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1.
探讨CD4+ CD25+调节性T细胞作为细胞疫苗抑制小鼠同种异体胰岛移植物排斥反应的作用,采用免疫磁珠分离技术分选CD4+ CD25+调节性T细胞联合BALB/cByJ小鼠同种异体胰岛移植.结果 显示,CD4+ CD25+调节性T细胞可明显延长同种异体移植物的存活时间.  相似文献   

2.
乙型肝炎患者外周血CD4+ CD25+调节性T细胞表型与功能分析   总被引:18,自引:0,他引:18  
目的 观察急、慢性乙型肝炎(AHB、CHB)患者外周血CD4+CD25 high调节性T细胞(Treg)的频率、表型和功能特点.方法 采集16例AHB急性发病期(发病后第1周)患者、72例CHB患者和32例健康人的外周血,检测Treg频率,并分析其表面CD45RO、CD45RA、HLA-DR、CD95和细胞内细胞毒T淋巴细胞相关抗原4(CTLA-4)的表达水平.应用实时荧光定量RT-PCR检测CD4+ CD25+、CD4+ CD25-、CD4+和CD4-等细胞亚群和外周血单个核细胞(PBMC)的FoxP3 mRNA表达量.通过MACS免疫磁珠分选Treg,并应用[3H]掺入法检测Treg抑制抗-CD3抗体和HBV抗原刺激的PBMC增殖能力,并观察Treg对HBV抗原或抗-CD3抗体刺激自体PBMC分泌IFNγ的影响.结果 CD4+CD25 high Treg高表达CD45RO、HLA-DR、CD95和细胞内CTLA-4,低表达CD45RA,并且较特异的高表达FoxP3 mRNA.乙型肝炎病人外周血Treg频率与健康对照(3.50±0.72)%比较无统计学差异,但CHB组(3.90±1.44)%显著高于AHB组(3.10±0.87)%,P<0.05.Treg本身对于HBV抗原或抗-CD3抗体刺激没有明显的增殖反应和IFNγ分泌,但可抑制自体PBMC增殖和IFNγ分泌,其中对HBV抗原刺激引起的细胞反应抑制作用较强.结论 HBV感染者外周血Treg较特异地表达FoxP3分子,能抑制HBV抗原特异性细胞免疫反应,这对于深入阐明CHB发病机制具有重要意义.  相似文献   

3.
乙型肝炎患者外周血CD4+ CD25+调节性T细胞表型与功能分析   总被引:8,自引:0,他引:8  
目的 观察急、慢性乙型肝炎(AHB、CHB)患者外周血CD4+CD25 high调节性T细胞(Treg)的频率、表型和功能特点.方法 采集16例AHB急性发病期(发病后第1周)患者、72例CHB患者和32例健康人的外周血,检测Treg频率,并分析其表面CD45RO、CD45RA、HLA-DR、CD95和细胞内细胞毒T淋巴细胞相关抗原4(CTLA-4)的表达水平.应用实时荧光定量RT-PCR检测CD4+ CD25+、CD4+ CD25-、CD4+和CD4-等细胞亚群和外周血单个核细胞(PBMC)的FoxP3 mRNA表达量.通过MACS免疫磁珠分选Treg,并应用[3H]掺入法检测Treg抑制抗-CD3抗体和HBV抗原刺激的PBMC增殖能力,并观察Treg对HBV抗原或抗-CD3抗体刺激自体PBMC分泌IFNγ的影响.结果 CD4+CD25 high Treg高表达CD45RO、HLA-DR、CD95和细胞内CTLA-4,低表达CD45RA,并且较特异的高表达FoxP3 mRNA.乙型肝炎病人外周血Treg频率与健康对照(3.50±0.72)%比较无统计学差异,但CHB组(3.90±1.44)%显著高于AHB组(3.10±0.87)%,P<0.05.Treg本身对于HBV抗原或抗-CD3抗体刺激没有明显的增殖反应和IFNγ分泌,但可抑制自体PBMC增殖和IFNγ分泌,其中对HBV抗原刺激引起的细胞反应抑制作用较强.结论 HBV感染者外周血Treg较特异地表达FoxP3分子,能抑制HBV抗原特异性细胞免疫反应,这对于深入阐明CHB发病机制具有重要意义.  相似文献   

4.
支气管哮喘是一种常见的慢性呼吸道疾病,其免疫发病机制尚不十分清楚。CD4 CD25 调节性T细胞是一种特殊的调节性T细胞,参与自身免疫调节,维持自身免疫耐受。本文就CD4 CD25 调节性T细胞的特性及与支气管哮喘的发病机制、治疗、预后的研究进展做一综述。  相似文献   

5.
OBJECTIVES: The aim of this study was to explore the profile and function of CD4(+)CD25(+) regulatory T cells (Treg cells) in idiopathic thrombocytopenic purpura (ITP) patients. METHODS: Treg cell numbers were analyzed by flow cytometric analysis in peripheral blood mononuclear cells collected from healthy donors or patients with ITP. Quantification of cell proliferation was assayed by an enzyme-linked immunosorbent assay kit, based on the measurement of BrdU incorporation during DNA synthesis. RESULTS: The percentage of Treg cells was significantly decreased in ITP patients in active and non-remission state(5.79 +/- 1.22%) when compared with the patients in remission(11.63 +/- 4.56%) and to healthy subjects(12.68 +/- 3.59%). The suppressive activity of Treg cells in ITP patients was also found to be impaired. CONCLUSION: These results suggest that decreased number and function of Treg cells might be one of mechanisms that cause immune regulation dysfunction in ITP.  相似文献   

6.
Suppression by natural CD4+CD25+ regulatory T cells (Tregs) is one mechanism by which tolerance is maintained. However, the way in which Tregs mediate suppression is not well understood. Here, we show that secreted phospholipase A2 (sPLA2)-IID is selectively produced by Tregs. sPLA2-IID is a potent mediator of Treg function, because it strongly suppressed proliferation of CD4+ and CD8+ T cells in vitro and in vivo in a manner independent of its catalytic activity. Furthermore, sPLA2-IID promoted the differentiation of Tregs, presumably via attenuating signaling through the PI3K/Akt/mammalian target of rapamycin pathway. Importantly, administration of a sPLA2-IID-Fc fusion protein inhibited disease development in murine models of colitis and multiple sclerosis, suggesting that sPLA2-IID''s immunosuppressive function might be exploited therapeutically.  相似文献   

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8.
Aim: To determine whether donor immature dendritic cells (imDCs) combined with a short postoperative course of rapamycin (Rapa) has the ability to expand the CD4+CD25+Foxp3+ regulatory T (Treg) cells and prolong liver allograft survival. Methods: Orthotopic liver transplantation (OLT) was performed from Lewis rats to Brown Norway recipients. Three days before transplantation, animals were injected intravenously with 2 × 106 donor bone marrow‐derived imDCs. Recipient rats (the combined treated group) also received Rapa for 7 d after liver transplantation. Additional groups received either imDCs alone, Rapa alone, or saline alone. Every six recipients from each group were killed at 14 days, 28 days after OLT. The changes of CD4+CD25+Foxp3+ Treg cells in peripheral blood and spleen, histological changes of liver grafts, and serum cytokine levels were investigated. The other six recipients were left in each group to observe the animal survival. Results: Donor imDCs followed by a short postoperative course of Rapa induced long‐term allograft survival. The percentage of CD4+CD25+Foxp3+ Treg cells in CD4+ T cells in the combination treatment group were significantly higher compared with the acute rejection group. Moreover, within the CD4+CD25+ T cell population the combination treatment recipients maintained a higher incidence of Foxp3+ T cells compared with the other groups. Despite the lower serum levels of interleukin (IL)‐2, IL‐12, and interferon‐γ in the combined treated group, the cytokine levels in the combined treated group at 7 days after OLT was nearly twice that at 3 days after OLT but decreased significantly compared with the other groups at 28 days after OLT. Serum IL‐10 level in the combined treated group was higher than the other groups. Conclusions: A single imDC infusion followed by a short postoperative course of Rapa prolongs liver allograft survival and enhances the expansion of Treg cells. This optimal protocol may be a promising administration protocol for the peritransplant tolerance induction.  相似文献   

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11.
目的 研究溃疡性结肠炎(UC)患者外周血CD 4CD 25调节性T细胞比例的变化,探讨其在UC病理机制中的意义.方法 选择UC患者33例,对照组20例.用流式细胞仪检测外周血CD 4CD 25T细胞阳性率.用RT-PCR检测外周单个核细胞(PBMC)中Foxp3 mRNA的表达.用酶联免疫吸附试验检测血清中IL-10和TGF-β的浓度.结果 UC患者CD 4CD 25T细胞占CD 4T细胞的比例明显低于对照组(P<0.01),并且与疾病的活动指数及血沉水平均呈显著负相关(R值分别为-0.660和-0.572,P值均<0.01).UC患者Foxp3 mRNA的表达也明显低于对照组(P<0.01).两组患者血清IL-10和TGF-β的浓度比较无明显差异(P>0.05).结论 UC患者外周血CD 4CD 25 调节性T细胞明显降低,与疾病活动性相关,提示这类细胞可能在UC的病理机制中发挥作用.Foxp3表达降低可能是导致CD 4CD 25 T细胞发育障碍的重要因素.  相似文献   

12.

Background

The clinical use of ex vivo-expanded T-regulatory cells for the treatment of T-cell-mediated diseases has gained increasing momentum. However, the recent demonstration that FOXP3+ T-regulatory cells may contain interleukin-17–producing cells and that they can convert into effector cells once transferred in vivo raises significant doubts about their safety. We previously showed that rapamycin permits the ex vivo expansion of FOXP3+ T-regulatory cells while impairing the proliferation of non-T-regulatory cells. Here we investigated the Th17-cell content and the in vivo stability of rapamycin-expanded T-regulatory cells as pertinent aspects of cell-based therapy.

Design and Methods

T-regulatory-enriched cells were isolated from healthy volunteers and were expanded ex vivo with rapamycin with a pre-clinical applicable protocol. T-regulatory cells cultured with and without rapamycin were compared for their regulatory activity, content of pro-inflammatory cells and stability.

Results

We found that CD4+CCR6+CD161+ T cells (i.e., precursor/committed Th17 cells) contaminate the T-regulatory cells cultured ex vivo in the absence of rapamycin. In addition, Th17 cells do not expand when rapamycin-treated T-regulatory cells are exposed to a “Th17-favorable” environment. Rapamycin-expanded T-regulatory cells maintain their in vitro regulatory phenotype even after in vivo transfer into immunodeficient NOD-SCID mice despite being exposed to the irradiation-induced pro-inflammatory environment. Importantly, no additional rapamycin treatment, either in vitro or in vivo, is required to keep their phenotype fixed.

Conclusions

These data demonstrate that rapamycin secures ex vivo-expanded human T-regulatory cells and provide additional justification for their clinical use in future cell therapy-based trials.  相似文献   

13.
CD4 CD25 调节性T细胞(Treg细胞)是CD4 T细胞的一个亚群,在维持机体自身免疫耐受,诱导移植耐受等方面发挥重要作用。移植物抗宿主病(GVHD)是异基因造血干细胞移植最严重的并发症之一。在动物骨髓移植模型中证实Treg细胞可以促进移植物植入,减少GVHD的发生率和严重度,但并没有消除移植物抗白血病(GVL)的作用。在人体有关Treg细胞对GVHD的影响因研究者分析Treg细胞采用的表型不同,其结论存在不一致性。本文就新近Treg细胞生物学特性,Treg细胞与GVHD和GVL的关系的研究进展进行综述。  相似文献   

14.
目的 研究支气管哮喘(简称哮喘)大鼠模型支气管肺泡灌洗液(BALF)、血液、脾脏CD4+CD25+T细胞的变化,及地塞米松对CD4+CD25+T细胞的影响.方法 50只SD大鼠随机分为5组,空白对照(A)组,哮喘(B)组,地塞米松1(C)组、地塞米松2(D)组,地塞米松3(E)组.A组第l天给予腹腔注射生理盐水l ml,第15~21天每天给予生理盐水雾化.B、C、D、E组用卵蛋白建立哮喘大鼠模型,第1天,每只大鼠腹腔注射抗原l ml(卵蛋白1 mg+灭活百日咳杆菌9×106个+氢氧化铝干粉100 mg)混悬液,第15~21天给予1%的卵蛋白雾化30 min,C、D、E组于雾化后分别给予腹腔注射地塞米松0.2 mg/kg、1 mg/kg、2 mg/kg.采用流式细胞仪检测的方法 ,观察大鼠体内BALF、外周血、脾脏CD4+CD25+T细胞的变化及使用不同剂量地塞米松后对其的影响.结果 B组BALF、外周血、脾脏CD4+CD25+T细胞表达占CD4+T细胞的百分比分别是(42.21±5.62)%、(12.69±2.70)%、(11.15±1.05)%,A组结果 分别是(18.76±5.85)%、(6.21±1.73)%、(7.85±2.13)%.B组与A组比较,差异均具有统计学意义(P<0.01,P<0.01,P<0.05);C组、D组、E组BALF中CD4+CD25+T细胞占CD4+T细胞的百分比表达分别是(10.49±4.03)%、(13.28±5.12)%、(7.51±5.39)%,显著低于A组和B组,(P<0.05,P<0.01);外周血中,C组(6.03±1.43)%、D组(4.88±0.95)%与A组(6.21±1.73)%比较,差异无统计学意义,E组(3.49±0.62)%与C组、A组比较,差异有统计学意义(P<0.05).脾脏中,C组(7.25±1.82)%、D组(8.63±3.18)%与A组(7.85±2.13)%比较,差异无统计学意义,E组(3.38±1.37)%与C组、D组、A组比较,差异有统计学意义(P<0.05).结论 CD4+CD25+T细胞在哮喘大鼠体内有明显的优势表达,可能是哮喘发病的机制之一.地塞米松可以抑制CD4+CD25+T细胞的表达.BALF内CD4+CD25+T细胞的变化与外周血和脾脏的变化具有一致性,监测外周血或脾脏CD4+CD25+T细胞变化可了解肺部情况.  相似文献   

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16.
Autoimmune response suppression by regulatory T cells (Tregs) helps to maintain peripheral immune tolerance, and defects in this mechanism are thought to play a role in the pathogenesis of various autoimmune diseases. In patients with immune thrombocytopenia, naturally occurring CD4(+)CD25(+) Tregs are both functionally impaired and reduced in number. This?study was undertaken to investigate Tregs' role in preventing immune thrombocytopenia in mice. Treg-deficient mice were prepared by inoculation of Treg-depleted CD4(+)CD25(-) T?cells isolated from BALB/c mice into syngeneic nude mice intravenously. Platelet count, proportion of reticulated platelets, platelet-associated IgG, platelet-associated anti-platelet antibodies, and IgG anti-platelet antibody production in splenocyte cultures were examined by flow cytometry. Of 69 Treg-deficient mice, 25 (36%) spontaneously developed thrombocytopenia that lasted at least 5 weeks. The platelet-associated IgG level and proportion of reticulated platelets were elevated in the thrombocytopenic mice. Platelet eluates and splenocyte culture supernatants prepared from thrombocytopenic mice, but not from nonthrombocytopenic mice, contained IgG antibodies capable of binding to intact platelets. Simultaneous transfer of Tregs completely prevented the onset of thrombocytopenia, but Treg transfer after the onset of thrombocytopenia had no apparent effect. Treatment with IgG anti-cytotoxic T?lymphocyte-associated antigen 4 antibody canceled this Treg-governed suppressive effect.?In summary, these results indicate that Tregs play a critical role in preventing murine autoantibody-mediated thrombocytopenia by engaging cytotoxic T lymphocyte-associated antigen?4.  相似文献   

17.
目的研究支气管哮喘(简称哮喘)大鼠模型支气管肺泡灌洗液(BALF)、血液、脾脏CD4^+CD25^+T细胞的变化,及地塞米松对CD4^+CD25^+T细胞的影响。方法50只SD大鼠随机分为5组,空白对照(A)组,哮喘(B)组,地塞米松1(C)组、地塞米松2(D)组,地塞米松3(E)组。A组第1天给予腹腔注射生理盐水1ml,第15~21天每天给予生理盐水雾化。B、C、D、E组用卵蛋白建立哮喘大鼠模型,第1天,每只大鼠腹腔注射抗原1ml(卵蛋白1mg+灭活百日咳杆菌9×10。个+氢氧化铝干粉100mg)混悬液,第15~21天给予1%的卵蛋白雾化30min,C、D、E组于雾化后分别给予腹腔注射地塞米松0.2mg/kg、1mg/kg、2mg/kg。采用流式细胞仪检测的方法,观察大鼠体内BALF、外周血、脾脏CD4^+CD25^+T细胞的变化及使用不同剂量地塞米松后对其的影响。结果B组BALF、外周血、脾脏CD4^+CD25^+T细胞表达占CD4^+T细胞的百分比分别是(42.21±5.62)%、(12.69±2.70)%、(11.15±1.05)%,A组结果分别是(18.76±5.85)%、(6.21±1.73)%、(7.85±2.13)%。B组与A组比较,差异均具有统计学意义(P〈0.01,P〈0.01,P〈0.05);C组、D组、E组BALF中CD4^+CD25^+T细胞占CD4^+T细胞的百分比表达分别是(10.49±4.03)oA、(13.28±5.12)%、(7.51±5.39)%,显著低于A组和B组,(P〈0.05,P〈0.01);外周血中,C组(6.03±1.43)%、D组(4.88±0.95)%与A组(6.21±1.73)%比较,差异无统计学意义,E组(3.49士0.62)%与C组、A组比较,差异有统计学意义(P〈0.05)。脾脏中,c组(7.25±1.82)%、D组(8.63±3.18)%与A组(7.85±2.13)%比较,差异无统计学意义,E组(3.38±1.37)%与C组、D组、A组比较,差异有统计学意义(P〈0.05)。结论CD4^+CD25^+T细胞在哮喘大鼠体内有明显的优势表达,可能是哮喘发病的机制之一。地塞米松可以抑制CD4^+CD25^+T细胞的表达。BALF内CD4^+CD25^+T细胞的变化与外周血和脾脏的变化具有一致性,监测外周血或脾脏CD4^+CD25^+T细胞变化可了解肺部情况。  相似文献   

18.
Autoimmune disease results from the dysregulation of basic tolerogenic processes designed to control self/non-self-discrimination. Approaches to treat autoimmunity have focused historically on potent immunosuppressives that block the activation and expansion of antigen-specific T cells before they differentiate into pathogenic T cell responses. These therapies are very efficient in reducing clonal expansion and altering early signaling pathways. However, once the pathogenic responses are established (i.e., autoimmunity), the interventions are less effective on activated and differentiated T cell subsets (including memory T cells) or acting in the presence of an inflammatory milieu to abort immune responses at the target tissue and systemically. Moreover, the current immunotherapies require continuous use because they do not redirect the immune system to a state of tolerance. The continuous treatment leads to long-term toxicities and can profoundly suppress protective immune responses targeted at viruses, bacteria, and other pathogens. Over the past decade, there have been tremendous advances in our understanding of the basic processes that control immune tolerance. Among the most exciting has been the identification of a professional regulatory T cell subset that has shown enormous potential in suppressing pathologic immune responses in autoimmune diseases, transplantation, and graft vs. host disease. In this review, we summarize current efforts to induce and maintain tolerance in the autoimmune diabetes setting by using therapeutic vaccination with CD4(+)CD25(+) regulatory T cells. Emphasis will be placed on approaches to exploit regulatory T cells either directly or through the use of anti-CD3 immunotherapy.  相似文献   

19.
Graves病患者CD4+CD25+调节性T细胞的变化   总被引:3,自引:0,他引:3  
采用流式细胞术检测Graves病患者外周血CD4^+CD25^+调节性T细胞的水平,分析其表达差异及与甲状腺功能等相关指标的关系。结果显示,Graves病初发患者CD4^+CD25^+调节性T细胞数量减低可能与Graves病发病有关。  相似文献   

20.
Gross DA  Leboeuf M  Gjata B  Danos O  Davoust J 《Blood》2003,102(13):4326-4328
Like cellular transplantation, gene therapy is often limited by immune rejection of the newly expressed antigen. In a model of gene transfer in muscle, delivery of the influenza hemagglutinin (HA) membrane protein by adeno-associated virus (AAV) is impaired by a strong immune response that leads to a rapid rejection of the transduced fibers. We show here that injection of HA-specific CD4+CD25+ T cells from T-cell receptor (TCR)-transgenic animals, concomitant with gene transfer, down-regulates the anti-HA cytotoxic and B-lymphocyte responses and enables persistent HA expression in muscle. This demonstrates for the first time that adoptive transfer of antigen-specific CD4+CD25+ regulatory T cells can be used to induce sustained transgene engraftment in solid tissues.  相似文献   

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