哮喘大鼠模型信号转导子和转录激活子6在气道上皮细胞表达增强

目的探讨哮喘大鼠肺组织中信号转导子和转录激活子6(STAT6)的活化规律及其意义。方法将SD大鼠随机分为对照组和哮喘组,后者根据末次激发后处死时相不同分成0、3、8、24、72、120和144 h组。采用透射电镜、细胞计数、免疫组化和图像分析等,分别观察肺组织超微结构、支气管肺泡灌洗液(BALF)中嗜酸性粒细胞(EOS)数量及STAT6蛋白表达。结果①哮喘组肺组织EOS炎性浸润较对照组明显增加;②哮喘组STAT6蛋白主要在气道上皮细胞表达;③3 h时STAT6即开始明显升高,24 h达到峰值,其后有所下降;④STAT6蛋白表达的变化与BALF中EOS绝对值及EOS%的动态变化均显著正相关(P<0.01)。结论哮喘大鼠气道上皮细胞存在STAT6的持续活化及过度表达,并与EOS的生成密切相关,提示STAT6的活化在哮喘气道炎症调控中起重要作用。     

丙型肝炎病毒核心蛋白与信号转导及转录活化蛋白3的相互作用

为了观察丙型肝炎病毒(HCV)核心蛋白(CORE)对信号转导及转录活化蛋白3(STAT3)表达的影响,寻找CORE与STAT3相互作用的功能区域。对Huh-7、转染表达CORE的Huh-7和含有全长HCV基因的复制子(Replicon)Huh-7的STAT3及磷酸化STAT3(p-STAT3)表达水平作比较;并对CORE与STAT3进行免疫共沉淀试验、谷胱甘肽S转移酶(GST)结合试验。结果显示,CORE能直接结合并诱导STAT3和p-STAT3表达,不同病毒株CORE及CORE不同功能区域结合STAT3和p-STAT3能力不同,CORE结合于STAT3主要依耐于CORE的N端的1~126氨基酸。因此,CORE与STAT3的相互作用可能是HCV感染又一新的分子致病机制,在引起HCV持续感染和肝细胞癌的发病机制中起重要作用。     

Human TH9 differentiation is dependent on signal transducer and activator of transcription (STAT) 3 to restrain STAT1-mediated inhibition

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脂多糖刺激干扰素调节因子3促进小鼠腹腔巨噬细胞白介素-17表达

目的：探讨干扰素调节因子3（IRF3）对脂多糖（LPS）刺激小鼠腹腔巨噬细胞促进白细胞介素-17（IL-17） 表达的初步作用机制。方法：小鼠腹腔注射3%巯基乙酸肉汤,3 d 后提取C57BL/6 野生和IRF3 基因敲除小鼠的 腹腔巨噬细胞,培养过夜后添加LPS。收集细胞培养上清液,酶联免疫吸附试验检测细胞因子IL-17 和白细胞介素-6 （IL-6）的表达;提取细胞蛋白质,免疫印迹检测细胞核因子κB抑制蛋白（IκB）α、IRF3、磷酸化信号转导子和 转录激活子3（STAT3）的蛋白水平。结果：LPS 刺激小鼠腹腔巨噬细胞后,IRF3 可显著地促进IL-17 的产生,同 时伴随着IL-6 的产生、IκBα 蛋白的降解及STAT3 的磷酸化。结论：IRF3 可能通过促进IL-6 的产生,间接地激活 STAT3 的磷酸化,进而促进IL-17 的产生。     

乳腺癌患者原发磷酸化信号转导与转录激活因子3活性和白细胞介素-17表达的临床意义

目的 探讨炎性信号通路磷酸化信号转导和转录激活因子3（p-STAT）的原发活化状态及下游细胞因子白细胞介素（IL）-17表达在乳腺癌发生和发展中的作用及其对预后的影响。 方法 运用免疫组织化学Envision两步法检测了379例乳腺癌患者以及匹配癌旁245例乳腺腺病中IL-17表达和原发性p-STAT3的活化状态,分析了它们与乳腺癌组织学分型、TNM分期、临床分期及预后的相关性。统计学分析：计量数据使用t检验法,计数数据使用χ2 检验法。结果 1. IL-17在乳腺癌中的阳性表达率为95.8%,显著高于乳腺腺病中的阳性表达率85.3%（χ2=21.363,P<0.001）;具有活性的p-STAT3在乳腺癌中的阳性率为93.6%,也显著高于乳腺腺病中的阳性率62.0%（χ2=97.702,P<0.001）。2. IL-17和p-STAT3在乳腺癌 (包括乳腺浸润性导管癌、乳腺浸润性小叶癌和腺导管原位癌分型) 中的阳性率与乳腺癌组织学分型无相关性（χ2=1.245, P=0.535＞0.05）。3. IL-17和p-STAT3在乳腺癌中的强阳性率分别与淋巴结的转移成正相关（IL-17: χ2=7.806, P<0.01; p-STAT3: χ2=4.053, P<0.05）。4. 在乳腺癌组织中,IL-17表达与p-STAT3活性呈正相关（rs=0.136, P<0.01）。 结论 原发增高的p-STAT3活性及高表达的炎性细胞因子IL-17可能协同作用,产生炎性微环境,从而参与乳腺癌的发生和发展。     

信号转导子和转录激活子6及其mRNA在哮喘大鼠气道炎症中的作用

目的：探讨信号转导子和转录激活子6(STAT6)及其mRNA在哮喘大鼠气道炎症中的作用。 方法： 20只二级雄性SD大鼠随机分为2组, 对照组和哮喘组。以卵清白蛋白(OVA) 致敏激发法复制大鼠哮喘模型，每只大鼠左肺留取肺组织，右肺进行支气管肺泡灌洗并留取支气管肺泡灌洗液(BALF)。对BALF进行细胞总数、嗜酸性粒细胞(EOS)计数和分类计数；应用双抗体夹心酶联免疫吸附试验（Sandwich ELISA）法测定BALF和血清中IL-4浓度；采用免疫组化法和原位杂交法测定STAT6蛋白和STAT6 mRNA的表达情况。 结果： (1) BALF和血清中白细胞介素4(IL-4)的浓度哮喘组均显著高于对照组(均P<0.01)；(2)免疫组化和原位杂交显示，哮喘组支气管STAT6蛋白和STAT6 mRNA的表达均显著高于对照组(均P<0.01)，其主要表达细胞是上皮细胞；(3)支气管上皮细胞STAT6蛋白及其mRNA含量分别与BALF中的IL-4浓度、EOS绝对值呈非常显著正相关。 结论： 哮喘大鼠STAT6蛋白和mRNA高表达，上皮细胞是其主要表达细胞，并与IL-4浓度、EOS募集密切相关。     

Desmoglein 3-specific T regulatory 1 cells consist of two subpopulations with differential expression of the transcription factor Foxp3

Pemphigus vulgaris (PV) is an autoimmune bullous skin disorder associated with autoantibodies against desmoglein (Dsg) 3. An imbalance of type 1 regulatory T (Tr1) cells and T helper type 2 (Th2) cells specific for Dsg3 may be critical for the loss of tolerance against Dsg3 in PV. Within the population of Dsg3-responsive, interleukin (IL)-10-secreting Tr1 cell clones, two major subpopulations were identified and sorted by fluorescence-activated cell sorting (FACS) based on their size and granularity. Upon in vitro culture, the larger subpopulation differentiated back into the two former subpopulations of the Tr1 cell clones, while the smaller subpopulation died within 2 weeks. The smaller subpopulation of the Tr1 cell clones was characterized by the expression of Foxp3, the secretion of IL-10, transforming growth factor (TGF)-beta and IL-5 upon stimulation with Dsg3, a proliferative response to IL-2 but not to Dsg3 or mitogenic stimuli, and an inhibitory effect on the proliferative response of Dsg3-responsive Th clones in a Dsg3-specific manner. In contrast, the larger subpopulation showed a Th-like phenotype, lacking Foxp3, cytotoxic T-lymphocyte antigen 4 (CTLA4) and glucocorticoid-induced tumour necrosis factor receptor (GITR) expression and IL-2 secretion, and did not mount a proliferative response to Dsg3 and mitogenic stimuli. The two Tr1 subpopulations showed expression of identical T-cell receptor (TCR) V beta chains which varied among the PV patients studied. Upon inhibition of Foxp3, the smaller Tr1 subpopulation developed a proliferate response to Dsg3 and mitogenic stimuli, no longer suppressed Dsg3-specific Th cells, lost expression of GITR and CTLA4 and secreted IL-2. Thus, our observations suggest a distinct relationship between Dsg3-specific Tr1 and Th-like cells which may be critical for the continuous generation and survival of Dsg3-specific Tr1 cells.     

Emerging possibilities in the development and function of regulatory T cells

CD25+CD4+ Regulatory T cells (Treg) represent a unique population of lymphocytes capable of powerfully suppressing immune responses. A large body of experimental data have now confirmed the essential role played by these cells in a host of clinically relevant areas such as self-tolerance, transplantation, allergy and tumor/microbial immunity. Despite this mass of knowledge, significant gaps in our understanding of fundamental Treg biology remain, particularly regarding their development and mechanisms of suppression. In this review we attempt to highlight the current controversies and directions in which this exciting field is moving.     

SHARPIN controls the development of regulatory T cells

SHARPIN is an essential component of the linear ubiquitin chain assembly complex (LUBAC) complex that controls signalling pathways of various receptors, including the tumour necrosis factor receptor (TNFR), Toll‐like receptor (TLR) and antigen receptor, in part by synthesis of linear, non‐degrading ubiquitin chains. Consistent with SHARPIN's function in different receptor pathways, the phenotype of SHARPIN‐deficient mice is complex, including the development of inflammatory systemic and skin diseases, the latter of which depend on TNFR signal transduction. Given the established function of SHARPIN in primary and malignant B cells, we hypothesized that SHARPIN might also regulate T‐cell receptor (TCR) signalling and thereby control T‐cell biology. Here, we focus primarily on the role of SHARPIN in T cells, specifically regulatory T (Treg) cells. We found that SHARPIN‐deficient (Sharpin^cpdm/cpdm) mice have significantly reduced numbers of FOXP3⁺ Treg cells in lymphoid organs and the peripheral blood. Competitive reconstitution of irradiated mice with mixed bone marrow from wild‐type and SHARPIN‐deficient mice revealed an overall reduced thymus population with SHARPIN‐deficient cells with almost complete loss of thymic Treg development. Consistent with this cell‐intrinsic function of SHARPIN in Treg development, TCR stimulation of SHARPIN‐deficient thymocytes revealed reduced activation of nuclear factor‐κB and c‐Jun N‐terminal kinase, establishing a function of SHARPIN in TCR signalling, which may explain the defective Treg development. In turn, in vitro generation and suppressive activity of mature SHARPIN‐deficient Treg cells were comparable to wild‐type cells, suggesting that maturation, but not function, of SHARPIN‐deficient Treg cells is impaired. Taken together, these findings show that SHARPIN controls TCR signalling and is required for efficient generation of Treg cells in vivo, whereas the inhibitory function of mature Treg cells appears to be independent of SHARPIN.