造血干细胞的抗原特性

本文综述了近年来有关人和小鼠造血祖细胞各种抗原系统的特点及其鉴别方法,以及在生物学和治疗学方面的有关问题。造血祖细胞在有刺激因子存在的半固体培养中,粒-巨噬祖细胞(CFU-G,M)可形成粒细胞或巨噬细胞,或二者混合组成的细胞集落。在红细胞生成素(Ep)刺激下,红系祖细胞(BFU-E和 CFU-E)可生成红系细胞集落。小鼠多能干细胞是通过受致死剂量照射小鼠的脾脏形成     

人巨细胞病毒感染致造血祖细胞增殖抑制与更昔洛韦的影响

背景:临床研究显示,骨髓移植后人巨细胞病毒感染可阻碍血小板植入、出现表型异常的外周血白细胞,导致骨髓移植失败,这可能是由于人巨细胞病毒感染直接影响了造血祖细胞所致.目的:观察更昔洛韦对人巨细胞病毒感染所致脐血粒-巨噬系祖细胞、红系祖细胞、淋巴系祖细胞、多向造血祖细胞及巨核系祖细胞体外增殖抑制的影响及更昔洛韦对此的保护作用. 设计:对比观察性实验.单位:泸州医学院附属医院分子生物学实验室.对象:正常足月顺产新生儿脐血标本20例,每份10 mL,由泸州医学院附属医院妇产科提供,产妇对本实验知情同意.实验经医院伦理委员会批准.方法:实验于2004-06/2006-12在泸州医学院附属医院分子生物学实验室完成.采用脐血标本造血祖细胞培养技术,观察、计数100 TCID50人巨细胞病毒-AD169感染粒-巨噬系祖细胞、红系祖细胞、淋巴系祖细胞、多向造血祖细胞及巨核系祖细胞后各祖细胞集落数,记录集落维持时间.用PCR和荧光定量PCR技术检测集落细胞内人巨细胞病毒-AD169DNA.将7.5 mg/L更昔洛韦作用于人巨细胞病毒感染的造血祖细胞,再分别计集落数、集落维持时间及集落细胞内人巨细胞病毒-AD169DNA.设正常培养的造血祖细胞为空白对照组,设与含灭活性人巨细胞病毒的正常造血祖细胞培养系统为灭活对照组.主要观察指标:①祖细胞集落数、祖细胞集落维持时间.②祖细胞集落细胞内人巨细胞病毒-AD169DNA. 结果:①集落数和集落维持时间:人巨细胞病毒感染的祖细胞集落数较对照组明显减少(P < 0.01),集落维持时间较对照组明显缩短(P < 0.01).在人巨细胞病毒感染的集落细胞内检测到人巨细胞病毒-DNA的存在;更昔洛韦作用于人巨细胞病毒感染的祖细胞后,与人巨细胞病毒感染的祖细胞比较集落数明显提高,差异有非常显著性意义(P < 0.01) ,集落维持时间明显延长,差异有非常显著性意义(P < 0.05).②集落增殖提高率: 粒-巨噬系祖细胞、红系祖细胞、淋巴系祖细胞、多向造血祖细胞、巨核系祖细胞分别为37.4%,74.2%,40.1%,67.4%,38.9%.③集落细胞内人巨细胞病毒-AD169DNA:荧光定量PCR显示更昔洛韦作用于人巨细胞病毒感染的祖细胞后核酸载量较人巨细胞病毒感染的祖细胞降低,差异有非常显著性意义(P < 0.01).结论:人巨细胞病毒-AD169株在体外能明显抑制粒-巨噬系祖细胞、红系祖细胞、淋巴系祖细胞、多向造血祖细胞及巨核系祖细胞集落细胞的增殖;在体外更昔洛韦有抗人巨细胞病毒的活性,能促进人巨细胞病毒感染的造血祖细胞增殖.     

人巨细胞病毒感染致造血祖细胞增殖抑制与更昔洛韦的影响术

背景：临床研究显示，骨髓移植后人巨细胞病毒感染可阻碍血小板植入、出现表型异常的外周血白细胞，导致骨髓移植失败，这可能是由于人巨细胞病毒感染直接影响了造血祖细胞所致。目的：观察更昔洛韦对人巨细胞病毒感染所致脐血粒一巨噬系祖细胞、红系祖细胞、淋巴系祖细胞、多向造血祖细胞及巨核系祖细胞体外增殖抑制的影响及更昔洛韦对此的保护作用。设计：对比观察性实验。单位：泸州医学院附属医院分子生物学实验室。对象：正常足月顺产新生儿脐血标本20例，每份10mL。由泸州医学院附属医院妇产科提供，产妇对本实验知情同意。实验经医院伦理委员会批准。方法：实验于2004-06／2006-12在泸州医学院附属医院分子生物学实验室完成。采用脐血标本造血祖细胞培养技术，观察、计数100TCID50人巨细胞病毒-AD169感染粒-巨噬系祖细胞、红系祖细胞、淋巴系祖细胞、多向造血祖细胞及巨核系祖细胞后各祖细胞集落数，记录集落维持时间。用PCR和荧光定量PCR技术检测集落细胞内人巨细胞病毒-AD169DNA。将7．5mg/L更昔洛韦作用于人巨细胞病毒感染的造血祖细胞，再分别计集落数、集落维持时间及集落细胞内人巨细胞病毒-AD169DNA。设正常培养的造血祖细胞为空白对照组，设与含灭活性人巨细胞病毒的正常造血祖细胞培养系统为灭活对照组。主要观察指标：①祖细胞集落数、祖细胞集落维持时间。②祖细胞集落细胞内人巨细胞病毒-AD169DNA。结果：①集落数和集落维持时间：人巨细胞病毒感染的祖细胞集落数较对照组明显减少（P〈0．01），集落维持时间较对照组明显缩短（P〈0．01）。在人巨细胞病毒感染的集落细胞内检测到人巨细胞病毒-DNA的存在：更昔洛韦作用于人巨细胞病毒感染的祖细胞后，与人巨细胞病毒感染的祖细胞比?     

人胎盘组织来源造血干/祖细胞及其特性

背景:近年来的研究表明,除已知的人骨髓、外周血和脐带血中存在造血干/祖细胞外,人胎盘组织中也有造血干/祖细胞存在.目前为止,还缺乏对人胎盘组织造血干/祖细胞的增殖分化特性及人胎盘组织淋巴细胞亚群组成和免疫原性等的深入研究.目的:探究人胎盘组织是否含有比脐带血更丰富的造血干/祖细胞,并对其造血祖细胞系增殖分化能力进行检测,同时对人胎盘组织淋巴细胞亚群组成及表型特征进行分析.设计、时间及地点:开放性实验,于2004-01/2006-12在贵州省细胞工程重点实验室完成.材料:经产妇知情同意,无菌采集遵义医学院附属医院产科健康足月分娩新生儿胎盘和脐带血共12份.淋巴细胞亚群检测试剂盒,CD34绝对计数试剂盒(Becton Dickinson公司):CD34磁珠分选试剂盒,FITC标记的CD38单克隆抗体,抗FITC磁珠和MS/LS免疫磁式细胞分选柱(Miltenyi Biotec).方法:脐带血与RPMI-1640培养基(含体积分数为0.1的胎牛血清)按1:1的比例混合,采用Ficoll-Histopaque分离液离心30min,吸取界面层细胞,PBS洗涤一次,获得脐带血单个核细胞.采用机械法加0.25g/L胶原酶消化制备胎盘组织单个细胞悬液,之后同脐带血单个核细胞分离步骤分离胎盘单个核细胞.流式细胞仪检测胎盘单个核细胞中CD34 CD38-, CD34 CD38 造血干/祖细胞(HSPCs)和淋巴细胞亚群的组成比例.免疫磁珠分选法分选人胎盘CD34 CD38-,CD34 D38 造血干/祖细胞,并分别进行粒细胞-单核细胞集落生成单位、红细胞爆裂型集落生成单位、混合集落生成单位系集落形成培养,以评价其造血祖细胞系增殖分化能力.实验全程用脐带血作平行比较分析.主要观察指标:胎盘和脐带血CD34 造血干/祖细胞组成百分率、祖细胞系集落形成能力、淋巴细胞亚群表型及组成特点.结果:[1]胎盘CD34 造血干/祖细胞百分率是脐带血的8.8倍,差异有显著性意义(P<0.01).[2]胎盘中的淋巴细胞总数、T细胞(CD3 CD2 )、B细胞(CD19 )、Th(CD3 CD4 )细胞及Th/Ts比值均明显低于脐带血,而CD8 CD28-T抑制细胞则明显高于脐带血,差异有显著性意义(P<0.01).[3]胎盘CD34 CD38 造血干/祖细胞亚群培养形成的粒细胞-单核细胞集落生成单位、红细胞爆裂型集落生成单位、混合集落生成单位集落数明显高于CD34 CD38-造血干/祖细胞亚群(P<0.01);胎盘与脐带血造血干/祖细胞中相同表型细胞亚群形成的各系集落数比较,差异无显著性意义(P0.05).结论:人胎盘组织富含CD34 造血干/祖细胞,其CD34 CD38 、CD34 CD38-两个造血干/祖细胞亚群均具有增殖分化为粒细胞-单核细胞集落生成单位、红细胞爆裂型集落生成单位、混合集落生成单位的能力,并且人胎盘组织具有淋巴细胞亚群低比例和抑制性T细胞高比例的特点,使其有望成为造血干/祖细胞移植的新来源.     

FLT3配基-FL研究进展

FLT3配基(FL)是一种新近发现的与造血调控密切相关的细胞因子。在体外,单独FL对造血的调控作用有限,但FL可与IL-3、G-CSF、CSF-1、GM-CSF、SCF及IL-6协同促进骨髓及脐血CD34~+细胞形成粒-巨噬细胞集落、粒细胞集落或巨噬细胞集落;可与SCF、IL-7或IL-11协同促进B淋巴系祖细胞的增殖与分化。FL有望用作造血干祖细胞体外扩增的辅助因子,在临床上用作造血干细胞动员剂、免疫佐剂及肿瘤的免疫治疗。     

造血祖细胞动员剂研究进展

寻找安全高效的造血祖细胞动员剂,以增加外周血造血干细胞数量,减少血细胞分离次数.是自体外周血造血祖细胞移植的重要课题之一。近年来,在以叶酸、环磷酰胺、集落刺激因子及白细胞介素等作为造血祖细胞动员剂的研究中,取得了一定进展,本文就此作一综述。     

造血祖细胞动员剂研究进展

寻找安全高效的造血祖细胞动员剂，以增加外周血造血干细胞数量，减少血细胞分离次数，是自体外周血造血祖细胞移植的重要课题之一。近年来，在以叶酸、环磷酰胺、集落刺激因子及白细胞介素等作为造血祖细胞动员剂的研究中，取得了一定进展，本文就此作一综述。     

造血生长因子在骨髓移植中的临床应用

自1966年Bradley等建立小鼠骨髓细胞体外琼脂培养技术以来,先后在来源不同的刺激因子作用下,培养出粒系、红系及巨核系造血祖细胞集落;分子生物学和遗传工程技术的发展,使其中多数因子得到分离、纯化及克隆表达,这些因子有粒细胞集落刺激因子(G—CSF)、巨噬系集落刺激因子(M—CSF)、粒-巨噬细胞集落刺激因子(GM—CSF)及多能祖细胞集落刺激因子,即     

不同的胞外基质对人胚胎干细胞分化为造血祖细胞的影响简

本研究建立人胚胎干细胞分化为造血细胞的新诱导体系,并探讨不同的胞外基质对产生造血祖细胞的影响.选择3种胞外基质——matrigel、纤维黏连蛋白（fibronectin）和Ⅳ型胶原蛋白（collagen Ⅳ）包被培养板,采用直接贴壁培养的诱导方法,分步添加造血生长因子诱导人胚胎干细胞向造血祖细胞分化,用造血集落形成试验检测集落形成细胞数,流式细胞术以及实时定量PCR方法检测造血特异性标志物的表达,比较这3种胞外基质对生成造血祖细胞的差异.结果表明,诱导14 d时Ⅳ型胶原蛋白组形成造血集落形成细胞数目、产生CD34阳性细胞数以及造血特异性基因SCL和CD34的表达量均明显高于matrigel和纤维黏连蛋白两组（P＜0.05）.结论：人胚胎干细胞在胞外基质上直接贴壁诱导能有效地分化为造血祖细胞,且Ⅳ型胶原蛋白更有利于向造血系的分化.     

体外诱导人类诱导性多能干细胞分化为造血干 / 祖细胞的研究简

本研究探讨体外诱导人诱导性多能干细胞（induced pluripotent stem cell,iPSC）分化为造血干/祖细胞的能力.在体外用小鼠骨髓基质细胞OP9与人类iPSC共培养的方法,将iPSC诱导分化为造血干/祖细胞;用流式细胞术检测造血干/祖细胞表面标志物的表达水平;用实时定量PCR检测分化过程中iPSC及造血干/祖细胞的相关基因mRNA表达水平的变化;用免疫磁珠法分离CD34＋造血干/祖细胞并进行半固体集落形成实验检测细胞的集落形成能力.结果表明,iPSC与OP9细胞共培养诱导造血分化的第4天即可观察到iPSC形态变化;流式细胞术检测显示,分化得到的细胞表达已知的造血干/祖细胞相关表面标志物CD34和CD43分子.在体外分化过程中多能性的标志基因Oct4的表达逐渐下降,造血相关转录因子Gata-2的表达逐渐升高,而Runx-1的表达量则呈波浪式变化,CD34表达量逐渐升高.集落培养14 d能够得到红系集落（CFU-E）,粒系集落（CFU-G）,巨核系集落（CFU-M）,粒-巨核系集落（CFU-GM）和混合系集落（CFU-GEMM）.结论：iPSC细胞能够在体外通过与OP9细胞共培养分化为造血干/祖细胞.     

Characterization of a human hematopoietic progenitor cell capable of forming blast cell containing colonies in vitro

A hematopoietic cell (CFU-B1) capable of producing blast cell containing colonies in vitro was detected using a semisolid culture system. The CFU-B1 has the capacity for self-renewal and commitment to a number of hematopoietic lineages. Monoclonal antibody to the human progenitor cell antigen-1 (HPCA-1) and a monoclonal antibody against the major histocompatibility class II antigen (HLA-DR) were used with fluorescence activated cell sorting to phenotype the CFU-B1. The CFU-B1 was found to express My10 but not HLA-DR antigen; experiments using complement-dependent cytotoxicity to eliminate DR positive cells confirmed this finding. Pretreatment of marrow cells with two chemotherapeutic agents, 5-fluorouracil and 4-hydroperoxycyclophosphamide facilitated detection of CFU-B1 derived colonies, while diminishing or totally inhibiting colony formation by other hematopoietic progenitor cells. CFU-B1-derived colony formation was dependent upon the addition of exogenous hematopoietic growth factors. Media conditioned either by the human bladder carcinoma cell line 5637 or lectin stimulated leukocytes, as well as recombinant granulocyte-macrophage colony stimulating factor, interleukin 3 or interleukin 1 alpha promoted blast cell colony formation. By contrast, neither recombinant erythropoietin, recombinant interleukin 4, purified macrophage colony stimulating factor or recombinant granulocyte colony-stimulating factor alone promoted blast cell colony formation.     

Fetal cord blood as an alternative source of hematopoietic progenitor cells: immunophenotype, maternal cell contamination, and ex vivo expansion.

The present study was performed to investigate the character of hematopoietic progenitor cells in fetal cord blood (CB). Thirty blood samples from fetuses at a median of 24 weeks of gestation (range 19-29) and 30 neonatal CB samples were analyzed for their immunophenotype by three-color flow cytometry and examined for the presence of female cells by fluorescence in situ hybridization (FISH). We tested the effects of different cytokine combinations (rhIL-1beta, rhIL-3, rhIL-6, rh erythropoietin [rhEPO], rhGM-CSF plus rhSCF, and rhSCF plus rhflt3-ligand) on the differentiation of 100 CD34+-enriched neonatal CB cells for up to 21 days. Ex vivo expansion of 32 unselected fetal blood samples cells was performed in the presence of rhSCF and rhflt3-ligand. The percentage of CD34+ cells in fetal blood was significantly higher compared with neonatal CB (1.24%+/-0.82% versus 0.33%+/-0.18%, p = 0.0001) and inversely correlated with the age of gestation. The contamination of fetal and neonatal CB with maternal cells was low (1.72%+/-0.89%, range 1.0%-4.0%). By using rhflt3-ligand we were able to expand committed progenitor cells while maintaining cells with stem cell function. The use of expanded fetal immature progenitors might have implications for in utero transplantation and autologous gene therapy.     

The effect of amphotericin B, aztreonam, imipenem and cephalosporins on the bone marrow progenitor cell activity

The effects of certain antibiotics on the colony forming activity of human bone marrow cells in semisolid methylcellulose medium in vitro and on murine BM cells in spleen colony forming units (cfu-s) in vivo were evaluated. Amikacin, gentamicin, piperacillin, co-trimoxazole and pentamidine had little or no effect on human bone marrow progenitor cell function; amphotericin B, aztreonam, ceftazidime and imipenem caused significant suppression of human colony forming unit-erythroid (cfu-e), burst forming unit-erythroid (bfu-e) and colony forming unit-granulocyte macrophage (cfu-gm) at both peak and trough serum concentrations. At molar equivalent concentrations ceftazidime, cefotaxime and cefoperazone caused significant decreases in human cfu-e, bfu-e and cfu-gm in vitro (P less than 0.01) and murine cfu-s in vivo (P less than 0.05); cefoxitin, cefuroxime, ceftizoxime and ceftriaxone did not suppress human bone marrow progenitor cell activity. Gentamicin, piperacillin and ceftriaxone had no effect on murine cfu-s formation. Further studies to evaluate the effect of these antibiotics on human bone marrow in vivo are suggested.     

DLK1 as a potential target against cancer stem/progenitor cells of hepatocellular carcinoma

Delta-like 1 homolog (DLK1; Drosophila) is a hepatic stem/progenitor cell marker in fetal livers that plays a vital role in oncogenesis of hepatocellular carcinoma (HCC). The aim of this study is to investigate whether DLK1 could serve as a potential therapeutic target against cancer stem/progenitor cells of HCC. DLK1(+) and DLK1(-) cells were sorted by fluorescence-activated cell sorting and magnetic-activated cell sorting, respectively, and then were evaluated by flow cytometry. The biological behaviors of these isolated cells and those with DLK1 knockdown were assessed by growth curve, colony formation assay, spheroid colony formation, chemoresistance, and in vivo tumorigenicity. Adenovirus-mediated RNA interference was used to knockdown the endogenous DLK1. We found that DLK1(+) population was less than 10% in almost all 17 HCC cell lines examined. DLK1(+) HCC cells showed stronger ability of chemoresistance, colony formation, spheroid colony formation, and in vivo tumorigenicity compared with DLK1(-) cells. The DLK1(+) HCC cells could generate the progeny without DLK1 expression. Furthermore, DLK1 knockdown could suppress the ability of proliferation, colony formation, spheroid colony formation, and in vivo tumorigenicity of Hep3B and Huh-7 HCC cells. Our data suggested that DLK1(+) HCC cells have characteristics similar to those of cancer stem/progenitor cells. RNA interference against DLK1 can suppress the malignant behaviors of HCC cells, possibly through directly disrupting cancer stem/progenitor cells, which suggested that DLK1 could be a potential therapeutic target against the HCC stem/progenitor cells.     

Inhibition of human macrophage colony formation by interleukin 4

We investigated the effects of human rIL-4 on in vitro hematopoiesis. A profound inhibition of macrophage colony formation by IL-4 was observed, whereas colony growth of other lineages was not affected. Inhibition of macrophage colony growth was not restricted to GM-CSF- induced colony growth but was also present in cultures stimulated with M-CSF. This inhibition was not only observed in cultures of light density bone marrow cells, but also in cultures of monocyte- and T lymphocyte-depleted bone marrow cells. Since a similar inhibition was observed in cultures of CD34+HLA-DR+-enriched bone marrow cells, a direct action of IL-4 on monocyte-committed progenitor cells is suggested.     

Human recombinant granulocyte-macrophage colony stimulating factor and interleukin 3 have overlapping but distinct hematopoietic activities.

The hematopoietic stimulatory activities of human recombinant IL-3 and granulocyte-macrophage colony stimulating factor (GM-CSF) were directly compared using highly enriched human bone marrow progenitor target cells. IL-3 supported a larger number of erythroid and megakaryocytic progenitor cells than did GM-CSF, while GM-CSF supported more myeloid progenitors. IL-3 directly stimulated the division and migration of primitive erythroid burst forming units, while GM-CSF merely sustained their net survival in culture without promoting division and expansion. IL-3 promoted the formation of larger numbers of multipotential granulocyte-erythroid-macrophage-megakaryocyte colony forming unit--derived colonies than did GM-CSF. These data indicate that human IL-3 and GM-CSF have overlapping but distinct hematopoietic activities, and suggest a potential role for the clinical application of combined IL-3/GM-CSF therapy.     

Comparative effects of chlorozotocin and BCNU on hematopoietic precursor cells

Comparative studies to determine the suppressive effects of chlorozotocin (2-[3-(2-chloroethyl)-3-nitrosoureido]-D-glucopyranose) and BCNU (1,3-bis[2-chloroethyl]-1-nitrosourea) on mouse and human hematopoietic precursor cells: granulocyte-macrophage precursor cells (CFU-gm), late erythroid precursor cells (CFU-e), and early erythroid precursor cells (BFU-e) were performed after in vitro incubation of 1 h with drug concentrations based on clinical administration levels. The suppressive effect of chlorozotocin on CFU-gm, BFU-e, and CFU-e hematopoietic precursor cells in the mouse was less than that of BCNU with the most significant difference seen in CFU-e colony formation. For human hematopoietic progenitor cells, however, the suppressive effect of chlorozotocin was far less than that of BCNU. When the effects of 40 micrograms/ml of chlorozotocin and 20 micrograms/ml of BCNU on human marrow were compared, there were statistically significant differences found for CFU-gm colony formation, and BFU-e and CFU-e colony numbers were significantly different for the two drugs at all comparable concentrations tested. Our results confirm the clinical data, and establish that the effects of chlorozotocin on human hematopoietic precursor cells are minimal.     

Osteoprotegerin inhibits proliferation of myeloid progenitor cells

Osteoprotegerin (OPG) and decoy receptor 3 (DcR) are soluble members of the tumor necrosis factor receptor (TNFR) superfamily. Because the proteins are found in the circulation, their effect on hematopoietic progenitor cells was examined. OPG suppressed colony formation by all myeloid progenitor cells stimulated with one or more growth factors. OPG suppressed colony formation by granulocyte, granulocyte-macrophage, erythroid, and multipotential progenitors. Suppression was 64.2-35.0% of control. Although OPG and DcR3 contain approximately 43% identity and approximately 62% similar amino acids in their TNFR-motif-containing regions, DcR3 did not show any effects on hematopoietic progenitor cell proliferation. The data indicate that OPG has a broader spectrum of activity than previously defined and that myelosuppression may need to be monitored for when OPG is used clinically.