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1.
CD4+CD25+调节性T细胞(CD4+CD25+Treg)是一个具有独特免疫调节功能的T细胞亚群,对维持机体免疫动态平衡具有重要作用。它不仅诱导产生自身免疫耐受,防止自身免疫性疾病的发生,而且能够限制免疫防御中T细胞和B细胞的过度活化,避免造成组织损伤。慢性乙型肝炎患者病毒感染的持续原因可能与体内CD4+CD25+Treg细胞数量或者功能异常,从而降低了机体对HBV发挥特异性效应的CD8+T细胞反应有关。  相似文献   

2.
慢性丙型肝炎患者CD4+CD25+调节性T细胞表达增加   总被引:4,自引:0,他引:4  
目的:探讨CD4+CD25+调节性T(Treg)细胞在慢性丙型肝炎患者免疫下调中的意义.方法:流式细胞仪检测慢性丙型肝炎患者外周血中CD4+CD25+Treg细胞的数量;与CD4+CD25-T细胞共同培养,检测其抑制功能;流式细胞仪检测其对CD4+CD25-T细胞合成IFN-γ和IL-4的影响;RT-PCR检测CD4+CD25+Treg细胞中Foxp3的mRNA表达.结果:CD4+CD25+Treg细胞约占慢性丙型肝炎患者外周血中CD4+T细胞的14.1±1.6%,显著高于正常对照5.3±0.8%(P<0.01),显著抑制CD4+T细胞的增殖(P=0.002),以及合成IFN-γ.CD4+CD25+Treg 细胞高表达Foxp3.结论:持续性HCV感染患者CD4+CD25+Treg细胞表达增加,特异性抑制Th1细胞反应.  相似文献   

3.
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.  相似文献   

4.
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.  相似文献   

5.
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.  相似文献   

6.
CD4+ CD25+ 调节性T细胞为新近发现的一群功能成熟的T细胞亚群.其特征性表达叉头盒蛋白3(Foxp3)分子,专职免疫无能和免疫抑制,在维持外周免疫耐受,防止自身免疫性疾病发病中起着极为关键的作用.CD4+ CD25+ 调节性T细胞在自身免疫性甲状腺疾病(AITD)发病中的作用引起了人们的关注.动物实验发现CD4+ CD25+ 调节性T细胞存在与否决定了实验动物是否发生实验性自身免疫性甲状腺炎(EAT)和Graves病.人体研究发现CD4+ CD25+ 调节性T细胞数目和功能异常与人AITD发生密切相关.这些研究结果提示,CD4+ CD25+ 调节性T细胞可能在AITD发病中起重要作用.  相似文献   

7.
目的:探讨慢性淋巴细胞白血病(CLL)患者外周血CD4+CD25+调节性T细胞(Treg细胞)表达及其与预后的相关性。方法:采用流式细胞仪检测50例健康者(对照组)及30例CLL患者(CLL组)治疗前后CD4+CD25+Treg、CD4+CD25+Foxp3+Treg水平。结果:初诊CLL组患者外周血T淋巴细胞数量、CD4+CD25+Treg、CD4+CD25+Foxp3+Treg水平均显著高于对照组,差异有统计学意义(P0.05)。治疗后,CLL组患者外周血T淋巴细胞数量、CD4+CD25+Foxp3+Treg水平显著降低,与初诊时比较差异有统计学意义(P0.05),但仍高于对照组(P0.05)。CLL患者中,Binet临床分期A期患者CD4+CD25+Foxp3+Treg水平显著低于B/C期患者,差异有统计学意义(P0.05)。Spearman相关分析结果显示,Binet临床分期与CD4+CD25+Foxp3+Treg水平呈正相关(r=0.511,P0.05)。结论:CD4+CD25+Foxp3+Treg水平可能是评估CLL患者预后的有效指标。  相似文献   

8.
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  相似文献   

9.
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.  相似文献   

10.
CD4+ CD25+调节性T细胞(CD4+ CD25+Treg细胞)是具有独特免疫调节功能的T细胞亚群,抑制免疫反应,在机体免疫稳态维持、肿瘤免疫及移植耐受等方面发挥重要的作用。近年来,调节性T细胞在肿瘤免疫及治疗的研究中受到越来越广泛的关注。现就调节性T细胞在恶性腹水方面的研究做一简要综述。  相似文献   

11.
12.
CD8+CD25+ cells, which expressed high levels of Foxp3, glucocorticoid-induced tumor necrosis factor receptor (GITR), CCR8, tumor necrosis factor receptor 2 (TNFR2), and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) mRNAs, were identified in the fibrous septa and medullary areas of human thymus. Activated CD8+CD25+ thymocytes did not produce cytokines, but most of them expressed surface CTLA-4 and transforming growth factor beta1 (TGF-beta1). Like CD4+CD25+, CD8+CD25+ thymocytes suppressed the proliferation of autologous CD25-T cells via a contact-dependent mechanism. The suppressive activity of CD8+CD25+ thymocytes was abrogated by a mixture of anti-CTLA-4 and anti-TGF-beta1 antibodies and it was mediated by their ability to inhibit the expression of the interleukin 2 receptor alpha chain on target T cells. These results demonstrate the existence of a subset of human CD8+CD25+ thymocytes sharing phenotype, functional features, and mechanism of action with CD4+CD25+ T regulatory cells.  相似文献   

13.
目的研究非小细胞肺癌患者外周血淋巴细胞中CD3+、CD4+、CD8+、CD4+4的表达水平。方法取65例非小细胞肺癌患者及22例健康正常人外周静脉血,应用流式细胞仪检验非小细胞肺癌患者(实验组)与健康人外周血淋巴细胞中(对照组)CD3+、CD4+、CD8+、CD4+4的表达水平。结果实验组与对照组CD3+、CD3+CD4+、CD3+CD8+、CD4+4在淋巴细胞中的比例存在显著性差异(P<0.05),其中,实验组占总淋巴细胞的比例分别为48.07±10.33%、30.93±6.68%、17.13±3.37%、55.45±4.35%;对照组CD3+、CD3+CD4+、CD3+CD8+、CD4+4占总淋巴细胞的比例分别为58.83±10.88%、34.89±6.45%、23.91±4.42%、62.85±7.56%;但鳞癌与腺癌组CD4+4的表达无显著性差异(P>0.05),其中,鳞癌组CD4+4所占比例为61.32±8.06%,腺癌组为64.43±6.76%。结论非小细胞肺癌患者外周血T细胞亚群及CD4+4的表达水平较正常组均低,其表达水平与组织类型无关。  相似文献   

14.
The expression of CD25 or CD28 on T cells was examined in patients with rheumatic diseases associated with interstitial pneumonitis (IP), in order to investigate the conditions of CD4+CD25+ regulatory T cells and CD8+CD28 suppressor T cells. Fifty-five patients with various rheumatic diseases and 23 normal controls were enrolled. CD4+CD25+ T cells of patients with IP were significantly decreased in comparison with non-IP patients, and the ratio of CD8+CD28 T cells in patients with IP was significantly higher than that in non-IP patients or normal controls. These results for CD8+CD28 T cells were in accord with the decrease in CD8+CD28+ T cells, and may be related to activation-induced CD8+CD28+ T-cell death. Thus, the abnormality of CD4+CD25+ regulatory T cells may be related to the pathogenesis of IP, and the survival and activation of CD8+ T cells.  相似文献   

15.
Abstract

The expression of CD25 or CD28 on T cells was examined in patients with rheumatic diseases associated with interstitial pneumonitis (IP), in order to investigate the conditions of CD4+CD25+ regulatory T cells and CD8+CD28? suppressor T cells. Fifty-five patients with various rheumatic diseases and 23 normal controls were enrolled. CD4+CD25+ T cells of patients with IP were significantly decreased in comparison with non-IP patients, and the ratio of CD8+CD28? T cells in patients with IP was significantly higher than that in non-IP patients or normal controls. These results for CD8+CD28? T cells were in accord with the decrease in CD8+CD28+ T cells, and may be related to activation-induced CD8+CD28+ T-cell death. Thus, the abnormality of CD4+CD25+ regulatory T cells may be related to the pathogenesis of IP, and the survival and activation of CD8+ T cells.  相似文献   

16.
Preeclampsia is a devastating pregnancy-associated disorder affecting 5% to 8% of pregnant women worldwide. It emerges as an autoimmune-driven disease, and, among others, the autoantibodies against angiotensin type 1 receptor II have been proposed to account for preeclampsia symptoms. Despite much attention focused on describing autoantibodies associated with preeclampsia, there is no clue concerning the cell population producing them. CD19(+)CD5(+) B-1a B cells constitute the main source of natural and polyreactive antibodies, which can be directed against own structures. Here, we aimed to identify the B-cell subpopulation responsible for autoantibody production during preeclampsia and to study their regulation, as well as their possible use as markers for the disease. The frequency of CD19(+)CD5(+) cells in peripheral blood of preeclamptic patients is dramatically increased compared with normal pregnant women as analyzed by flow cytometry. This seems to be driven by the high human chorionic gonadotropin levels present in the serum and placenta supernatant of preeclamptic patients versus normal pregnant women. Not only ≈95% of CD19(+)CD5(+) cells express the human chorionic gonadotropin receptor, but these cells also expand on human chorionic gonadotropin stimulation in a lymphocyte culture. Most importantly, isolated CD19(+)CD5(+) cells produce autoantibodies against angiotensin type 1 receptor II, and CD19(+)CD5(+) cells were further detected in the placenta of preeclamptic but not of normal pregnancies where barely B cells are present. Our results identify a B-cell population able to produce pregnancy-pathological autoantibodies as possible markers for preeclampsia, which opens vast diagnostic and therapeutic applications.  相似文献   

17.
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   

18.
We report here a patient with acute monoblastic leukemia whose leukemia cells had CD4 (T4) and CD56 (NKH-1) antigens, in addition to CD36 (OKM5) antigen. The leukemia cells did not have NK or ADCC activities. They showed no rearrangements of immunoglobulin heavy (IgH) chain and T cell receptor (TCR)-beta chain genes, indicating that the leukemia cells were nonlymphoid. The presence of this case suggests that leukemia cells could be originated from monocytes with NK-associated antigen without IgH or TCR rearrangements.  相似文献   

19.
First evidence of cases of haemophilia dates from ancient Egypt, but it was when Queen Victoria from England in the 19th century transmitted this illness to her descendants, when it became known as the “royal disease”. Last decades of the 20th century account for major discoveries that improved the life expectancy and quality of life of these patients. The history and evolution of haemophilia healthcare counts ups and downs. The introduction of prophylactic schemes during the 1970s have proved to be more effective that the classic on-demand replacement of clotting factors, nevertheless many patients managed with frequent plasma transfusions or derived products became infected with the Human Immunodeficiency Virus (HIV) and Hepatitis C virus during the 1980s and 1990s. Recombinant factor VIII inception has decreased the risk of blood borne infections and restored back longer life expectancies. Main concerns for haemophilia healthcare are shifting from the pure clinical aspects to the economic considerations of long-term replacement therapy. Nowadays researchers’ attention has been placed on the future costs and cost-effectiveness of costly long-term treatment. Equity considerations are relevant as well, and alternative options for less affluent countries are under the scope of further research. The aim of this review was to assess the evidence of different treatment options for haemophilia type A over the past four decades, focusing on the most important technological advances that have influenced the natural course of this “royal disease”.  相似文献   

20.
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。  相似文献   

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