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.     

脐血间充质干细胞的分离培养及生物学特性

背景：脐血富含干细胞,刺激后进入细胞周期的速度以及自泌生长因子的能力均强于骨髓及外周血干细胞。 目的：建立一种分离纯化、培养扩增脐血间充质干细胞的方法,并观察体外培养脐血间充质干细胞的生物学特性。 方法：密度梯度离心,贴壁培养和消化时间控制相结合,分离纯化脐血间充质干细胞。观察细胞形态,绘制细胞生长曲线,应用流式细胞仪测定细胞周期,以免疫组织化学法(SP法)测定CD29,CD44,CD34。采用体积分数20%马血清诱导脐血间充质干细胞分化为脂肪细胞,以油红O染色鉴定;0.1 μmol/L地塞米松,10 mmol/L β-甘油磷酸钠和50 μmol/L抗坏血酸诱导脐血间充质干细胞分化为成骨细胞,以碱性磷酸酶染色鉴定。 结果与结论：分离获得了高纯度贴壁生长的间充质干细胞,间充质干细胞呈梭形,细胞传代稳定,在体外连续传代培养9代,未发生形态学改变,无衰老征象。第3代间充质干细胞体外可以分化为脂肪细胞和成骨细胞。提示采用淋巴细胞分离液密度梯度离心,贴壁培养和消化时间控制相结合,可以获得纯度较高的脐血间充质干细胞,脐血间充质干细胞体外增殖和传代能力强。     

人脐带源间充质干细胞体内外移植的免疫学特征

背景：部分体外实验证实人脐带源间充质干细胞具有同种异体的免疫耐受特性,然而对其体内研究尚处于异种异体之间,且结果及机制缺少统一性。 目的：培养人脐带源间充质干细胞,通过体内外试验分析其移植免疫学特性。 方法：应用组织块贴壁法提取人脐带源间充质干细胞,通过体外淋巴细胞混合反应检测其同种异体免疫耐受作用;应用流式细胞仪检测体内行人脐带源间充质干细胞移植前后患者血液中CD4、CD8浓度及比值变化,并通过ELISA方法对比体外淋巴细胞混合培养前后血液、培养上清及体内移植前后患者血液中白细胞介素2,10、γ-干扰素的浓度变化。 结果与结论：体内外实验中,混合淋巴细胞反应前后血浆及细胞上清中的细胞因子浓度变化呈相似趋势：白细胞介素10较反应前上升(P < 0.05),γ-干扰素较反应前下降(P < 0.05)。人脐带源间充质干细胞移植后患者T细胞亚群中CD4⁺/CD8⁺比值较移植前轻度下降。说明人脐带源间充质干细胞具有同种异体免疫耐受及免疫调节作用。     

全骨髓贴壁接触培养SD大鼠骨髓间充质干细胞

背景：体外分离培养出生长状态好、高纯度、增殖能力强和数量充足的大鼠骨髓间充质干细胞,是将其作为种子细胞用于组织和细胞移植的重要前提。 目的：建立简便、快速、有效的SD大鼠骨髓间充质干细胞体外分离培养方法,并观察其生物学特性。 方法：采用全骨髓法将SD大鼠双侧股骨和胫骨骨髓细胞进行体外分离培养,贴壁接种法进行细胞纯化、传代。观察细胞生长形态及特征,绘制细胞生长曲线,检测细胞表面标记物,采用体外诱导剂诱导细胞分别向成骨、成软骨、成脂方向分化。 结果与结论：全骨髓贴壁接种法分离培养的骨髓间充质干细胞生长旺盛、纯度高,细胞生长形态呈长梭形,极性排列,细胞生长呈S形生长曲线,群体倍增时间为29 h,细胞在连续传10代后仍具有较强的增殖能力。第3代骨髓间充质干细胞的表面标记物CD44、CD29、CD90均呈阳性表达,CD45、CD34、CD11b则呈阴性表达。第3代骨髓间充质干细胞分别经成骨、成软骨、成脂诱导剂诱导后,茜素红染色、碱性磷酸酶染色、von-kossa矿化结节染色、甲苯胺蓝染色和油红O染色均呈阳性。结果验证全骨髓贴壁接种法是一种简便可靠的体外分离培养方法,能获得纯度较高的骨髓间充质干细胞,经实验鉴定第3代骨髓间充质干细胞生物活性最佳,且具有多向诱导分化能力,适合作为后续实验的种子细胞。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

人脐血间充质干细胞对T淋巴细胞旁分泌的免疫调节作用

背景：相关研究表明脐血间充质干细胞具有一定的免疫调节作用,但具体机制不详。 目的：观察脐血源间充质干细胞通过旁分泌机制对T淋巴细胞增殖的影响。 方法：分离正常分娩产妇脐血间充质干细胞和健康志愿者外周血T淋巴细胞,按不同比例建立脐血间充质干细胞与T淋巴细胞非接触共培养体系,以单独培养T淋巴细胞作为对照组。 结果与结论：脐血间充质干细胞形态学呈现成纤维梭型细胞样,呈旋涡状团集生长。流式细胞仪检测脐血间充质干细胞表面标记物：CD29(+),CD44(+),CD34(-),CD45(-),HLA-DR(-);与对照组相比,共培养组可明显抑制植物血凝素刺激T淋巴细胞的增殖作用(P < 0.05),且呈剂量依赖性;ElISA法检测共培养组分泌的白细胞介素10水平较对照组明显升高(P < 0.05);中和试验后脐血间充质干细胞对T淋巴细胞增殖的抑制作用明显减弱。结果说明脐血间充质干细胞可明显抑制异体外周血T淋巴细胞的增殖,可能是通过旁分泌白细胞介素10达到负向免疫调节作用。     

人脐血间充质干细胞培养及其生物学特性的研究

目的建立人脐血间充质干细胞体外分离培养的最佳条件,并观察其生物学特性。方法在无菌条件下抽取人脐血,用密度梯度离心的方法获得脐血单个核细胞,接种含10%胎牛血清的IMDM培养基中。对单个核细胞行贴壁培养后,进行细胞形态学观察,细胞生长、细胞周期分析及细胞凋亡检测,免疫细胞化学鉴定。结果采用Percoll(1.073g/ml)分离的脐血间充质干细胞(mesenchymal stem cells,MSCs)大小较为均匀,呈梭形或星形的上皮样细胞,传代培养后的细胞体积较大,成纤维样细胞逐渐增多。细胞生长曲线测定表明接种后第5d细胞进入指数增生期,至第9d进入平台期;流式细胞术证明G2+S期细胞为14.8%;免疫细胞化学染色结果表明42.0%细胞为CD45阳性。结论体外分离培养脐血间充质干细胞生长稳定,可作为组织工程的种子细胞。     

人脐血间充质干细胞的体外成骨

背景：用免疫细胞阴性筛选法可以排除造血干细胞对于间充质干细胞生长的影响,较快的获得具有表达间充质干细胞的细胞群。 目的：探讨人脐静脉血间充质干细胞向成骨样细胞分化的能力。 方法：用免疫磁珠阳性筛选法分离脐血间充质干细胞后进行培养。取P2代细胞行成骨诱导分化。 结果与结论：人脐血间充质干细胞贴壁生长,长梭形,3周长满瓶底,传代后细胞增殖迅速。细胞表型为高表达CD44⁺,CD29⁺和CD166⁺。在成骨诱导后碱性磷酸酶染色阳性,Von-Kossa染色提示钙化结节形成。提示脐血间充质干细胞能够在体外分化为成骨样细胞。     

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。     

脐带间充质干细胞体外对脐带血CD4+ T 淋巴细胞免疫调节作用的研究

目的:研究脐带间充质干细胞(UCMSCs)在体外对异源脐血CD4+ T 淋巴细胞增殖、凋亡及向CD4+ CD25+ 调节性T 细胞(Treg)分化的免疫调控作用。方法:建立不同比例UCMSCs 与植物血凝素(PHA)活化的脐血CD4+ T 淋巴细胞共培养,或与Transwell 共培养体系,检测CD4+ T 淋巴细胞增殖情况、CD4+ CD25+ / CD4+ 比率的变化及调节性T 淋巴细胞标志基因Foxp3 相对表达量的变化。同时,建立UCMSCs 与地塞米松(DXM)刺激的脐血CD4+ T 淋巴细胞共培养,或与Transwell 共培养体系,检测CD4+ T 淋巴细胞凋亡情况。结果:PHA 活化的脐血CD4+ T 淋巴细胞在与UCMSCs 共培养3 d 后,较无UCMSCs对照组相比,细胞数量明显减少(P<0. 05)且CD4+ CD25+ / CD4+ T 淋巴细胞的比率及Foxp3 的相对表达量显著增加(P<0. 01),并随UCMSCs 数量增加,作用增强(P<0. 05)。DXM 诱导的脐血CD4+ T 淋巴细胞与UCMSCs 共培养7 d 后,细胞凋亡比率较无UCMSCs 对照组显著降低(P<0. 01)。上述效应在Transwell 共培养中部分减弱但无法消除。结论:UCMSCs 对脐血CD4+ T细胞介导的免疫反应具有负调节作用,其作用主要表现在对细胞增殖能力和分化的调控而不是促进凋亡。     

间充质干细胞的细胞表型及免疫学研究进展

间充质干细胞具有多分化潜能,参与构成骨髓的微环境,分泌大量细胞因子支持造血。最近的研究显示间充质干细胞免疫表型呈现动态的表达;同种异体细胞移植免疫排斥由于移植抗原差异而引起,但同种异体间充质干细胞却具有免疫抑制作用。综述了其可能的机制及作为组织工程种子细胞的间充质干细胞具有独特的生物学特性。     

Umbilical cord mesenchymal stem cells: adjuvants for human cell transplantation.

The Wharton's jelly of the umbilical cord is rich in mesenchymal stem cells (UC-MSCs) that fulfill the criteria for MSCs. Here we describe a novel, simple method of obtaining and cryopreserving UC-MSCs by extracting the Wharton's jelly from a small piece of cord, followed by mincing the tissue and cryopreserving it in autologous cord plasma to prevent exposure to allogeneic or animal serum. This direct freezing of cord microparticles without previous culture expansion allows the processing and freezing of umbilical cord blood (UCB) and UC-MSCs from the same individual on the same day on arrival in the laboratory. UC-MSCs produce significant concentrations of hematopoietic growth factors in culture and augment hematopoietic colony formation when co-cultured with UCB mononuclear cells. Mice undergoing transplantation with limited numbers of human UCB cells or CD34(+) selected cells demonstrated augmented engraftment when UC-MSCs were co-transplanted. We also explored whether UC-MSCs could be further manipulated by transfection with plasmid-based vectors. Electroporation was used to introduce cDNA and mRNA constructs for GFP into the UC-MSCs. Transfection efficiency was 31% for cDNA and 90% for mRNA. These data show that UC-MSCs represent a reliable, easily accessible, noncontroversial source of MSCs. They can be prepared and cryopreserved under good manufacturing practices (GMP) conditions and are able to enhance human hematopoietic engraftment in SCID mice. Considering their cytokine production and their ability to be easily transfected with plasmid-based vectors, these cells should have broad applicability in human cell-based therapies.     

人脐血来源MSCs的主要生物学特性的研究

目的：探讨人脐血间充质干细胞（MSCs）分离、纯化、扩增、表面标志、免疫表型及其造血生长因子（HGFs）分泌等生物学特性方法：(1) Ficoll法分离、纯化人脐血、成人骨髓和胎儿骨髓MSCs，动态观察不同来源MSCs的生长状况。(2) 流式细胞仪检测脐血和骨髓MSCs表面CD34、CD45、CD14、CD29、CD44、CD105、CD166、CD80、CD86、CD40和CD40L的表达。(3) ELISA法检测脐血和骨髓MSCs培养上清中SCF、TPO、FLT-3L和IL-6的分泌水平。结果：(1) 所有骨髓标本中均可分离纯化出MSCs，而15份脐血中仅4份分离纯化出MSCs，脐血MSCs和骨髓MSCs的细胞形态无明显差异,脐血MSCs原代培养所需要的单个核细胞（MNC）量为骨髓MSCs的3倍，且其原代培养的增殖速度较慢，但脐血MSCs传代培养的增殖速度和骨髓相似。(2) 脐血MSCs和骨髓MSCs表面标志无差异，均不表达造血细胞表面标志以及与免疫识别有关的表面抗原。(3) 脐血和骨髓MSCs分泌SCF、TPO、FLT-3L和IL-6的水平相似。结论： (1)脐血和骨髓同样可以分离、纯化MSCs，但脐血中MSCs的含量少，且大部分脐血中不含MSCs。(2)纯化的脐血MSCs扩增能力、表面标志、免疫学表型及HGFs分泌水平和骨髓MSCs相似。     

Expansion of LTC-ICs and maintenance of p21 and BCL-2 expression in cord blood CD34(+)/CD38(-) early progenitors cultured over human MSCs as a feeder layer

Allogeneic transplantation with umbilical cord blood (UCB) is limited in adult recipients by a low CD34(+) cell dose. Clinical trials incorporating cytokine-based UCB in vitro expansion have not demonstrated significant shortening of hematologic recovery despite substantial increases in CD34(+) cell dose, suggesting loss of stem cell function. To sustain stem cell function during cytokine-based in vitro expansion, a feeder layer of human mesenchymal stem cells (MSCs) was incorporated in an attempt to mimic the stem cell niche in the marrow microenvironment. UCB expansion on MSCs resulted in a 7.7-fold increase in total LTC-IC output and a 3.8-fold increase of total early CD34(+) progenitors (CD38(-)/HLA-DR(-)). Importantly, early CD34(+)/CD38(-)/HLA-DR(-) progenitors from cultures expanded on MSCs demonstrated higher cytoplasmic expression of the cell-cycle inhibitor, p21(cip1/waf1), and the antiapoptotic protein, BCL-2, compared with UCB expanded in cytokines alone, suggesting improved maintenance of stem cell function in the presence of MSCs. Moreover, the presence of MSCs did not elicit UCB lymphocyte activation. Taken together, these results strongly suggest that the addition of MSCs as a feeder layer provides improved conditions for expansion of early UCB CD34(+)/CD38(-)/HLA-DR(-) hematopoietic progenitors and may serve to inhibit their differentiation and rates of apoptosis during short-term in vitro expansion.     

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。     

Prevalence of intracellular galectin-1-expressing lymphocytes in umbilical cord blood in comparison with adult peripheral blood

Umbilical cord blood (UCB) is a promising alternative for the treatment of hematological malignancies. The lower immune reactivity of UCB lymphocytes is a well-known phenomenon; however, immune tolerance mechanisms are not fully elucidated. Galectin-1 has strong immunosuppressive properties and plays a key role in the regulation of immune reactivity. We aimed to determine the properties of intracellular galectin-1 (Gal-1)-producing cells within CD3, CD4, CD8, regulatory T (Treg), and natural killer (NK) cells in UCB compared to adult peripheral blood (APB). We took peripheral blood samples from 22 healthy adults and cord blood samples from 19 healthy, term neonates. Intracellular Gal-1 expression was determined by flow cytometry in the above subsets. Furthermore, we assessed the prevalence of naive and memory T cells that play a role in the regulation of immune reactivity. We also performed functional analyses to assess the effect of exogenous Gal-1 on the rate of proliferation of T lymphocytes isolated from APB and UCB. The prevalence of intracellular Gal-1-expressing CD3, CD4, CD8, Treg and NK lymphocytes was lower in UCB than in APB. However, their capability to produce Gal-1 reaches the level seen in adults. The prevalence of naive cells was higher, whereas that of central and effector memory T cells was lower in UCB compared with APB. Lower Gal-1-producing cell proportion might be due to the naivety of neonatal lymphocytes, as indicated by the positive correlation detected between the number of CD3 lymphocytes expressing intracellular Gal-1 and the prevalence of memory T cells. The intracellular expression of Gal-1 may be down-regulated in neonatal lymphocytes due to the already reduced immune reactivity of UCB. In contrast with previous findings, our results indicate that the administration of exogenous Gal-1 failed to decrease the rate of proliferation in T lymphocytes isolated from either APB or UCB. This suggests that Gal-1-expressing lymphocytes are unlikely to play a major role in mitigating the immune reactivity of UCB.     

脐带间充质干细胞促进骨愈合的体外实验及临床应用1例

背景：华通胶来源脐带间充质干细胞比成人间充质干细胞更原始,研究表明其端粒酶活性更高、培养倍增时间更短、分化的细胞谱系更广。 目的：观察脐带间充质干细胞在体外分化为成骨细胞的能力及治疗骨折不愈合的效果。 方法：从脐带Wharton胶获取细胞培养、扩增,取传代细胞行免疫表型测定和成骨细胞诱导分化,并以脐带间充质细胞移植治疗1例骨折感染外露后长期不愈病例。 结果与结论：培养细胞形态类成纤维细胞,可长期稳定培养,传代细胞表达间充质干细胞免疫表型,成骨诱导分化的细胞茜素红染色胞浆中有大量的钙沉积,Von Kossa染色有钙结节形成。患者采用脐带间充质干细胞混悬液外用4次,肉芽组织迅速增生填满窦道并上皮化,12 d创面愈合。说明,脐带间充质干细胞具有高度自我更新能力和分化潜能,能够向成骨细胞分化,将其移植治疗骨不连可以显著改善局部微环境。     

Primary cells as feeder cells for coculture expansion of human hematopoietic stem cells from umbilical cord blood--a comparative study

Although umbilical cord blood (UCB) has been widely accepted as an alternative source of hematopoietic stem cells (HSC) for transplantation, its use in adults is restricted because of low absolute HSC numbers. To overcome this obstacle, expansion of HSC in coculture with feeder cells is a promising possibility. In this study, we compared the potential of three human primary cell types, namely, mesenchymal stem cells (MSC), human umbilical cord vein endothelial cells (HUVEC), and Wharton's jelly cells (WJC), for use as feeder cells in a potentially clinically applicable coculture system. In first experiments, we evaluated procedures needed to obtain feeder cells, the possibility to separate them from cells derived from CD34(+) cells after coculture, their ability to activate allogeneic T cells, and their survival in CD34(+)-adapted medium. Finally, we compared their support for UCB-derived CD34(+) expansion. MSC and WJC were superior to HUVEC in terms of ease and reliability of isolation procedures needed. None of the potential feeder cells expressed CD34 or CD45, thus providing markers for cell sorting after coculture. Other markers (CD31, CD90, CD105, CD166) were expressed differently on feeder cell types. While MSC in higher concentrations did not activate allogeneic T cells, those were stimulated by lower concentrations of MSC as shown by CD25, CD69, and CD71 expression. In contrast, HUVEC and WJC were proven to activate T cells at all ratios tested. Feeder cells survived a 7-day culture in CD34(+)-adapted medium. In cocultures of UCB CD34(+)cells with primary feeder cells, mononuclear cell expansion was 30- to 60-fold, colony-forming cell expansion 20- to 40-fold, and cobblestone area-forming cell expansion 10- to 50-fold. We conclude that after a careful further evaluation especially of their immunological properties, all three primary cell types might possibly be suitable for use in a potentially clinically applicable system for expansion from UCB CD34(+)cells, with WJC being best choice and MSC still superior to HUVEC.