从Th1/Th2、Treg/Th17之间的平衡研究轻、中度慢性乙型肝炎患者CD4~+T淋巴细胞的免疫失衡状态

目的从Th17及其相关细胞因子与Th1、Th2、Treg的相互关系,探讨轻、中度CHB患者CD4~+T淋巴细胞的整体免疫失衡状态。方法选择轻、中度CHB患者,与健康志愿者进行比较,观察其外周血各免疫细胞(Th17、Th1、Th2、Treg、Th1/Th2、Treg/Th17)、相关细胞因子(IL-17、IL-6、TGF-β、IFN-γ、IL-4)、主要效应分子(穿孔素、颗粒酶B)和核转录因子(孤独核受体RORγt、Foxp3等)的变化及其相互关系。结果与健康志愿者相比,CHB患者CD8~+T淋巴细胞比例更高,CD4~+/CD8~+比例显著下降,差异有统计学意义(P0.01);与健康志愿者相比,CHB患者Th1细胞比例更高,Th1/Th2显著升高,差异有统计学意义(P0.01);与健康志愿者相比,CHB患者Th17细胞比例更高,Treg/Th17比例显著下降,差异有统计学意义(P0.01);与健康志愿者相比,CHB患者穿孔素和颗粒酶B的表达更高,差异有统计学意义(P0.01);与健康志愿者相比,CHB患者FOXP3、IL17mRNA和RORγt的表达差异无统计学意义(P0.05);与健康志愿者相比,CHB患者TGF-B1、IL-6、IL-17显著增高,差异有统计学意义(P0.01);IFN-γ和IL-4的表达差异无统计学意义(P0.05)。结论轻、中度CHB患者在免疫细胞及其相关细胞因子、效应分子等各环节,尤其是Treg/Th17比例,均处于严重的免疫失衡状态。     

Regulatory Role of CD4+CD25+Foxp3+ Regulatory T Cells on IL-17-Secreting T Cells in Chronic Hepatitis B Patients

Background

Both interleukin (IL)-17-secreting CD4⁺ T (Th17) and CD4⁺CD25⁺Foxp3⁺ T regulatory (Treg) cells have been shown to be associated with disease progression or liver damage in chronic hepatitis B (CHB) patients. However, the relationship between Treg cells and IL-17-secreting T cells in hepatitis B virus (HBV) infections is unclear.

Methods

The frequencies of Treg cells and IL-17-secreting T cells in hepatitis B e antigen (HBeAg)-positive CHB patients and healthy subjects were measured by flow cytometric analysis. The role of Treg cells on the differentiation of Ag-specific IL-17-secreting T cells was determined by removing the Treg cells from peripheral blood mononuclear cells (PBMCs) in HBeAg-positive CHB patients.

Results

The frequencies of both Th17 (1.71 ± 0.58 vs. 1.08 ± 0.36 %; P < 0.01) and Treg cells (8.92 ± 4.11 vs. 6.45 ± 1.56 %; P < 0.01) were increased in the peripheral blood of HBeAg-positive CHB patients compared with healthy controls, but in not the IL-17-secreting CD8⁺ T (Tc17) cells. The frequency of Treg cells was significantly associated with that of Th17 cells (r = 0.625, P = 0.001) in CHB patients. Spearman analysis showed a positive correlation between the frequency of Treg cells and HBV DNA load (r = 0.508, P = 0.008), as well as between the frequency of Th17 cells and serum alanine aminotransferase level (r = 0.516, P = 0.007). The deletion of Treg cells significantly enhanced both Th17 and Tc17 cell development in PBMCs following recombinant HBV core antigen stimulation.

Conclusions

Our data indicate a clear inverse relationship between Th17 cells and Treg cells and that Treg cells can inhibit Th17 cell development in CHB patients.     

CD4+CD25+ T cells in skin lesions of patients with cutaneous leishmaniasis exhibit phenotypic and functional characteristics of natural regulatory T cells

Endogenous regulatory T (Treg) cells are involved in the control of infections, including Leishmania infection in mice. Leishmania viannia braziliensis is the main etiologic agent of cutaneous leishmaniasis (CL) in Brazil, and it is also responsible for the more severe mucocutaneous form. Here, we investigated the possible involvement of Treg cells in the control of the immune response in human skin lesions caused by L. viannia braziliensis infection. We show that functional Treg cells can be found in skin lesions of patients with CL. These cells express phenotypic markers of Treg cells--such as CD25, cytotoxic T lymphocyte-associated antigen 4, Foxp3, and glucocorticoid-induced tumor necrosis factor receptor--and are able to produce large amounts of interleukin-10 and transforming growth factor- beta . Furthermore, CD4+CD25+ T cells derived from the skin lesions of 4 of 6 patients with CL significantly suppressed in vitro the phytohemagglutinin-induced proliferative T cell responses of allogeneic peripheral-blood mononuclear cells (PBMCs) from healthy control subjects at a ratio of 1 Treg cell to 10 allogeneic PBMCs. These findings suggest that functional Treg cells accumulate at sites of Leishmania infection in humans and possibly contribute to the local control of effector T cell functions.     

Induction of autoimmune thyroiditis by depletion of CD4+CD25+ regulatory T cells in thyroiditis-resistant IL-17, but not interferon-gamma receptor, knockout nonobese diabetic-H2h4 mice

Iodine-induced experimental autoimmune thyroiditis in the nonobese diabetic (NOD)-H2h4 mouse is a prototype of animal models of Hashimoto's thyroiditis in humans. Recent studies have shown the resistance to thyroiditis of NOD-H2h4 mice genetically deficient for either IL-17 or interferon (IFN)-γ, implicating both of T helper type 1 (Th1) and Th17 immune responses in disease pathogenesis. However, we hypothesized that robust induction of a single arm of effector T cells (either Th1 or Th17) might be sufficient for inducing thyroiditis in NOD-H2h4 mice. To address this hypothesis, enhanced immune responses consisting of either Th1 or Th17 were induced by anti-CD25 antibody-mediated depletion of regulatory T cells (Treg) in thyroiditis-resistant IL-17 knockout (KO) or IFN-γ receptor (IFN-γR) KO, respectively, NOD-H2h4 mice. Depletion of Treg in IL-17 KO mice (i.e. Th1 enhancement) elicited antithyroglobulin autoantibodies and thyroiditis. Immunohistochemical analysis of the thyroid glands revealed the similar intrathyroidal lymphocyte infiltration patterns, with CD4+ T and CD19+ B cells being dominant between the wild-type and Treg-depleted IL-17 KO mice. In contrast, Treg-depleted IFN-γR KO mice remained thyroiditis resistant. Intracellular cytokine staining assays showed differentiation of Th1 cells in IL-17 KO mice but not of Th17 cells in IFN-γR KO mice. Our findings demonstrate that a robust Th1 immune response can by itself induce thyroiditis in otherwise thyroiditis-resistant IL-17 KO mice. Thus, unlike Th17 cells in IFN-γR KO mice, Th1 cells enhanced by Treg depletion can be sustained and induce thyroiditis.     

Association of CD4+ T cell subpopulations and psychological stress measures in women living with HIV

Psychological stress is a known immunomodulator. In individuals with HIV, depression, the most common manifestation of increased psychological stress, can affect immune function with lower CD4+ T cell counts correlating with higher levels of depression. It is unknown how other forms of psychological stress can impact immune markers in people living with HIV. We conducted a cross-sectional study to determine how CD4+ T cell subpopulations correlated with different forms of psychological stress. We recruited 50 HIV-positive women as part of the Women’s Interagency HIV Study. We assessed perceived stress, worry, acute anxiety, trait anxiety, and depression through self-report questionnaires and CD4+ T cell subpopulations using flow cytometry. Our sample was 96% African-American with a mean?±?SD age and body mass index of 42?±?8.8 years and 36.6?±?11.5?kg/m², respectively. The mean?±?SD scores on the psychological measures were as follows: Perceived Stress Scale (PSS), 16.5?±?6.4; Penn State Worry Questionnaire (PSWQ), 47.7?±?13.8; State-Trait Anxiety Inventory – State (STAIS), 39.1?±?12.3; State-Trait Anxiety Inventory – Trait (STAIT), 40.2?±?11.4; Center for Epidemiological Studies Depression Scale (CES-D), 15.6?±?11.4. The mean?+?SD values for the immune parameters were as follows: regulatory T cells (Treg), 1.25%?±?0.7; T helper 1 (Th1), 14.9%?±?6.1; T helper 2 (Th2), 3.8%?±?2; Th1/Th2 ratio, 4.6?±?3; and CD4+ T cell count (cells/mm³), 493?±?251. Treg levels positively correlated with PSS, STAIS, and STAIT. CD4+ T cell count negatively correlated with PSS, PSWQ, STAIS, STAIT, and CES-D. These data suggest that immune function may be impacted by various forms of psychological stress in HIV-positive women. Interventions that target stress reduction may be useful in improving immune parameters and quality of life.     

CD4+ T细胞亚群在血吸虫感染中的动态变化及功能研究进展

血吸虫病是一种主要以肝、肠虫卵肉芽肿和随之伴随的纤维化为主要特征的免疫病理性疾病。一般认为,CD4+ T细胞亚群在抗血吸虫感染及免疫调控过程中起着重要作用。其中辅助性T（T helper,Th）细胞1（Th1）、2（Th2）是主要的效应性CD4+ T细胞亚群,而调节性T（Regulatory T,Treg）细胞在血吸虫感染免疫病理机制中总体起免疫下调作用,新近发现的Th17细胞也积极参与抗血吸虫免疫反应。随着血吸虫感染的进展,这4种CD4+ T细胞亚群数量及功能呈现不同变化趋势,但均对血吸虫感染发生、发展及纤维化病理进程起重要的调控作用。此外,这些CD4+ T细胞亚群之间也存在复杂的相互调节（Cross?talk）。本文就血吸虫感染过程中Th1、Th2、Th17 和 Treg细胞亚群及其效应细胞因子的动态变化与功能的研究进展作一综述。     

Restoring homeostasis of CD4~+ T cells in hepatitis-B-virusrelated liver fibrosis

Immune-mediated liver injury is widely seen during hepatitis B virus(HBV) infection. Unsuccessful immune clearance of HBV results in chronic hepatitis and increases the risk of liver cirrhosis and hepatocellular carcinoma. HBV-related liver fibrosis(HBVLF),occurring as a result of HBV-induced chronic hepatitis,is a reversible,intermediate stage of chronic hepatitis B(CHB) and liver cirrhosis. Therefore,defining the pathogenesis of HBVLF is of practical significance for achieving better clinical outcomes. Recently,the homeostasis of CD4+ T cells was considered to be pivotal in the process of HBVLF. To better uncover the underlying mechanisms,in this review,we systematically retrospect the impacts of different CD4+T-cell subsets on CHB and HBVLF. We emphasize CD4+ T-cell homeostasis and the important balance between regulatory T(Treg) and T helper 17(Th17) cells. We discuss some cytokines associated with Treg and Th17 cells such as interleukin(IL)-17,IL-22,IL-21,IL-23,IL-10,IL-35 and IL-33,as well as surface molecules such as programmed cell death protein 1,cytotoxic T lymphocyte-associated antigen 4,T cell immunoglobulin domain and mucin domain-containing molecule 3 and cannabinoid receptor 2 that have potential therapeutic implications for the homeostasis of CD4+ T cells in CHB and HBVLF.     

Faecalibacterium prausnitzii 对人外周血单核细胞IL-10、IL-12分泌以及CD25^＋Foxp3^＋Treg细胞分化的影响

背景：Faecalibacterium prausnitzi（FP）是人体肠道中常见的共生厌氧菌,与炎症性肠病的关系密切。目的：研究FP对人外周血单核细胞（PBMCs）白细胞介素（IL）-10、IL-12分泌以及CD25^＋Foxp3^＋Treg细胞分化的影响。方法：将FP、长双歧杆菌、大肠杆菌、不同浓度的FP上清或不同细菌培养基分别与人PBMCs体外共培养后,采用ELISA法检测细胞培养上清液中IL-10和IL-12浓度;流式细胞术检测CD25^＋Foxp3^＋Treg细胞比例。结果：与培养基相比,FP、长双歧杆菌均可刺激PBMCs分泌大量IL-10和IL-12,IL—10／IL-12比值明显增高,CD25^＋Foxp3^＋Treg细胞分化明显增加,且FP的效果优于长双歧杆菌。FP上清对IL-10／IL-12比值的作用呈浓度依赖性,稀释10倍的FP上清组IL-10／IL-12比值升高最为明显,且CD25^＋Foxp3^＋Treg细胞分化能力亦最为显著。结论：FP及其上清均具有抗炎作用和促进外周血CD25^＋Foxp3^＋Treg细胞分化的能力,提示FP是一种潜在的益生菌。     

结核性胸膜炎患者外周血CD4CD25调节性T细胞水平及Foxp3mRNA表达的分析

目的观察结核性胸膜炎患者外周血单个核细胞（PBMCs）中CD4 CD25调节性T细胞(CD4 CD25 Treg)水平及Foxp3 mRNA表达的变化,探讨CD4 CD25 Treg在结核性胸膜炎发病中的作用。方法采用流式细胞仪检测58例结核性胸膜炎患者和51例健康志愿者（正常对照组）PBMCs中CD4 CD25 Treg的比例;RT-PCR检测PBMCs中Foxp3 mRNA的表达。结果结核性胸膜炎患者PBMCs中CD4 CD25 Treg的比例明显高于正常对照组(P<0.05);Foxp3 mRNA的表达明显高于正常对照组(P<0.05)。 结论结核性胸膜炎患者外周血中具有免疫抑制活性CD4 CD25 Treg的数量增加,功能增强,可能是结核性胸膜炎发生发展的一个因素。     

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+Foxp3+调节性T细胞在不同月龄小鼠中的变化及与肺癌关系

目的 探讨CD4+CD25+Foxp3+调节性T(Treg)细胞在衰老过程中的变化及与肺癌的关系.方法 建立Lewis肺癌模型,36只C57BL/6小鼠分成6组,青年健康组、中年健康组、老年健康组以及青年肿瘤组、中年肿瘤组、老年肿瘤组.通过流式细胞分析法测定6组小鼠脾脏细胞中CD4+CD25+Foxp3+Treg占CD4+T细胞的百分比来反映CD4+CD25+Foxp3+Treg细胞含量,通过实时荧光定量PCR法测定Foxp3mRNA的含量.结果 与健康组相比,肺肿瘤鼠脾脏中CD4+CD25+Foxp3+/CD4+T细胞和Foxp3 mRNA的含量明显增高(均P＜0.05);在健康组内,各年龄段CD4+CD25+Foxp3+/CD4+T细胞(F=47.70,P=0.000)和Foxp3mRNA(F=6.56,P=0.009)差异有统计学意义,老年鼠脾脏细胞中含有高数量的CD4+CD25+Foxp3+Treg细胞和Foxp3mRNA,最高组是老年肺肿瘤鼠.结论 CD4+CD25+Foxp3+Treg细胞和其功能基因Foxp3含量的改变与增龄和肺肿瘤的发生和发展存在密切的关系.

Abstract：

Objective To explore the change of CD4+CD25+Foxp3+ regulatory T (Treg) cells during aging and the relation with lung tumor. Methods The Lewis lung cancer model was set up in C57BL/6 female mice, and the 36 mice were divided into young health group, middle-aged health group, elderly health group, young tumor group, middle-aged tumor group and elderly tumor group. The percentages of CD4+CD25+Foxp3+ Treg in CD4+ T cells in mice spleen cells were measured by flow cytometry, for reflecting the quantity of CD4+CD25+Foxp3+ Treg cells. And the level of Foxp3 mRNA in splenocyte was tested by real-time PCR method. Results The level of CD4+CD25+Foxp3+/CD4+ T cells and the quantity of Foxp3 mRNA were higher in tumor groups than in healthy groups(both P＜0.05 ). Besides, in the healthy groups, there were statistical differences in the level of CD4+CD25+Foxp3+/CD4+ T cells (F=47.70, P=0.000) and the quantity of Foxp3 mRNA among the different months groups. Accumulation of the CD4+CD25+Foxp3+ Treg cells was accompanied with aging, the elderly mice contained a significantly larger population of CD4+CD25+Foxp3+ Treg cells in their spleen when compared with the younger counterparts, and the highest was the elderly tumor group. So it was with the functional gene Foxp3 mRNA (F=6.56, P=0.009). Conclusions The results suggest a close relationship of the change of CD4+CD25+Foxp3+Treg cells with aging and the genesis and development of lung tumor.     

Foxp3 expression on normal and leukemic CD4+CD25+ T cells implicated in human T-cell leukemia virus type-1 is inconsistent with Treg cells

Foxp3 is a master gene of Treg cells, a novel subset of CD4⁺ T cells primarily expressing CD25. We describe here different features in Foxp3 expression profile between normal and leukemic CD4⁺CD25⁺ T cells, using peripheral blood samples from healthy controls (HCs), human T-cell leukemia virus type-1 (HTLV-1)-infected asymptomatic carriers (ACs), patients with adult T-cell leukemia (ATL), and various hematopoietic cell lines. The majority of CD4⁺CD25⁺ T cells in HCs were positive for Foxp3, but not all CD4⁺CD25⁺ T cells in ACs were positive, indicating that Foxp3 expression is not always linked to CD25 expression in normal T cells. Leukemic (ATL) T cells constitutively expressing CD25 were characteristic of heterogeneous Foxp3 expression, such as intra- and inter-case heterogeneity in intensity, inconsistency with CD25 expression, and a discrepancy in the mRNA and its protein expression. Surprisingly, a discernible amount of Foxp3 mRNA was detectable even in most cell lines without CD25 expression, a small fraction of which was positive for the Foxp3 proteins. The subcellular localization of Foxp3 in HTLV-1-infected cell lines was mainly cytoplasmic, different from that of primary ATL cells. These findings indicate that Foxp3 has two facets: essential Treg identity and molecular mimicry secondary to tumorigenesis. Conclusively, Foxp3 in normal T cells, but not mRNA, is basically potent at discriminating a subset of Treg cells from CD25⁺ T-cell populations, whereas the modulation of Foxp3 expression in leukemic T cells could be implicated in oncogenesis and has a potentially useful clinical role.     

Depletion of Foxp3+ Regulatory T Cells Promotes Profibrogenic Milieu of Cholestasis-Induced Liver Injury

Background

Accumulating evidence suggests that Foxp3+ regulatory T (Treg) cells act as inhibitory mediators of inflammation; however, the in vivo mechanism underlying this protection remains elusive in liver diseases.

Aims

To clarify the in vivo role of Foxp3+ Treg cells in liver fibrosis, we used the DEREG mouse, which expresses the diphtheria toxin receptor under control of the Foxp3 promoter, allowing for specific deletion of Foxp3+ Treg cells.

Methods

Bile duct ligation-induced liver injury and fibrosis were assessed by histopathology, fibrogenic gene expression, and measurement of cytokine and chemokine levels.

Results

Depletion of Foxp3+ Treg cells enhanced Th17 cell response as demonstrated by the increase of IL-17+ cells and related gene expressions including Il17f, Il17ra, and Rorgt in the fibrotic livers of DEREG mice. Of note, infiltration of CD8+ T cells and Cd8 gene expression was significantly increased in the livers of DEREG mice. Consistent with increased IL-17+ and CD8+ T cell responses, DEREG mice generated higher levels of inflammatory cytokines (TNF-α, IL-6, and IL-12p70) and chemokines (MCP-1, MIP-1α, and RANTES). These results were concordant with severity of liver fibrosis and hepatic enzyme levels (ALT and ALP).

Conclusions

The present findings demonstrate that Foxp3+ Treg cells inhibit the profibrogenic inflammatory milieu through suppression of pro-fibrogenic CD8+ and IL-17+ T cells.

     

Plasticity of human Th17 cells and iTregs is orchestrated by different subsets of myeloid cells

CD4+ T helper cell differentiation is essential for mounting robust immune responses without compromising unresponsiveness toward self-tissue. Here, we show that different subsets of myeloid cells isolated from human peripheral blood modulate TGF-β-dependent CD4+ T-cell developmental programs ex vivo. Human CD14+HLA-DR(-/low) myeloid-derived suppressor cells (MDSCs) induce Foxp3+ regulatory T cells, whereas CD14+HLA-DR+ monocytes promote generation of IL-17-secreting RORc+ Th17 cells when cocultured with naive CD4+ T cells. More importantly, not only do these 2 subsets modulate the de novo induction of Tregs and Th17 cells from CD4+ T cells, but MDSCs also catalyze the transdifferentiation of Foxp3+ regulatory T cells from monocyte-induced Th17 cells. The mechanism of such Th17 plasticity is dependent on MDSC-derived TGF-β and retinoic acid. Our results identify a previously unknown feature of the different subsets of CD14+ myeloid cells namely their pivotal role in immune response regulation and plasticity of CD4+ T helper cells. We propose that different subsets of myeloid cells in humans can orchestrate the differentiation of naive CD4+ T cells into effector/regulatory T-cell subsets. The balance between these 2 subsets can impact the outcome of immune reaction from inflammation to tolerance.     

外周血Th17细胞及IL-17^＋FoxP3^＋T细胞在非小细胞肺癌患者的表达变化

目的：探讨辅助性T17（Th17）细胞及白细胞介素17（IL-17）＋叉头蛋白3（FoxP3）＋T细胞在非小细胞肺癌患者外周血中的表达及意义。方法：57例非小细胞肺癌患者作为研究对象．25名正常人作为对照。采用流式细胞术检测外周血Th17细胞、调节性T细胞（Treg细胞）的百分率以及IL-17＋FoxP3＋T细胞占Treg细胞的百分率。结果：Ⅳ期非小细胞肺癌患者外周血单核细胞（PBMC）中Th17细胞百分率高于Ⅰ-Ⅲ期患者及正常对照（均P〈0．01）。非小细胞肺癌患者PBMC中的Treg细胞百分率高于正常对照,并且IL-17＋FoxP3＋T细胞占Treg细胞的百分率高于正常对照（P〈0．05）。结论：Ⅳ期非小细胞肺癌患者中Th17细胞以及II-17＋FoxP3＋T细胞数量增加,Th17以及IL．17＋FoxP3＋T细胞可能参与了非小细胞肺癌的肿瘤远处转移过程．从而影响肿瘤进程。     

Generation of regulatory dendritic cells and CD4+Foxp3+ T cells by probiotics administration suppresses immune disorders

The beneficial effects of probiotics have been described in many diseases, but the mechanism by which they modulate the immune system is poorly understood. In this study, we identified a mixture of probiotics that up-regulates CD4⁺Foxp3⁺ regulatory T cells (Tregs). Administration of the probiotics mixture induced both T-cell and B-cell hyporesponsiveness and down-regulated T helper (Th) 1, Th2, and Th17 cytokines without apoptosis induction. It also induced generation of CD4⁺Foxp3⁺ Tregs from the CD4⁺CD25⁻ population and increased the suppressor activity of naturally occurring CD4⁺CD25⁺ Tregs. Conversion of T cells into Foxp3⁺ Tregs is directly mediated by regulatory dendritic cells (rDCs) that express high levels of IL-10, TGF-β, COX-2, and indoleamine 2,3-dioxygenase. Administration of probiotics had therapeutical effects in experimental inflammatory bowel disease, atopic dermatitis, and rheumatoid arthritis. The therapeutical effect of the probiotics is associated with enrichment of CD4⁺Foxp3⁺ Tregs in the inflamed regions. Collectively, the administration of probiotics that enhance the generation of rDCs and Tregs represents an applicable treatment of inflammatory immune disorders.