调节性B细胞及其在类风湿关节炎中的研究进展

调节性B细胞(regulatory B cells, Bregs)是一类具有免疫抑制功能的B细胞亚群,可通过表达分化抗原1d(cluster of differentiation 1d, CD1d)、凋亡相关因子配体(factor related apoptosis ligand, FasL)、程序性死亡配体-1(programmed death ligand-1, PD-L1)等膜结合因子,分泌白细胞介素-10(interleukin-10, IL-10)、IL-35、转化生长因子-β(transforming growth factor-β, TGF-β)、颗粒酶B和腺苷等多种机制发挥其免疫抑制功能。近年研究发现,Bregs在类风湿关节炎(rheumatoid arthritis, RA)发病机制中起到重要作用,且有可能成为治疗RA等自身免疫性疾病的新靶点。现就Bregs及其在RA中的研究进展作一概述。     

调节性B细胞的发现和研究进展

B细胞主要通过呈递抗原和产生抗体发挥免疫调节作用.新近研究表明,一种全新的B细胞亚群--调节性B细胞(regulatory B cell,Bregs),可通过产生白细胞介素10(IL-10)或转化生长因子β1(TGF-β1)等抑制性细胞因子介导免疫耐受,抑制过度炎症反应.Bregs在一些慢性炎性疾病包括肠炎、类风湿性关节炎、实验性自身免疫脑脊髓炎、多发性硬化症、感染和肿瘤等发生、发展和转归过程起重要调节作用.Bregs的发现和作用机制的阐明,将为全面、深入了解免疫耐受的机制,寻找和开发更合理治疗慢性炎性疾病的策略提供理论依据.本文综述了Bregs的发现、生物学特征、发育调节及其参与炎性疾病发病的作用和机制.     

CD4+T细胞在肿瘤免疫治疗中的作用

近年来,人们对CD4 T细胞在肿瘤免疫治疗中的作用给予了极大的关注,CD4 T细胞不仅可通过IFN-γ依赖性等机制直接杀伤肿瘤细胞,而且在CD8 T细胞的激活、记忆性的细胞毒性T细胞(CTL)应答的产生、维持以及促进其存活等过程中发挥着重要作用,同时激活CD4 T细胞和CD8 T细胞是免疫治疗的理想策略;另外,CD4 CD25 调节性T细胞(Treg细胞)可能被肿瘤表达的自身抗原所诱导,与肿瘤免疫耐受的维持和抗肿瘤应答的下调有关,被认为是免疫治疗失败的主要原因,抑制该细胞亚群可增强治疗性肿瘤疫苗的临床效果.现就CD4 T细胞在肿瘤免疫治疗中的作用的研究进展作一综述.     

调节性T细胞在动脉粥样硬化发病中的作用

CD4^＋CD25^＋调节性T细胞（CD4^＋CD25^＋Treg）是一个具有独特免疫调节功能的T细胞亚群,它不仅抑制自身免疫性疾病的发生,而且可能参与诱导移植耐受以及肿瘤免疫调节,在维持机体内环境稳态中起重要作用。本文综述了CD4^＋CD25^＋调节性T细胞的特点和调节机制,以及在动脉粥样硬化发生发展中的可能作用。最新研究提示其可能是机体内源性有效的抑制动脉粥样硬化的因子。这些研究成果为理解动脉粥样硬化的免疫病理机制提供了新的观点,并可能为应用调节性T细胞作为靶点,寻找治疗动脉粥样硬化的免疫调节制剂提供新的策略。     

CD4+CD25+调节性T细胞与肿瘤免疫

调节性T细胞是一类具有免疫抑制作用,调节自身T细胞功能的T细胞亚群,与维持免疫耐受、抑制自身免疫性疾病有关,CD4＋CD25＋调节性T细胞是其重要组成部分.该文介绍CD4＋CD25＋调节性T细胞在癌症患者免疫系统中的失调现象、机制和以其为靶点的免疫治疗方式.     

夏氏疟原虫感染过程中调节性B细胞的表达变化

调节性B细胞(regulatory B cells,Bregs)是近年来发现的通过分泌IL-10发挥免疫调节作用的B细胞,其在疟疾免疫应答中的作用尚不清楚。利用血液阶段夏氏疟原虫(Plasmodium chabaudi AS,P.c AS)感染的BALB/c小鼠,观察了感染过程中Bregs数量变化及其表面分子表达情况。结果显示,BALB/c小鼠感染P.c AS后红细胞感染率逐渐升高,于感染后第9天达到30%,多数小鼠死亡。脾组织细胞因子IL-10 mRNA水平在感染后显著升高,感染后第5天达到高峰,感染后第8天仍为正常小鼠的10倍左右。CD4+细胞中IL-10+细胞百分比和绝对数量在感染后第5天达到峰值,于感染后第8天回落至正常水平;而CD19+细胞中IL-10+细胞(Bregs)百分比在感染后持续上升,在感染后第8天达到CD19+细胞的5%左右;感染后第5天,脾中CD4+IL-10+细胞绝对数量高于CD19+IL-10+细胞,至感染后第8天,CD19+IL-10+细胞绝对数量显著高于CD4+IL-10+细胞(P﹤0.01),约90%Bregs为CD5-细胞。结果提示,P.c AS感染过程中Bregs显著活化,是感染1周后IL-10的主要产生细胞。     

调节性T细胞与胶质瘤的免疫治疗

调节性T细胞（regulatory T cell,Treg）是一群具有抑制其它免疫细胞功能的起负性调控的细胞群. Treg细胞能抑制多种免疫细胞,如CD4+T和CD8+T淋巴细胞、NK细胞、B淋巴细胞以及树突状细胞的活化和增殖,是体内维持免疫系统稳定,防止出现自身免疫性疾病重要因素.最新研究表明,Treg细胞在肿瘤免疫逃逸中也发挥重要作用. 肿瘤细胞通过扩增或招募Treg细胞,抑制机体对肿瘤的免疫作用,由此可知,Treg细胞在肿瘤的发生和发展过程中发挥重要作用. 因此,抑制Treg细胞的活性和数量是包括胶质瘤在内的肿瘤免疫治疗有效的方式.     

γδT细胞在肿瘤免疫治疗中的研究进展

癌症是威胁人类健康最主要的疾病之一,目前临床上主要采用的手术/放化疗联合治疗的疗效有限,因此如何进一步提高肿瘤临床疗效仍是巨大的挑战。免疫细胞过继是肿瘤治疗技术中迅速发展的一种生物治疗技术,通过输入自身或同种\"抗肿瘤免疫效应细胞\"达到直接杀伤肿瘤或增强机体自身细胞免疫功能的作用。由于γδT细胞对肿瘤细胞具有强有力的直接细胞毒性,并可与其他免疫细胞协同作用发挥其抗肿瘤活性,因而成为了细胞免疫治疗中新的研究热点。本文主要叙述了γδT细胞与肿瘤相关的基础研究及临床试验的最新进展。     

树突状细胞在肿瘤免疫治疗中的应用研究进展

树突状细胞（DC）是人体内最强的抗原提呈细胞。未成熟的DC可摄取抗原并迁移至淋巴器官,将抗原信息传递给免疫系统,引发免疫应答。研究表明,DC在启动抗肿瘤免疫中发挥着强大的功能。近年来,以DC为基础的肿瘤疫苗已成为肿瘤免疫治疗的热点。简要综述了各种DC疫苗的制备和临床应用。     

调节性T细胞在肿瘤免疫和肿瘤免疫治疗中的作用

肿瘤是当前世界上常见的慢性渐进性疾病,生长速度快,转移性高,治愈性低且易复发,给临床治疗造成了极大的困难。当前的治疗手段有手术切术、化疗等方法,但是仍然没有从根本上提高肿瘤的治愈率。肿瘤局部存在着多种类型的免疫抑制性细胞,其中T细胞通过多种机制抑制免疫细胞的功能,使肿瘤免疫得以逃避。包括分泌颗粒酶和穿孔酶杀伤效应细胞、扰乱效应细胞的功能、分泌抑制性细胞因子等手段。对于肿瘤治疗的突破需要我们通过多种途径进行,而调节T细胞成为肿瘤治疗的又一突破口。     

The role of c-FLIP splice variants in urothelial tumours

Deregulation of apoptosis is common in cancer and is often caused by overexpression of anti-apoptotic proteins in tumour cells. One important regulator of apoptosis is the cellular FLICE-inhibitory protein (c-FLIP), which is overexpressed, for example, in melanoma and Hodgkin''s lymphoma cells. Here, we addressed the question whether deregulated c-FLIP expression in urothelial carcinoma impinges on the ability of death ligands to induce apoptosis. In particular, we investigated the role of the c-FLIP splice variants c-FLIP_long (c-FLIP_L) and c-FLIP_short (c-FLIP_S), which can have opposing functions. We observed diminished expression of the c-FLIP_L isoform in urothelial carcinoma tissues as well as in established carcinoma cell lines compared with normal urothelial tissues and cells, whereas c-FLIP_S was unchanged. Overexpression and RNA interference studies in urothelial cell lines nevertheless demonstrated that c-FLIP remained a crucial factor conferring resistance towards induction of apoptosis by death ligands CD95L and TRAIL. Isoform-specific RNA interference showed c-FLIP_L to be of particular importance. Thus, urothelial carcinoma cells appear to fine-tune c-FLIP expression to a level sufficient for protection against activation of apoptosis by the extrinsic pathway. Therefore, targeting c-FLIP, and especially the c-FLIP_L isoform, may facilitate apoptosis-based therapies of bladder cancer in otherwise resistant tumours.     

Emerging role of metabolic reprogramming in tumor immune evasion and immunotherapy

Mounting evidence has revealed that the therapeutic efficacy of immunotherapies is restricted to a small portion of cancer patients. A deeper understanding of how metabolic reprogramming in the tumor microenvironment(TME) regulates immunity remains a major challenge to tumor eradication. It has been suggested that metabolic reprogramming in the TME may affect metabolism in immune cells and subsequently suppress immune function. Tumor cells compete with infiltrating immune cells for nutrients and metabolites. Notably, the immunosuppressive TME is characterized by catabolic and anabolic processes that are critical for immune cell function, and elevated inhibitory signals may favor cancer immune evasion. The major energy sources that supply different immune cell subtypes also undergo reprogramming. We herein summarize the metabolic remodeling in tumor cells and different immune cell subtypes and the latest advances underlying the use of metabolic checkpoints in antitumor immunotherapies. In this context, targeting both tumor and immune cell metabolic reprogramming may enhance therapeutic efficacy.     

The enigmatic role of angiopoietin-1 in tumor angiogenesis

A tumor vasculature is highly unstable and immature, characterized by a high proliferation rate of endothelial cells, hyper-permeability, and chaotic blood flow. The dysfunctional vasculature gives rise to continual plasma leakage and hypoxia in the tumor, resulting in constant on-sets of inflammation and angiogenesis. Tumors are thus likened to wounds that will not heal. The lack of functional mural cells, including pericytes and vascular smooth muscle cells, in tumor vascular structure contributes significantly to the abnormality of tumor vessels. Angiopoietin-1 (Ang 1) is aphysiological angiogenesis promoter during embryonic development. The function of Angl is essential to endothelial cell survival, vascular branching, and pericyte recruitment. However, an increasing amount of experimental data suggest that Angl-stimulated association of mural cells with endothelial cells lead to stabilization of newly formed blood vessels. This in turn may limit the otherwise continuous angiogenesis in the tumor, and consequently give riseto inhibition of tumor growth. We discuss the enigmatic role of Angl in tumor angiogenesis in this review.     

The role of the microenvironment in tumor growth and invasion

Mathematical modeling and computational analysis are essential for understanding the dynamics of the complex gene networks that control normal development and homeostasis, and can help to understand how circumvention of that control leads to abnormal outcomes such as cancer. Our objectives here are to discuss the different mechanisms by which the local biochemical and mechanical microenvironment, which is comprised of various signaling molecules, cell types and the extracellular matrix (ECM), affects the progression of potentially-cancerous cells, and to present new results on two aspects of these effects. We first deal with the major processes involved in the progression from a normal cell to a cancerous cell at a level accessible to a general scientific readership, and we then outline a number of mathematical and computational issues that arise in cancer modeling. In Section 2 we present results from a model that deals with the effects of the mechanical properties of the environment on tumor growth, and in Section 3 we report results from a model of the signaling pathways and the tumor microenvironment (TME), and how their interactions affect the development of breast cancer. The results emphasize anew the complexities of the interactions within the TME and their effect on tumor growth, and show that tumor progression is not solely determined by the presence of a clone of mutated immortal cells, but rather that it can be ‘community-controlled’.     

肿瘤特异性抗原(MAGE)在肿瘤免疫治疗中的作用

目前,已经发现肿瘤特异性抗原Mage基因家族有55个成员,其中MageA、B和C三个亚家族在各种组织来源的恶性肿瘤中特异性表达,正常组织(睾丸除外)均不表达。所以,Mage抗原作为肿瘤的特异性标志,在肿瘤的检测和免疫治疗方面具有很大的应用潜力。本文介绍了Mage家族的基因定位,Mage蛋白的特性,Mage基因的作用。同时,总结了近年来Mage基因家族在临床方面的应用研究结果。     

Smectite promotes probiotic biofilm formation in the gut for cancer immunotherapy

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COX-2及其抑制剂在肿瘤防治中的作用

环氧化酶（cyclooxygenase,COX）是前列腺素合成途径中主要的限速酶之一,参与炎症、发热、出凝血等病理生理过程。COX-2在肿瘤发生发展、转移、凋亡抑制及促进肿瘤血管生成等方面发挥重要作用,己成为肿瘤防治的一个新靶点;COX-2及其抑制剂在肿瘤预防、放疗、化疗、生物疗法中具有广阔应用前景。本文就COX-2及其抑制剂在肿瘤防治中的进展作一详细综述。     

An essential role for Akt1 in dendritic cell function and tumor immunotherapy

Current dendritic cell (DC) vaccine preparations involving ex vivo differentiation and maturation produce short-lived, transiently active DCs that may curtail T-cell responses in vivo. We demonstrate that Akt1, downregulation of which decreases DC lifespan, is critical for proinflammatory signal-mediated DC survival and maturation. Lipopolysaccharide or CD40 signaling stabilizes Akt1, promoting both activation and Bcl-2-dependent survival of DCs. Expression of a potent allele encoding a lipid raft-targeted Akt1, M(F)-DeltaAkt, is sufficient for maturation and survival of murine bone marrow-derived DCs in vivo. M(F)-DeltaAkt-transduced DCs enhanced T-cell proliferation, activation and long-term memory responses, enabling eradication of large pre-established lymphomas and aggressive B16 melanomas. Human myeloid DCs expressing constitutively active M(F)-DeltahAkt also survived significantly longer and promoted antigen-specific T-cell responses. Thus, Akt1 is a critical regulator of DC lifespan, and its manipulation in DCs can improve the clinical efficacy of DC-based tumor vaccines.     

The role of ephrins and Eph receptors in cancer

Eph receptors are the largest receptor tyrosine kinase family of transmembrane proteins with an extracellular domain capable of recognizing signals from the cells’ environment and influencing cell–cell interaction and cell migration. Ephrins are the ligands to Eph receptors and stimulate bi-directional signaling of the Eph/ephrin axis. Eph receptor and ephrin overexpression can result in tumorigenesis as related to tumor growth and survival and is associated with angiogenesis and metastasis in many types of human cancer. Recent data suggest that Eph/ephrin signaling could play an important role in the development of novel inhibition strategies and cancer treatments to potentially target this receptor tyrosine kinase and/or its ligand. A deeper understanding of the molecular basis for normal versus defective cell–cell interaction through the Eph/ephrin axis will enable the potential development of novel cancer treatments. This review emphasizes the biology of Eph/ephrin as well as the potential for novel targeted therapy through this pathway.