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^＋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-β3）、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+调节性T细胞减少对哮喘患者的影响

目的 比较哮喘患者急性发作期和缓解期支气管肺泡灌洗(BALF)中CD4+CD25+调节性T细胞(Treg)数量差异.方法 通过纤维支气管镜从缓解期(25例)及急性发作期(35例)从哮喘患者气道获得BALF,并用流式细胞仪分析技术测CD4+CD25+Treg的细胞数目.结果 哮喘急性发作期BALF中CD4+CD25+Treg细胞数与缓解期比较差异显著,呈下降趋势.结论 Treg数量及与哮喘病情发生发展相关.     

小剂量氨茶碱对支气管哮喘患者外周血CD4+CD25+调节性T细胞凋亡的影响

目的 观察小剂量氨茶碱对分离培养的健康人和支气管哮喘(简称哮喘)患者外周血CD4+CD25+调节性T细胞(T regulatory cells,Treg)凋亡的影响.方法 经密度梯度离心法、尼龙棉柱法、磁珠分离法分离出健康人和哮喘患者外周血CD4+CD25+Treg,分小剂量氨茶碱(1.13 mg/L)、及空白组培养72 h后,用流式细胞仪检测凋亡率变化.结果 ①健康人外周血CD4+CD25+Treg的纯度为77.4%～92.3%,哮喘患者CD4+CD25+Treg的纯度为75.2%～93.8%.②CD4+CD25+Treg占外周血CD4+T细胞的比例在健康组为4.12%～7.98%,在哮喘组为4.51%～8.68%.两者差异无统计学意义.③小剂量氨茶碱均可以诱导健康组及哮喘组外周血CD4+CD25+Treg凋亡率增加(P<0.05).结论 小剂量氨茶碱(1.13 mg/L)可能通过促进CD4+CD25+Treg凋亡来发挥免疫调节作用.     

CD4+CD25+调节性T细胞在支气管哮喘中的研究进展

CD4 CD25 调节性T细胞(CD4 CD25 Treg)是一种表型和功能特异的T细胞亚群,它在抑制自身免疫性疾病的发生,诱导机体免疫耐受机制中发挥着重要作用。研究CD4 CD25 Treg在支气管哮喘中的功能机制,对阐明哮喘的发病机制及探索疾病免疫治疗方面有重要意义。     

CD+4 CD+25调节性T细胞抑制持续性丙型肝炎病毒感染患者CD+4T细胞反应

目的探讨CD+4 CD+25调节性T细胞(CD+4 CD+25Treg细胞)在持续性HCV感染患者CD+4 T细胞下调中的意义.方法流式细胞术检测慢性丙型肝炎患者外周血中CD+4 CD+25Treg细胞的数量以及细胞内因子的合成;与正常人或患者CD+4 CD-25 T细胞共同培养,检测其抑制功能;RT-PCR检测Foxp3的mRNA表达.结果 CD+4 CD+25Treg细胞约占慢性丙型肝炎患者外周血中CD+4 T细胞的(13.5±1.8)%,高于正常对照(5.3±0.8)% (P=0.004);主要合成IL-10,高表达Foxp3;CD+4 CD+25Treg细胞显著抑制CD+4 T细胞的增殖,以及合成IFNγ,并且抑制活性较正常人增高(P=0.034),这种作用不依赖IL-10和转化生长因子β.结论持续性HCV感染患者CD+4 CD+25Treg细胞表达增加,抑制活性增强,特异性抑制Th1反应.     

CD4+CD25+调节性T细胞——免疫治疗新策略

1995年日本学者Sakaguchi等[1]首次证实外周血中CD4+T细胞中5%～10%的CD4+CD25+T细胞具有免疫抑制功能,它们能预防和阻止自身免疫病的发生发展,这群细胞被定义为CD4+CD25+调节性T细胞(regulatory T cells,Treg).近十多年对Treg在自身免疫病发病中的作用及机制进行了深入研究,发现免疫病治疗后Treg治疗免疫病具有广阔应用前景.     

CD4~+CD25~+Treg细胞在急性胰腺炎中作用的研究进展

CD4+CD25+调节性T细胞(Regulatory T cell,CD4+CD25+Treg)是具有负向免疫调节作用的CD4+T淋巴细胞亚群,现认为其在控制自身免疫性疾病的进展、抑制潜在有害的炎性反应及维持免疫稳态等方面起着关键性作用。急性胰腺炎(AP)是临床上常见的急腹症之一,大量研究证实,CD4+CD25+Treg细胞对AP的发病机制具有重要意义,此文就该方面研究进展进行综述。     

CD4+CD25+调节性T细胞在呼吸系统疾病中的作用

CD4+CD25+调节性T细胞(CD4+CD25+regulatory T cell,CD4+CD25+Treg)是一群表型和功能特异的T细胞,可抑制性调节CD4+或CD8+T细胞活化与增殖,在维持机体免疫自稳、调控免疫应答方面起重要作用。1995年Sakaguchi等〔1〕首次报道了CD4+CD25+Treg,证实其抑制免疫反应,降低体外增殖能力,并通过下调外来或自身抗原的免疫应答水     

CD4~+CD25~+调节性T细胞在自身免疫性肝炎发病机制中的作用

自身免疫性肝炎( autoimmune hepatitis,AIH)是一种免疫介导的、慢性肝脏炎症性疾病,以高y球蛋白血症、自身抗体阳性、肝组织学界面炎和免疫抑制治疗有效为特征[1].尽管AIH的发病机制尚未完全阐明,但多项证据表明,遗传易感性、分子模拟学说及调节性T细胞(regulatory T cells,Treg)缺陷参与了自身免疫性肝损伤.免疫系统本身具有区分自己与非己的功能,并可建立及维持自身免疫耐受,以抑制自身抗原的免疫反应,进而预防自身免疫[2].CD4+ CD25+ Treg细胞在维持机体内环境稳定和维持自身免疫耐受方面起重要作用[3].而自身免疫性疾病的发生正是这种免疫耐受被打破,机体不能维持内环境稳定的结果.近年来的研究表明,Treg细胞功能缺陷可能是AIH发病的基础之一[4].本文就CD4+ CD25+ Treg细胞在AIH发病机制中的作用综述如下.     

地塞米松对哮喘小鼠CD4+CD25+调节性T细胞及IL-4、IL-10水平的影响

目的 探讨地塞米松对哮喘小鼠CD4+ CD25+调节性T细胞及IL-4、IL-10水平的影响.方法 30只雄性BALB/c小鼠随机分为三组:正常对照组、哮喘组和地塞米松组.利用卵清白蛋白腹腔注射和雾化吸入制备哮喘模型;通过流式细胞仪检测各组小鼠脾脏单个核细胞CD4+ CD25+调节性T细胞占CD4+T细胞的百分比;使用免疫组织化学方法分析各组IL-4在小鼠肺组织中的表达情况;用酶联免疫吸附试验检测各组小鼠血清IL-10的水平.结果 哮喘组脾脏单个核细胞CD4+CD25+调节性T细胞百分比及IL-10的表达水平较正常对照组和地塞米松组降低(P＜0.05),哮喘组IL-4水平较正常对照组和地塞米松组增高(P＜0.05).结论 地塞米松的抗炎作用可能通过上调CD4+ CD25+调节性T细胞、调节性T细胞亚群失衡的途径来实现.     

Only the CD62L+ subpopulation of CD4+CD25+ regulatory T cells protects from lethal acute GVHD

CD4+CD25+ regulatory T (Treg) cells are potent modulators of alloimmune responses. In murine models of allogeneic bone marrow transplantation, adoptive transfer of donor CD4+CD25+ Treg cells protects recipient mice from lethal acute graft-versus-host disease (aGVHD) induced by donor CD4+CD25- T cells. Here we examined the differential effect of CD62L+ and CD62L- subsets of CD4+CD25+ Treg cells on aGVHD-related mortality. Both subpopulations showed the characteristic features of CD4+CD25+ Treg cells in vitro and did not induce aGVHD in vivo. However, in cotransfer with donor CD4+CD25- T cells, only the CD62L+ subset of CD4+CD25+ Treg cells prevented severe tissue damage to the colon and protected recipients from lethal aGVHD. Early after transplantation, a higher number of donor-type Treg cells accumulated in host mesenteric lymph node (LN) and spleen when CD4+CD25+CD62L+ Treg cells were transferred compared with the CD62L- subset. Subsequently, CD4+CD25+CD62L+ Treg cells showed a significantly higher capacity than their CD62L- counterpart to inhibit the expansion of donor CD4+CD25- T cells. The ability of Treg cells to efficiently enter the priming sites of pathogenic allo-reactive T cells appears to be a prerequisite for their protective function in aGVHD.     

Altered activation of AKT is required for the suppressive function of human CD4+CD25+ T regulatory cells

Suppression by T regulatory cells (Treg cells) is a major mechanism by which the immune system controls responses to self and nonharmful foreign proteins. Although there are many different types of Treg cells, the best characterized are those that constitutively express cell-surface IL-2Ralpha (CD25). We investigated whether altered T-cell-receptor (TCR)-mediated signaling in pure populations of ex vivo human CD4+CD25+ Treg cells might underlie their unique phenotype, including hyporesponsiveness to TCR-mediated activation and lack of cytokine production. CD4+CD25+ Treg cells displayed a consistent defect in phosphorylation of AKT at serine 473 and reduced phosphorylation of the AKT substrates FOXO and S6. Restoration of AKT activity via lentiviral-mediated expression of an inducibly active form of the kinase revealed that reduced activity of this pathway was necessary for the suppressive function of CD4+CD25+ Treg cells. These data represent the first demonstration of a causal association between altered signaling and the function of CD4+CD25+ Treg cells. Moreover, we have created the first system allowing inducible abrogation of suppression through manipulation of the suppressor cells. This system will be a powerful tool to further study the mechanism(s) of suppression by CD4+CD25+ Treg cells.     

CD4+CD25+ T regulatory cells control anti-islet CD8+ T cells through TGF-beta-TGF-beta receptor interactions in type 1 diabetes

Pancreatic lymph node-derived CD4+CD25+ T regulatory (Treg) cells inhibit in situ differentiation of islet-reactive CD8+ T cells into cytotoxic T lymphocytes, thereby preventing diabetes progression. The mechanism by which these Treg cells suppress anti-islet CD8+ T cells is unknown. Here, we show by using a CD8+ T cell-mediated model of type 1 diabetes that transforming growth factor (TGF)-beta-TGF-beta receptor signals are critical for CD4+CD25+ Treg cell regulation of autoreactive islet-specific cytotoxic T lymphocytes. Transgenic expression of tumor necrosis factor alpha from birth to 25 days of age in the islets of B6 mice that constitutively express CD80 on their beta cells results in accumulation of CD4+CD25+TGF-beta+ cells exclusively in the islets and pancreatic lymph nodes, which delays diabetes progression. In contrast, expression of tumor necrosis factor alpha until 28 days of age prevents islet accumulation of CD4+CD25+TGF-beta+ Treg cells, resulting in acceleration to diabetes. Furthermore, adoptive transfer experiments demonstrated that CD4+CD25+ Treg cells could not control na?ve or activated islet-reactive CD8+ T cells bearing a dominant negative TGF-beta receptor type II. Our data demonstrate that, in vivo, TGF-beta signaling in CD8+ T cells is critical for CD4+CD25+ Treg cell suppression of islet-reactive CD8+ T cells in type 1 diabetes.     

自身免疫性甲状腺疾病和CD4~+CD25~+调节性T细胞

自身免疫性甲状腺疾病(AITD)的发生及发展与CD4~+CD25~+调节性T细胞(Treg细胞)的数量和功能密切相关.动物实验证明Treg细胞可抑制AITD的发生.如果清除动物体内的该类细胞,可导致AITD发病或使原有的甲状腺疾病加重,Treg细胞通过抑制效应性T细胞的激活而发挥对AITD的影响作用.无论是胸腺还是外周,不同诱导体系来源的Treg细胞均对AITD有影响作用.     

自身免疫性甲状腺疾病和CD4~+CD25~+调节性T细胞

自身免疫性甲状腺疾病(AITD)的发生及发展与CD4~+CD25~+调节性T细胞(Treg细胞)的数量和功能密切相关.动物实验证明Treg细胞可抑制AITD的发生.如果清除动物体内的该类细胞,可导致AITD发病或使原有的甲状腺疾病加重,Treg细胞通过抑制效应性T细胞的激活而发挥对AITD的影响作用.无论是胸腺还是外周,不同诱导体系来源的Treg细胞均对AITD有影响作用.     

自身免疫性甲状腺疾病和CD4~+CD25~+调节性T细胞

自身免疫性甲状腺疾病(AITD)的发生及发展与CD4~+CD25~+调节性T细胞(Treg细胞)的数量和功能密切相关.动物实验证明Treg细胞可抑制AITD的发生.如果清除动物体内的该类细胞,可导致AITD发病或使原有的甲状腺疾病加重,Treg细胞通过抑制效应性T细胞的激活而发挥对AITD的影响作用.无论是胸腺还是外周,不同诱导体系来源的Treg细胞均对AITD有影响作用.     

Human CD4+CD25+ regulatory T cells: proteome analysis identifies galectin-10 as a novel marker essential for their anergy and suppressive function

CD4(+)CD25(+)Foxp3(+) regulatory T cells (CD25(+) Treg cells) direct the maintenance of immunological self-tolerance by active suppression of autoaggressive T-cell populations. However, the molecules mediating the anergic state and regulatory function of CD25(+) Treg cells are still elusive. Using differential proteomics, we identified galectin-10, a member of the lectin family, as constitutively expressed in human CD25(+) Treg cells, while they are nearly absent in resting and activated CD4(+) T cells. These data were confirmed on the mRNA and protein levels. Single-cell staining and flow cytometry showed a strictly intracellular expression of galectin-10 in CD25(+) Treg cells. Specific inhibition of galectin-10 restored the proliferative capacity of CD25(+) Treg cells and abrogated their suppressive function. Notably, first identified here as expressed in human T lymphocytes, galectin-10 is essential for the functional properties of CD25(+) Treg cells.