骨髓间充质干细胞对肾病综合征大鼠CD4+CD25+调节性T细胞的影响

背景：CD4⁺CD25⁺调节性T细胞功能降低、数量下降已被公认为是肾病综合征患儿免疫失调的重要表现。骨髓间充质干细胞具有免疫调节功能,可上调CD4⁺CD25⁺调节性T细胞,抑制淋巴细胞增殖,并已在许多免疫性疾病方面成功应用。 目的：观察骨髓间充质干细胞移植对原发性肾病综合征大鼠外周血CD4⁺CD25⁺调节性T细胞的影响。 方法：自SD大鼠分离骨髓间充质干细胞,经体外传代培养及鉴定后制备细胞悬液。30只SD大鼠随机均分为3组,生理盐水组和干细胞移植组尾静脉注射阿霉素建立阿霉素肾病大鼠模型,干细胞移植组注射阿霉素当日尾静脉射干细胞1×10⁷;正常组不做处理。 结果与结论：①与正常组比较,生理盐水组大鼠均出现肾病综合征表现,以腹水、大量蛋白尿、低蛋白血症、高胆固醇血症为特征;干细胞移植组较生理盐水移植组则有明显改善(P < 0.05)。②造模第28天,干细胞移植组和生理盐水组大鼠造模后外周血CD4⁺CD25⁺Treg/ CD4⁺ Treg均明显高于正常组(P < 0.05);干细胞移植组与生理盐水组比较差异无显著性意义(P > 0.05)。③造模第28天,干细胞移植组大鼠外周血单个核细胞FoxP3mRNA的表达显著高于生理盐水组和正常组(P < 0.05)。提示骨髓间充质干细胞移植对阿霉素肾病综合征模型有一定的治疗作用,其机制可能与上调FoxP3在组织局部的表达而诱导CD4⁺CD25⁺Treg产生有关。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：     

CD28-B7共刺激通路对外周血单个核细胞移植治疗重症肌无力的作用

背景：有研究表明,CD28-B7共刺激通路与重症肌无力的发生密切相关,但在干细胞移植治疗重症肌无力过程中的作用机制至今少有报道。 目的：观察CD28-B7共刺激通路在重症肌无力大鼠模型中的表达情况。 方法：40只雌性Lewis大鼠等分为正常组、模型组、佐剂组和移植组。后3组大鼠腹腔注射重症肌无力患者血清制备重症肌无力模型。移植组大鼠连续5 d皮下注射粒细胞集落刺激因子10 μg/(kg•d)动员骨髓中造血干细胞进入外周血,颈动脉采血10 mL,分离获得单个核细胞,加入适量生理盐水调节核细胞浓度至2×10⁹ L^-1;环磷酰胺50 mg/kg于移植前第4,3,2天从尾静脉注入,1次/d,移植当天用胰岛素注射针吸取单个核细胞自尾静脉注入,移植成功。佐剂组给予等量生理盐水和环磷酰胺。 结果与结论：移植组大鼠血清抗乙酰胆碱受体滴度、CD28、细胞毒性T淋巴细胞相关抗原4、B7.1及B7.2的表达均显著低于模型组(P < 0.01);模型组和移植组大鼠血清抗乙酰胆碱受体滴度滴度与细胞毒性T淋巴细胞相关抗原4呈正相关(r=0.236,P=0.001和r=0.215,P=0.013);移植组大鼠Lennon评分显著低于模型组(P < 0.01)。提示干细胞移植可以通过抑制CD28-B7共刺激信号通路以调节机体的免疫系统。     

自体干细胞移植治疗糖尿病足的干细胞动员和采集

背景：在自体干细胞移植治疗下肢缺血性疾病的干细胞动员期间,国内外大多数研究组均常规应用5~10 μg/(kg•d)的粒细胞集落刺激因子动员,5 d后采集干细胞进行移植,这是否为最佳的动员时间和采集时机未见相关报道。 目的：分析探讨自体干细胞移植最佳动员方案及采集时机,提高该方法的安全性。 方法：对备行干细胞移植的18例糖尿病足患者分别采用粒细胞集落刺激因子5,10 μg/(kg•d)进行造血干细胞动员,分析粒细胞集落刺激因子动员天数、剂量与外周血白细胞、单个核细胞、CD34⁺细胞数的关系,并检测干细胞动员前后、采集前后患者凝血指标、血小板计数的变化,观察患者动员及采集过程的不良反应。 结果与结论：随着动员天数的增加,白细胞和单个核细胞、CD34⁺细胞数也随之增加,干细胞获得的效率与粒细胞集落刺激因子的剂量、动员时间有关,外周血中CD34⁺总数与单个核细胞总数呈正相关。患者的凝血指标在动员和采集前后无显著变化。血小板计数在动员前后无变化,但在采集后有显著下降;18例患者中仅有1例在粒细胞集落刺激因子动员中发生轻度骨头酸痛,1例出现发热,其他患者均无不良反应发生。提示,糖尿病足患者干细胞采集的最佳时机不能单凭动员天数和外周血白细胞数决定,而是由外周血单个核细胞数和CD34⁺的数量来决定。且干细胞动员和采集对患者的不良反应小,安全性高。     

老年初诊急性髓细胞白血病患者CD4+CD25+调节性T细胞的表达

背景：研究证实,很多恶性肿瘤患者体内CD4⁺CD25⁺调节性T细胞存在高表达,近期也有研究发现,急性髓细胞白血病患者外周血CD4⁺CD25⁺调节性T细胞同样表现出高比例表达。 目的：分析老年初诊急性髓细胞白血病患者CD4⁺CD25⁺调节性T细胞的表达特点。 方法：纳入初诊急性髓细胞白血病患者92例,将年龄在60岁以下者设为中青年组(n=22),年龄在60岁以上者设为老年观察组(n=70)。在老年观察组中,32例经规范化疗后完全缓解,设为完全缓解组;将余下38例设为老年组,依据FAB分型标准,分为M2 6例、M3 19例、M4 7例、M5 6例。另选择同期体检健康人群42名作为正常对照组。抽取受试者外周静脉血,检测CD4⁺CD25⁺调节性T细胞表达情况。 结果与结论：老年组、完全缓解组CD4⁺CD25^highFOXP3⁺调节性T细胞比例高于正常对照组(P < 0.01),并且老年组CD4⁺CD25^high FOXP3⁺调节性T细胞比例高于完全缓解组(P < 0.01)。老年组、完全缓解组CD4⁺FOXP3⁺T细胞比例高于正常对照组(P < 0.01),并且老年组CD4⁺ FOXP3⁺T细胞比例高于完全缓解组(P < 0.01)。老年组CD4⁺CD25^high FOXP3⁺调节性T细胞与CD4⁺ FOXP3⁺T细胞比例高于中青年组(P < 0.01)。老年组不同分型间CD4⁺CD25^high FOXP3⁺调节性T细胞和CD4⁺ FOXP3⁺T细胞比例比较差异均无显著性意义(P > 0.05)。Pearson相关性检验结果显示,老年初诊急性髓细胞白血病患者外周血CD4⁺CD25^high FOXP3⁺调节性T细胞比例和CD4⁺ FOXP3⁺T细胞比例呈正相关(r=0.87,P=0.019)。表明老年初诊急性髓细胞白血病患者CD4⁺CD25⁺调节性T细胞比例高于健康人群和中青年急性髓细胞白血病患者。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：     

单元型相同骨髓移植后患者单核细胞来源的DC表面分子的检测

对单元型相同骨髓移植患者造血重建后的外周血单个核细胞加GM-CSF、IL-4进行DC诱导,7d后加入TNF-α于培养DC中,继续诱导3d。测定DC的表型、混合淋巴细胞反应对T细胞增殖能力的测定,并与健康志愿者外周血来源的DC进行比较。探讨单元型相同造血干细胞移植后患者单个核细胞来源的DC的生物学特性。结果显示,单元型相同造血干细胞移植患者外周血单个核细胞和正常人外周血单个核细胞来源的DC均高表达CD1α、CD83、CD80、CD86和HLA-DR等DC的相关抗原和共刺激分子,患者的未成熟DC经TNF-α诱导后,成为成熟和有功能的DC,单元型相同造血干细胞移植患者单个核细胞来源的DC在体外具有激发同种异体外周血T细胞增殖的能力,与健康人外周血来源DC组相比均无统计学意义(P>0.05)。     

CD34+细胞的心肌细胞分化潜能研究

目的:了解粒细胞集落刺激因子(G-CSF)动员的CD34+细胞的心肌细胞分化潜能。方法:用异丙肾上腺素(ISO)复制急性心肌梗死大鼠动物模型,于3 h后用G-CSF动员骨髓造血干细胞进行心肌梗死动物模型的“自身干细胞移植”,用免疫组化和HE染色方法检测动物模型心梗区的CD34⁺细胞浸润以及心肌细胞再生情况。结果:用ISO后24 h,G-CSF处理组大鼠心梗区可见大量CD34⁺单个核细胞浸润,并有CD34⁺的新生心肌细胞生长,2周后疤痕组织不明显;而对照组心梗坏死区有大量以中性粒细胞为主的炎症细胞浸润,无CD34+细胞浸润及新生心肌细胞生长,2周后出现较大量的疤痕组织。结论:G-CSF动员CD34⁺细胞具有向心肌细胞分化的潜能,用G-CSF 动员造血干细胞的“干细胞自身移植”,可治疗急性心肌梗死。     

结核病患者外周血中CD4~+ CD25~+调节性T细胞水平的检测

探讨CD4~+CD25~+调节性T细胞及其转录因子Foxp3在结核病发病机制中的作用。研究对象为肺结核患者22例(病例组)以及健康对照者23例(对照组)。采用FACS检测外周血CD4~+CD25~+调节性T细胞的百分率,采用real-time PCR检测外周血单个核细胞Foxp3mRNA的表达以及CD4~+CD25~+调节性T细胞与CD4~+T细胞、CD8~+T细胞、IFN-γ和IL-4的相关性。结核病患者外周血CD4~+CD25~+调节性T细胞占CD4~+T细胞的百分率,病例组(3.38±1.23)%高于对照组(1.97±0.62)%,两组比较差异有统计学意义(P0.05)。血清单个核细胞Foxp3 mRNA相对表达水平为134.54±6.76,高于对照组(40.98±2.34,P0.05)。CD4~+CD25~+调节性T细胞与CD4~+T细胞、CD8~+T细胞以及与IFN-γ和IL-4的表达呈负相关。结核病CD4~+CD25~+调节性T细胞数量增加、特异性转录因子Foxp3 mRNA表达上升,由此引发的免疫抑制效应可能是结核病发生发展的重要原因之一。     

CD4+CD25high调节性T细胞在异基因造血干细胞移植后的重建及其与aGVHD的相关性

目的：研究CD4^＋ CD25^high调节性T细胞在异基因造血干细胞移植后的重建情况及其与aGVHD相关性。方法：应用流式细胞技术及实时定量PCR技术检测22例异基因造血干细胞移植物中及移植后不同时期外周血中CD4^＋ CD25^＋T细胞和CD4^＋ CD25^highT细胞占CD4^＋T细胞的比例（CD4^＋ CD25^＋/CD4^＋、CD4^＋ CD25^high/CD4^＋）、CD4^＋ CD25^highT细胞与CD4^＋ CD25^＋T细胞之比（CD4^＋ CD25^high/CD4^＋ CD25^＋）以及FOXP3基因的表达。结果：①aGVHD组移植物中CD4^＋ CD25^high/CD4^＋及CD4^＋ CD25^high/CD4^＋ CD25^＋比例均显著低于无aGVHD组（P〈0.05）。②移植后早期,两组外周血中的CD4^＋ CD25^＋/CD4^＋比例均较移植物中者显著升高,在aGVHD组CD4^＋ CD25^high/CD4^＋及CD4^＋ CD25^high/CD4^＋ CD25^＋比例亦较移植物中者显著升高,而在无aGVHD组两者无显著升高,且低于aGVHD组。③移植后两组的FOXP3的表达均逐渐升高,但至移植后6个月仍低于健康对照组（P〈0.05）。aGVHD组移植后外周血FOXP3的表达低于无aGVHD组（P〈0.05）。结论：①移植后早期外周血CD4^＋ CD25^high调节性T细胞发生活化和增殖,有利于维持免疫稳态和控制aGVHD;②移植物中CD4^＋ CD25^high调节性T细胞的比例及其与活化的CD4^＋效应性T细胞之比可能影响aGVHD的发生;③aGVHD可影响CD4^＋ CD25^high调节性T细胞的数量或FOXP3的表达。     

脐血树突状细胞的诱导和体外抗肿瘤研究

目的：用细胞因子诱导脐血干细胞分化为树突状细胞(dendritic cells，DC)，并观察脐血来源DC疫苗在体外对人肝癌细胞的杀伤活性。方法：用CD34^ 细胞分选试剂盒和Mini MACS从脐血单个核细胞中分离CD34^ 干细胞。重组人粒细胞-巨噬细胞集落刺激因子100μg／ml、重组人肿瘤坏死因子-α50U／ml诱导CD34^ 干细胞向DC分化，     

尾静脉注射骨髓基质细胞和腹腔注射粒细胞集落刺激因子治疗大鼠脑梗死

背景：骨髓间充质干细胞具有成神经分化特性,有很多试验也证实粒细胞集落刺激因子可以用于改善脑梗死后的神经功能。 目的：比较静脉移植骨髓间充质干细胞和腹腔注射粒细胞集落刺激因子动员干细胞来治疗大脑中动脉闭塞模型大鼠疗效。 方法：实验以改良的Zea-longa线栓法阻断大脑中动脉建立SD大鼠脑梗死模型,造模24 h后分别通过尾静脉注射骨髓间充质干细胞或腹腔注射粒细胞集落刺激因子。 结果与结论：两种治疗方法均可改善脑梗死模型大鼠的运动和认知功能,且粒细胞集落刺激因子对脑梗死模型大鼠的运动和认知功能的改善比尾静脉注射骨髓间充质干细胞明显,移植后第7,14天,粒细胞集落刺激因子组梗死面积小于骨髓间充质干细胞组(P < 0.05),粒细胞集落刺激因子组BrdU阳性细胞数多于骨髓间充质干细胞组(P < 0.05)。提示粒细胞集落刺激因子动员骨髓干细胞治疗脑梗死的疗效可能优于骨髓间充质干细胞静脉注射的移植方法。     

Plerixafor Plus Granulocyte Colony-Stimulating Factor Improves the Mobilization of Hematopoietic Stem Cells in Patients with Non-Hodgkin Lymphoma and Low Circulating Peripheral Blood CD34+ Cells

Many institutions have adopted algorithms based on preapheresis circulating CD34+ cell counts to optimize the use of plerixafor. However, a circulating peripheral blood CD34+ cell threshold that predicts mobilization failure has not been defined. The superiority of plerixafor + granulocyte colony-stimulating factor (G-CSF) over placebo + G-CSF for hematopoietic stem cell mobilization and collection was shown for patients with non-Hodgkin lymphoma in a phase III, prospective, randomized, controlled study. The question remains as to which patients may benefit most from the use of plerixafor. In this post hoc retrospective analysis, mobilization outcomes were compared between the 2 treatment arms in patients stratified by peripheral blood CD34+ cell count (<5, 5 to 9, 10 to 14, 15 to 19, or ≥20 cells/μL) obtained before study treatment and apheresis. Compared with placebo plus G-CSF, plerixafor plus G-CSF significantly increased the peripheral blood CD34+ cells/μL over prior day levels in all 5 stratified groups. The probability of subsequent transplantation without a rescue mobilization was far greater in the plerixafor-treated patients for the lowest initial (day 4) peripheral blood CD34+ cells/μL groups (<5, 5 to 9, or 10 to 14). Engraftment and durability were the same for the 2 treatment groups for all strata, but the effect in the lower strata could be altered by the addition of cells from rescue mobilizations. These findings may provide insight into the optimal use of plerixafor in all patients undergoing stem cell mobilization.     

Comparison of retroviral transduction efficiency in CD34+ cells derived from bone marrow versus G-CSF-mobilized or G-CSF plus stem cell factor-mobilized peripheral blood in nonhuman primates

Hematopoietic stem cells (HSCs) are ideal targets for genetic manipulation in the treatment of several congenital and acquired disorders affecting the hematopoietic compartment. Although G-CSF-mobilized peripheral blood CD34(+) cells are the favored source of hematopoietic stem cells in clinical transplantation, this source of stem cells does not provide meaningful engraftment levels of genetically modified cells compared with G-CSF + stem cell factor (SCF)-mobilized cells in nonhuman primates. Furthermore, the use of G-CSF mobilization can have disastrous consequences in patients with sickle cell disease, a long-held target disorder for HSC-based gene therapy approaches. We therefore conducted a study to compare the levels of genetically modified cells attainable after retroviral transduction of CD34(+) cells collected from a bone marrow (BM) harvest with CD34(+) cells collected from a leukapheresis product after mobilization with G-CSF (n = 3) or G-CSF in combination with SCF (n = 3) in the rhesus macaque autologous transplantation model. Transductions were performed using retroviral vector supernatant on fibronectin-coated plates for 96 hours in the presence of stimulatory cytokines. BM was equal to or better than G-CSF-mobilized peripheral blood as a source of HSCs for retroviral transduction. Although the highest marking observed was derived from G-SCF + SCF-mobilized peripheral blood in two animals, marking in the third originated only from the BM fraction. These results demonstrate that steady-state BM is at least equivalent to G-CSF-mobilized peripheral blood as a source of HSCs for retroviral gene transfer and the only currently available source for patients with sickle cell disease.     

Regulatory CD4+CD25hi T cells conserve their function and phenotype after granulocyte colony-stimulating factor treatment in human hematopoietic stem cell transplantation

Acute graft-versus-host disease (aGVHD), mediated by CD4(+) and CD8(+) effector T cells, is a life-threatening complication in hematopoietic stem cell transplantation. CD4(+)CD25(hi) regulatory T cells (T(reg)) have been shown to modulate tolerance to aGVHD in murine models. Based on these observations, we examined their role in the prevention of aGVHD in patients who underwent transplantation with peripheral blood-mobilized hematopoietic stem cells after administration of granulocyte colony-stimulating factor. The effects of the G-CSF on the phenotype, frequency, and function of CD4(+)CD25(hi) T cells were analyzed in grafts and after transplantation to determine whether these cells were regulatory T cells. CD4(+)CD25(hi) T cells could be detected at the same frequency before and after granulocyte colony-stimulating factor administration in the donors' peripheral blood. The isolation of these cells from the grafts or from the recipients' peripheral blood after transplantation revealed that they were suppressive to the same extent as T(reg) isolated from healthy volunteers. Their number and frequency were estimated in the grafts and the results indicated that protection against aGVHD was not dependent on the T(reg) amount transferred to the recipients. Similarly there was no correlation between the number of circulating CD4(+)CD25(hi) T cells in the recipients' peripheral blood during the early period after transplantation and the outcome of aGVHD.     

CD4+CD25+FoxP3+调节T细胞抑制肺结核患者特异细胞免疫

  目的 了解结核患者外周血中CD4+CD25+FoxP3+调节T细胞在抑制结核患者结核特异细胞免疫反应中的作用。 方法 使用细胞分离、流式细胞分析、细胞增殖和细胞因子测定等方法,比较结核患者及健康正常人群外周血中CD4+CD25+FoxP3+调节T细胞的量及功能特征的差异。 结果 结核患者外周血中CD4+CD25+FoxP3+调节T细胞数占CD4+细胞总数的比例显著高于健康正常人群;在BCG及ESAT-6的刺激下,结核患者外周血单个核细胞增殖能力和产生γ-干扰素的能力比健康正常人群明显增强。在BCG刺激下,结核患者外周血CD4-细胞产生γ-干扰素(1289.62±519.01)及白介素-10(1045.40±534.12)的能力比结核患者外周血BPMCs细胞产生γ-干扰素(624.50±261.13)及白介素-10(377.00±249.56)的能力显著增强(均p<0.05);在BCG及ESAT-6的刺激下,结核患者外周血CD4+CD25+调节T细胞显著抑制结核患者外周血CD4+CD25-细胞产生γ-干扰素及白介素-10。 结论 结核患者CD4+CD25+FoxP3+调节T细胞数量增多,抑制结核患者结核特异细胞免疫反应功能增强,可能与结核的发生、发展及转归有密切关系。     

Matched-pair analysis of hematopoietic progenitor cell mobilization using G-CSF vs. cyclophosphamide, etoposide, and G-CSF: enhanced CD34+ cell collections are not necessarily cost-effective.

Using matched-pair analysis, we compared two popular methods of stem cell mobilization in 24 advanced-stage breast cancer patients who underwent two consecutive mobilizing procedures as part of a tandem transplant protocol. For the first cycle, 10 microg/kg/day granulocyte colony-stimulating factor (G-CSF) was given and apheresis commenced on day 4 and continued for < or =5 days (median 3 days). One week after the first cycle of apheresis, 4000 mg/m2 cyclophosphamide, 400 mg/m2 etoposide, and 10 microg/kg G-CSF were administered for < or =16 days (cycle 2). Apheresis was initiated when the white blood cell (WBC) count exceeded 5000 cells/microL and continued for < or =5 days (median 3 days). Mean values of peripheral blood WBC (31,700+/-3200 vs. 30,700+/-3300/microL) were not significantly different between cycles 1 and 2. Mean number of mononuclear cells (MNC) collected per day was slightly greater with G-CSF mobilization than with the combination of chemotherapy and G-CSF (2.5+/-0.21x10(8) vs. 1.8+/-0.19x10(8) cells/kg). Mean daily CD34+ cell yield, however, was nearly six times higher (12.9+/-4.4 vs. 2.2+/-0.5x10(6)/kg; p = 0.01) with chemotherapy plus G-CSF. With G-CSF alone, 13% of aphereses reached the target dose of 5x10(6) CD34+ cells/kg in one collection vs. 57% with chemotherapy plus G-CSF. Transfusions of red blood cells or platelets were necessary in 18 of 24 patients in cycle 2. Three patients were hospitalized with fever for a median of 3 days after cycle 2. No patients received transfusions or required hospitalization during mobilization with G-CSF alone. Resource utilization (cost of drugs, aphereses, cryopreservation, transfusions, hospitalization) was calculated comparing the median number of collections to obtain a target CD34+ cell dose of 5x10(6) cells/kg: four using G-CSF vs. one using the combination in this data set. Resources for G-CSF mobilization cost $7326 vs. $8693 for the combination, even though more apheresis procedures were performed using G-CSF mobilization. The cost of chemotherapy administration, more doses of G-CSF, transfusions, and hospitalizations caused cyclophosphamide, etoposide, and G-CSF to be more expensive than G-CSF alone. A less toxic and less expensive treatment than cyclophosphamide, etoposide, and G-CSF is needed to be more cost-effective than G-CSF alone for peripheral blood progenitor cell mobilization.     

Regulatory CD4+ CD25+ T cells prevent thymic dysfunction in experimental chronic colitis

Chronic colitis in T-cell deficient Tg epsilon26 mice develops due to a dysfunction of the thymus which generates colitogenic T cells after bone marrow (BM) transplantation. Regulatory CD4+ CD25+ T cells have been shown to prevent colitis in this model by normalizing the peripheral T-cell pool. We tested the hypothesis that T-cell normalization takes place in the thymus. Tg epsilon26 mice were transplanted with BM (BM-->Tg epsilon26 mice) and consequently received either CD4+ CD25+ or CD4+ CD25- cells from syngenic wild type mice. Furthermore, untransplanted Tg epsilon26 mice received CD4+ CD25+ or CD4+ CD25- cells or complete mesenteric lymph node cells. Transfer of regulatory. CD4+ CD25+ cells normalized the total number of thymocytes and the percentage and number of double positive CD4+ CD8+ cells in transplanted mice while percentage of single positive CD4+ and CD8+ thymocytes in BM-->Tg epsilon26 mice was reduced upon CD4+ CD25+ transfer. Timing of CD4+ CD25+ cell injection was important as transfer later than 7 days after BM transplantation failed to prevent abnormal thymic T-cell distribution in BM-->Tg epsilon26 mice. Isolated CD4+ CD25+ cell transfer without preceding BM transplantation failed to reconstitute thymic architecture. Differences of thymic cell composition could not be exclusively explained by presence or absence of colitis, respectively, because 19 days after BM transplantation when both groups showed no histological signs of colitis, animals transferred with CD4+ CD25+ T cells had a significantly higher percentage and number of CD4+ CD25+ thymocytes and CD4+ Foxp3+ cells than BM-->Tg epsilon26 mice. In conclusion, early CD4+ CD25+ cotransfer prevents thymic dysfunction which underlies immune-mediated bowel inflammation in BM-->Tg epsilon26 mice.     

ConA刺激对CD4~+CD25~+调节性T细胞趋化特性及其表面趋化因子受体CCR4/CCR6表达的影响

目的体外动态观察ConA激活的调节性T细胞表面趋化因子受体的表达变化及其趋化特性,为利用调节性T细胞诱导免疫耐受提供线索。方法常规分离正常健康人外周血单个核细胞,免疫磁珠阴性分选CD4+T细胞;加FITC-An-tiCD4抗体,APC-AntiCD25抗体,PE-AntiCD127抗体上流式细胞仪分选出CD4hiCD127loCD25hi-int细胞。纯化的调节性T细胞与CD4+CD25-T分别用ConA(10μg/mL)刺激0、24、48h后,用趋化因子CCL1、CCL5、CCL20、CCL22做趋化实验,观察各趋化因子作用下调节性T细胞与CD4+CD25-T细胞的趋化特性。同时,流式细胞仪检测CCR4与CCR6的表达。结果分离得到的调节性T细胞纯度为97.4%,活细胞率为95%,得率:4.1%。CCL1、CCL20、CCL22均可趋化调节性T细胞,且在ConA激活后趋化效率随时间而改变。CCL1与CCL22对调节性T细胞的趋化指数显著高于CD4+CD25-T细胞;CCL20对调节性T细胞和CD4+CD25-T细胞趋化指数都很高;CCL5对调节性T细胞趋化性则显著弱于CD4+CD25-T细胞。ConA刺激后...     

卵巢癌细胞培养上清诱导CD4+CD25-T细胞分化为CD4+CD25+调节性T细胞

目的研究卵巢癌细胞培养上清液是否能诱导外周血CD4^＋CD25^- T细胞转变为CD4^＋CD25^＋调节性T细胞。方法将外周血CD4^＋CD25^- T细胞分离后，对照组用CD3和CD28单抗活化，实验组在对照基础上加用卵巢癌细胞株SKOV3培养上清，72h后分离各组的CD25^＋和CD25^-T细胞，溴化脱氧尿嘧啶掺入标记法测定增殖能力及对静息的自体同源CD4^＋CD25^- T细胞的增殖抑制能力，流式细胞仪测定细胞糖皮质激素诱发型TNF受体（glucocorticoid-induced TNFR,GITR）与CTLA-4分子的表达，RT-PCR检测细胞卿mRNA的表达。结果与对照组相反，实验组的CD4^＋CD25^＋T细胞具有免疫抑制功能，自身增殖能力下降，GITR和CTLA-4分子的表达和CD4^＋CD25^＋调节性T细胞相似，并被诱导表达转录因子Foxp3 mRNA。结论卵巢癌细胞分泌的可溶性物质能诱导外周血CD4^＋CD25^-T细胞转化为CD4^＋CD25^＋调节性T细胞。