TNF downmodulates the function of human CD4+CD25hi T-regulatory cells

CD4+CD25+ T-regulatory cells (Tregs) play an essential role in maintaining immunologic homeostasis and preventing autoimmunity. However, little is known about the exogenous factors that regulate their differentiation and function. Here, we report that TNF inhibits the suppressive function of both naturally occurring CD4+CD25+ Tregs and TGFbeta1-induced CD4+CD25+ T-regulatory cells. The mechanism of this inhibition involves signaling through TNFRII that is constitutively expressed selectively on unstimulated Tregs and that is up-regulated by TNF. TNF-mediated inhibition of suppressive function is related to a decrease in FoxP3 mRNA and protein expression by the Tregs. Notably, CD4+CD25hi Tregs isolated from patients with active rheumatoid arthritis (RA) expressed reduced levels of FoxP3 mRNA and protein and poorly suppressed the proliferation and cytokine secretion of CD4+ effector T cells in vitro. Treatment with anti-TNF antibody (infliximab) increased FOXP3 mRNA and protein expression by CD4+CD25hi Tregs and restored their suppressive function. Thus, TNF has a novel action in modulating autoimmunity, by inhibiting CD4+CD25+ Treg activity.     

De novo generation of antigen-specific CD4+CD25+ regulatory T cells from human CD4+CD25- cells

Antigen-specificity is a hallmark of adaptive T cell-mediated immune responses. CD4+CD25+FOXP3+ regulatory T cells (T(R)) also require activation through the T cell receptor for function. Although these cells require antigen-specific activation, they are generally able to suppress bystander T cell responses once activated. This raises the possibility that antigen-specific T(R) may be useful therapeutically by localizing generalized suppressive activity to tissues expressing select target antigens. Here, we demonstrate that T(R) specific for particular peptide-MHC complexes can be generated from human CD4+CD25- T cells in vitro and isolated by using HLA class II tetramers. Influenza hemagglutinin epitopes were used to generate hemagglutinin-specific T(R), which required cognate antigen for activation but which subsequently suppressed noncognate bystander T cell responses as well. These findings have implications for the generation of therapeutic regulatory T cells in disease, and also suggest an important mechanism by which T cells may be regulated at the site of inflammation.     

结肠癌细胞上清液对CD4~＋FOXP3~＋调节性T淋巴细胞形成影响

目的观察结肠癌细胞上清液是否能促进正常CD4＋T淋巴细胞转换成调节性T淋巴细胞,并且探讨TGFβ1在促细胞转换中的重要作用。方法应用流式细胞仪染色CD4＋FOXP3＋,ELISA检测结肠癌上清液中TGFβ1浓度。结果分选的CD4＋CD25-细胞纯度高达96.58%±0.59%,这群细胞中表达CD4＋FOXP3＋较低,为0.34%±0.03%。健康正常人CD4＋FOXP3-细胞分别与人结肠癌细胞colo320HSR及DLD-1上清液共培养后,CD4＋FOXP3＋细胞表达增高（colo320HSR组为4.78%±0.41%,DLD-1组为4.48%±0.29%）;这两组与RPMI 1640培养液阴性对照组CD4＋FOXP3＋细胞2.54%±0.41%相比差异有统计学意义（P〈0.05）。ELISA法检测colo320HSR细胞上清液TGFβ1浓度为（1 228.80±10.65）ng/mL,DLD-1细胞上清液TGFβ1浓度（624.50±12.26）ng/mL,而RPMI 1640无血清培养液中未检测到TGFβ1。在与结肠癌细胞上清液培养同时给与TGFβ抗体后,CD4＋FOXP3＋表达较未加入抗体组明显降低（colo320HSR组2.20%±0.09%,P=0.011;DLD-1组1.67%±0.34%,P=0.033）;而RPMI1640阴性对照组CD4＋FOXP3＋细胞表达下降不显著（1.80%±0.58%,P=0.159）。结论人结肠癌细胞上清液可以促进正常CD4＋T淋巴细胞（CD4＋FOXP3-细胞）转换为调节性T淋巴细胞（CD4＋FOXP3＋）,TGFβ1在肿瘤微环境中调节T淋巴细胞形成可能有一定的作用。识别人调节性T淋巴细胞（CD4＋FOXP3＋）的起源将为肿瘤治疗提供重要信息。     

支气管哮喘大鼠CD4+CD25+T细胞的变化及地塞米松干预作用的研究

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.     

支气管哮喘大鼠CD4^＋CD25^＋T细胞的变化及地塞米松干预作用的研究

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。     

CD4+CD25+调节性T细胞与支气管哮喘

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。     

CD4＋CD25＋Treg细胞与支气管哮喘

CD4＋CD25＋Treg细胞的主要作用表现为免疫无能性和免疫抑制性,是外周免疫耐受形成机制的主要组成部分。其主要作用机制为分泌抑制性细胞因子（IL-10和TGF-β）、表达细胞表面分子（CTLA-4、GITR等）及Foxp3等。支气管哮喘患者外周血CD4＋CD25＋Treg功能及数量存在异常,这可能是支气管哮喘发病机制之一。糖皮质激素可以通过影响CD4＋CD25＋Treg的状态起到抑制支气管哮喘气道炎症的作用。     

CD4+CD25+T细胞与支气管哮喘

本文就CD4^＋CD25^＋T细胞的调节机制，CD4^＋CD25^＋T细胞与变态反应的关系，以及CD4^＋CD25^＋T细胞在支气管哮喘发病机制中的作用作一综述。     

CD4+CD25+Treg细胞与支气管哮喘

CD4+ CD25+ Treg细胞的主要作用表现为免疫无能性和免疫抑制性,是外周免疫耐受形成机制的主要组成部分.其主要作用机制为分泌抑制性细胞因子(IL-10和TGF-β)、表达细胞表面分子(CTLA-4、GITR等)及Foxp3等.支气管哮喘患者外周血CD4+ CD25+ Treg功能及数量存在异常,这可能是支气管哮...     

Circulating CD4+CD25+ T cells in rheumatic mitral stenosis

BACKGROUND AND AIM OF THE STUDY: Autoimmunity plays an essential role in the pathogenesis of rheumatic heart disease. Although the ongoing rheumatic process has been demonstrated with high levels of inflammatory markers, the cellular mechanism(s) of autoimmunity have not yet been investigated. The study aim was to examine levels of circulating CD4+CD25+ T cells in patients with rheumatic mitral stenosis, and to evaluate the relationship between regulatory CD4+CD25+ T-cell count and clinical and echocardiographic measures. METHODS: A total of 42 patients with mitral stenosis was enrolled into the study, and 27 normal age- and gender-matched healthy subjects served as controls. All patients and controls underwent clinical, electrocardiographic, echocardiographic and laboratory evaluation. T-cell levels were determined with flow cytometry using monoclonal fluorescein isothiocyanate-labeled anti-CD4 and phycoerythrin-labeled anti-CD25 antibodies. RESULTS: The circulating CD4+CD25+ T-cell count was significantly lower in patients with mitral stenosis than in controls (231 +/- 120 versus 372 +/- 180 per mm3; p = 0.001). The percentage ratio of CD4+CD25+ T cells to total leukocytes and lymphocytes was significantly lower in patients with mitral stenosis than in controls (2.9 +/- 1.5 versus 5.2 +/- 2.1; p < 0.001, and 11.2 +/- 5.6 versus 14.8 +/- 5.6; p = 0.011, respectively). In addition, a significant negative correlation was identified between the erythrocyte sedimentation rate and circulating CD4+CD25+ T-cell count (Spearman rho = -0.414; p = 0.006). No correlation was found between CD4+CD25+ T-cell count and clinical and echocardiographic parameters in patients with mitral stenosis. CONCLUSION: A decrease in CD4+CD25+ T cell numbers in mitral stenosis patients might suggest a role for cellular autoimmunity in a smoldering rheumatic process.     

Stability of human rapamycin-expanded CD4+CD25+ T regulatory cells

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.     

CD4+CD25+Foxp3+调节性T细胞在慢性乙型肝炎患者中的作用

目的 探讨CD4+CD25+Foxp3+调节性T细胞与乙型肝炎慢性化和病毒清除之间的关系.方法 收集慢性活动性乙型肝炎(CAH)患者19例、HBV携带者(AsC)21例、HBV感染恢复者12例和健康对照者15例.通过流式细胞术分析外周血CD4+CD25+Foxp3+T细胞的表型和频率,磁珠分选(MACS)CD4+CD25+T细胞,实时荧光定量PCR方法 分析Foxp3 mRNA基因在CD4+CD25+T细胞的表达水平.统计学处理采用单因素方差分析或非参数检验.结果CAH或AsC组外周血CD4+CD25+Foxp3+T细胞频率以及CD4+CD25+T细胞中Foxp3 mRNA的表达水平显著高于健康对照组或HBV感染恢复者(F=6.8,F=3.72,均P<0.05).免疫组织化学染色发现,CAH患者肝组织Foxp3'T细胞浸润累积较对照组明显增高,但AsC较CAH减少.HBeAg阳性患者(包括CAH和AsC)CD4'CD25'T细胞频率显著高于HBeAg阴性患者(t=2.3,P<0.05),抗-HBe阴性患者显著高于抗-HBe阳性患者(t=2.4,P<0.05).CD4+CD25+Foxp3+T细胞频率与慢性乙型肝炎患者血清中HBV病毒载量存在正相关(r=0.56,P<0.01).结论 慢性乙型肝炎患者CD4+CD25+Foxp3+调节性T细胞异常与乙型肝炎慢性化和病毒清除有关.     

CD4+CD25highT淋巴细胞在强直性脊柱炎发病中的作用

目的 观察CD4^＋CD25^highT淋巴细胞与强直性脊柱炎（AS）发病的相关性，初步探讨调节性T淋巴细胞参与AS发病的可能机制。方法 采用双色直接荧光素标记法和多参数流式细胞术检测50例AS患者及20名正常对照外周血CD4^＋CD25＋T淋巴细胞和CD4^＋CD2^highT淋巴细胞的比例，同时收集临床资料及检测外周血IgA、IgG、IgM、红细胞沉降率（ESR）、C反应蛋白（CRP）水平并进行相关分析。结果 AS患者外周血CD4^＋CD25＋T淋巴细胞与正常对照组差异无统计学意义（P〉0．05），CD4^＋CD25^highT淋巴细胞低于正常对照组（P〈0．05），CD4^＋CD25＋T淋巴细胞与IgA、IgG、IgM、ESR、CRP、病程、骶髂关节X线分级无相关性（P〉0．05）。CD4^＋CD25^highT淋巴细胞与IgG、IgM、ESR、CRP、病程、骶髂关节X线分级无相关性（P〉0．05）。CD4^＋CD25^highT淋巴细胞与IgA相关（P〈0．05）。结论AS患者外周血CD4^＋CD25^highT淋巴细胞比例降低并与IgA相关，可能参与疾病的发生和发展。     

CD25+CD4+ T cells contribute to the control of memory CD8+ T cells

Previously we demonstrated that IL-15 and IL-2 control the number of memory CD8+ T cells in mice. IL-15 induces, and IL-2 suppresses the division of these cells. Here we show that CD25+CD4+ regulatory T cells play an important role in the IL-2-mediated control of memory phenotype CD8+ T cell number. In animals, the numbers of CD25+CD4+ T cells were inversely correlated with the numbers of memory phenotype CD8+ T cells with age. Treatment with anti-IL-2 caused CD25+CD4+ T cells to disappear and, concurrently, increased the numbers of memory phenotype CD8+ T cells. This increase in the numbers of CD8+ memory phenotype T cells was not manifest in animals lacking CD4+ cells. Importantly, adoptive transfer of CD25+CD4+ T cells significantly reduced division of memory phenotype CD8+ T cells. Thus, we conclude that CD25+CD4+ T cells are involved in the IL-2-mediated inhibition of memory CD8+ T cell division and that IL-2 controls memory phenotype CD8+ T cell numbers at least in part through maintenance of the CD25+CD4+ T cell population.     

Therapeutic vaccination using CD4+CD25+ antigen-specific regulatory T cells

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.     

CD4+CD25+T细胞延长同种异体胰岛移植物存活

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.     

CD4+CD25+ regulatory T cells inhibit immune-mediated transgene rejection

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.