CD4+T细胞与肿瘤免疫

在肿瘤免疫中细胞免疫发挥着重要作用,其中T细胞介导的特异性免疫应答反应更为重要.近年来CD4+T细胞在抗肿瘤免疫中的作用越来越受到重视.在肿瘤免疫中CD4+T细胞启动后可以通过多种机制启动细胞毒性T淋巴细胞(CTL),维持和加强CTL的抗肿瘤反应,并且可以作为效应细胞发挥抗肿瘤作用,CD4+T细胞中的一个亚群细胞CD4+ CD25+T调节细胞对肿瘤免疫有抑制作用.     

CD4+T细胞与肿瘤免疫

在肿瘤免疫中细胞免疫发挥着重要作用,其中T细胞介导的特异性免疫应答反应更为重要.近年来CD4+T细胞在抗肿瘤免疫中的作用越来越受到重视.在肿瘤免疫中CD4+T细胞启动后可以通过多种机制启动细胞毒性T淋巴细胞(CTL),维持和加强CTL的抗肿瘤反应,并且可以作为效应细胞发挥抗肿瘤作用,CD4+T细胞中的一个亚群细胞CD4+ CD25+T调节细胞对肿瘤免疫有抑制作用.     

CD4~+T 细胞与肿瘤免疫

CD4~+T细胞不仅辅助激活CD8~+T细胞,而且对记忆性细胞毒性T淋巴细胞(CTL)应答的产生和维持起重要作用,并具有直接的抗肿瘤功能.另外,CD4~+CD25~+ 调节性T细胞(Tregs)具有免疫负调控功能,在肿瘤免疫抑制及免疫逃逸中发挥重要作用,是肿瘤免疫治疗失败的重要原因.近年肿瘤免疫治疗已获得很大进步,相关肿瘤疫苗的研究也备受关注.     

CD4+T细胞在肝细胞癌中的作用

CD4+T细胞为一系列多功能细胞,研究发现肝细胞癌(HCC)中大部分CD4+T细胞亚群可通过活化或抑制机体固有免疫细胞、适应性免疫细胞及非免疫细胞等,参与肿瘤血管生成及浸润、肿瘤细胞凋亡、急性期蛋白及促癌基因的表达,进而发挥肿瘤促进或抑制作用.     

CD4+ T lymphocytes: a critical component of antitumor immunity

Both prophylactic and therapeutic vaccines targeting a wide variety of cancers are being developed. Because of the potency of cell-mediated immunity, many vaccine strategies are focused on activating tumor-specific cytotoxic CD8⁺ T lymphocytes. CD4⁺ T lymphocytes are a key element in optimal activation of CD8⁺ T cells and in the maintenance of immune memory, and therefore their activation is critical for cancer vaccine efficacy. This article reviews the mechanisms by which CD4⁺ T cells facilitate tumor immunity and the vaccine strategies that enhance CD4⁺ T cell activity.     

The effect of cimetidine mainly increases CD4+ cells of peripheral blood T lymphocytes

Cimetidine, one of the most popular histamine-2 receptor antagonists, has been reported to improve survival in gastrointestinal cancer patients and to activate cell-mediated immune response in surgical patients. NKT cells are a population of T cells that share characteristics with natural killer cells, and their main functions are production of immunoregulatory cytokines and cytolytic activities. In this study, we aimed to investigate the effect of cimetidine on the cell-mediated immunoresponse. Six healthy adult volunteers were given 800 mg of cimetidine per day orally, and their blood samples were taken prior to and at days 1, 3, 5, and 7 days post-administration of cimetidine. Leukocyte counts and differentials were obtained by the conventional hemogram, and the leukocyte subsets were analyzed by flow cytometry. Cimetidine administration caused leukocytosis, dependent on the increase of neutrophils, as well as of the CD3-positive T lymphocytes, and the subset of CD4-positive cells among them. On the other hand, the NK cell subpopulation was decreased, and the NKT cell subpopulation was not affected. The present results suggest that cimetidine is a modulator of the cellular immunity, and may be used as the activator of the tumor specific immunoresponse.     

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.     

光动力对小鼠鼻咽癌移植瘤survivin表达及CD+8细胞毒性T细胞的影响

目的 观察氨基酮戊酸(5-Aminolevulinic acid,ALA)介导的光动力疗法(photodynamic therapy,PDT)对小鼠鼻咽癌移植瘤survivin蛋白表达及CD+8细胞毒性T细胞(CD+8 CTLs)的影响.探讨ALA-PDT治疗鼻咽癌的机制.方法 32只 SPF级BALB/c 小鼠皮下接种鼻咽癌CNE 2细胞建立荷瘤鼠模型,随机分为2组:PDT组、对照组.PDT治疗后定期采用免疫组化法检测肿瘤组织survivin蛋白表达及CD+8细胞毒性T细胞.结果 治疗后24h,PDT组survivin蛋白表达明显低于对照组(P＜0.05),肿瘤局部CD+8细胞数量较对照组无明显变化(P＞0.05).治疗后72h,PDT组肿瘤局部CD+8细胞数量均明显高于对照组(P＜0.05).结论 抑制survivin蛋白的表达以及产生局部免疫效应均可能是ALA-PDT治疗鼻咽癌的机制之一.     

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。     

An increase in CD4+CD25+FOXP3+ regulatory T cells in tumor-infiltrating lymphocytes of human glioblastoma multiforme

The subpopulation of CD4+CD25+ immunoregulatory T (Tr) cells constitutes 5%-10% of CD4+ cells in humans. These cells play a crucial role in the control of tumor immune response. In this study, we evaluated the distribution of Tr cells in tumor-infiltrating lymphocytes of human glioblastoma multiforme and examined the difference between the brain and autologous blood with respect to Tr cells. Glioma samples from 10 patients were classified as WHO grade IV astrocytoma. Control samples were obtained from patients undergoing resection of a seizure focus. The samples were analyzed by flow cytometry to determine the frequency of Tr cells and by real-time PCR for forkhead box P3 (FOXP3) expression. We then examined the expression of CD62L, CD45RO, and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and assessed the functionality of Tr cells in vitro. There was a significant difference in the number of FOXP3-expressing CD4+CD25+ T cells within glioma-infiltrating lymphocytes as compared to controls (P < 0.01). This difference was further observed in studies of autologous patient blood and control blood. The expression level of FOXP3 mRNA was high in Tr cells and weak in CD4+CD25-T cells. Moreover, the expression of CD62L and CTLA-4 was elevated in glioma Tr cells as compared to that in the controls. These cells were also CD45RO positive. Functional assays confirmed the suppressive activity of Tr cells in patients with glioma. The expression of CD4+CD25+FOXP3+ T cells was significantly higher in patients with glioblastoma multiforme than in controls. This increase in the frequency of Tr cells that display suppressive activity might play a role in modulation of the immune response against glioma. In light of these findings, Tr cells may represent a potential target for immunotherapy of malignant brain tumors.     

康莱特对晚期乳腺癌患者外周血CD4及PD-1阳性T细胞的影响

目的：检测康莱特（KLT）对晚期乳腺癌患者外周血CD4+及程序性死亡分子1（PD-1）阳性T细胞比例的影响,探讨KLT在乳腺癌患者中诱导抗肿瘤免疫的作用。方法选取接受过化疗或内分泌治疗后肿瘤进展的晚期乳腺癌患者30例,以KLT注射液处理;处理前后取外周血经流式细胞术检测治疗前后外周血中CD4+和CD4+PD-1+T淋巴细胞数量变化。并选取同期健康体检者20名为对照组,常规抽血检测。结果晚期乳腺癌患者治疗前外周血CD4+T细胞较健康人群低,而CD4+PD-1+T细胞的比例较健康人群高;经KLT治疗后的晚期乳腺癌患者外周血CD4+T细胞较治疗前显著增高,而CD4+PD-1+T细胞的比例较治疗前显著降低,差异均有统计学意义（P﹤0.05）。结论 KLT有效降低晚期乳腺癌患者外周血CD4+PD-1+T淋巴细胞比例,减弱机体肿瘤免疫抑制状态。     

结直肠癌及腺瘤患者CD4+、CD8+和CD28+T淋巴细胞的亚群变化及临床意义

背景与目的：结直肠癌（colorectal cancer,CRC）严重影响患者生存。探讨肿瘤微环境（tumor microenvironment,TME）T细胞亚群在CRC和腺瘤中的表达及意义。方法：用免疫组织化学法和流式细胞术对51例健康人（对照组）、46例结直肠腺瘤（腺瘤组）、100例CRC（癌症组）和15例CRC术后（癌术后组）患者进行T细胞亚群检测。结果：① 对照组、腺瘤组及癌症组3组中CD4⁺T细胞的阳性率分别是90.00%、43.75%及32.65%,CD8⁺T淋巴细胞的阳性率分别是30.00%、56.25%及75.51%,CD28⁺T淋巴细胞的阳性率分别是42.86%、30.00%及20.00%。② 对照组、腺瘤组及癌症组3组中CD4⁺、CD4⁺/CD8⁺、CD28⁺、CD8⁺CD28⁺和CD8^－CD28⁺逐渐降低,CD8⁺、CD8⁺CD28^－逐渐增加（P＜0.05）;癌术前术后T细胞亚群差异有统计学意义（P＜0.05）。结论：① CRC微环境T细胞亚群中CD4⁺、CD4⁺/CD8⁺、CD28⁺、CD8⁺CD28⁺和CD8^－CD28⁺呈递减趋势,CD8⁺、CD8⁺CD28^－呈递增趋势,且在癌前病变腺瘤中已逐步出现上述趋势变化。② CRC患者行肿瘤切除术后,其T细胞亚群有所恢复,故在一定程度上,CRC中T细胞亚群的变化可以早期预测结直肠疾病的发展。     

Correlated ultrastructural and immunological findings in CD8+ and CD4+ peripheral T-cell lymphomas

Ultrastructural features of CD8+ and CD4+ peripheral T-cell lymphomas were studied and the results revealed distinct traits correlated with phenotype. CD8+ peripheral T-cell lymphomas were characterized by a rich organular pattern with a well-developed Golgi apparatus, dense granules, numerous and atypical giant mitochondria. CD4+ peripheral T-cell lymphomas were characterized by wide cytoplasmic areas devoid of organelles. Since similar ultrastructural features differentiated normal and pathological CD8+ and CD4+ peripheral T-lymphocytes, we conclude that under both normal and pathological conditions the expression on the part of the peripheral T-lymphocytes of CD8+ and CD4+ phenotypes is associated to morphological features which distinguish the two subsets.     

CD4+/CD8+ T淋巴细胞在肝细胞癌组织中的浸润及与预后的相关性研究

目的 检测CD4⁺/CD8⁺ T淋巴细胞在肝细胞癌（hepatocellular carcinoma,HCC）组织中的浸润程度,并分析其与预后的相关性。方法 收集行肝切除术的HCC患者215例,采用免疫组化技术检测CD4⁺/CD8⁺ T淋巴细胞在HCC癌组织中的浸润程度,根据浸润情况比较患者肝切除术后无瘤生存率和总生存率。结果 CD4⁺ T淋巴细胞高浸润和低浸润比例分别为60.9%和39.1%。CD4⁺ T淋巴细胞高浸润组患者总生存率和无瘤生存率均显著高于低浸润组（P=0.015,P=0.038）。CD8⁺ T淋巴细胞高浸润和低浸润比例分别为34.9%和65.1%。CD8⁺ T淋巴细胞高浸润组患者的总生存率和无瘤生存率亦显著高于低浸润组患者（P=0.033,P=0.047）。结论 CD4⁺或CD8⁺ T淋巴细胞低浸润可能与HCC患者术后不良预后相关。     

肿瘤患者CD4+CD25+调节性T细胞流式细胞术分析

目的:分析比较肿瘤患者和健康人外周血CD4+CD25+调节性T细胞的特点,为肿瘤免疫学研究及治疗探索新方法.方法:收集并分离30例肿瘤患者和32例健康人的外周血单个核细胞(PBMCs),用荧光标记的抗人CD4及抗人CD25单抗标记肿瘤患者和健康人PBMCs细胞,FCM检测CD4+CD25+Treg细胞,分析CD4+CD25+Treg细胞在肿瘤患者和健康人中的差别.结果:肿瘤患者的CD4+CD25+Treg细胞百分数明显高于健康人(年龄<55者62.4 vs 40.4;年龄≥55者53.1 vs 31.0,P<0.05).结论:肿瘤患者的CD4+CD25+Treg细胞高于健康对照,为肿瘤免疫治疗提供新策略,通过删除CD4+CD25+Treg细胞,有可能增强抗瘤免疫反应.     

CD4+ T-cell help in the tumor milieu is required for recruitment and cytolytic function of CD8+ T lymphocytes

CD4 help for CD8(+) T lymphocytes prevents tolerance and promotes the survival of effector and memory CD8(+) T cells. Here, we describe additional helper functions that require CD4(+) T cells within the tumor environment. CD8(+) T-cell recruitment, proliferation, and effector function within the tumor were greatly enhanced by tumor-specific CD4(+) T cells. Recruitment of CD8(+) T cells was accelerated by IFN-γ-dependent production of chemokines. Production of interleukin-2 by tumor resident CD4(+) T cells enhanced CD8(+) T-cell proliferation and upregulated expression of granzyme B. These results highlight a novel role for tumor-specific CD4(+) T cells in promoting CD8(+) T-cell recruitment and cytolytic function, two previously unappreciated aspects of tumor-specific CD4 help.     

Amphiregulin activates regulatory T lymphocytes and suppresses CD8+ T cell-mediated anti-tumor response in hepatocellular carcinoma cells

CD8⁺ T cell-mediated immune response plays an important role in inhibiting progression of hepatocellular carcinoma (HCC). For strategic immunotherapy, it is critical to understand why some of the tumor cells escape from this immune attack. In this study, we investigated how HCC cells alter endogenous anti-tumor immunity and their related signaling pathways. We found that HCC cells, both in vitro and in vivo, substantially secret and express amphiregulin (AR). AR in turn activates immunosuppressive function of intratumoral CD4⁺Foxp3⁺ regulatory T cells (Tregs), a major inhibitor of CD8⁺ T cells. Using either lentiviral siRNA, or AR neutralizing antibody, we blocked the expression and function of AR to test the specificity of AR mediated activation of Tregs, Biochemical and cell biology studies were followed and confirmed that blocking of AR inhibited Tregs activation. In addition, we found that AR can trigger the activation of rapamycin complex 1(mTORC1) signaling in Tregs. The mTORC1 inhibitor rapamycin treatment led to compromise Treg function and resulted in enhancing anti-tumor function of CD8⁺ T cells. Blocking AR/EGFR signaling in Tregs with Gefitinib also enhanced anti-tumor immunity and decreased tumor size in a mouse xenograft tumor model. Taken together, our study suggested a novel mechanism of functional interaction between HCC and Tregs for regulating anti-tumor function of CD8⁺ T cells.     

HepA-H和HepA-L肝癌荷瘤小鼠CD8+/CD28+T细胞和肿瘤新生淋巴管的研究

目的研究不同淋巴转移潜能肝癌（HepA-H和HepA-L）荷瘤小鼠体内CD8^＋／CD28^＋T淋巴细胞和肿瘤新生淋巴管，探讨与肿瘤淋巴转移的关系。方法用两种来源相同，而淋巴转移能力不同的小鼠肝癌细胞亚系，HepA-H（高淋巴转移）和HepA-L（低淋巴转移），小鼠皮下接种，制备荷瘤动物模型。采用抗小鼠CD8、CD28荧光标记单克隆抗体，流式细胞术定量检测小鼠外周血和肿瘤组织内CD8^＋／CD28^＋T淋巴细胞数量；应用5＇-核苷酸酶-碱性磷酸酶双重组化染色法，观察肿瘤新生淋巴管。结果肿瘤皮下接种后14天，HepA-H组荷瘤小鼠外周血CD8^＋／CD28^＋T淋巴细胞数量明显低于正常对照组（P〈0．05）HepA-H组肿瘤组织内CD8^＋／CD28^＋T淋巴细胞数量显著低于HepA-L组（P〈0．05）。两种肿瘤细胞亚系均可诱导肿瘤新生淋巴管，但HepA-H肿瘤内和瘤周最高淋巴管密度均明显高于HepA-L组（P〈0．01）。结论肿瘤淋巴转移能力的差异与体内CD8^＋／CD28^＋T淋巴细胞数量及肿瘤新新生淋巴管有关。