not yet been investigated. This study focuses on the potential therapeutic effect of hUCMSC transplantation in a rat model of HIE. Dermal fibroblasts served as cell controls. HIE was induced in neonatal rats aged 7 days. hUCMSCs labeled with Dil were then transplanted into the models 24 hr or 72 hr post‐HIE through the peritoneal cavity or the jugular vein. Behavioral testing revealed that hUCMSC transplantation but not the dermal fibroblast improved significantly the locomotor function vs. vehicle controls. Animals receiving cell grafts 24 hr after surgery showed a more significant improvement than at 72 hr. More hUCMSCs homed to the ischemic frontal cortex following intravenous administration than after intraperitoneal injection. Differentiation of engrafted cells into neurons was observed in and around the infarct region. Gliosis in ischemic regions was significantly reduced after hUCMSC transplantation. Administration of ganglioside (GM1) enhanced the behavioral recovery on the base of hUCMSC treatment. These results demonstrate that intravenous transplantation of hUCMSCs at an early stage after HIE can improve the behavior of hypoxic–ischemic rats and decrease gliosis. Ganglioside treatment further enhanced the recovery of neurological function following hUCMSC transplantation. © 2013 Wiley Periodicals, Inc.     

Brain-derived neurotrophic factor stimulates the neural differentiation of human umbilical cord blood-derived mesenchymal stem cells and survival of differentiated cells through MAPK/ERK and PI3K/Akt-dependent signaling pathways

Brain-derived neurotrophic factor (BDNF) plays an important role in the differentiation, development, and survival of neural stem cells. In this study, we analyzed its effects on the stimulation of human umbilical cord blood-derived mesenchymal stem cells in terms of their potential to differentiate into neuron-like cells, their survival characteristics, and the molecular mechanisms involved. The treatment of cells with neural induction medium (NIM) and BDNF generated more cells that were neuron-like and produced stronger expression of neural-lineage markers than cells treated with NIM and without BDNF. Raf-1 and ERK phosphorylation and p35 expression levels increased significantly in cells treated with both NIM and BDNF. This treatment also effectively blocked cell death following neural induction and increased Akt phosphorylation and Bcl2 expression compared with cells treated with NIM without BDNF. Inhibition of ERKs inhibited the BDNF-stimulated up-regulation of p35 and Bcl2. In addition, the inhibition of PI3K abrogated Akt phosphorylation and Bcl2 expression, but not p35 expression. Thus, MAPK/ERK-dependent p35 up-regulation and MAPK/ERK-dependent and PI3K/Akt-dependent Bcl2 up-regulation contribute to BDNF-stimulated neural differentiation and to the survival of differentiated cells.     

Mesenchymal stromal cell therapy for damaged retinal ganglion cells,is gold all that glitters?

Mesenchymal stromal cells are an excellent source of stem cells because they are isolated from adult tissues or perinatal derivatives, avoiding the ethical concerns that encumber embryonic stem cells. In preclinical models, it has been shown that mesenchymal stromal cells have neuroprotective and immunomodulatory properties, both of which are ideal for central nervous system treatment and repair. Here we will review the current literature on mesenchymal stromal cells, focusing on bone marrow mesenchymal stromal cells, adipose-derived mesenchymal stromal cells and mesenchymal stromal cells from the umbilical cord stroma, i.e.,Wharton's jelly mesenchymal stromal cells. Finally, we will discuss the use of these cells to alleviate retinal ganglion cell degeneration following axonal trauma.     

Differentiation of Wharton's jelly mesenchymal stem cells into neurons in alginate scaffold

Alginate scaffold has been considered as an appropriate biomaterial for promoting the differentiation of embryonic stem cells toward neuronal cell lineage. We hypothesized that alginate scaffold is suitable for culturing Wharton's jelly mesenchymal stem cells(WJMSCs) and can promote the differentiation of WJMSCs into neuron-like cells. In this study, we cultured WJMSCs in a three-dimensional scaffold fabricated by 0.25% alginate and 50 m M Ca Cl2 in the presence of neurogenic medium containing 10 μM retinoic acid and 20 ng/m L basic fibroblast growth factor. These cells were also cultured in conventional two-dimensional culture condition in the presence of neurogenic medium as controls. After 10 days, immunofluorescence staining was performed for detecting β-tubulin(marker for WJMSCs-differentiated neuron) and CD271(motor neuron marker). β-Tubulin and CD271 expression levels were significantly greater in the WJMSCs cultured in the three-dimensional alginate scaffold than in the conventional two-dimensional culture condition. These findings suggest that three-dimensional alginate scaffold cell culture system can induce neuronal differentiation of WJMSCs effectively.