共查询到20条相似文献，搜索用时 31 毫秒
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Beatrice Ondondo Emily Colbeck Emma Jones Kathryn Smart Sarah N Lauder James Hindley Andrew Godkin Bernhard Moser Ann Ager Awen Gallimore 《Immunology》2015,145(1):94-104
The frequency of CD4+ Foxp3+ regulatory T (Treg) cells is often significantly increased in the blood of tumour-bearing mice and people with cancer. Moreover, Treg cell frequencies are often higher in tumours compared with blood and lymphoid organs. We wished to determine whether certain chemokines expressed within the tumour mass selectively recruit Treg cells, thereby contributing to their enrichment within the tumour-infiltrating lymphocyte pool. To achieve this goal, the chemokine profile of carcinogen-induced fibrosarcomas was determined, and the chemokine receptor expression profiles of both CD4+ Foxp3− and CD4+ Foxp3+ T cells were compared. These analyses revealed that the tumours are characterized by expression of inflammatory chemokines (CCL2, CCL5, CCL7, CCL8, CCL12, CXCL9, CXCL10 and CX3CL1), reflected by an enrichment of activated Foxp3− and Foxp3+ T cells expressing T helper type 1-associated chemokine receptors. Notably, we found that CXCR3+ T cells were significantly enriched in the tumours although curiously we found no evidence that CXCR3 was required for their recruitment. Instead, CXCR3 marks a population of activated Foxp3− and Foxp3+ T cells, which use multiple and overlapping ligand receptor pairs to guide their migration to tumours. Collectively, these data indicate that enrichment of Foxp3+ cells in tumours characterized by expression of inflammatory chemokines, does not occur via a distinct chemokine axis, thus selective chemokine blockade is unlikely to represent a meaningful therapeutic strategy for preventing Treg cell accumulation in tumours. 相似文献
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The most potent killing machinery in our immune system is the cytotoxic T lymphocyte (CTL). Since the possibility for self-destruction by these cells is high, many regulatory activities exist to prevent autoimmune destruction by these cells. A tumour (cancer) grows from the cells of the body and is tolerated by the body''s immune system. Yet, it has been possible to generate tumour-associated antigen (TAA) -specific CTL that are also self-antigen specific in vivo, to achieve a degree of therapeutic efficacy. Tumour-associated antigen-specific T-cell tolerance through pathways of self-tolerance generation represents a significant challenge to successful immunotherapy. CD4+ CD25+ FoxP3+ T cells, referred to as T regulatory (Treg) cells, are selected in the thymus as controllers of the anti-self repertoire. These cells are referred to as natural T regulatory (nTreg) cells. According to the new consensus (Nature Immunology 2013; 14:307–308) these cells are to be termed as (tTreg). There is another class of CD4+ Treg cells also involved in regulatory function in the periphery, also phenotypically CD4+ CD25±, classified as induced Treg (iTreg) cells. These cells are to be termed as peripherally induced Treg (pTreg) cells. In vitro-induced Treg cells with suppressor function should be termed as iTreg. These different Treg cells differ in their requirements for activation and in their mode of action. The current challenges are to determine the degree of specificity of these Treg cells in recognizing the same TAA as the CTL population and to circumvent their regulatory constraints so as to achieve robust CTL responses against cancer. 相似文献
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The presence of tumour-infiltrating immune cells was originally associated with the induction of anti-tumour responses and good a prognosis. A more refined characterization of the tumour microenvironment has challenged this original idea and evidence now exists pointing to a critical role for immune cells in the modulation of anti-tumour responses and the induction of a tolerant pro-tumour environment. The coordinated action of diverse immunosuppressive populations, both innate and adaptive, shapes a variety of pro-tumour responses leading to tumour progression and metastasis. Regulatory B cells have emerged as critical modulators and suppressors of anti-tumour responses. As reported in autoimmunity and infection studies, Bregs are a heterogeneous population with diverse phenotypes and different mechanisms of action. Here we review recent studies on Bregs from animal models and patients, covering a variety of types of cancer. We describe the heterogeneity of Bregs, the cellular interactions they make with other immune cells and the tumour itself, and their mechanism of suppression that enables tumour escape. We also discuss the potential therapeutic tools that may inhibit Bregs function and promote anti-tumour responses. 相似文献
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《Immunology》2017,152(2):175-184
Altered metabolism is a hallmark of cancers, including shifting oxidative phosphorylation to glycolysis and up‐regulating glutaminolysis to divert carbon sources into biosynthetic pathways that promote proliferation and survival. Therefore, metabolic inhibitors represent promising anti‐cancer drugs. However, T cells must rapidly divide and survive in harsh microenvironments to mediate anti‐cancer effects. Metabolic profiles of cancer cells and activated T lymphocytes are similar, raising the risk of metabolic inhibitors impairing the immune system. Immune checkpoint blockade provides an example of how metabolism can be differentially impacted to impair cancer cells but support T cells. Implications for research with metabolic inhibitors are discussed. 相似文献
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Cancer immunotherapy focuses mainly on anti‐tumour activity of CD8+ cytotoxic T lymphocytes (CTLs). CTLs can directly kill all tumour cell types, provided they carry recognizable antigens. However, CD4+ T cells also play important roles in anti‐tumour immunity. CD4+ T cells can either suppress or promote the anti‐tumour CTL response, either in secondary lymphoid organs or in the tumour. In this review, we highlight opposing mechanisms of conventional and regulatory T cells at both sites. We outline how current cancer immunotherapy strategies affect both subsets and how selective modulation of each subset is important to maximize the clinical response of cancer patients. 相似文献
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The inflammatory response to transformed cells forms the cornerstone of natural or therapeutically induced protective immunity to cancer. Regulatory T (Treg) cells are known for their critical role in suppressing inflammation, and therefore can antagonize effective anti-cancer immune responses. As such, Treg cells can play detrimental roles in tumour progression and in the response to both conventional and immune-based cancer therapies. Recent advances in our understanding of Treg cells reveal complex niche-specific regulatory programmes and functions, which are likely to extrapolate to cancer. The regulation of Treg cells is reliant on upstream cues from haematopoietic and non-immune cells, which dictates their genetic, epigenetic and downstream functional programmes. In this review we will discuss how Treg cells are themselves regulated in normal and transformed tissues, and the implications of this cross talk on tumour growth. 相似文献
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Ângela Fernandes Catarina M. Azevedo Mariana C. Silva Guilherme Faria Carolina S. Dantas Manuel M. Vicente Salomé S. Pinho 《Immunology》2023,168(2):217-232
Essentially all cells are covered with a dense coat of different glycan structures/sugar chains, giving rise to the so-called glycocalyx. Changes in cellular glycosylation are a hallmark of cancer, affecting most of the pathophysiological processes associated with malignant transformation, including tumour immune responses. Glycans are chief macromolecules that define T-cell development, differentiation, fate, activation and signalling. Thus, the diversity of glycans expressed at the surface of T cells constitutes a fundamental molecular interface with the microenvironment by regulating the bilateral interactions between T-cells and cancer cells, fine-tuning the anti-tumour immune response. In this review, we will introduce the power of glycans as orchestrators of T-cell-mediated immune response in physiological conditions and in cancer. We discuss how glycans modulate the glyco-metabolic landscape in the tumour microenvironment, and whether glycans can synergize with immunotherapy as a way of rewiring T-cell effector functions against cancer cells. 相似文献
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Tumour infiltration by regulatory T (Treg) cells contributes to suppression of the anti-tumour immune response, which limits the efficacy of immune-mediated cancer therapies. The phosphoinositide 3-kinase (PI3K) pathway has key roles in mediating the function of many immune cell subsets, including Treg cells. Treg function is context-dependent and depends on input from different cell surface receptors, many of which can activate the PI3K pathway. In this review, we explore how PI3Kδ contributes to signalling through several major immune cell receptors, including the T-cell receptor and co-stimulatory receptors such as CD28 and ICOS, but is antagonized by the immune checkpoint receptors CTLA-4 and PD-1. Understanding how PI3Kδ inhibition affects Treg signalling events will help to inform how best to use PI3Kδ inhibitors in clinical cancer treatment. 相似文献
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J Fenn L A Ridgley A White C Sarfas M Dennis A Dalgleish R Reljic S Sharpe M Bodman-Smith 《Clinical and experimental immunology》2022,208(3):301
Vδ2+ T cells can recognize malignantly transformed cells as well as those infected with mycobacteria. This cross-reactivity supports the idea of using mycobacteria to manipulate Vδ2+ T cells in cancer immunotherapy. To date, therapeutic interventions using Vδ2+ T cells in cancer have involved expanding these cells in or ex vivo using zoledronic acid (ZA). Here, we show that the mycobacterium Bacillus Calmette–Guérin (BCG) also causes Vδ2+ T-cell expansion in vitro and that resulting Vδ2+ cell populations are cytotoxic toward tumour cell lines. We show that both ZA and BCG-expanded Vδ2+ cells effectively killed both Daudi and THP-1 cells. THP-1 cell killing by both ZA and BCG-expanded Vδ2+ cells was enhanced by treatment of targets cells with ZA. Although no difference in cytotoxic activity between ZA- and BCG-expanded Vδ2+ cells was observed, BCG-expanded cells degranulated more and produced a more diverse range of cytokines upon tumour cell recognition compared to ZA-expanded cells. ZA-expanded Vδ2+ cells were shown to upregulate exhaustion marker CD57 to a greater extent than BCG-expanded Vδ2+ cells. Furthermore, ZA expansion was associated with upregulation of inhibitory markers PD-1 and TIM3 in a dose-dependent manner whereas PD-1 expression was not increased following expansion using BCG. Intradermal BCG vaccination of rhesus macaques caused in vivo expansion of Vδ2+ cells. In combination with the aforementioned in vitro data, this finding suggests that BCG treatment could induce expansion of Vδ2+ T cells with enhanced anti-tumour potential compared to ZA treatment and that either ZA or BCG could be used intratumourally as a means to potentiate stronger anti-tumour Vδ2+ T-cell responses. 相似文献
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R. A. M. Wilson T. R. J. Evans A. R. Fraser R. J. B. Nibbs 《Clinical and experimental immunology》2018,191(2):133-148
Immune checkpoint inhibitors (ICIs) targeting cytotoxic T lymphocyte‐associated protein‐4 (CTLA‐4) or programmed cell death protein 1 (PD‐1) receptors have demonstrated remarkable efficacy in subsets of patients with malignant disease. This emerging treatment modality holds great promise for future cancer treatment and has engaged pharmaceutical research interests in tumour immunology. While ICIs can induce rapid and durable responses in some patients, identifying predictive factors for effective clinical responses has proved challenging. This review summarizes the mechanisms of action of ICIs and outlines important preclinical work that contributed to their development. We explore clinical data that has led to disease‐specific drug licensing, and highlight key clinical trials that have revealed ICI efficacy across a range of malignancies. We describe how ICIs have been used as part of combination therapies, and explore their future prospects in this area. We conclude by discussing the incorporation of these new immunotherapeutics into precision approaches to cancer therapy. 相似文献
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Hannah Richards Anwen Williams Emma Jones James Hindley Andrew Godkin Anna Katharina Simon Awen Gallimore 《Immunology》2010,131(4):583-592
It is clear that CD4+ CD25+ Foxp3+ regulatory T (Treg) cells inhibit chronic inflammatory responses as well as adaptive immune responses. Among the CD4+ T‐cell population in the skin, at least one‐fifth express Foxp3. As the skin is constantly exposed to antigenic challenge and is a common site of vaccination, understanding the role of these skin‐resident Treg cells is important. Although the suppressive effect of Treg cells on T cells is well documented, less is known about the types of innate immune cells influenced by Treg cells and whether the Treg cells suppress acute innate immune responses in vivo. To address this we used a mouse melanoma cell line expressing Fas ligand (B16FasL), which induces an inflammatory response following subcutaneous injection of mice. We demonstrate that Treg cells limit this response by inhibiting neutrophil accumulation and survival within hours of tumour cell inoculation. This effect, which was associated with decreased expression of the neutrophil chemoattractants CXCL1 and CXCL2, promoted survival of the inoculated tumour cells. Overall, these data imply that Treg cells in the skin are rapidly mobilized and that this activity serves to limit the amplification of inflammatory responses at this site. 相似文献
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A. Skowera K. Ladell K. Tungatt E. Jones D. Kronenberg‐Versteeg H. Akpovwa J. M. Pentier C. J. Holland A. J. Godkin D. K. Cole M. A. Neller J. J. Miles D. A. Price M. Peakman A. K. Sewell 《Clinical and experimental immunology》2014,177(1):47-63
Fluorochrome‐conjugated peptide–major histocompatibility complex (pMHC) multimers are widely used for flow cytometric visualization of antigen‐specific T cells. The most common multimers, streptavidin–biotin‐based ‘tetramers’, can be manufactured readily in the laboratory. Unfortunately, there are large differences between the threshold of T cell receptor (TCR) affinity required to capture pMHC tetramers from solution and that which is required for T cell activation. This disparity means that tetramers sometimes fail to stain antigen‐specific T cells within a sample, an issue that is particularly problematic when staining tumour‐specific, autoimmune or MHC class II‐restricted T cells, which often display TCRs of low affinity for pMHC. Here, we compared optimized staining with tetramers and dextramers (dextran‐based multimers), with the latter carrying greater numbers of both pMHC and fluorochrome per molecule. Most notably, we find that: (i) dextramers stain more brightly than tetramers; (ii) dextramers outperform tetramers when TCR–pMHC affinity is low; (iii) dextramers outperform tetramers with pMHC class II reagents where there is an absence of co‐receptor stabilization; and (iv) dextramer sensitivity is enhanced further by specific protein kinase inhibition. Dextramers are compatible with current state‐of‐the‐art flow cytometry platforms and will probably find particular utility in the fields of autoimmunity and cancer immunology. 相似文献
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Ellyn Hughes Martin Scurr Emma Campbell Emma Jones Andrew Godkin Awen Gallimore 《Immunology》2018,154(1):62-68
The power of T cells for cancer treatment has been demonstrated by the success of co‐inhibitory receptor blockade and adoptive T‐cell immunotherapies. These treatments are highly successful for certain cancers, but are often personalized, expensive and associated with harmful side effects. Other T‐cell‐modulating drugs may provide additional means of improving immune responses to tumours without these disadvantages. Conventional chemotherapeutic drugs are traditionally used to target cancers directly; however, it is clear that some also have significant immune‐modulating effects that can be harnessed to target tumours. Cyclophosphamide is one such drug; used at lower doses than in mainstream chemotherapy, it can perturb immune homeostasis, tipping the balance towards generation of anti‐tumour T‐cell responses and control of cancer growth. This review discusses its growing reputation as an immune‐modulator whose multiple effects synergize with the microbiota to tip the balance towards tumour immunity offering widespread benefits as a safe, and relatively inexpensive component of cancer immunotherapy. 相似文献
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The ability to induce functional reprogramming of regulatory T (Treg) cells in the tumor microenvironment is an extremely important therapeutic opportunity. However, when discussing such an approach, the opposing effect that the activation of the Treg cell compartments may have in inducing the immune inflammatory response and its link with the efficacy of immunotherapy should be considered. In fact, Treg reprogramming has a dual effect: immediate, with mechanisms that activate immunosurveillance, and late, mediated by the macrophage activation that yields an inflammatory status that is deleterious for the antineoplastic efficiency of the immune system response. Persistence of the inflammatory response is associated with specific changes of oxidative and glycolytic metabolic pathways that interfere with conventional T-cell activation and function and may be one of the reasons for the failure of immunotherapy in advanced cancer patients. Therefore, in addition to modulating Treg cell action, the combined use of drugs able to block chronic inflammation mediated mainly by macrophages, to counteract the oxidative stress, and to positively regulate the metabolic derangements, could improve the effectiveness of modern immunotherapy. In conclusion, reprogramming of Treg cells may be an appropriate strategy for treating early stages of neoplastic diseases, whereas other immunosuppressive mechanisms should be the target of a combined immunotherapy approach in more advanced phases of cancer. 相似文献
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CD4+ CD25+ regulatory T cells in human pregnancy: development of a Treg-MLC-ELISPOT suppression assay and indications of paternal specific Tregs 
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下载免费PDF全文 The current study was aimed at developing a one-way mixed leucocyte culture-enzyme-linked immunospot (MLC-ELISPOT) assay for the study of CD4(+) CD25(+) regulatory T (T(reg)) cells and applying this method in the study of antifetal immune reactions during human pregnancy. Twenty-one pregnant women and the corresponding fathers-to-be, and 10 non-pregnant control women and men, participated in the study. CD4(+) CD25(+) cells were isolated from peripheral blood mononuclear cells (PBMC) by immunomagnetic selection. Maternal/control PBMC were stimulated with paternal or unrelated PBMC in MLC. Secretion of interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) from responder cells, with or without the presence of autologous T(reg) cells, was analysed by ELISPOT. PBMC from pregnant women showed increased secretion of IL-4 compared to controls. In pregnant and non-pregnant controls, T(reg) cells suppressed IFN-gamma reactivity against paternal and unrelated alloantigens. Interestingly, T(reg) cells suppressed IL-4 secretion against paternal but not unrelated alloantigens during pregnancy. We have successfully developed a model for studying T(reg) cells in antifetal cytokine reactions during pregnancy. Results indicate that T(reg) cells contribute to strict regulation of both T helper type 1-like and type 2-like antifetal immune reactions. Interestingly, T helper type 2-like cells specific to unrelated alloantigens are able to escape the suppression of T(reg) cells, which would allow for IL-4, alongside CD4(+) CD25(+) T(reg) cells, to control potentially detrimental IFN-gamma reactions during pregnancy. 相似文献
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目的：探讨CD4＋CD25＋调节性T细胞在胃癌患者外周血分布的临床意义及其作用机制。方法流式细胞术分析不同TNM分期的胃癌患者和健康者外周血CD4＋CD25＋调节性T细胞的比例。免疫磁珠分离胃癌患者和健康者外周血CD4＋CD25＋调节性T细胞,将CD4＋CD25＋调节性T细胞与淋巴细胞体外共培养, CCK8方法检测CD4＋CD25＋调节性T细胞对淋巴细胞的增殖能力的影响。 RT?PCR检测CD4＋CD25＋调节性T细胞特异性转录因子Foxp3 mRNA的表达水平。结果胃癌患者外周血CD4＋CD25＋调节性T细胞的比例明显高于健康者,差异具有统计学意义（P＜0．05）。其中Ⅲ期和Ⅳ期胃癌患者外周血调节性T细胞的比例均明显高于Ⅰ?Ⅱ期胃癌患者,差异具有统计学意义（ P ＜0．05）。与健康者相比,胃癌患者 CD4＋CD25＋调节性T细胞能明显抑制淋巴细胞增殖,其差异具有统计学意义（ P＜0．05）,而且Ⅲ期和Ⅳ期胃癌患者CD4＋CD25＋调节性T细胞抑制淋巴细胞增殖的能力明显强于Ⅰ?Ⅱ期胃癌患者,其差异具有统计学意义（P＜0．05）。进一步分析显示胃癌患者CD4＋CD25＋调节性T细胞Foxp3 mRNA的表达水平均明显高于健康者,差异具有统计学意义（P＜0．05）。其中Ⅲ期和Ⅳ期胃癌患者Foxp3 mRNA的表达水平明显高于Ⅰ?Ⅱ期胃癌患者,其差异具有统计学意义（P＜0．05）。结论调节性T细胞可能通过增强Foxp3 mRNA表达发挥免疫抑制作用,促进胃癌的发生发展。通过监测外周血调节性T细胞有利于评估胃癌患者免疫功能和病情进展。 相似文献
