Treg/Th17细胞分化失衡与炎症性肠病

炎症性肠病（IBD）的病因和发病机制尚未完全明确,初始CD4~＋T细胞分化异常在其发生、发展过程中起重要作用。初始CD4~＋T细胞可分化为调节性T细胞（Treg细胞）和Th17细胞,Treg/Th17细胞间的失衡将导致包括IBD在内的多种自身免疫病的发生。初始CD4~＋T细胞周围的细胞因子和芳香烃受体对维持该平衡起重要作用。本文就Treg细胞和Th17细胞及其与IBD的关系作一综述。     

T辅助细胞在炎症性肠病免疫发病机制中的研究进展

炎症性肠病(IBD)包括克罗恩病(CD)和溃疡性结肠炎(UC),免疫机制在其发病中的作用近年来受到密切关注,而T淋巴细胞中的T辅助细胞(Th),其亚型Th1、Th2、Th17、Treg和它们分泌的细胞因子在免疫调节炎症中发挥了至关重要的作用.此文就目前国内外关于Th细胞在IBD的免疫发病机制中的研究现状作一综述.     

调节Th17/Treg细胞平衡的因素及其对炎症性肠病的影响

在炎症性肠病(inflammatory bowel disease, IBD)中,自身免疫由辅助性T细胞17(T helper cell 17, Th17)细胞驱动并被调节性T细胞(regulatory cells, Tregs)抑制,因此重塑Th17/Treg细胞的平衡对于治疗IBD至关重要.有许多因素参与影响了Th17/Treg平衡,其中包括TCR信号,共刺激信号,细胞因子信号,代谢水平,微生物群等.下面,本文将讲述它们在调节Th17/Treg平衡中的作用以及对IBD的影响.     

Th17细胞在炎症性肠病发病中的作用

炎症性肠病(IBD)是一类慢性炎症性消化道疾病,包括克罗恩病(CD)和溃疡性结肠炎(UC)。IBD的病因和发病机制尚未完全明确,其中免疫功能紊乱在IBD发病中占据关键地位。Th17细胞是能特异性产生IL-17的CD4~+T细胞,近年研究证实其在IBD异常免疫反应中发挥重要作用。本文就Th17细胞在IBD发病中的作用作一综述。     

调节性T细胞及其分化因子IL-10治疗炎症性肠病的研究进展

CD+4 T细胞在炎症性肠病发病机制中起重要作用 ,Th1细胞因子介导的炎症病理改变类似于克罗恩病 ;Th2细胞因子介导的炎症病理改变类似于溃疡性结肠炎。在分化因子IL 10的作用下 ,调节性T细胞 (Tr1)又可分泌高水平的IL 10 ,通过旁观者抑制机制 ,抑制肠道粘膜免疫病理性损伤 ,达到治疗炎症性肠病的目的。     

Treg细胞和Th17细胞在炎症性肠病治疗中的作用

炎症性肠病(IBD)是一类非特异性肠道炎症性疾病,肠道黏膜免疫失衡是诱导IBD发生的主要原因之一。调节性T细胞(Treg细胞)是重要的免疫调控细胞,辅助性T细胞17(Th17细胞)参与宿主免疫防御,两者之间的平衡是维持肠道免疫稳态的重要因素。本文就Treg细胞和Th17细胞在IBD治疗中的作用作一综述。     

Th17/Treg失衡与炎症性肠病的关系

炎症性肠病(inflammatory bowel disease.IBD)的病因和发病机制尚未完全明确,肠道黏膜免疫系统异常反应所导致的炎症过程在发病中起重要作用.辅助性T细胞17(T helper 17 cells,Th17)可介导慢性炎症和自身免疫性疾病的发生,调节性T细胞(regulatory T cell,Treg)有抑制自身免疫的功能,二者存在相互转化的关系.有研究表明Th17/Treg转化平衡是维持肠道免疫稳态的重要因素,这可能是导致人类IBD的原因之一.最近研究表明TGF-β,IL-6和维甲酸(retinoic acid,RA)可能是调控二者平衡关系的重要因素.肠道菌群(intestinal flora)与IBD的发生发展关系密切,益生菌(probiotics)对IBD的治疗作用成为研究的热点.深化对Th17/Treg转化调控关系的研究是当前重要的研究课题.     

调节性T细胞及其分化因子IL-10治疗炎症性肠病的研究进展

CD^ 4T细胞在炎症性肠病发病机制中起重要作用，Th1细胞因子介导的炎症病理改变类似于克罗恩病；Th2细胞因子介导的炎症病理改变类似于溃疡性结肠炎。在分化因子IL-10的作用下，调节性T细胞(Trl)又可分泌高水平的IL-10，通过旁观者抑制机制，抑制肠道粘膜免疫病理性损伤，达到治疗炎症性肠病的目的。     

Th17细胞及肠道内共生菌群在炎症性肠病中的作用

炎症性肠病(inflammatory bowe ldisease,IBD)是一种以慢性肠道炎症性疾病,病因未明,肠道黏膜异常的免疫反应在发病中有着重要作用.最近发现一类辅助T淋巴细胞Th17细胞,能在肠黏膜中大量分泌IL-17A和IL-17F.减少肠道Th17细胞数量和其相关的细胞因子的表达能够缓解肠道炎症反应,预示Th17细胞在IBD发病中起到一定作用.肠道共生菌与IBD的发病也有着密切关系,肠道共生菌群的变化可能导致Th17细胞的数量发生改变引起炎症,或者通过其他机制和途径诱发免疫紊乱,从而使得炎症得以发生.本文就Th17细胞的分化与其在IBD中的作用,以及共生菌群和Th17细胞之间的相互联系作一综述.     

Th17细胞及IL-23在炎症性肠病中的研究进展

炎症性肠病(IBD)是一种病因和发病机制尚不清楚的发生在胃肠道的慢性非特异性炎症性疾病。大量证据表明先天性和获得性免疫系统的异常均对该疾病起着关键性作用。传统观点认为炎症性肠病与Th1细胞和Th2细胞所介导的免疫应答有关;但最新研究指出,体内Th17细胞以及白细胞介素IL-23的存在,与炎症性肠病的发生息息相关。本文对炎症性肠病中Th17细胞及IL-23的研究进展作一综述。     

Dysregulation of mucosal immune response in pathogenesis of inflammatory bowel disease

Inflammatory bowel disease(IBD)includes Crohn’s disease and ulcerative colitis.The exact etiology and pathology of IBD remain unknown.Available evidence suggests that an abnormal immune response against the microorganisms in the intestine is responsible for the disease in genetically susceptible individuals.Dysregulation of immune response in the intestine plays a critical role in the pathogenesis of IBD,involving a wide range of molecules including cytokines.On the other hand,besides T helper(Th)1 and Th2 cell immune responses,other subsets of T cells,namely Th17 and regulatory T cells,are likely associated with disease progression.Studying the interactions between various constituents of the innate and adaptive immune systems will certainly open new horizons of the knowledge about the immunologic mechanisms in IBD.     

Role of cytokines in inflammatory bowel disease

Inflammatory bowel disease （IBD）, which includes Crohn’s disease （CD） and ulcerative colitis （UC）, rep- resents a group of chronic disorders characterized by inflammation of the gastrointestinal tract, typically with a relapsing and remitting clinical course. Mucosal mac- rophages play an important role in the mucosal im- mune system, and an increase in the number of newly recruited monocytes and activated macrophages has been noted in the inflamed gut of patients with IBD. Activated macrophages are thought to be major con- tributors to the production of inflammatory cytokines in the gut, and imbalance of cytokines is contributing to the pathogenesis of IBD. The intestinal inflammation in IBD is controlled by a complex interplay of innate and adaptive immune mechanisms. Cytokines play a key role in IBD that determine T cell differentiation of Th1, Th2, T regulatory and newly described Th17 cells. Cytokines levels in time and space orchestrate the development, recurrence and exacerbation of the inflammatory process in IBD. Therefore, several cyto- kine therapies have been developed and tested for the treatment of IBD patients.     

The Interleukin-23 / Interleukin-17 axis in intestinal inflammation

Although the precise aetiology of inflammatory bowel disease (IBD) remains unclear, recent discoveries have led to an improved understanding of disease pathogenesis. Whilst these findings have underscored the central role of innate and adaptive immune responses in intestinal inflammation, they have also precipitated a paradigm shift in the key cytokine pathways that drive disease. The prevailing dogma that IBD was mediated by interleukin (IL)-12-driven T-helper (Th)1 CD4 T cell responses towards the bacterial flora has been largely dispelled by findings that the closely related cytokine IL-23 appears to be the key mediator of intestinal inflammation. IL-23 is associated with a novel subset of IL-17-secreting CD4 T cells termed Th17 cells and rodent studies have implicated the IL-23/IL-17 axis in autoimmune inflammation. Genome-wide association studies in IBD patients have confirmed the predominant role of the IL-23 pathway, indicating that this could represent an important future therapeutic target.     

Old and New Lymphocyte Players in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), encompassing Crohn’s disease and ulcerative colitis, is a chronic intestinal inflammatory disorder characterized by diffuse accumulation of lymphocytes in the gut mucosa as a consequence of over-expression of endothelial adhesion molecules. The infiltrating lymphocytes have been identified as subsets of T cells, including T helper (Th)1 cells, Th17 cells, and regulatory T cells. The function of these lymphocyte subpopulations in the development of IBD is well-known, since they produce a number of pro-inflammatory cytokines, such as interferon-γ and interleukin-17A, which in turn activate mucosal proteases, thus leading to the development of intestinal lesions, i.e., ulcers, fistulas, abscesses, and strictures. However, the immune mechanisms underlying IBD are not yet fully understood, and knowledge about the function of newly discovered lymphocytes, including Th9 cells, innate lymphoid cells, mucosal-associated invariant T cells, and natural killer T cells, might add new pieces to the complex puzzle of IBD pathogenesis. This review summarizes the recent advances in the understanding of the role of mucosal lymphocytes in chronic intestinal inflammation and deals with the therapeutic potential of lymphocyte-targeting drugs in IBD patients.     

CD4+CD25+调节性T细胞在哮喘发生发展中的作用研究进展

支气管哮喘被普遍认为是因Th1／Th2失衡，由过度激活的Th2细胞介导的气道炎症性疾病。然而，Th1／Th2理论并不能充分阐明哮喘的发病机制。近几年来，越来越多的证据显示调节性T细胞在哮喘的发生发展中起到很重要的作用，CD4^＋CD25^＋调节性T细胞作为调节性T细胞的一种亚型成为目前研究的热点。本文就近来对CD4^＋CD25^＋调节性T细胞研究的进展及其与哮喘的关系作一综述。     

Inflammatory bowel disease,past, present and future: lessons from animal models

Accumulating data from animal models indicate that Inflammatory bowel disease (IBD) is mediated by a much more complicated mechanism than previously predicted. For example, the role of an individual molecule in the pathogenesis of IBD distinctly differs depending on several factors, including the fundamental mechanism of induction of the disease, the target cell type, the phase of disease, and the environment. Therefore, it has been difficult in the past to fully explain the complicated mechanism. Novel concepts have recently been proposed to further explain the complicated mechanism of IBD. In this review, we introduce past, current, and possible future concepts for IBD models regarding T helper (Th) 1, Th2, and Th17, antigen sampling and presentation, regulatory cell networks, NOD2, Toll-like receptors, bacteria/epithelia interaction, stem cells, autophagy, microRNAs, and glycoimmunology, and we also discuss the relevance of these new concepts, developed at the bench (in animal models), to the bedside.     

Th17细胞／调节性T细胞平衡与自身免疫性肝病

最新研究发现了与Th1和Th2细胞亚群不同的新的活化CD4^＋T细胞亚群——调节性T细胞（Treg细胞）和Th17细胞,两者在发育和功能上互补,Th17细胞／Treg细胞平衡在自身免疫性肝病的发生、发展中发挥重要作用。本文就Th17细胞／Treg细胞平衡在自身免疫性肝病中的作用作一综述。     

肌成纤维细胞在支气管哮喘气道结构重塑中的作用

肌成纤维细胞兼具成纤维细胞和平滑肌细胞的某些特征,来源于局部细胞的增殖,其他细胞的转化及循环中前体细胞的定植,在疤痕形成、肺纤维化等病理过程中发挥重要作用。研究显示其受支气管哮喘相关炎症因子及介质的调控,通过分泌细胞外基质及迁移功能而参与支气管哮喘气道重塑。深入了解肌成纤维细胞在支气管哮喘气道重塑中的作用有助于建立防治气道重塑的新策略。