脐带血免疫学特性的研究进展

脐带血干/祖细胞移植在造血和免疫系统的恢复与重建中具有重要的临床应用前景.脐带血中含有丰富的造血和免疫活性物质,脐带血免疫细胞的功能特性与脐带血细胞的成功移植和低GVHD的发生密切相关.此外,脐带血的单核细胞、树突状细胞和NK细胞还在血液系统及其他肿瘤的免疫治疗中有研究价值.     

广州脐血库造血干细胞保存及临床应用

目的 分析广州脐血库造血干细胞保存及临床应用状况.方法 建立脐带血造血干细胞库,按照良好作业规范(GMP)及标准操作常规(SOP)进行供者合格性筛选、脐带血采集、处理、检测、冷冻保存、检疫和发放.分析1998年6月至2008年12月广州脐血库脐带血保存、发放情况及临床移植效果.结果 1998年6月至2008年12月,共采集脐带血10 017份,合格并保存4619份(46.1%),因各种原因废弃5398份(53.9%).4619份合格脐带血的采集体积中位数为92.2ml(60.0～227.7ml),细胞活率中位数为99.0%(90.0%～100.0%),分离后总有核细胞数中位数为1.1×109(0.4×109～9.3×109).4186份脐带血CD34+细胞数中位数为4.1×106(0.3×106～131.6×106).4510份脐带血粒-单核系祖细胞(CFU-GM)的中位数为7.7×105(0.0～135.8×105);爆式红系集落形成单位(BFU-E)的中位数为7.7×105(0.0～88.9×105);粒红巨核巨噬系集落形成单位(CFU-GEMM)的中位数为0.1×105(0.0～18.6×105).至2008年12月,已提供229份脐带血用于治疗187例患者,包括128例(68.4%)儿童,59例(31.6%)成人,其中86例儿童及38例成人获得植入,中性粒细胞植入时间中位数分别为16 d(9～44 d)及20 d(8～42d).结论 建立严格的操作常规和完善的管理制度,是脐带血库进行干细胞冷冻保存及提供合格干细胞产品用于临床的先决条件.     

脐带血造血干细胞的分离和冷冻保存研究

目的探讨为临床移植有效地分离和冷冻保存无关供者脐带血中的造血干细胞的方法。方法将由普通或改进的两种不同采集袋采集的脐带血,用两步离心法分离、浓缩脐带血中的有核细胞,用BioArchive System(生物档案系统)或常规的程控降温系统将之冷冻,保存在-196℃液氮中。用流式细胞术和细胞培养法检测脐带血中的CD34+细胞和造血祖细胞含量。结果脐带血用改进的采集袋分离后,有核细胞和红细胞的回收率分别为86.4%±4.6%和44.2%±9.6%,而普通采集袋的回收率为78.4%±7.9%和49.8%±11.7%;将富含有核细胞悬液的体积浓缩到20 ml时,有核细胞和红细胞的回收率分别为74.62±9.3%和34.9%±19.1%,浓缩体积为32 ml回收率为86.4%±4.6%和45.1%±7.8%/但两者的CD34+细胞和造血祖细胞的回收率无统计学意义;冷冻脐带血融化后有核细胞、CD34+细胞和CFU-C回收率分别为84.2%±10.1%、96.0%±21.8%和115.1%±23.3%。苔盼蓝拒染率93.8%±4.4%。结论改进的采集袋能够明显提高有核细胞回收率。采用两步离心法和两种冻存方法能够有效地富集和冻存脐带血中的造血干细胞。     

小儿外周血造血干/祖细胞采集效果和安全性的研究

目的探讨小儿外周血造血干/祖细胞采集的效果和安全性。方法32名供者经粒细胞集落刺激因子（G-CSF）动员后,应用血细胞分离机进行外周血干/祖细胞采集。循环血量2～6 L。采集中,监测病人的血压、心率、呼吸、MNC（单个核细胞）、WBC、RBC、Hb、Hct和Plt及血清Ca^2＋浓度的变化。采集的MNC液用CD34单抗标记后检测CD34^＋细胞数,并同时作CFU-GM集落培养。结果32例共进行了89次干/祖细胞采集,机器平均每次循环血量2.5个血容量。MNC采集效率达（64.78±3.23）%,每次采得MNC液60ml,获得MNC为（3.1±0.6）×10^8/kg;CD34＋为（2.8±0.6）×10^6/kg及CFU-GM（2.6±0.5）×10^5/kg。术中供者无任何不良反应。采集前后血压、心率、呼吸、RBC、Hb、Hct和血清Ca^2＋浓度无明显变化（P〉0.05）,但Plt数从采集前的159.63×10^9/L下降到采集后的112.78×10^9/L,下降幅度达29.35%。结论采用CS-3000PLUS血细胞分离机采集小儿外周血造血干/祖细胞是一种有效和安全的方法,供者仅需2～3次采集就能获得异体外周血造血干/祖细胞移植所需的干/祖细胞数量。     

脐带血AC133+细胞体外扩增及生物学特性的研究

目的研究脐带血穴UCB雪AC133 细胞体外扩增及其生物学特性,动态观察AC133 细胞的免疫表型变化,以了解AC133 抗原与CD34抗原的关系。方法将从新鲜UCB标本中纯化的AC133 细胞接种于无血清无基质的悬浮体系,分别于培养0、7、10、14天检测扩增潜能、免疫表型和集落形成等指标。结果①自早期的AC133 CD34-、AC133 CD34 、CFC-HPP、CFU-GEMM、AC133 及CD34 细胞群至各系定向祖细胞等各阶段造血干/祖细胞穴HSPC雪均得到持续显著的扩增;②AC133 和CD34 细胞的比例随培养时间的延长而迅速降低,AC133 细胞在CD34 细胞中的比例亦明显下降穴从99%降至50%雪,但同一时点AC133/CD34亚群比例均呈现出AC133 CD34-相似文献   

脐带血造血干祖细胞移植的基础

1 什么是造血干祖细胞最佳的移植物造血干祖细胞移植(HSPCT)用于治疗造血干祖细胞缺陷性血液病、先天性免疫缺损、先天性贫血、各类自身免疫病等,也用于实体瘤的治疗,是一种重要的生物治疗或细胞治疗。实际上,不论来自骨髓、脐带血或动员的外周血,移植物中含的不仅是造血干细胞,还包括更多的早期造血祖细胞,所谓“造血干细胞移植(HSCT)”实际上是造血干祖细胞移植(HSPCT)。这是当前对“造血干细胞移植”含义崭新的理解。CD34 细胞中90%以上是早期和晚期祖细胞,干细胞只是很小一部分。永久重建造血所需要的造血干细胞为数很少…     

黑龙江省3866名健康儿童静脉血细胞参数参考范围调查

目的调查分析黑龙江省健康儿童静脉全血细胞8个参数的水平,建立各参数的儿童参考范围。方法 随机抽取黑龙江省部分地区8～16岁健康儿童3 866人(男性1 837人,女性2 029人),采集受试者清晨空腹静脉血,用Sysmex XT-1800i全血细胞分析仪进行检测。采用SPSS 15.0软件分析比较各参数在民族、地区及年龄间的差异。结果 黑龙江省健康儿童静脉血细胞参数均值(参考范围)中白细胞计数为6.9(3.9～9.9)×109/L,红细胞计数男性为5.0(4.2～5.8)×1012/L,女性为4.6(4.0～5.2)×1012/L,血红蛋白浓度男性为146(124～168)g/L,女性为135(117～153)g/L,血细胞比容男性为43.9%(37.5%～50.5%),女性为41.2%(36.4%～46.0%),红细胞平均体积为88(80～96)fl,红细胞平均血红蛋白含量为29(25～33)pg,红细胞平均血红蛋白浓度为329(311～347)g/L,血小板计数为277(161～393)×109/L。汉族、朝鲜族健康儿童的WBC、HGB、MCH、MCHC及PLT5项参数存在显著差异(P<0.05);黑...     

造血干/祖细胞的体外扩增培养研究

利用旋转壁式生物反应器(Rotating wall vessel,RWV)体外培养脐带血干细胞,使其大量扩增,以满足临床应用对造血干/祖细胞的数量与质量要求。从脐带血分离得到的单个核细胞(Mononuclear cells,MNC)在T-flask中培养24h,之后接种到RWV反应器中,培养200h。每24h细胞计数,测量培养基的pH和渗透压变化;在144h和197h测CD34 细胞含量并做CFU-GM半固体培养。有核细胞(Nucleated cells,NC)与CD34 细胞在第197h,分别扩增了435.5±87.6倍和32.7±15.6倍,CFU-GM(Colony-forming unit-granulocyte/macrophage)细胞扩增了21.7±4.9倍。整个培养过程中,RWV反应器中的pH和渗透压都保持在造血细胞最佳的扩增条件内,pH基本保持在7.2~7.4之间,渗透压基本保持在290~310mmol/kg之间。由于旋转壁式生物反应器(RWV)结构上的特殊性,可以保证细胞在悬浮流动的状态下生长,很好地模拟了脐带中的造血微环境,使脐带血造血干细胞在该反应器中短期内得到大量扩增。     

581例脐带血细胞各参数结果分析

目的了解脐带血血细胞各参数与正常成人静脉血血细胞各参数有无显著性差异.是否需要建立脐带血血常规正常参考范围.方法用美国COULTER-GENS全自动五分类血球计数仪对581例脐带血进行检测血常规和网织红各参数,并用统计学分析.结果脐带血各参数值与正常成人静脉血除血小板数量、单核细胞百分数、嗜酸性粒细胞百分数、嗜碱性粒细胞百分数无显著性差异外,各参数值有显著性差异(P＜0.01).结论脐带血应建立其本身的正常参考值,不能用成人静脉血血常规参考值代替.     

脐带血CD4~+和CD8~+ T细胞中T细胞特异转录因子Elf-1表达特点

目的:了解脐带血单个核细胞(CBMCs)及其CD4+和CD8+ T细胞亚群中转录因子Elf-1的表达特点。方法:采用SYBR GreenⅠ荧光定量PCR和相对定量分析法检测12例脐带血CBMCs、CD4+和CD8+ T细胞亚群中Elf-1基因的表达情况,以β2微球蛋白基因(β2M)作为内参照,10例健康成人作为对照,采用相对定量公式:2-△Ct×100%,计算Elf-1mRNA相对表达量。结果:脐带血和健康成人外周血单个核细胞(PBMC)、CD4+和CD8+ T细胞均表达Elf-1,具体表达量呈现明显的个体差异性。Elf-1 mRNA相对表达量在CBMCs为18.55%±2.48%(其中最高为36.22%,最低为6.45%),在脐带血CD8+ T细胞为3.52%±0.45%(其中最高为6.75%,最低为1.71%),均明显高于健康成人PBMC(9.16%±1.92%)及其CD8+ T细胞(2.02%±0.27%)(P0.01,P0.05),而脐带血CD4+T细胞Elf-1 mRNA相对表达量为3.83%±0.61%,与健康成人外周血CD4+ T细胞(2.73±0.52%)比较,无显著差异。结论:本研究率先报道脐带血T细胞亚群中Elf-1 mRNA表达特点,结果提示Elf-1基因在CBMCs及其CD8+ T细胞亚群中的高表达可能是T细胞的免疫学特点之一。     

Immunoregulatory function of mesenchymal stem cells

Mesenchymal stem cells (MSC) are a rare subset of stem cells residing in the bone marrow where they closely interact with hematopoietic stem cells and support their growth and differentiation. MSC can differentiate into multiple mesenchymal and non-mesenchymal lineages, providing a promising tool for tissue repair. In addition, MSC suppress many T cell, B cell and NK cell functions and may affect also dendritic cell activities. Due to their limited immunogenicity, MSC are poorly recognized by HLA-incompatible hosts. Based on these unique properties, MSC are currently under investigation for their possible use to treat immuno-mediated diseases. However, both their condition of immunoprivilege and their immunosuppressive function have recently been challenged when analyzed under particular experimental conditions. Thus, it is likely that MSC effects on the immune system may be deeply influenced not only by cell-to-cell interactions, but also by environmental factors shaping their phenotype and functions.     

CENTRAL TOLERANCE MECHANISMS IN CONTROL OF SUSCEPTIBILITY TO AUTOIMMUNE UVEITIC DISEASE

A family of dendritic cells has been identified in situ and in vitro by microscopy and immunolabeling. The members of this family include the dendritic cells isolated from lymphoid organs, Langerhans cells [LC] of the epidermis, veiled cells in afferent lymph, and interdigitating cells [IDC] in the T-cell areas. Some common features to all members of the family are high levels of MHC class II antigens, a lack of most B and T cell markers, and an absence or low levels of macrophage/granulocyte antigens. This review summarizes the markers of mouse dendritic cells as assessed by a panel of monoclonal antibodies, and stresses a few recent findings. 1) In spleen, there are two populations of dendritic cells. More than 75% of isolated cells are 33D1⁺, NLDC145^?, and JI1d^?, while the remainder have the reciprocal phenotype and thus share the NLDC145 antigen of IDC. Thymic dendritic cells, released by collagenase digestion, and epidermal LC also are 33DI^?, NLDC145⁺, J11d⁺. 2) When epidermal LC are placed in culture, there are changes in cell function and phenotype. There is a decrease in Fc-γ receptors and the F4/80 macrophage antigen, an increase in class I and II MHC products and p55 IL-2 receptors, and persistence of the NLDC145 IDC antigen. The cultured LC thereby resembles the IDC. 3) A new antibody N418 shows that dendritic cells express the p150/90 member of the leukocyte β₂ integrin family. Immunolabeling of tissue sections of spleen indicates that N418⁺ dendritic cells not only are present in the periarterial sheaths, the location of IDC, but also in “nests” at the periphery of the T area where 33D1 has been found. The peripheral collections interrupt the marginal zone of macrophages that separates white and red pulp, and places the dendritic cells in the path of T cells as they move through the white pulp. Therefore the members of the dendritic cell family have important markers in common, as well as differences that are associated with state of immunologic function and location.     

Activated NKT cells increase dendritic cell migration and enhance CD8+ T cell responses in the skin

Activated NKT cells produce cytokines such as IL-4 and IFN-gamma that function locally to influence the strength and functional development of antigen-specific T cells. Here we identify an alternative mechanism by which NKT cells influence the strength of T cell responses: through modulation of peripheral dendritic cell (DC) trafficking. NKT cell activation with alpha-galactosylceramide induced high systemic levels of TNF-alpha that mediated increased DC migration from skin to draining lymph nodes. This increased DC trafficking led to a threefold increase in effector T cell priming and in the immune response elicited to antigen challenge when alpha-galactosylceramide was given at the time of immunization of the skin. These studies provide important implications for the use of NKT cell activation strategies to manipulate T cell-mediated responses including responses to cutaneous tumors and graft vs. host disease.     

Influences of the pia mater on the precursors of nerve cells

Summary In the developing cerebellum of 8-day old rats surgical lesions were made. During regeneration of the cerebellum the pia mater was found to penetrate inside the neural tissue. Partially differentiated Purkinje cells and granule cells, that were in close contact with the pial cells, were found atrophied. When the profilerative cells of external granular layer came into contact with the pial cells, they were reduced to a primitive type of epitheloid cells. In this instance epithelio-mesenchymal interaction was found deleterious to the precursors of neurons. However, when the epithelioid cells were freed from the contact with the pial cells by intervening basement membrane, they differentiated into ependymal cells. Such ependymal cells gave rise to small as well as large new ventriculer structures, and structures resembling chorioid plexus.This research was supported by NIH Research Grant NS08817-03. Acknowledgements are due to Sheila Anderson for histology and to Donna Whitehurst for photographic work.     

后肾细胞微环境诱导胚胎干细胞向肾系细胞分化的实验研究

目的: 探讨胚胎后肾细胞微环境诱导胚胎干细胞(ESCs)分化为肾系细胞的作用。方法: 小鼠D3系胚胎干细胞通过悬滴法制备拟胚体(EBs),将EBs细胞与取自孕12.5 d小鼠胚胎的后肾细胞通过间接共培养以诱导其分化,即为共培养诱导组,设EBs细胞自然分化为对照组;采用免疫荧光染色法检测共培养第3、5、7 d后的EBs细胞Pax2、WT-1蛋白表达情况,通过逆转录PCR法检测诱导3 d后的EBs细胞Pax2、WT-1、Lim1、Sall1、Emx2、GDNF、Wnt4、BMP7、Nephl、Nephrin、KSP和CD24 mRNA的表达情况。结果: EBs细胞在诱导的第3 d即出现了全部肾发育相关基因的表达,其中共培养组Pax2、WT-1、Emx2、GDNF、Nephl、Nephrin、KSP和CD24的表达强于对照组;免疫荧光结果显示在诱导3 d后的EBs细胞中可观察到Pax2阳性细胞,阳性细胞数在共培养第5、7 d增多;诱导5 d后可观察到WT-1阳性细胞,对照组未见Pax2或WT-1蛋白阳性细胞出现。结论: 后肾细胞微环境可促进ESCs分化为肾系细胞。     

脂肪来源干细胞诱导分化为神经元样细胞的实验研究

目的： 研究脂肪来源干细胞（ASCs）的分离、纯化、扩增以及在体外定向分化为神经元样细胞的能力。 方法: 获取并培养正常人的ASCs，倒置显微镜下观察其形态；流式细胞仪检测其免疫表型。全反式维甲酸（ATRA）诱导ASCs在体外分化为神经元样细胞，倒置显微镜观察神经元样细胞的形态，逆转录-聚合酶链反应（RT-PCR）检测巢蛋白基因的表达；免疫组织化学染色法和Western blotting法检测神经丝蛋白（NF）和神经元烯醇化酶（NSE）的表达。 结果: ASCs呈纤维样贴壁生长，体外培养易扩增；ASCs表达相关抗原CD29和CD105，不表达CD31、CD34、CD45和HLA-DR；不同扩增代数的ASCs经诱导剂的作用可呈现典型的神经元样细胞形态，巢蛋白基因及NF、NSE均呈阳性表达。 结论: 脂肪组织中分离培养的ASCs具有体外大量扩增并保持低分化状态的特性，以及定向分化为神经元样细胞的能力, 是一种可用于神经系统疾病治疗的种子细胞。     

Accessory phenotype and function of macrophages induced by cyclic adenosine monophosphate

Mature macrophages (Mph) differentiated in culture from normal human peripheral blood monocytes (Mo) exhibit low activity as accessory cells (antigen-presenting cells) in T lymphocyte stimulation. A test system was established based on mitogenicity to quantitate the accessory activity of Mph-derived cells and to follow its changes for several days. The system used accessory cells treated with the oxidative mitogen, sodium periodate. The cells were subsequently co-cultured with pooled human lymphocytes from a cryopreserved stock. DNA synthesis in these cells was used as an indicator of accessory activity. Mph could be converted within 5-6 days into highly active accessory cells if a continuous stimulus of exogenously added dibutyryl cyclic AMP (db-cAMP) was provided. Mph treated by db-cAMP retained a high degree of HLA-DR expression but typical Mph markers such as non-specific esterase, phagocytosis, and expression of Fc-receptors were down-regulated. Acid phosphatase and myeloperoxidase underwent only slight changes, while the monocyte marker 5'-nucleotidase remained undetectable. Morphologically, the cells rounded up and developed veils and dendritiform elongations. In contrast to dendritic cells, Mph-derived accessory cells retained the CD14 antigen characteristic of monocytes and Mph. It is concluded that Mph are able to respond to exogenous stimuli and to convert into a highly active accessory cell. This contrasts to the well-known state of the 'activated Mph' with respect to markers and function. Both states appear to be antagonistically controlled by intracellular second messengers, as the accessory cell phenotype is positively correlated with intracellular cyclic AMP increase, whereas Mph activation correlates with cyclic GMP increase.     

干细胞若干定义的相关探讨

背景：近10年来干细胞研究所取得的巨大进展,不仅影响和促进了生物学及其相关基础科学,而且还在医学、药物开发、农业等许多领域得到广泛的应用,目前已成为研究的热点问题。 目的：在干细胞的定义上还存在一些需要探讨的问题,明确定义将有利于干细胞研究的快速发展。 方法：回顾干细胞的发展和概念提出,特别是通过中英文权威定义的比较,提出作者的看法。 结果与结论：干细胞的定义上还存在一些问题值得探讨,特别是一些中英文表述不同影响了理解。例如,“多能干细胞”对应译成两个单词：Pluripotent Stem Cell和Multipotent Stem Cell,然而Pluripotent和Multipotent两个单词的英文意义不同。为了学术交流和沟通,作者提出将Pluripotent Stem Cell称为“万能干细胞”,而保留Multipotent Stem Cell为“多能干细胞”的定义。以上结论供广大同仁探讨,以利于抛砖引玉。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：