CD4+ T cells support polyfunctionality of cytotoxic CD8+ T cells with memory potential in immunological control of tumor

Polyfunctionality/multifunctionality of effector T cells at the single cell level has been shown as an important parameter to predict the quality of T cell response and immunological control of infectious disease and malignancy. However, the fate of polyfunctional CD8⁺ CTLs and the factors that control the polyfunctionality of T cells remain largely unknown. Here we show that the acquisition of polyfunctionality on the initial stimulation is a sensitive immune correlate of CTL survival and memory formation. CD8⁺ T cells with high polyfunctionality, assessed with γ‐interferon and tumor necrosis factor‐α production and surface mobilization of the degranulation marker CD107a, showed enhanced Bcl‐2 expression, low apoptosis, and increased CD127^highKLRG1^low memory precursor phenotype. Consistent with these observations, CD8⁺ T cells were found to acquire high frequency of cells with polyfunctionality when stimulated in conditions known to enhance memory formation, such as the presence of CD4⁺ T cells, interleukin (IL)‐2, or IL‐21. Utilizing T‐cell receptor (TCR) transgenic mouse‐derived CD8⁺ T cells that express a TCR specific for a tumor‐derived neoantigen, we showed that polyfunctional tumor‐specific CTLs generated in the presence of CD4⁺ T cells showed long persistence in vivo and induced enhanced tumor regression when adoptively transferred into mice with progressing tumor. Acquisition of polyfunctionality thus impacts CTL survival and memory formation associated with immunological control of tumor.     

CD4+CD25+调节性T细胞与抗肿瘤免疫

CD4^＋CD25^＋调节性T（CD4^＋CD25^＋Tr）细胞是一类维持机体自身耐受的T细胞亚群,分布广泛,但不同组织表型有所不同。它们可由胸腺自然产生,也可在外周血中诱导产生,其活化要依赖于特异性抗原的存在。CD4^＋CD25^＋Tr细胞发挥抑制效应是通过细胞接触依赖或分泌细胞因子这两种方式。去除CD4^＋CD25^＋Tr细胞或抑制其功能,重新募集效应性T细胞能够增强机体抗肿瘤作用,这将成为一种可行的肿瘤免疫治疗方法。     

CD4+CD25+调节性T细胞及其在肿瘤免疫治疗中的意义

CD4^＋ CD25^＋调节性T细胞是具有独特免疫调节功能的T细胞亚群。近年来研究发现各种恶性肿瘤患者外周血及肿瘤环境中该细胞比例增加，去除CD4^＋ CD25^＋调节性T细胞或封闭其抑制功能可以增强抗肿瘤免疫反应。CD4^＋ CD25^＋调节性T细胞成为肿瘤免疫治疗的新靶点。     

The impact of CD4+CD25+ Treg on tumor specific CD8+ T cell cytotoxicity and cancer

There is sufficient evidence to suggest that tumor growth elicits specific immune responses, including CD8(+) and CD4(+) T cell responses that may delay tumor growth and could potentially be harnessed to eradicate cancer. Nevertheless the frequent outcome of cancer is lethality associated with uncontrolled growth and dissemination of tumor cells. The failure of the immune response may be naturally programmed and related to a specific subpopulation of CD4(+)CD25(+) regulatory T cells, whose function is to protect us against autoimmunity. Recent investigations have shed light on the in vivo behavior and functions of these cells. It is becoming evident that a major impact of these cells is on the cytolytic action of specific CD8(+) T cells that target the tumor. Inhibition of cytotoxicity is dependent on TGF-beta signaling by the effector cells. Thus, targeting immune regulation may provide a promising approach to the immune therapy of cancer. This approach however could also have unexpected deleterious consequences, as surprising new observations indicate that regulatory T cells can also delay tumor growth by independent mechanisms that relate to their cross talk with the innate immune response to cancer.     

CD4+CD25+调节性T细胞与CD4+T、CD8+T细胞在结直肠癌组织中的分布

 目的 分析CD4+CD25+ FOXP3+调节性T细胞（Treg）与CD4+T、CD8+T在结直肠癌（colorectal carcinoma, CRC）组织中的分布及其与临床病理特征之间的关系。方法 收集42例CRC新鲜手术标本,应用冰冻切片、免疫组织化学SP法检测肿瘤组织和癌旁组织中FOXP3+、CD4+T和CD8+T阳性细胞数。结果 CRC患者肿瘤组织中FOXP3表达水平显著升高,与癌旁组织相比差异有统计学意义（P<0.01）;中低分化组Treg细胞数明显高于高分化组（P<0.01）;淋巴结转移组Treg细胞数明显高于无淋巴结转移组（P<0.05）;癌巢内CD4+、CD8+T细胞数及CD4+/CD8+值显著低于间质（P<0.01）;Ⅲ+Ⅳ期、淋巴结转移组癌巢内CD4+/CD8+比值显著低于Ⅰ+Ⅱ期及无淋巴结转移组（P<0.05）;CRC中Treg数量与癌巢内CD4+/CD8+比值显著负相关（r=-0.605, P<0.01）。结论 CRC的发生发展可能与其癌组织局部微环境中Treg数量变化相关,肿瘤局部Treg数量的增多与T淋巴细胞亚群比例失调可能成为肿瘤免疫逃逸的机制之一。     

CD4+CD25+CCR6+调节性T细胞在小鼠乳腺癌模型中对CD8+T细胞的抑制作用

目的：观察CD4+CD25+CCR6+调节性T细胞（简称CCR6+Tregs）体内对CD8+T细胞功能的抑制作用,并探讨其与肿瘤免疫逃逸的关系。方法：建立4T1乳腺癌细胞荷瘤裸鼠模型,FACS分选CCR6+Tregs,检测其Foxp3的表达;FACS分选4T1特异性CD8+T细胞,CFSE标记后分别与CCR6+Tregs或CCR6Tregs共同过继转输入4T1荷瘤裸鼠体内,观察荷瘤裸鼠肿瘤生长情况和小鼠存活时间;FACS检测肿瘤组织中CD8+T细胞的增殖、细胞因子IFNγ的产生和颗粒酶B的表达情况。结果：CCR6+Tregs和CCR6Tregs均高表达Foxp3;CCR6+Tregs和CD8+T细胞共转输组4T1荷瘤裸鼠肿瘤的生长明显快于CCR6Tregs共转输组和CD8+T细胞单转输组,同时该组荷瘤裸鼠生存时间也明显缩短（P<0.05）;CCR6+Tregs和CD8+T细胞共转输组CD8+T细胞的增殖、IFNγ的产生和颗粒酶B的表达均明显低于CCR6Tregs共转输组和CD8+T细胞单转输组（P<0.05）。结论：CCR6+Tregs在体内可以有效抑制CD8+T细胞的功能,其在肿瘤免疫逃逸和肿瘤发生、发展中发挥重要作用。     

CD+4CD+25调节性T细胞与肿瘤免疫

 近期研究发现一个有独特免疫调节功能的T细胞亚群：CD+4 CD+25调节性T细胞,不仅能抑制自身免疫性疾病发生,还参与肿瘤免疫的调节。这群细胞具有免疫无能和免疫抑制特性,与肿瘤免疫逃逸有密切的关系。肿瘤环境中CD+4 CD+25调节性T细胞增加,导致肿瘤免疫失调,去除这群细胞可有效诱导肿瘤免疫,为肿瘤治疗提供了一种新的思路。     

Induction of CD4+ and CD8+ anti‐tumor effector T cell responses by bacteria mediated tumor therapy

Facultative anaerobic bacteria like E. coli can colonize solid tumors often resulting in tumor growth retardation or even clearance. Little mechanistic knowledge is available for this phenomenon which is however crucial for optimization and further implementation in the clinic. Here, we show that intravenous injections with E. coli TOP10 can induce clearance of CT26 tumors in BALB/c mice. Importantly, re‐challenging mice which had cleared tumors showed that clearance was due to a specific immune reaction. Accordingly, lymphopenic mice never showed tumor clearance after infection. Depletion experiments revealed that during induction phase, CD8⁺ T cells are the sole effectors responsible for tumor clearance while in the memory phase CD8⁺ and CD4⁺ T cells were involved. This was confirmed by adoptive transfer. CD4⁺ and CD8⁺ T cells could reject newly set tumors while CD8⁺ T cells could even reject established tumors. Detailed analysis of adoptively transferred CD4⁺ T cells during tumor challenge revealed expression of granzyme B, FasL, TNF‐α and IFN‐γ in such T cells that might be involved in the anti‐tumor activity. Our findings should pave the way for further optimization steps of this promising therapy.     

CD8+ T cells regulate bone tumor burden independent of osteoclast resorption

Blockade of osteoclast (OC) activity efficiently decreases tumor burden as well as associated bone erosion in immune-compromised animals bearing human osteolytic cancers. In this study, we showed that modulation of antitumor T-cell responses alters tumor growth in bone, regardless of OC status, by using genetic and pharmacologic models. PLCγ2(-/-) mice, with dysfunctional OCs and impaired dendritic cell (DC)-mediated T-cell activation, had increased bone tumor burden despite protection from bone loss. In contrast, Lyn(-/-) mice, with more numerous OCs and a hyperactive myeloid population leading to increased T-cell responses, had reduced tumor growth in bone despite enhanced osteolysis. The unexpected tumor/bone phenotype observed in PLCγ2(-/-) and Lyn(-/-) mice was transplantable, suggesting the involvement of an immune component. Consistent with this hypothesis, T-cell activation diminished skeletal metastasis whereas T-cell depletion enhanced it, even in the presence of zoledronic acid, a potent antiresorptive agent. Importantly, injection of antigen-specific wild-type cytotoxic CD8(+) T cells in PLCγ2(-/-) mice or CD8(+) T-cell depletion in Lyn(-/-) mice normalized tumor growth in bone. Our findings show the important contribution of CD8(+) T cells in the regulation of bone metastases regardless of OC status, thus including T cells as critical regulators of tumor growth in bone.     

Regulatory CD8+ T cells control thyrotropin receptor-specific CD4+ clones in healthy subjects

One of the mechanisms ensuring immunological unresponsiveness or tolerance depends on the action of CD8(+) lymphocytes. In this paper, we report that, in healthy subjects, a subset of CD8(+)CD28(-) T cells suppresses the specific response to TSH receptor (TSHR) of CD4(+) clones. Suppression was highly specific, required cell-cell interaction, and was not mediated by cytotoxicity. Co-incubation of CD8(+) and CD4(+) clones, followed by the removal of the CD8(+) cells from the cultures before testing CD4(+) responsiveness to TSHR, demonstrated that CD4(+) cells were anergic since they showed low response to the antigen and a significant impairment of IL-2 production. In CD8-mediated anergy induction, the T-cell receptor (TCR) on both CD4(+) and CD8(+) cells seems to play a role. Our results indicate that one of the mechanisms ensuring peripheral tolerance involve CD8(+)CD28(-) cells. A disregulation in the control of autoreactive clones by this subset might be important for the onset of autoimmune thyroid diseases.     

CD4~+ CD25~+调节性T细胞及其在肿瘤免疫治疗中的意义

CD4+CD25+调节性T细胞是具有独特免疫调节功能的T细胞亚群。近年来研究发现各种恶性肿瘤患者外周血及肿瘤环境中该细胞比例增加,去除CD4+CD25+调节性T细胞或封闭其抑制功能可以增强抗肿瘤免疫反应。CD4+CD25+调节性T细胞成为肿瘤免疫治疗的新靶点。     

Sustained antigen-specific antitumor recall response mediated by gene-modified CD4+ T helper-1 and CD8+ T cells

Given that specific subsets of T helper 1 (Th1) and T helper 2 (Th2) CD4(+) T cells have been shown to play key roles in tumor rejection models, we wanted to assess the contribution of either Th1 or Th2 CD4(+) cell subtypes for redirected T-cell immunotherapy. In this study, we have developed a novel method involving retroviral transduction and in vitro T-cell polarization to generate gene-engineered mouse CD4(+) Th1 and Th2 cells or T helper intermediate (Thi) cells expressing an anti-erbB2-CD28-zeta chimeric receptor. Gene-modified Th1 and Th2 polarized CD4(+) cells were characterized by the preferential secretion of IFN-gamma and interleukin-4, respectively, whereas Thi cells secreted both cytokines following receptor ligation. In adoptive transfer studies using an erbB2(+) lung metastasis model, complete survival of mice was observed when transduced Th1, Th2, or Thi CD4(+) cells were transferred in combination with an equivalent number of transduced CD8(+) T cells. Tumor rejection was consistently associated with transduced T cells at the tumor site and interleukin-2 secretion. However, the surviving mice treated with gene-modified Th1 CD4(+) cells were significantly more resistant to a subsequent challenge with a different erbB2(+) tumor (4T1.2) implanted s.c. This result correlated with both increased expansion of Th1 CD4(+) and CD8(+) T cells in the blood and a greater number of these cells localizing to the tumor site following rechallenge. These data support the use of gene-modified CD4(+) Th1 and CD8(+) T cells for mediating a sustained antitumor response.     

CD4+ and CD8+ T cells have opposing roles in breast cancer progression and outcome

The Cancer Immunoediting concept has provided critical insights suggesting dual functions of immune system during the cancer initiation and development. However, the dynamics and roles of CD4⁺ and CD8⁺ T cells in the pathogenesis of breast cancer remain unclear. Here we utilized two murine breast cancer models (4T1 and E0771) and demonstrated that both CD4⁺ and CD8⁺ T cells were increased and involved in immune responses, but with distinct dynamic trends in breast cancer development. In addition to cell number increases, CD4⁺ T cells changed their dominant subsets from Th1 in the early stages to Treg and Th17 cells in the late stages of the cancer progression. We also analyzed CD4⁺ and CD8⁺ T cell infiltration in primary breast cancer tissues from cancer patients. We observed that CD8⁺ T cells are the key effector cell population mediating effective anti-tumor immunity resulting in better clinical outcomes. In contrast, intra-tumoral CD4⁺ T cells have negative prognostic effects on breast cancer patient outcomes. These studies indicate that CD4⁺ and CD8⁺ T cells have opposing roles in breast cancer progression and outcomes, which provides new insights relevant for the development of effective cancer immunotherapeutic approaches.     

CD4+ T cells are able to promote tumor growth through inhibition of tumor-specific CD8+ T-cell responses in tumor-bearing hosts

Modulation of the immune response by established tumors may contribute to the limited success of therapeutic vaccination for the treatment of cancer compared with vaccination in a preventive setting. We analyzed the contribution of the CD4+ T-cell population to the induction or suppression of tumor-specific CD8+ T cells in a tumor model in which eradication of tumors crucially depends on CD8+ T cell-mediated immunity. Vaccine-mediated induction of protective antitumor immunity in the preventive setting (i.e., before tumor challenge) was CD4+ T cell dependent because depletion of this T-cell subset prevented CD8+ T-cell induction. In contrast, depletion of CD4+ cells in mice bearing established E1A+ tumors empowered the mice to raise strong CD8+ T-cell immunity capable of tumor eradication without the need for tumor-specific vaccination. Spontaneous eradication of tumors, which had initially grown out, was similarly observed in MHC class II-deficient mice, supporting the notion that the tumor-bearing mice harbor a class II MHC-restricted CD4+ T-cell subset capable of suppressing a tumor-specific CD8+ T-cell immune response. The deleterious effects of the presence of CD4+ T cells in tumor-bearing hosts could be overcome by CD40-triggering or injection of CpG. Together these results show that CD4+ T cells with a suppressive activity are rapidly induced following tumor development and that their suppressive effect can be overcome by agents that activate professional antigen-presenting cells. These observations are important for the development of immune interventions aiming at treatment of cancer.     

Concurrent infiltration by CD8+ T cells and CD4+ T cells is a favourable prognostic factor in non-small-cell lung carcinoma

The purpose of this study was to clarify the relationship between the number of tumour-infiltrating T lymphocytes and the clinicopathological features and clinical outcome in patients with non-small-cell lung cancer (NSCLC). Tissue specimens from 109 patients who underwent surgical resection for NSCLC were immunohistochemically analysed for CD4 and CD8 expression. Patients were classified into two groups according to whether their tumours exhibited a 'high' or 'low' level of CD8(+) or CD4(+) lymphocyte infiltration. Although the level of infiltration by CD8(+) T cells alone had no prognostic significance, the survival rate for patients with both 'high' CD8(+) and 'high' CD4(+) T-cell infiltration was significantly higher than that for the other groups (log-rank test, P=0.006). Multivariate analysis indicated that concomitant high CD8(+) and high CD4(+) T-cell infiltration was an independent favourable prognostic factor (P=0.0092). In conclusion, the presence of high levels of both CD8(+) T cells and CD4(+) T cells is a significant indicator of a better prognosis for patients with NSCLC, and cooperation between these cell populations may allow a significantly more potent antitumour response than either population alone.     

CD8+ T cells inhibit metastasis and CXCL4 regulates its function

Background The mechanism by which immune cells regulate metastasis is unclear. Understanding the role of immune cells in metastasis will guide the development of treatments improving patient survival.Methods We used syngeneic orthotopic mouse tumour models (wild-type, NOD/scid and Nude), employed knockout (CD8 and CD4) models and administered CXCL4. Tumours and lungs were analysed for cancer cells by bioluminescence, and circulating tumour cells were isolated from blood. Immunohistochemistry on the mouse tumours was performed to confirm cell type, and on a tissue microarray with 180 TNBCs for human relevance. TCGA data from over 10,000 patients were analysed as well.Results We reveal that intratumoral immune infiltration differs between metastatic and non-metastatic tumours. The non-metastatic tumours harbour high levels of CD8⁺ T cells and low levels of platelets, which is reverse in metastatic tumours. During tumour progression, platelets and CXCL4 induce differentiation of monocytes into myeloid-derived suppressor cells (MDSCs), which inhibit CD8⁺ T-cell function. TCGA pan-cancer data confirmed that CD8^lowPlatelet^high patients have a significantly lower survival probability compared to CD8^highPlatelet^low.Conclusions CD8⁺ T cells inhibit metastasis. When the balance between CD8⁺ T cells and platelets is disrupted, platelets produce CXCL4, which induces MDSCs thereby inhibiting the CD8⁺ T-cell function.Subject terms: Tumour immunology, Metastasis     

肝癌微环境中CD4~+CD25~+调节性T细胞与T细胞免疫的关系

目的:探讨肝细胞癌组织中CD4 CD25 调节性T细胞(CD4 CD25 regulartory Tcell,Treg)与肿瘤微环境T细胞免疫的关系。方法:对52例肝细胞癌组织和癌旁组织用CD4、CD25双重酶标免疫组化染色和用CD8 EnVision法染色,对癌组织中Treg细胞和CD4 T、CD8 T、CD4 T/CD8 T比值进行相关性分析。结果:正常肝脏组织中未发现Treg细胞,肝癌和癌旁组织中Treg细胞单个高倍视野平均数分别为(7.6±2.84)、(5.2±1.67),两组比较有显著差异(P<0.01);肝癌及癌旁组织中CD4 T细胞单个高倍视野平均数分别为(18.2±3.57)、(25.9±3.36),两组比较有显著差异(P<0.01);肝癌及癌旁组织中CD8 T细胞单个高倍视野平均数分别为(49.9±6.61)、(49.5±6.43),两组比较无明显差异;肝癌及癌旁组织中CD4 T/CD8 T比值分别为(0.37±0.08)、(0.53±0.09),两组比较有显著差异(P<0.01);肝癌组织中Treg细胞的数量与其浸润性CD4 T淋巴细胞的数量及CD4 T/CD8 T比值呈显著负相关(P<0.01),而与浸润性CD8 T淋巴细胞的数量分布无明显相关性。结论∶Treg细胞在肝癌微环境中可能通过抑制CD4 T淋巴细胞的增殖来抑制肿瘤局部免疫。     

肿瘤外泌体对CD8+T细胞功能的影响及机制研究进展

外泌体（exosomes）是介导细胞间通讯的细胞外囊泡。它携带来源细胞的多种生物活性分子,并可将其输送给受体细胞,进而影响细胞功能。肿瘤来源外泌体可通过多种机制介导肿瘤的免疫逃逸。本文就肿瘤外泌体对肿瘤杀伤主力军CD8+T细胞的调控作用进行总结,分析其相关作用机制,以期为肿瘤免疫治疗的研发提供新的思路。     

Human and viral interleukin-10 in Hodgkin's disease,and its influence on CD4+ and CD8+ T lymphocytes

The Epstein-Barr virus (EBV) is closely related to Hodgkin's disease (HD), while the BCRF-I (viral [v] IL-10) gene of the EBV is highly homologous to the human interleukin-10 (h IL-10) gene. To investigate the relationship of IL-10 and HD, we performed both immunostaining and in situ hybridization (ISH) in 30 cases of HD. The presence of EBV in Hodgkin (H) and Reed-Sternberg (RS) cells was seen in 16 of the 30 cases, by ISH of the EBV EBER-I region and/or immunostaining of latent membrane protein (LMP-I). Of the 16 EBV-positive cases, 12 also showed IL-10 antigen (Ag) in H and RS cells by immunostaining, 5 of the 16 demonstrated hIL-10 RNA by ISH and 14 of the 16 showed vIL-10 RNA. But only 2 of the 14 EBV-negative cases showed IL-10 Ag, and one of them showed hIL-10 RNA, while none demonstrated vIL-10 RNA. The T cells in the HD-involved tissues were found to be mainly CD4-positive T cells, and had no association with EBV infection. However, the lymphocytes surrounding H and RS cells were more frequently CD4 cells and rarely CD8 cells in the EBV-positive cases, in contrast with the EBV-negative cases. The above results indicate that an EBV infection influenced both cytokine synthesis and the response of T cells in HD. © 1995 Wiley-Liss Inc.