MAGE-3抗原肽体外诱导肝癌患者免疫应答的研究

目的：利用载有MAGE－3抗原肽的树突状细胞（DC）活化原发性肝细胞癌（HCC）患者T淋巴细胞，探讨是否可以体外诱导特异性细胞毒T细胞细胞（CTL）应答。方法：通过逆转录多聚酶链反应和测序分析MAGE－3多肽表位密集区的核苷酸变异状况，体外培养HLA－A2表型的HCC患者及正常献血员外周血来源DC，并经孵育携带MAGE－3／HLA－A2抗原肽FLWG－PRALV，用以活化T淋巴细胞，利用特异性杀伤实验检测CTL应答。结果：中国HCC患者表达的MAGE－3序列高度保守。用特定细胞因子和无血清培养基可成功培养HCC患者外周血精源的DC。经多肽冲击的DC诱导，3例HCC例者和3例正常献血员可成功培养HCC患者外周血来源的DC。经多肽冲击的DC诱导，3例HCC患者的3例正常献血员中各有2例产生CTL免疫应答。结论：载有MAGE－3抗原肽的DC可以体外诱导特异性的CTL免疫应答。提示HLA－A2限制性的MAGE－3抗原肽经DC递呈可以作为有潜力的肝癌免疫治疗疫苗。

Peptide derived from MAGE-3 epitope induced cytotoxic T lymphocytes of hepatocellular carcinoma patient in vitro

Objective To investigate whether the cytotoxic T lymphocytes (CTLs) response can be induced by MAGE-3-loaded dendritic cells in vitro activating the T lymphocytes in hepatocellular carcinoma patients.Methods The encoding nucleotides of MAGE-3 epitopes were analyzed by RT-PCR assay,cloning and sequencing.Dendritic cells (DCs) were induced from peripheral blood mononuclear cells of 3 HCC patients and 3 healthy donors with HLA-A2 phenotypes,and cultured with GM-SCF and IL-4 in AIM-V medium.The expanded DCs were pulsed by MAGE3/HLA-A2 peptide (FLWGPRALV) and exposed to the radiation with a dose of 3?000 rads.Irradiated DCs were used to stimulate autologous T lymphocytes for three times.Then the induced CTLs were evaluated by killing peptide-pulsed T2 cells.Results Compared with the sequences in Genbank,the MAGE-3 coding genes isolated from Chinese patients were highly conserved.The MAGE-3 peptide-loaded DCs can induce specific CTLs successfully in 2 of 3 HCC patients and 2 of 3 healthy donors.Conclusion MAGE-3 peptide-loaded DCs can activate T lymphocytes and induce peptide-specific CTL response,and is a potential target for specific immunotherapy for HCC.