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CD4+ T cells differentiate into subsets that promote immunity or minimize damage to the host. T helper 17 cells (Th17) are effector cells that function in inflammatory responses. T regulatory cells (Tregs) maintain tolerance and prevent autoimmunity by secreting immunosuppressive cytokines and expressing check point receptors. While the functions of Th17 and Treg cells are different, both cell fate trajectories require T cell receptor (TCR) and TGF-β receptor (TGF-βR) signals, and Th17 polarization requires an additional IL-6 receptor (IL-6R) signal. Utilizing high-resolution phosphoproteomics, we identified that both synergistic and additive interactions between TCR, TGF-βR, and IL-6R shape kinase signaling networks to differentially regulate key pathways during the early phase of Treg versus Th17 induction. Quantitative biochemical analysis revealed that CD4+ T cells integrate receptor signals via SMAD3, which is a mediator of TGF-βR signaling. Treg induction potentiates the formation of the canonical SMAD3/4 trimer to activate a negative feedback loop through kinases PKA and CSK to suppress TCR signaling, phosphatidylinositol metabolism, and mTOR signaling. IL-6R signaling activates STAT3 to bind SMAD3 and block formation of the SMAD3/4 trimer during the early phase of Th17 induction, which leads to elevated TCR and PI3K signaling. These data provide a biochemical mechanism by which CD4+ T cells integrate TCR, TGF-β, and IL-6 signals via generation of alternate SMAD3 complexes that control the development of early signaling networks to potentiate the choice of Treg versus Th17 cell fate.  相似文献   

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Background

Chronic obstructive pulmonary disease (COPD) is a progressive and irreversible chronic inflammatory disease of the lung. The nature of the immune reaction in COPD raises the possibility that IL-17 and related cytokines may contribute to this disorder. This study analyzed the expression of IL-17A and IL-17F as well as the phenotype of cells producing them in bronchial biopsies from COPD patients.

Methods

Bronchoscopic biopsies of the airway were obtained from 16 COPD subjects (GOLD stage 1-4) and 15 control subjects. Paraffin sections were used for the investigation of IL-17A and IL-17F expression in the airways by immunohistochemistry, and frozen sections were used for the immunofluorescence double staining of IL-17A or IL-17F paired with CD4 or CD8. In order to confirm the expression of IL-17A and IL-17F at the mRNA level, a quantitative RT-PCR was performed on the total mRNA extracted from entire section or CD8 positive cells selected by laser capture microdissection.

Results

IL-17F immunoreactivity was significantly higher in the bronchial biopsies of COPD patients compared to control subjects (P < 0.0001). In the submucosa, the absolute number of both IL-17A and IL-17F positive cells was higher in COPD patients (P < 0.0001). After adjusting for the total number of cells in the submucosa, we still found that more cells were positive for both IL-17A (P < 0.0001) and IL-17F (P < 0.0001) in COPD patients compared to controls. The mRNA expression of IL-17A and IL-17F in airways of COPD patients was confirmed by RT-PCR. The expression of IL-17A and IL-17F was co-localized with not only CD4 but also CD8, which was further confirmed by RT-PCR on laser capture microdissection selected CD8 positive cells.

Conclusion

These findings support the notion that Th17 cytokines could play important roles in the pathogenesis of COPD, raising the possibility of using this mechanism as the basis for novel therapeutic approaches.  相似文献   

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Uncontrolled inflammation in systemic lupus erythematosus (SLE) could cause dysfunction in multiple organs. T helper 17 (Th17) cells are a main branch of inflammatory responses in the pathogenesis of SLE, and by producing interleukin 17 (IL-17), represent a major functional tool in the progression of inflammation. Animal models provide a special field for better studies of the pathogenesis of diseases. Tolergenic probiotics could decrease inflammation in autoimmune diseases by modulating the immune system and maintaining homeostasis. The aim of this project was to evaluate the effects of Lactobacillus rhamnosus and Lactobacillus delbrueckii on Th17 cells and their related mediators in a pristane-induced BALB/c mice model of SLE. The mice were divided into pretreatment groups, which received probiotics or prednisolone at Day 0, and treatment groups, which received probiotics and prednisolone 2 months after injection. The presence of antinuclear antibody (ANA), anti-double-stranded DNA (anti-dsDNA), and anti-ribonucleoprotein (anti-RNP) and lipogranuloma was evaluated; also, the population of Th1–Th17 cells as well as interferon γ (IFN-γ), IL-17, and IL-10 levels, and the expression of RAR-related orphan related receptor gamma (RORγt) and IL-17 were determined. We observed that probiotics and prednisolone could delay SLE in pretreatment and treatment mice groups, with a reduction in ANA, anti-dsDNA, anti-RNP, and mass of lipogranuloma. Probiotics and prednisolone decreased the population of Th1–Th17 cells and reduced IFN-γ and IL-17 as inflammatory cytokines in the pretreatment and treatment groups in comparison with SLE-induced mice. Our results indicated that, due to their anti-inflammatory properties and reduction of Th17, Th1, and cytotoxic T lymphocyte (CTL) cells, the use of these probiotics could probably represent a new tool for the better management of SLE.  相似文献   

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CD4+T cells differentiate into distinct functional effector and inhibitory subsets are facilitated by distinct cytokine cues present at the time of antigen recognition. Maintaining a balance between T helper 17 (Th17) and regulatory T (Treg) cells are critical for the control of the immunopathogenesis of liver diseases. Here, by using the mouse model of helminth Schistosoma japonicum (S japonicum) infection, we show that the hepatic mRNA levels of P21‐activated kinase 1 (PAK1), a key regulator of the actin cytoskeleton, adhesion and cell motility, are significantly increased and associated with the development of liver pathology during S japonicum infection. In addition, PAK1‐deficient mice are prone to suppression of Th17 cell responses but increased Treg cells. Furthermore, PAK1 enhances macrophage activation through promoting IRF1 nuclear translocation in an NF‐κB‐dependent pathway, resulting in promoting Th17 cell differentiation through inducing IL‐6 production. These findings highlight the importance of PAK1 in macrophages fate determination and suggest that PAK1/IRF1 axis‐dependent immunomodulation can ameliorate certain T cell–based immune pathologies.  相似文献   

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Aims

Extensive evidence suggests inflammatory components participate in the pathogenic processes of acute coronary syndromes (ACS). In this study, we aimed to elucidate the role and mechanism underlying the imbalance of Th17 and Treg cell peripheral populations in the pathogenesis of ACS.

Methods and Results

Using a flow cytometric analysis, we observed a significantly increased frequency of Th17 cells and a concurrently decreased CD4+CD25+Foxp3+ Treg cells in patients with ACS. To elucidate the mechanism of Th17/Treg imbalance in ACS, 22 inflammatory cytokines were measured using multiplexed immunobead-based assays. Of six elevated cytokines in ACS patients, only IL-6 was positively correlated with a higher Th17 cell level (r = 0.39, P<0.01). Relying on IL-6 stimulating and neutralizing studies, we demonstrated a direct role for IL-6 in sera from ACS patients with an increased frequency of Th17 cells. IL-6 induces the differentiation of Th17 cells from naïve CD4+ T cells through STAT3 activation and RORγt induction. However, we observed that high levels of TGF-β1 inhibited IL-6-dependent Th17 cell differentiation, indicating a complex interplay between the two cytokines in the control of Th17 and Treg cell populations.

Conclusions

Our results demonstrate the role of IL-6-STAT3 signaling in ACS through increased Th17 cell differentiation. These findings indicate that IL-6 neutralizing strategies could present novel therapeutic avenues in the treatment of ACS.  相似文献   

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Introduction

Serum interleukin (IL)-17 concentrations have been reported to be increased in systemic lupus erythematosus (SLE), but associations with clinical characteristics are not well understood. We characterized clinical associations of serum IL-17 in SLE.

Methods

We quantified IL-17 in serum samples from 98 SLE patients studied cross-sectionally, and in 246 samples from 75 of these patients followed longitudinally over two years. Disease activity was recorded using the SLE Disease Activity Index (SLEDAI)-2k. Serum IL-6, migration inhibitory factor (MIF), and B cell activating factor of the tumour necrosis factor family (BAFF) were also measured in these samples.

Results

Serum IL-17 levels were significantly higher in SLE patients compared to healthy donors (P <0.0001). No correlation was observed between serum IL-17 and SLEDAI-2k, at baseline or during longitudinal follow-up. However, we observed that SLEDAI-2k was positively correlated with IL-17/IL-6 ratio. Serum IL-17 was significantly increased in SLE patients with central nervous system (CNS) disease (P = 0.0298). A strong correlation was observed between serum IL-17 and IL-6 (r = 0.62, P <0.0001), and this relationship was observed regardless of disease activity and persisted when integrating cytokine levels over the period observed (r = 0.66, P <0.0001). A strong correlation of serum IL-17 was also observed with serum BAFF (r = 0.64, P <0.0001), and MIF (r = 0.36, P = 0.0016).

Conclusions

Serum IL-17 concentration correlates poorly with SLE disease activity but is significantly elevated in patients with CNS disease. IL-17/IL-6 ratio may be more useful than IL-17 or IL-6 alone to characterize Th17-driven disease, such as SLE. The association of other cytokines with serum IL-17 suggests that IL-17 may drive activation of diverse immune pathways in SLE.  相似文献   

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Impaired function of regulatory T-cells (Treg) leads to a failure in immune tolerance and triggers autoimmunity. We analyzed whether the deficiency in Treg in systemic lupus erythematosus (SLE) is accompanied by an increase in effector T-cell responses. We studied the frequencies of IL-17A (Th17) and IFNg (Th1) producing CD4(+) T-cells by flow cytometric detection of intracellular cytokines in PMA/ionomycin stimulated blood lymphocytes from seven patients with active SLE, eight with SLE in remission, and 11 healthy controls. Circulating Treg were evaluated as CD4(+)CD25(+) lymphocytes expressing FoxP3. There was no difference in the percentage of Treg cells between the groups, but their absolute counts were decreased in active SLE (5 [1-7] cells/μL) compared to inactive SLE (11 [6-15]; p = 0.05) and healthy controls (16 [10-20]; p 〈 0.01). Both the frequency and numbers of Th1 cells were decreased in SLE compared to controls. No difference was observed in the number of Th17 cells, which resulted in a decreased Th1/Th17 ratio. In parallel, a higher Treg/Th17 ratio in healthy controls (2.2 [1.8-3.6]) compared to active SLE (1.1 [1.0-2.1]; p 〈 0.05) was observed. There was a correlation between the number of Treg cells and disease activity status (SLEDAI, r = -0.59). SLE patients in the active phase of the disease are characterized by a deficiency in Treg cells and decreased Treg/Th17 ratio. This suggests that the imbalance between major T-cells subsets might be responsible for an increased proinflammatory response in the exacerbation of SLE.  相似文献   

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The imbalance of Th17/Treg cell populations has been suggested to be involved in the regulation of rheumatoid arthritis (RA) pathogenesis; however, the mechanism behind this phenomenon remains unclear. Recent studies have shown how microRNAs (miRNAs) are important regulators of immune responses and are involved in the development of a variety of inflammatory diseases, including RA. In this study, we demonstrated that the frequencies of CD3+CD4+IL‐17+Th17 cells were significantly higher, and CD4+CD25+FOXP3+ Treg cells significantly lower in peripheral blood mononuclear cells from RA patients. Detection of cytokines from RA patients revealed an elevated panel of pro‐inflammatory cytokines, including IL‐17, IL‐6, IL‐1β, TNF‐α and IL‐22, which carry the inflammatory signature of RA and are crucial in the differentiation and maintenance of pathogenic Th17 cells and dysfunction of Treg cells. However, the level of miR‐21 was significantly lower in RA patients, accompanied by the increase in STAT3 expression and activation, and decrease in STAT5/pSTAT5 protein and Foxp3 mRNA levels. Furthermore, lipopolysaccharide stimulation up‐regulated miR‐21 expression from healthy controls, but down‐regulated miR‐21 expression from RA patients. Therefore, we speculate that miR‐21 may be part of a negative feedback loop in the normal setting. However, miR‐21 levels decrease significantly in RA patients, suggesting that this feedback loop is dysregulated and may contribute to the imbalance of Th17 and Treg cells. MiR‐21 may thus serve as a novel regulator in T‐cell differentiation and homoeostasis, and provides a new therapeutic target for the treatment of RA.  相似文献   

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Restoring intestinal microbiota dysbiosis with fecal microbiota transplantation is considered as a promising treatment for ulcerative colitis. However, the mechanisms underlying its relieving effects remain unclear. Ulcerative colitis pathogenesis is associated with the involvement of immune cells and inflammatory cytokines. Here, we aimed to investigate the effect of fecal microbiota transplantation on T cell cytokines in a dextran sulfate sodium-induced ulcerative colitis mouse model. Five-aminosalicylic acid (5-ASA) was used as the positive control. Male C57BL/6 mice were randomly assigned to control, model (UC), UC + FMT, and UC + 5-ASA groups. Each group consisted of five mice. The establishment of the mouse model was verified by fecal occult-blood screening and hematoxylin–eosin staining. Results showed that fecal microbiota transplantation reduced colonic inflammation, significantly decreased T helper (Th)1 and Th17 cells, interferon-gamma, interleukin-2 and interleukin-17, as well as significantly increased Th2 and regulatory T (Treg) cells, interleukin-4, interleukin-10, and transforming growth factor-beta, and improved routine blood count. Furthermore, 16S rRNA gene-sequencing analysis showed a significant increase in the relative abundance of genus Akkermansia and a significant decrease in the relative abundance of genus Helicobacter in the ulcerative colitis group. Fecal microbiota transplantation restored the profile of the intestinal microbiota to that of the control group. These findings demonstrated the capability of fecal microbiota transplantation in controlling experimentally induced ulcerative colitis by improving Th1/Th2 and Th17/Treg imbalance through the regulation of intestinal microbiota.  相似文献   

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目的:探讨良性前列腺增生患者外周血Th17和Treg细胞比率的变化。方法:选择33例良性前列腺增生患者及19例正常对照者为研究对象,采用流式细胞术检测和比较其外周血中T淋巴细胞亚群及Th17和Treg细胞占CD4~+T细胞的比率。结果:良性前列腺增生患者外周血Th17和Treg细胞占CD4~+T细胞的比率分别为1.58±0.71和1.76±0.83,Th17/Treg的比率为0.89±0.42。正常健康对照者外周血Th17和Treg细胞占CD4~+T细胞的比率分别为0.75±0.46和1.83±0.75,Th17/Treg的比率为0.41±0.32。良性前列腺增生患者外周血Th17占CD4~+T细胞的比率和Th17/Treg的比率明显高于正常健康对照者(P0.05)。结论:良性前列腺增生患者体内Th17细胞比率升高,Th17/Treg比率失衡,可能与良性前列腺增生的发生、发展有关。  相似文献   

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Background

Typical and atypical optic neuritis (ON) are two clinical types of autoimmune inflammatory diseases of the optic nerve that causes acute vision loss, and are difficult to distinguish in their early stages. The disturbance in the balance of Th17 and Treg lymphocytes is thought to play an essential role in these autoimmune inflammatory diseases.

Objectives

To detect the clinical relevance of Th17 and Treg in peripheral blood and the ratio of Treg/Th17 in patients with typical and atypical ON. To determine whether analysis of Th17 and Treg lymphocytes will provides insights into the different disease phenotypes of typical and atypical ON.

Methods

We studied a consecutive series of patients aged 14–70 years who presented to our neurological department with typical ON (n = 30) or atypical ON (n = 33) within 4 weeks of their acute attacks. Routine clinical tests and ophthalmological examination were performed in all patients. Blood samples were collected from untreated patients and from gender- and age-matched healthy controls (n = 30). The proportion of peripheral blood Th17 cells and Treg cells was determined by flow cytometry.

Results

Patients with atypical ON had a higher proportion of Th17 cells than patients with typical ON (3.61±1.56 vs 2.55±1.74, P<0.01) or controls (1.45±0.86, P<0.01). The proportion of Th17 cells in patients with typical ON was also markedly higher than in controls (P<0.01). The mean percentage of Treg cells in atypical ON (6.31±2.11) and typical ON (6.80±2.00) were significantly lower when compared to controls (8.29±2.32, both P<0.01). No significant difference in Treg frequency was observed between typical ON and atypical ON (p>0.05).

Conclusions

The frequency of Th17 cells is higher in atypical ON than typical ON, and patients with atypical ON have a greater imbalance of pro-inflammatory and regulatory cells than patients with typical ON when compared with controls. These changes are indicative of distinct pathological mechanisms and may provide useful information to distinguish typical and atypical ON.  相似文献   

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This study aimed to explore the function of IFN‐γ+IL‐17+Th17 cells on fibrosis in systemic scleroderma (SSc). Blood and skin samples were collected from 20 SSc cases and 10 healthy individuals. The percentage of IFN‐γ+IL‐17+Th17 cells was detected using flow cytometry. The in vitro induction of IFN‐γ+IL‐17+Th17 cells was performed adopting PHA and rIL‐12. Gene expression was detected via quantitative real‐time polymerase chain reaction (qRT‐PCR), whereas western blot analysis was adopted for protein analysis. The distribution of IFN‐γ+IL‐17+Th17 cells was significantly increased in SSc cases and positively correlated with SSc stages (P = .031), disease duration (P = .016), activity (P = .025) and skin scores (P < .001). In vitro, IFN‐γ+IL‐17+Th17 cells could promote the expressions of α‐SMA and COL1A1, revealing increased fibroblasts’ proliferation and enhanced collagen‐secreting capacity. In addition, IL‐21 expression was significantly increased in co‐culture medium of IFN‐γ+IL‐17+Th17 cells and fibroblasts (P < .001). IL‐21 neutralizer treatment resulted in the down‐regulation of α‐SMA and COL1A1. IL‐21 was confirmed as an effector of IFN‐γ+IL‐17+Th17 cells in fibrosis process. The distribution of IFN‐γ+IL‐17+Th17 cells was significantly increased in SSc cases and positively correlated with disease activity. IFN‐γ+IL‐17+Th17 cells could promote fibroblast proliferation and enhance collagen‐secreting ability via producing IL‐21, thus contributing to fibrosis in SSc.  相似文献   

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目的:探讨妊娠梅毒患者外周血中Th17和Treg细胞水平及其临床意义。方法:选择2015年4月至2016年5月我院收治的35例妊娠梅毒患者作为观察组,并选择同期进行孕检的健康孕妇30例作为对照组。分析和比较其外周血Th17和Treg细胞水平及其诊断妊娠梅毒的临床价值。结果:观察组患者外周血Th17水平显著高于对照组,而外周血Treg水平显著低于对照组(P0.05)。多因素logistic回归分析结果显示外周血Th17和Treg水平与妊娠梅毒发病具有明显相关性。外周血Th17诊断妊娠梅毒的AUC为0.776,95%CI为0.656~0.896,外周血Treg诊断妊娠梅的ROC曲线下的面积(area under curve,AUC)为0.947,95%CI为0.897~997,Th17+Treg诊断妊娠梅毒的AUC为0.960,95%CI为0.913~1.000;Th17和Treg单独检测分别和联合检测曲线下面积比较均具有显著差异(Z=-2.807、-0.375,P0.05);Th17+Treg联合检测的特异度、准确度分别为91.73%、93.28%,显著高于各指标单独检测(P0.05)。结论:妊娠梅毒患者外周血Th17细胞增多,Treg细胞减少,联合检测外周血Th17和Treg细胞水平诊断妊娠梅毒具有较高的准确度,可作为诊断妊娠梅毒的重要参考指标。  相似文献   

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Purpose: Sulfur mustard (SM) lung is a heterogeneous disease associated with abnormal inflammatory immune responses. The Th17/Treg axis imbalance is associated with the pathogenesis of chronic inflammatory pulmonary disease. We aimed to determine the distribution of different Th17 and Treg cells in patients with SM lung and chronic obstructive pulmonary disease (COPD) and evaluate the clinical implications in this homeostasis. Methods: In this analytical cross-sectional study, CD4?+?Foxp3+?Treg and CD4+?IL-17+?Th17 cells were measured in peripheral blood mononuclear cells (PBMCs) and transbronchial biopsy (TBB) samples of 15 SM-exposed patients, 12 COPD and 13 healthy controls (HCs). The potential correlation between the ratio of Th17/Tregs and lung function was evaluated with multivariate logistic regression (MLR) analysis. Results: The frequency of CD4?+?FoxP3+?Tregs and CD4?+?IL-17+?Th17 was increased ~1.7-fold (8.71/4.95) and ~2.7-fold (1.028/0.371) respectively, in the PBMC of SM patients compared with the health controls (p?<?0.001). The results indicated that there were increases in the frequency of Th17 and Tregs cells in the patients with COPD versus the HC, that is, ~2.6-fold (0.987/0.371) and ~1.4-fold (7.12/4.95), respectively; but they did not reach to SM level (p?≥?0.05). Moreover, in the TBB samples, the CD4?+?IL-17+?Th17 and CD4+?FoxP3+?Tregs numbers were significantly higher in SM and COPD patients than HC (p?<?0.05). The Th17 and Treg cells were inversely correlated with forced expiratory volume in 1s (FEV1%) (r?=??0.351, p =?0.001; r?=??0.344, p?=?0.021) and FEV1/FVC (r?=??0.44, p?=?0.001; r?=??0.302, p?=?0.011), respectively. Instead, positive correlations were found between Treg/Th17 ratios and forced FEV1%pred (r?=?0.156, p?=?0.007), as well as FEV1/FVC ratio (r?=?0.334, p?=?0.006). Conclusions: The imbalance of Th17/Treg has a key role in immunopathogenesis of chronic phase of mustard lung disease.  相似文献   

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Th17细胞和Treg细胞是CD4+T细胞的新亚群,在分化发育、功能发挥的过程中受到Th1型、Th2型效应细胞以及自身分泌产生细胞因子的调节,参与自身免疫病、感染、肿瘤等疾病的发生发展。通过对Th17和Treg分化发育、和功能发挥过程中的关键调节因子进行阻断或加强,可以上调或下调Th17和Treg在疾病中的表达,以用于疾病的预防和诊治。  相似文献   

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目的探究子宫内膜异位症患者免疫调节Th17细胞及Treg细胞的表达意义。 方法选取2017年1月至2018年12月青岛大学附属医院收治患有子宫内膜异位症的患者,为子宫内膜异位组(EMT组),选取同一时期在医院因不孕不育进行腹腔镜检查的患者,为正常组(NM组),两组分别56例。EMT组和NM组患者在一般资料上差异无统计学意义。通过流式细胞仪、HE染色法、qRT-PCR法、ELISA法分析EMT组和NM组患者Th17、Treg细胞所占比例、子宫内膜组织病变情况、ROR-γt、Foxp3 mRNA表达含量的差异性来探究子宫内膜异位症患者Th17细胞及Treg细胞变化。实验结果用 ±s表示,并采用独立样本t检验进行比较。 结果EMT组患者CD4+ T细胞中Th17所占比例为5.48±2.81,Treg所占比例为4.22±1.04,NM组Th17所占比例为2.34±1.01,Treg所占比例为6.14±1.52,差异均有统计学意义(t = 7.869,3.015,P = 0.014,0.026)。EMT组患者血清中IL-17水平为(256.38±34.15)?pg/ ml、IL-22为(67.48±10.89)?pg/ml,NM组患者血清中IL-17水平为(198.04±27.59)?pg/ml、IL-22为(43.78±6.92)?pg/ml,差异均有统计学意义(t = 9.944,4.689,P = 0.008,0.017)。EMT组患者血清中IL-10水平为(18.56±4.77)?pg/ml、TGF-β为(148.28±40.52) pg/ ml,NM组患者血清中IL-10水平为(28.35±6.07)pg/ml、TGF-β为(204.78±19.87)pg/ml,差异均有统计学意义(t = 9.491,2.849,P = 0.012,0.034)。EMT组患者子宫内膜组织形态不规则,多数细胞不完整,破损或缺失,且炎性细胞增多,在其周围聚集。NM组患者子宫内膜组织形态规则,细胞没有明显破损或缺失,未见细胞周围炎性因子增多。qRT-PCR检测结果显示,EMT组和NM组ROR-γ mRNA分别为2.89±0.76、1.71±0.26,EMT组和NM组Foxp3 mRNA分别为2.25±0.34、1.13±0.18,两组差异均有统计学意义(t = 10.996,6.759,P = 0.006,0.011)。 结论子宫内膜异位症患者外周血免疫调节细胞Th17/Treg平衡失调,免疫调节紊乱与子宫内膜异位发生、发展有密切关系。  相似文献   

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