光动力对小鼠鼻咽癌移植瘤survivin表达及CD8＋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CD8＋细胞毒性T细胞（CD8＋ 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CNE2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CD8＋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CD8＋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CD8＋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。     

光动力对人子宫颈癌Hela细胞的杀伤作用及光动力剂量的研究

目的 观察氨基酮戊酸(5-Aminolevulinic acid,ALA)介导的光动力疗法(photodynamic therapy,PDT)对人子宫颈癌Hela细胞株的杀伤效应,探讨最佳光动力剂量.方法 实验分为空白对照组、单纯激光组、单纯光敏剂组和实验组(照光+光敏剂).对体外培养的人子宫颈癌Hela细胞株进行光动力实验,应用MTT法检测其光密度值(OD570),观察不同光动力剂量下对人子宫颈癌Hela细胞在体外的抑制作用,并绘制其抑制曲线和观察其形态学变化.结果 实验组于治疗后明显抑制体外培养的人子宫颈癌Hela细胞,而空白对照组、单纯使用光敏剂组及单纯激光照射组对细胞增殖均无明显影响.光动力治疗后12 h,镜下细胞变形,细胞内出现大量的核碎裂、核融解、核消失等坏死征象,少部分表现为凋亡.结论 ALA介导的光动力疗法(ALA-PDT)可明显抑制体外培养的人子宫颈癌Hela细胞株的生长,ALA浓度为 0.5 mmol/L、激光剂量为5J/cm2是杀伤Hela 细胞的最佳剂量.     

鼻咽癌组织与外周血CD4+CD25+调节性T细胞检测及临床意义

目的 通过检测鼻咽癌患者肿瘤组织及外周血中CD4+T、CD8+T、CD4+CD25T、CD4+CD25+T细胞的频数,寻找客观、全面评价鼻咽癌患者免疫状态的临床指标.方法 采用流式细胞术检测40例初诊鼻咽癌患者及10例正常时照鼻咽部组织和外周血CD4+T、CD8+T、CD4+CD25-T、CD4+CD25+T细胞比例.结果 鼻咽癌患者CD4+T细胞比例及CD4+/CD8+T比值均低于对照组(P<0.05),而CD8+T细胞两组间差异无统计学意义(P>0.05),但是CD4+/CD8+T比值在鼻咽癌组织与外周血间差异无统计学意义(P>0.05).鼻咽癌组织及外周血中CD4+CD25+T细胞比例都高于对照组(P<0.05),同时癌组织中该细胞比例远远高于外周血(P<0.05).在鼻咽癌组织中CD4+CD25+T细胞与CD8+T细胞、CD4+CDQ5-T细胞呈负相关(r分别为-0.70、-0.675,P<0.05),而在外周血中没有相关关系(P>0.05).在不同T(原发肿瘤大小)组间,T4组的鼻咽癌组织中CD4+CD25+T细胞分别高于T1、T2、T3各组(P<0.05).而在T1、T2、T3各组间差异无统计学意义(P>0.05);鼻咽癌中CD4+CD25+T细胞比例与患者有无淋巴结转移并无关系(P>0.05);鼻咽癌组织中Ⅲ+Ⅳ期组CD4+CD25+T细胞比例高于Ⅰ+Ⅱ期组(P<0.05),而在外周血中两组间差异无统计学意义(P>0.05).结论 CD4+CD25+T细胞与鼻咽癌病程进展无相关性,但是联合检测患者肿瘤组织及外周血中CD4+CD25+T细胞的频数并结合既往CD4+/CD8+T比值会全面反应患者免疫状态,为临床治疗提供依据.     

ALA—光动力疗法的作用机理及应用

ＡＬＡ－ＰＤＴ是近年来兴起的一门新型治疗技术，疗效可靠，简便，毒副作用小。本文综述了近５年来的研究状况，尤其对其治疗机理和应用范围等方面加以介绍。     

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。     

EBV阳性鼻咽癌相关性中性粒细胞抑制肿瘤微环境中的CD8+ T细胞活化

目的：分析鼻咽癌（NPC）肿瘤微环境（TME）中的肿瘤相关中性粒细胞（TAN）浸润与患者的预后和临床病理特征之间的相关性,初步探讨EBV阳性NPC的TAN对CD8+ T细胞活化的作用。方法：收集2008年至2012年间中山大学肿瘤防治中心收治的118例初治且无转移的EBV阳性NPC患者的肿瘤组织标本,通过免疫组织化学染色法观察并分析NPC组织中CD8+T细胞、TAN浸润和EBV感染之间的关系,检测NPC组织标本中的TAN浸润程度并分析其与患者预后和临床病理特征之间的关系;流式细胞术检测HK1-EBV细胞培养上清液对TAN极化的N2型标志物（CD182和CD206）表达水平的影响,并进一步检测极化后的TAN对CD8+ T细胞活化标志物（CD69和PD-1）表达水平的影响。结果：EBV阳性NPC组织中CD8+T细胞和TAN浸润增多且两者在数量上呈负相关关系（P=0.005 2）;EBV阳性NPC组织中高水平浸润的TAN与患者的不良预后密切相关（OS：P=0.025,PFS：P=0.027）,TAN浸润水平是EBV阳性NPC患者总生存时间（P=0.035）的独立预后因子;与对照组相比,HK1-EBV细胞培养上清液可诱导TAN极化并高表达N2型标志物（CD182：P<0.001;CD206：P<0.01）;极化后的TAN可抑制CD8+T细胞CD69的表达并促进PD-1的表达（P<0.001）。结 论：EBV阳性NPC能够促进TME中的TAN浸润增多并使其极化成N2型,从而抑制CD8+ T细胞的活化,发挥免疫抑制作用,与NPC患者的不良预后密切相关。     

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。     

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。     

胆固醇代谢调控CD8+T细胞抗肿瘤作用的研究进展

CD8+T细胞又名细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL),具有直接杀死病原体感染细胞和癌细胞的作用.然而,CD8+T细胞常常丧失其效应功能,继而限制肿瘤微环境中的抗肿瘤免疫,因此,如何重新激活CD8+T细胞的抗肿瘤效力是目前需要解决的问题.最近研究发现,胆固醇代谢在肿瘤中发挥重要作用...     

CD103+CD8+T细胞在结直肠癌组织中的浸润分布及其临床意义

[摘要] 目的:研究组织驻留CD8+T细胞（CD103+CD8+T细胞）在结直肠癌（colorectal cancer,CRC）组织中浸润程度及分布特征,分析其浸润程度与患者临床病理特征及预后的关系。方法:选用上海芯超生物科技有限公司的88 例结肠癌HColA180Su14和77 例直肠癌HRec-Ade180Sur-03 组织芯片,应用免疫荧光染色法分别检测CRC组织及相应癌旁组织中CD103+CD8+T细胞的浸润分布特征及程度,Wilcoxon 秩和检验比较CRC及癌旁组织中CD103+CD8+T细胞浸润程度,χ2检验分析CRC中CD103+CD8+T细胞浸润程度与患者临床病理特征的关系;Kaplan-Meier 生存分析CD103+CD8+T细胞浸润程度与患者预后的关系,拟合Cox 模型评价不同指标与患者预后的关系。结果: CRC组织中CD103+CD8+T 细胞浸润程度与癌旁组织比较差异无统计学意义（P>0.05）,有远处转移患者中CD103+CD8+T细胞高度浸润的比率显著低于无远处转移患者（P<0.01）,CD103+CD8+T细胞浸润程度与患者其他临床病理特征无明显相关（P>0.05）。Kaplan-Meier生存分析显示,CD103+CD8+T细胞高度浸润患者的OS较低度浸润患者显著延长（54.42% vs 25.00%,P<0.05）,多因素Cox 显示,病理分级（P<0.01）和CD103+CD8+T细胞高度浸润（P<0.05）均可作为CRC患者预后的独立影响因素。结论: CRC组织中CD103+CD8+T细胞浸润与预后相关,提示其在CRC发生发展过程中发挥重要作用。     

Cell therapy of stage IV nasopharyngeal carcinoma with autologous Epstein-Barr virus-targeted cytotoxic T lymphocytes.

PURPOSE: Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV)-related malignancy expressing EBV antigens that are possible targets of cell therapy, including latent membrane protein 2 (LMP2). We conducted a clinical trial of EBV-targeted cell therapy with autologous virus-specific cytotoxic T lymphocytes (CTLs) for NPC refractory to conventional treatments. PATIENTS AND METHODS: Ten patients with EBV-related stage IV NPC in progression after conventional radiotherapy and chemotherapy received intravenously autologous EBV-specific CTLs reactivated and expanded ex vivo from peripheral blood lymphocytes through stimulation with EBV-transformed autologous B-lymphoblastoid cell lines (LCL). Toxicity, specific cellular immune responses, and clinical tumor responses were evaluated. RESULTS: EBV-specific CTLs could be generated in all patients and were predominantly CD3+/CD8+ T lymphocytes displaying specific killing of autologous EBV-LCL, autologous NPC cells as well as autologous targets bearing the EBV antigen LMP2. Patients received two to 23 infusions of EBV-specific CTLs that were well tolerated with the exception of grade 1 to 2 inflammatory reactions at the tumor site in two cases. Control of disease progression was obtained in six of 10 patients (two with partial response and four with stable disease). Analysis of interferon-gamma-producing cells demonstrated an increased frequency of EBV-specific immunity, with appearance of LMP2-specific responses in four patients, of whom three had clinical benefit. CONCLUSION: Cell therapy with EBV-targeted autologous CTLs is safe, induces LMP-2-specific immunologic responses, and is associated with objective responses and control of disease progression in patients with stage IV NPC resistant to conventional treatments.     

Nutrition deprivation affects the cytotoxic effect of CD8 T cells in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and the third leading cause of cancer-related death worldwide. Factors including carcinogens, infection of hepatitis viruses, alcohol abuse, and metabolic disorders such as non-alcoholic fatty liver disease mainly contribute to HCC initiation and progression. Immunotherapy is one of the most powerful tools for unresectable HCC treatment in patients. CD8⁺ T cells are a major immune component in the tumor microenvironment with cytotoxic effects against cancer cells. However, these CD8⁺ T cells commonly display an exhaustion phenotype with high expression of programmed cell death protein 1, T-cell immunoglobulin and mucin-domain containing-3, and/or lymphocyte-activation gene 3, producing low levels of perforin (PRF1) and granzyme B (GZMB), as well as anti-tumor cytokines, such as interferon gamma and tumor necrosis factor alpha. In the referenced study, the authors also showed that deprivation of glutamine decreased the antitumor function of CD8⁺ T cells, as well as the production of PRF1 and GZMB. However, the role of each amino acid in T cell function and exhaustion may depend on tumor type and tumor microenvironment, including the source of other nutrients. Overall, amino acids or other nutrient metabolites in the tumor microenvironment play a pivotal role in both tumor growth and immune response.     

Generation and purification of CD8+ melan-A-specific cytotoxic T lymphocytes for adoptive transfer in tumor immunotherapy.

Tumor antigens that might serve as potential targets for adoptive T-cell therapy have been defined in different tumor entities, especially in malignant melanoma. To generate conditions to induce primary T-cell responses against different HLA-A*0201-restricted melanoma peptides and to allow further expansion of peptide-specific T cells for adoptive transfer, CD8+-purified T cells from healthy donors were stimulated with Melan-A-pulsed autologous dendritic cells. Dendritic cells were generated in vitro from monocytes with granulocyte macrophage colony-stimulating factor, interleukin-4, and transforming growth factor-beta1. After 3-4 weekly stimulation cycles with Melan-A-pulsed DCs, we were able to induce a strong peptide-specific CTL response in vitro. MHC-peptide tetramer staining revealed a frequency of up to 3.5% CD8+/Melan-A+ T cells. Additional antigen-independent expansion with anti-CD3/anti-CD28 monoclonal antibodies together with interleukin-2 gave rise to 600-fold expansion of CD8+ CTLs that maintained Melan-A specificity and were able to efficiently lyse Melan-A-expressing melanoma cells. To enrich antigen-specific T cells in vitro, we used a recently established technology for analysis and sorting of live cells according to secreted cytokines. In the present study, we demonstrated that Melan-A-specific T cells can be purified by magnetic separation according to secreted IFN-gamma. These cells revealed a very potent monospecific CTL response, even at low E:T ratios, against Melan-A-pulsed and Melan-A-expressing target cells. Altogether, our study demonstrated that we have developed an efficient method for generating large numbers of peptide-specific T cells in vitro that may be used for adoptive T-cell transfer in tumor immunotherapy.     

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。     

The apoptosis inhibitor protein survivin induces tumor-specific CD8+ and CD4+ T cells in colorectal cancer patients

The identification of tumor-associated antigens expressed by colorectal carcinoma remains one of the major goals for designing novel immunological treatments for this tumor. By using a reverse-immunology approach, we show here that the inhibitor of apoptosis protein, survivin, is immunogenic in colorectal cancer patients. In particular, we found that survivin elicited CD8(+) T cell-mediated responses in peripheral blood or in tumor-associated lymphocytes from patients at different disease stage. Colorectal carcinoma cells were recognized by survivin-specific T lymphocytes, and the survivin-specific, class-I HLA-restricted T lymphocytes were fully activated and released interleukin-2 in response to HLA/survivin-peptide complexes expressed by tumor cells. In addition to CD8-mediated responses, survivin specifically stimulated CD4+ T-cell reactivity in peripheral blood lymphocytes from the same patients, thus suggesting that a complete activation of the immune system may occur in response to this antiapoptotic protein. These findings indicate that survivin could be considered a valuable tumor-associated antigen for immune-based clinical approaches in colorectal cancer.     

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.     

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.     

CD8+ T cell-mediated control of distant tumours following local photodynamic therapy is independent of CD4+ T cells and dependent on natural killer cells

Cancer survival rates decrease in the presence of disseminated disease. However, there are few therapies that are effective at eliminating the primary tumour while providing control of distant stage disease. Photodynamic therapy (PDT) is an FDA-approved modality that rapidly eliminates local tumours, resulting in cure of early disease and palliation of advanced disease. Numerous pre-clinical studies have shown that local PDT treatment of tumours enhances anti-tumour immunity. We hypothesised that enhancement of a systemic anti-tumour immune response might control the growth of tumours present outside the treatment field. To test this hypothesis we delivered PDT to subcutaneous (s.c.) tumours of mice bearing both s.c. and lung tumours and monitored the growth of the untreated lung tumours. Our results demonstrate that PDT of murine tumours provided durable inhibition of the growth of untreated lung tumours. The inhibition of the growth of tumours outside the treatment field was tumour-specific and dependent on the presence of CD8(+) T cells. This inhibition was accompanied by an increase in splenic anti-tumour cytolytic activity and by an increase in CD8(+) T cell infiltration into untreated tumours. Local PDT treatment led to enhanced anti-tumour immune memory that was evident 40 days after tumour treatment and was independent of CD4(+) T cells. CD8(+) T cell control of the growth of lung tumours present outside the treatment field following PDT was dependent upon the presence of natural killer (NK) cells. These results suggest that local PDT treatment of tumours lead to induction of an anti-tumour immune response capable of controlling the growth of tumours outside the treatment field and indicate that this modality has potential in the treatment of distant stage disease.     

MAGE-specific cytotoxic T lymphocytes require non-specific CD54 adherence receptors on carcinoma cells

We investigated several factors that could regulate the susceptibility of carcinoma cells to MAGE-2-specific CTL mediated lysis. Cytofluorometric analysis showed that the cytolysis correlated with the expression of CD54. IFN-gamma treatment induced the TAP-1 and LMP-2 genes, continuously up-regulated the HLA class I expression and increased cytolysis. Although HLA class I were highly induced in MRKnu1 cells, CD54 was not induced and the cytolysis was minimal. Cytotolysis of IFN-gamma-treated MKN-1 cells was completely inhibited by a monoclonal anti-CD54 antibody. These results suggest that HLA-restricted CTL lysis requires non-specific CD54 adherence receptors in addition to specific TCR signals.