调节性T细胞在支气管哮喘中的重要作用

本文论述了调市性T细胞的概念及几种主要的调节性T细胞：Th1、Th2、Th3细胞、TR细胞、CD4^ CD25^ 细胞、NKT细胞的主要特点和研究现状。并论述了这儿种调节性T细胞在支气管哮喘中的重要作用。提出Th1细胞更趋向于一种炎症细胞而非抗炎细胞,而其他各种调节性T细胞可能提供免疫保护及抗炎作用起到抑制哮喘发展的作用,通过控制调节性T细胞的治疗可能成为哮喘治疗的有效手段。     

Th17细胞和调节性T细胞在炎症性疾病中的研究进展

Th17细胞和调节性T细胞(Treg)是具有相反作用的T细胞亚群,它们的平衡有利于维持机体稳定的免疫状态,在炎症性疾病中发挥重要作用。在炎性条件下,Treg可以转换成Th17细胞,Th17细胞数量增多,Treg数量显著减少或其抑制功能降低,致使Th17细胞/Treg的失衡,从而导致炎症性疾病的发生和发展。Th17细胞/Treg的平衡紊乱已经成为炎症性疾病研究领域中的新热点。本文对Th17细胞和Treg的基本功能作用、两者之间的平衡关系及其机制以及Th17细胞/Treg与炎症性疾病的关系进行了综述,为炎症性疾病的早期诊断、预后及免疫治疗提供新的思路。     

γδT细胞在小鼠自身免疫性葡萄膜炎中保护作用的实验研究

目的:γδT细胞在自身免疫性葡萄膜炎(EAU)中的作用尚不完全清楚。以往认为γδT细胞可能是诱导免疫炎症反应的重要启动因素,但体内研究结果:不一。本文拟探讨γδT细胞在EAU的发病中的致病或保护作用。方法:分离纯化小鼠γδT细胞,体外抗原激活后输注于野生型B6小鼠;用GL3抗体注射法清除野生型B6小鼠体内的γδT细胞;或直接使用γδT细胞基因敲除小鼠,IRBP1-20免疫法制作小鼠EAU模型,观察小鼠眼球炎症的临床评分和病理改变,与野生型B6小鼠的EAU模型相比较。结果:1)EAU时γδT细胞数量明显增加;2)早期活化的γδT细胞主要产生和表达IL-17;3)预先输注活化的γδT细胞后,IRBP1-20诱导的EAU眼球炎症明显减轻;4)GL3清除γδT细胞后,EAU眼球炎症明显加重,γδT细胞基因敲除小鼠的EAU眼球炎症明显加重;5)缺乏γδT细胞的小鼠预先输注γδT细胞后,EAU炎症明显减轻。结论:激活的γδT细胞在EAU发病中可能起到控制免疫炎症不致失控的保护作用,这种保护作用可能是通过产生IL-17实现的。     

Th17细胞与Treg细胞比例失衡在慢性炎症性疾病中研究进展

慢性炎症性疾病涉及许多疾病的发展过程,如变应性鼻炎、支气管哮喘、类风湿性关节炎（rheumatoid arthritis,R A）、炎症性肠病（inflammator y bowel disease,IBD）等。研究发现,Th17和Treg细胞通过其自身及产生的相应细胞因子,在慢性炎症性疾病发生发展过程中起着重要作用,而Th17和调节性T细胞（T Regulator Cell,Treg细胞）的分化共用了TGF-β这个细胞因子,提示他们在分化过程中有某种关联。本文旨在阐述Th17细胞与Treg细胞比例失衡在相关慢性炎症性疾病的发生发展中所起的关键作用。     

良性前列腺增生中T细胞的作用

良性前列腺增生是一种老年人的常见疾病，极大影响老年人生活质量，给患者和社会带来巨大负担。由于其确切发病机制及病因仍不明确，限制了良性前列腺增生治疗方式的改进。目前越来越多的研究表明前列腺慢性炎症在良性前列腺增生的发生、发展中发挥重要作用，并可能促进前列腺癌变。T细胞作为良性前列腺增生慢性炎症细胞的主要成分，其作用不可小觑。因此，本文归纳了近年来T细胞在良性前列腺增生的研究进展，总结了T细胞在良性前列腺增生发生、发展中的作用，以及T细胞在良性前列腺增生与前列腺癌关系中可能发挥的作用，期望进一步推动良性前列腺增生的研究进展。     

间充质干细胞在T细胞免疫反应中的调节作用

间充质干细胞(MSCs)独特的免疫调节作用以T细胞为主,在混合淋巴细胞反应中,通过周期阻滞抑制T细胞增殖,但不引起T细胞凋亡增加、活化受抑。同时MSCs还能降低反应体系中的CD8+T细胞和Th1细胞,升高Th2细胞以抑制炎症反应,从而在T细胞介导的自身免疫性疾病中发挥治疗作用。     

辅助性T细胞9及其功能研究进展

CD4+T细胞在免疫应答反应中发挥关键作用,CD4+T细胞根据其分泌的细胞因子的不同分为多种细胞亚群.其中辅助性T细胞9(Th9)细胞是最近发现的一种新型的CD4+效应T细胞,该细胞由Na(i)ve CD4+T细胞分化而来,可分泌特征性的细胞因子白细胞介素(IL)-9.Th9细胞的发育和分化具有独立的调节机制,其在过敏性炎症、自身免疫病和抗肿瘤免疫中发挥着重要作用.然而,Th9细胞在免疫应答反应中的调控,与其它CD4+T细胞亚群的相互作用及在疾病中的效应作用等问题仍需深入研究.     

Tfh与Tfr的研究进展及其在类风湿性关节炎发展中的作用

滤泡辅助性T细胞(follicular helper T cell,Tfh)和滤泡调节性T细胞(follicular regulatory T cell,Tfr)是近年新发现的两种重要的T细胞类型,它们对促进生发中心(germinal center,GC)形成、B细胞发育及高亲和抗体产生具有重要作用。类风湿性关节炎(rheumatoid arthritis,RA)是一种常见的慢性系统性自身免疫性疾病,以关节滑囊组织炎症和关节退化为主要特征,同时存在多种自身反应性抗体的异常表达。本文综述Tfh与Tfr的分化与分子标志及主要功能的研究进展,阐述两种细胞在RA发展中的可能作用。     

大肠癌肿瘤微环境中Th17细胞与调节性T细胞的作用及临床意义

大肠癌是全球最常见的恶性肿瘤之一,大肠癌的发生、发展与肠内慢性炎症(CRC)密切相关,而部分炎症细胞及其分泌的细胞因子在这一过程中扮演着重要角色,肿瘤浸润效应T细胞与多种类型肿瘤病人的预后密切相关,辅助性T细胞17(Th17)是新近发现的一类CD4+效应T细胞亚群,在炎症、自身免疫性疾病和肿瘤中发挥积极作用.调节性T细胞(Tregs)在功能上是T细胞的免疫抑制亚群,在自身免疫耐受和抗肿瘤免疫中起重要作用.Th17细胞和Treg细胞之间的动态平衡在保持免疫调控功能中至关重要.     

不同类型的调节性T细胞在类风湿关节炎中的作用

类风湿关节炎是一种系统性自身免疫性疾病,以慢性关节炎症、骨和软骨侵蚀以及滑膜组织增生为特征,目前关于RA的发病机制尚未明确。效应性T细胞即辅助性T细胞及其分泌的细胞因子的水平失衡是RA发病的重要机制,其中调节性T细胞作为一类免疫抑制性T细胞,在介导免疫稳态、维持免疫耐受及控制疾病进展方面起重要作用,因此深入研究不同亚型的Treg在RA中的功能和作用可能为RA的治疗提供新思路。     

A critical analysis of the T cell hybrid technique

The T cell hybridization technique can be used to prepare continuous cell lines which express the antigen specificity and function of T cells within the milieu of a proliferating lymphoma. Technical details for the preparation and maintenance, selection and analysis of T cell hybrids are defined. Techniques for cloning of hybrid cells and production of hybrid-derived tumors are also presented. Parameters influencing the hybridization frequency and the production of functional hybrids are discussed. A variety of T cell subsets, including suppressor cells and delayed-type hypersensitivity effector cells as well as T cells maintained on TCGF, are excellent sources of primary parents for hybridization. When BW 5147 is used as the T lymphomas parent in these experiments, the resulting hybridization frequencies range between 10 and 434 X 10(-7). We have had moderate success using YAC-1; however, additional lines such as L5178Y, BALENTL 5, EL4 BU and S491TB.2 have proved ineffective as sources of T lymphoma parents. The technique of T cell hybridization is evaluation in terms of retention of differentiated functions and the stability and growth characteristics of the resultant hybrids.     

Thymocytes self-renewal: a major hope or a major threat?

Thymus transplants were never used to correct T-cell intrinsic deficiencies, as it is generally believed that thymocytes have short intrinsic lifespans. This notion is based on multiple thymus transplantation experiments, where it was shown that thymus-resident cells were rapidly replaced by progenitors migrating from the bone marrow (BM). This substitution occurs even when bone marrow precursors are unable to generate T cells, as in Rag1/2⁻ or severe combined immunodeficiency (SCID)-deficient mice. In contrast, two groups reported that neonatal thymi transplanted into mice that cannot respond to IL-7 harbor populations with extensive capacity to self-renew, which maintain continuous thymocyte generation for several months after surgery. The consequences of this self-renewal capacity differed in these two laboratories. We found that these thymus transplants rapidly reconstitute the full diversity of peripheral T-cell repertoires 1 month after surgery, the earliest time point studied. Moreover, transplantation experiments performed across major histocompatibility barriers show that allogeneic-transplanted thymi are not rejected, and allogeneic cells do not induce graft-versus-host disease, both syngeneic and allogeneic transplants inducing rapid protection from infection. These results indicate a potential use of neonatal thymus transplants to correct T-cell intrinsic deficiencies. The other group observed that continuous thymocyte renewal from BM precursors was fundamental to prevent tumor development. In the absence of this input, thymocytes from the transplanted thymus generated tumors with all the characteristics of T-cell acute lymphoblastic leukemia (T-ALL). Moreover, they suggested that the absence of BM competition was responsible for the T-ALLs developing in X-linked severe combined immunodeficiency (SCID)-X1 patients, deficient in the expression of IL2-Rγ_c. These patients were treated with autologous CD34⁺ cells transfected with virus vectors expressing γ_c in the absence of myeloablation. We here review the potential therapeutic impact of thymus transplantation and compare the results of these two laboratories aiming to find an answer to the ‘Dr Jekill versus Mr. Hyde’ status of thymus transplantation experiments.     

卵清白蛋白特异性T细胞免疫诱导BALB/c小鼠的调节性免疫应答

目的：研究T细胞免疫后正常小鼠的调节性免疫应答，方法：应用体外扩增的卵清白蛋白（OVA）特异的T细胞克隆免疫BALB／c小鼠，3H－TdR掺入法分析细胞增殖，3H－TdR标记靶细胞检测杀伤T细胞的杀伤效应，间接免疫荧光法分析血清中抗T细胞抗体水平。结果：T细胞免疫后能诱导BALB/c小鼠产生调节性T细胞的增殖反应，对靶细胞的杀伤效应以及针对于活化的T细胞的体液免疫应答，并进一步降低机体对OVA抗原的应答，结论：T细胞免疫能诱导正常机体的调节性免疫应答。     

Thymic Hormone-Induced Accelerated Development of Antibody Responsiveness to Sheep Red Blood Cells in the Newborn Mouse*

ABSTRACT: The influence of thymic preparations on the kinetics of the development of PFC response to sheep erythrocytes was tested in mice 0 to 4 weeks old. Soluble thymic factor (STF) or thymic epithelial culture supernatant (TES) was prepared from the thymuses of C57B1/6 mice. STF was injected to gravid mice on day 13 or on day 18 of gestation. A marked acceleration in the appearance of PFC to SRBC was noted only in the offspring from those mothers having received STF on day 18. The ability to generate anti-SRBC response in vitro by splenocytes from 1-to 4-week-old mice was significantly improved in the presence of TES. The accelerated appearance of the response to a T-dependent antigen is attributed to increase in the ratio of T helper/T suppressor cells resulting from differentiation and/or clonal expansion under the influence of STF crossing of the placental barrier in the materno-fetal direction.     

Special regulatory T-cell review: A rose by any other name: from suppressor T cells to Tregs, approbation to unbridled enthusiasm

In the early 1970s a spate of papers by research groups around the world provided evidence for a negative regulatory role of thymus-derived lymphocytes (T cells). In 1971, Gershon and Kondo published a seminal paper in Immunology entitled 'Infectious Immunological Tolerance' indicating that such negative regulation could be a dominant effect that prevented otherwise 'helpful' T cells from mediating their function. Over the next decade, suppressor T cells, as these negative regulatory cells became known, were intensively investigated and a complex set of interacting cells and soluble factors were described as mediators in this process of immune regulation. In the early 1980s, however, biochemical and molecular experiments raised questions about the interpretation of the earlier studies, and within a few years, the term 'suppressor T cell' had all but disappeared from prominence and research on this phenomenon was held in poor esteem. While this was happening, new studies appeared suggesting that a subset of T cells played a critical role in preventing autoimmunity. These T cells, eventually dubbed 'regulatory T cells', have become a major focus of modern cellular immunological investigation, with a predominance that perhaps eclipses even that seen in the earlier period of suppressor T cell ascendancy. This brief review summarizes the rise and fall of 'suppressorology' and the possibility that Tregs are a modern rediscovery of suppressor T cells made convincing by more robust models for their study and better reagents for their identification and analysis.     

CD52 is a novel costimulatory molecule for induction of CD4+ regulatory T cells

We previously reported that 4C8 monoclonal antibody (mAb) provides a costimulatory signal to human CD4+ T cells and consequently induces regulatory T (Treg) cells, which are hypo-responsive and suppress the polyclonal response of bystander CD4+ cells in a contact-dependent manner. In this study, we identified the antigen of 4C8 mAb as CD52. Costimulation with Campath-1H, a humanized anti-CD52 mAb, also induced Treg cells. Anti-CD52-induced Treg cells suppressed the proliferation of both CD4+ and CD8+ T cells provided with polyclonal or allogeneic stimulation. When Treg cells were induced from Staphylococcal enterotoxin B (SEB) treated cells, they suppressed the response to SEB more efficiently than that to another superantigen, SEA. Furthermore, anti-CD52-induced Treg cells could be expanded by culture with IL-2 followed by CD52-costimulation, and co-injection of expanded Treg cells suppressed lethal xenogeneic graft versus host disease (GvHD) reactions in SCID mice caused by human peripheral blood mononuclear cells (PBMCs).     

Clonal growth of carp (Cyprinus carpio) T cells in vitro

Carp kidney leukocytes co-cultured with a supporting cell layer resulted in the rapid proliferation of various types of leukocytes including immature leukocytes. Expressions of marker genes for multiple blood cell lineages were observed in the primary culture. However, after several passages, the proliferating cells expressed only T cell and macrophage marker genes.Further RT-PCR analysis revealed that the proliferating cells expressed TCR constant regions (Cα, Cβ, Cγ, Cδ), CD3γ/δ and CD4 (CD4L-1), but did not express CD8α and CD8β. Additionally, in situ hybridization analysis showed that the majority of proliferating cells expressed Cα, Cβ, Cγ, Cδ and CD4. Moreover, 5′-RACE sequences of TCR variable regions (Vα, Vβ, Vγ, Vδ) revealed that the proliferating cells contained a polyclonal T cell repertoire, and most of the Vα and Vβ sequences were functional, but the Vγ and Vδ sequences were non-functional with frame shifts and stop codons. Taken together, these results indicate that the proliferating cells after serial passages predominantly contained CD4+ CD8− αβT cells that simultaneously co-expressed non-functional γδTCR. To obtain CD4+ αβT cell (helper T cell) clones, single cells were picked up from the bulk culture, seeded into each well of 96-well plates and cultured in the presence of supporting cells and conditioned media. T cell colonies formed from single cells after 2-3 weeks. These colony cells expressed Cα, Cβ, Cδ and CD4, and weakly expressed Cγ, but did not express CD8α, CD8β and CD4L-2. Taken together, these results indicate that these clonal T cells resemble a subpopulation of mammalian CD4+ helper T cells.     

Effector memory T cell subset CD45RA−CCR7−CD27−CD28− EM3 increases in direct proportion to the disease severity of COVID-19

COVID-19, which emerged in December 2019 and continues to wreak havoc, has led to the death of many people around the world. In this study, we aimed to uncover the variables underlying the exacerbation of the disease by considering the changes in T cell subsets in adults and juveniles with different disease severity of COVID-19. Peripheral blood samples of 193 patients (128 adults and 65 juveniles) diagnosed with COVID-19 were evaluated in a flow cytometer, and a broad T cell profile was revealed by examining T cell subsets in terms of exhaustion and senescence. We found remarkable differences in the effector memory (EM; CD45RA⁻CCR7⁻) cell subsets of severe pneumonia cases. The frequencies of EM₂ CD4⁺ T, EM₃ CD4⁺ T, EM₃ CD8⁺ T, EM₂ DN T and EM₃ DN T cells were found to increase in severe pneumonia cases. Consistently, these cells were found in juveniles and uncomplicated adults in similar or lower proportions to healthy controls. The findings of our study provide a view of the T cell profile that may underlie differences in the course of COVID-19 cases in juveniles and adults and may provide new insights into the development of effective treatment strategies.