microRNA对免疫细胞的调节作用

微小RNA(microRNA,miRNA)是一类可以直接作用于目的基因mRNA以调节相应功能蛋白的表达进而参与各种生理反应的小分子RNA,近年来受到广泛关注。本文主要综述了miRNA对免疫细胞的调节作用,包括造血干细胞、固有免疫细胞和适应性免疫细胞。miRNA不仅可以调节造血干细胞的发育,还可以调节巨噬细胞、树突状细胞、肥大细胞、T淋巴细胞和B淋巴细胞的发育和功能。此外,miRNA还能参与病毒感染、癌症、肿瘤和自身免疫性疾病的发生。     

胸腺基质淋巴细胞生成素对免疫细胞的调控作用及其研究进展

胸腺基质淋巴细胞生成素(thymic stromal lymphopoietin, TSLP), 作为一种多效性的细胞生长因子, 不仅参与人体皮肤纤维化、表皮增生以及血管生成等过程, 同时还对免疫相关疾病(如呼吸系统疾病、过敏性疾病等)中多种免疫细胞具有调控作用, 是免疫细胞的关键调控因子。TSLP主要通过TSLP受体介导的JAK/STAT、NF-κB等信号通路, 参与调控多种固有免疫细胞(如树突状细胞、肥大细胞、巨噬细胞、嗜酸性粒细胞、嗜碱性粒细胞、自然杀伤性T细胞、固有淋巴细胞)以及适应性免疫应答细胞(T和B淋巴细胞等)的分化、增殖过程与功能。现就近年来TSLP对多种免疫细胞增殖、分化及功能的调控研究进展作一综述。     

固有免疫细胞在宿主抗烟曲霉免疫中的作用

烟曲霉是一种环境中丝状真菌, 也是一种机会致病菌, 其感染宿主后能够引起慢性曲霉病和侵袭性曲霉病。曲霉病的发生发展是宿主与病原体相互作用的结果, 免疫状态不同的患者感染曲霉后临床症状存在差异。宿主对吸入真菌孢子的固有免疫应答是曲霉病发生的关键决定因素。本综述主要总结了目前对烟曲霉孢子侵入后宿主固有免疫细胞防御真菌感染的作用, 包括巨噬细胞、中性粒细胞、自然杀伤细胞、自然杀伤T细胞及肥大细胞, 为曲霉感染的致病机制解析、临床防治等相关研究提供一定的参考。     

T-bet和Eomes对细胞免疫功能的调控作用

T-box expressed in T cells(T-bet)和Eomesodermin(Eomes)是调控I型效应T细胞的重要转录因子,对CD4I型辅助T细胞(Th1细胞)、NK细胞、CD8+细胞毒T淋巴细胞(CTL)等的分化发育和功能调控有重要作用。机体的抗肿瘤免疫主要依赖T淋巴细胞介导的适应性免疫应答和NK细胞介导的固有免疫应答。T-bet和Eomes通过调控这些免疫细胞影响抗肿瘤免疫应答,对肿瘤的发生、发展及转归有重要意义。     

低温治疗通过p38 MAPK信号通路抑制UVB诱导的小鼠皮肤炎症北大核心CSCD

目的探讨局部低温治疗对中波紫外线辐射(UVB)诱导的皮肤炎症的作用机制。方法角质形成细胞体外培养后接受如下3种处理:仅低温治疗、仅UVB照射、UVB照射后低温治疗,检测低温治疗对UVB照射后角质形成细胞的作用。将野生型雌性C57BL/6小鼠分为3组:低温治疗组、UVB组、UVB+低温治疗组。通过数字测微计测量、组织病理学、免疫组织化学、免疫荧光、定量RT-PCR和Western blot检测低温治疗对UVB诱导炎症的影响。结果低温治疗可显著减少UVB诱导的巨噬细胞和T细胞浸润(P<0.05),并显著抑制UVB诱导的p38磷酸化(P<0.05),减少相关的炎症反应,包括减轻耳肿胀反应、表皮增生(P<0.05)和皮肤炎症(P<0.05),减少小鼠模型中相关细胞因子表达和细胞凋亡(P<0.05)。结论低温治疗是治疗UVB诱导的皮肤炎症的一种有效的方法。     

自然杀伤细胞的基础研究和进展

人们对免疫系统的认识早已从单一的线性结构到充满着反馈性因素的网络结构,代表着固有免疫细胞的NK细胞是淋巴细胞中具有重要意义的第三类亚群.NK细胞具有特征性的功能包括杀伤病毒感染细胞或变异的肿瘤细胞,因而被称之为溶细胞性效应细胞,并且还有重要的分泌细胞因子和趋化因子功能,是固有免疫中重要的组成部分.     

肠道黏膜免疫

肠道免疫系统由大量弥散分布在肠黏膜上皮内和固有层的免疫细胞和免疫分子、以及诸如peyer’spatches(PP)等肠相关性淋巴组织等组成。小肠PP结为肠黏膜免疫主要诱导部位,肠黏膜上皮和固有层为主要效应部位。B细胞、T细胞在PP结诱导后,分化、成熟,并移行到黏膜效应部位,发挥免疫效应功能。     

紫外线与皮肤免疫

皮肤作为一个独立的免疫器官,在紫外线(UV)照射下可以引起一系列的炎症反应和免疫学效应.在过去的30年中,紫外线诱导皮肤免疫抑制一直是光学免疫领域的研究热点,本文就紫外线对皮肤免疫系统的影响作一综述.     

免疫负调控因子TIPE2在自身免疫性疾病发病过程中的作用及机制研究进展

自身免疫性疾病是由于机体免疫系统对自身组织和器官发生了免疫应答并造成组织损伤和功能障碍的一类疾病,约占全世界人口的5％～10％.多种器官特异性自身免疫性疾病主要是由T细胞介导的,此外,其它的免疫细胞,如B细胞、T调节细胞、树突状细胞和巨噬细胞等在自身免疫性疾病的发生过程中也起着非常重要的作用.肿瘤坏死因子α诱导蛋白8-2(TNFAIP8L2或TIPE2)是2008年发现的免疫负调控因子,主要在免疫细胞中表达,通过对固有免疫和适应性免疫进行负性调控,从而维持体内环境稳定,实现免疫耐受.最近的研究发现,TIPE2在自身免疫性疾病的发病过程中起着非常重要的作用.     

紫外线激活Ts细胞的机制

紫外线对皮肤的作用是多种多样的。紫外线(UV)对皮肤的致病作用包括致癌、使皮肤老化、提高皮肤对光敏感性和抑制皮肤免疫功能。过量的紫外线照射既能促使表皮细胞癌变,又可抑制皮肤的免疫力。目前已知紫外线引起的免疫抑制包括局部皮肤免     

Deconstructing deployment of the innate immune lymphocyte army for barrier homeostasis and protection

The study of the immune system has shifted from a purely dichotomous separation between the innate and adaptive arms to one that is now highly complex and reshaping our ideas of how steady-state health is assured. It is now clear that immune cells do not neatly fit into these two streams and immune homeostasis depends on continual dialogue between multiple lineages of the innate (including dendritic cells, innate lymphoid cells, and unconventional lymphocytes) and adaptive (T and B lymphocytes) arms together with a finely tuned synergy between the host and microbes which is essential to ensure immune homeostasis. Innate lymphoid cells are critical players in this new landscape. Here, we discuss recent studies that have elucidated in detail the development of ILCs from their earliest progenitors and examine factors that influence their identification and ability to drive immune homeostasis and long-term immune protection.     

Harnessing human dendritic cell subsets for medicine

Summary: Immunity results from a complex interplay between the antigen-non-specific innate immune system and the antigen-specific adaptive immune system. The cells and molecules of the innate system employ non-clonal recognition receptors including lectins, Toll-like receptors, NOD-like receptors, and helicases. B and T lymphocytes of the adaptive immune system employ clonal receptors recognizing antigens or their derived peptides in a highly specific manner. An essential link between innate and adaptive immunity is provided by dendritic cells (DCs). DCs can induce such contrasting states as immunity and tolerance. The recent years have brought a wealth of information on the biology of DCs revealing the complexity of this cell system. Indeed, DC plasticity and subsets are prominent determinants of the type and quality of elicited immune responses. In this article, we summarize our recent studies aimed at a better understanding of the DC system to unravel the pathophysiology of human diseases and design novel human vaccines.     

Novel innate and adaptive lymphocytes: The new players in the pathogenesis of inflammatory upper airway diseases

Host immunity (innate and adaptive immunity) plays essential roles in the pathogenesis of inflammatory upper airway diseases, including allergic rhinitis and chronic rhinosinusitis. Recently, the discovery of novel innate immune cells, particularly innate lymphoid cells, has renewed our view on the role of innate immunity in inflammatory upper airway diseases. Meanwhile, the identification of new subsets of T helper (Th) cells, including Th22, Th9 and follicular Th cells, and regulatory B cells in the adaptive immunity, has broadened our knowledge on the complex immune networks in inflammatory upper airway diseases. In this review, we focus on these newly identified innate and adaptive lymphocytes with their contributions to the immunological disturbance in allergic rhinitis and chronic rhinosinusitis. We further discuss the perspective for future research and potential clinical utility of regulating these novel lymphocytes for the treatment of allergic rhinitis and chronic rhinosinusitis.     

The evolutionary arms race between NK cells and viruses: Who gets the short end of the stick?

NK cells are innate lymphocytes that play a key role in the control of various viral infections. Recent studies indicate that NK cells may acquire some features of adaptive immune cells, including the formation of long‐lived memory cells. A large and growing body of data indicates that NK cells regulate the adaptive immune response as well. The function and the activation status of NK cells are tightly regulated by signals induced by a broad range of inhibitory and activating cell surface receptors and cytokines released by other immune cells. Here, we review the function of mouse NK‐cell receptors involved in virus control and in the regulation of the adaptive immune response. In addition, we discuss viral strategies used to evade NK‐cell‐mediated control during infection. Finally, the role of several activating Ly49 receptors specific for mouse cytomegalovirus (MCMV), as well as some controversial issues in the field, will be discussed.     

HIV‐1 and hijacking of the host immune system: the current scenario

Human immunodeficiency virus (HIV) infection is a major health burden across the world which leads to the development of acquired immune deficiency syndrome (AIDS). This review article discusses the prevalence of HIV, its major routes of transmission, natural immunity, and evasion from the host immune system. HIV is mostly prevalent in Sub‐Saharan Africa and low income countries. It is mostly transmitted by sharing syringe needles, blood transfusion, and sexual routes. The host immune system is categorized into three main types; the innate, the adaptive, and the intrinsic immune system. Regarding the innate immune system against HIV, the key players are mucosal membrane, dendritic cells (DCs), complement system, interferon, and host Micro RNAs. The major components of the adaptive immune system exploited by HIV are T cells mainly CD4+ T cells and B cells. The intrinsic immune system confronted by HIV involves (apolipoprotein B mRNA‐editing enzyme, catalytic polypeptide‐like 3G) APOBEC3G, tripartite motif 5‐α (TRIM5a), terherin, and (SAM‐domain HD‐domain containing protein) SAMHD1. HIV‐1 efficiently interacts with the host immune system, exploits the host machinery, successfully replicates and transmits from one cell to another. Further research is required to explore evasion strategies of HIV to develop novel therapeutic approaches against HIV.     

Levamisole enhances immune response by affecting the activation and maturation of human monocyte-derived dendritic cells

The primary aim of this study was to evaluate the role of natural killer (NK) cells on antigen-specific adaptive immune responses. After analysing the mechanism of impaired adaptive immune responses of NK-depleted mice, an immune interventional approach was developed to restore adaptive immunity in NK-depleted mice. NK cells were depleted from mice by administration of anti-asialo GM1 antibody (100 mul/mouse), twice, at an interval of 48 h. Hepatitis B surface antigen (HBsAg) was administered intraperitoneally to normal C57BL/6 mice (control mice) and NK-depleted mice. The levels of antibody to HBsAg (anti-HBs) in the sera and HBsAg-specific lymphocytes in the spleen were assessed. The functions of T lymphocytes, B lymphocytes and dendritic cells (DCs) were evaluated in vitro. HBsAg-pulsed DCs were prepared by culturing spleen DCs with HBsAg for 48 h and administered once to NK-depleted mice. The levels of anti-HBs in the sera and HBsAg-specific lymphocytes were significantly lower in NK-depleted mice compared with control mice (P < 0.05). The functions of T and B lymphocytes were similar between control mice and NK-depleted mice. However, the functions of spleen DC and liver DC were significantly lower in NK-depleted mice compared with control mice (P < 0.05). Administration of HBsAg-pulsed DCs, but not HBsAg, induced HBsAg-specific humoral and cellular immune responses in NK-depleted mice. Our study suggests that cross-talk between NK cells and DCs regulates the magnitude of adaptive immunity. In addition, antigen-pulsed immunogenic DCs represent potent immune modulator even if subjects with diminished innate immunity.     

Cutaneous Perspectives on Adaptive Immunity

The skin, situated at the critical juncture between the host and the environment, is subject to a variety of potentially damaging agents including microbial organisms, toxins, and gene-altering radiation. Diverse immunocytes, including those resident in the skin and those with the capacity to traffic to and from the skin, direct two major types of immune responses: more immediate and less discriminate defenses (so-called innate immunity), and more coordinated and antigen-specific responses (so-called adaptive immunity). This review will focus on features of the adaptive immune system operative within the skin and consider the roles of dendritic cells, lymphocytes, endothelial cells, chemokines, and cytokines. In particular, the major subsets of T cells and the mechanisms by which they endow and regulate the features of adaptive immunity in the skin will be considered, including: the efficient surveillance and recognition of diverse foreign-antigens while limiting reactivity against self-antigens; differentiation into various effector cells capable of inducing apoptosis of infected/damaged cells and/or directing the activities of other immunocytes; and providing for immunologic memory whereby subsequent antigen exposure elicits a rapid and augmented antigen-specific response. It is within this context that the adaptive immune system will be considered for its role in the skin in mediating microbial defense with direct relevance to tumor immunosurveillance and inflammatory disease.     

Innate lymphoid cells: The missing part of a puzzle in food allergy

Food allergy is an increasingly prevalent disease driven by uncontrolled type 2 immune response. Currently, knowledge about the underlying mechanisms that initiate and promote the immune response to dietary allergens is limited. Patients with food allergy are commonly sensitized through the skin in their early life, later on developing allergy symptoms within the gastrointestinal tract. Food allergy results from a dysregulated type 2 response to food allergens, characterized by enhanced levels of IgE, IL-4, IL-5, and IL-13 with infiltration of mast cells, eosinophils, and basophils. Recent studies raised a possible role for the involvement of innate lymphoid cells (ILCs) in driving food allergy. Unlike lymphocytes, ILCs lack They represent a group of lymphocytes that lack specific antigen receptors. ILCs contribute to immune responses not only by releasing cytokines and other mediators but also by responding to cytokines produced by activated cells in their local microenvironment. Due to their localization at barrier surfaces of the airways, gut, and skin, ILCs form a link between the innate and adaptive immunity. This review summarizes recent evidence on how skin and gastrointestinal mucosal immune system contribute to both homeostasis and the development of food allergy, as well as the involvement of ILCs toward inflammatory processes and regulatory mechanisms.     

The impact of eicosanoids on the crosstalk between innate and adaptive immunity: the key roles of dendritic cells

The innate immune response is essentially the first line of defense against an invading pathogen. Through specialized receptors, known as pattern recognition receptors, especially Toll-like receptors, specialized cells of myeloid origin, including macrophages and dendritic cells (DCs) are able to phagocytose microorganisms and induce an innate inflammatory response. Although B and T lymphocytes recognize tissue antigens with high specificity, they are unable to initiate immune responses. The decision to activate an appropriate immune response is made by unique DC, the most professional antigen-presenting cells (APCs) which control the responses of several types of lymphocytes and play central role in the transition between innate and adaptive immunity. Increased secretion of inflammatory endogenous mediators such as cytokines and arachidonic acid-derived lipid mediators, also termed eicosanoids, can activate APC, particularly DC, which in turn induce an adaptive immune response. There is an increasing evidence that eicosanoids play an important role in connecting innate and adaptive immunity by acting on cells of both systems. Prostanoids, a major class of eicosanoids, have a great impact on inflammatory and immune responses. PGE(2) is one of the best known and most well-characterized prostanoids in terms of immunomodulation. Although cytokines are known as key regulators of immunity, eicosanoids, including PGE(2), PGD(2), LTB(4), and LTC(4), may also affect cells of immune system by modulating cytokine release, cell differentiation, survival, migration, antigen presentation, and apoptosis. By acting on various aspects of immune and inflammatory reactions, these lipid mediators emerge as key regulators of the crosstalk between innate and adaptive immunity.