树突状细胞负载MAGE-n表位肽的体外免疫学效应研究

Study on immunoreaction induced by DCs loaded with MAGE-n antigen peptide in vitro

目的:研究树突状细胞(dendritic cell,DC)负载MAGE-n表位肽QLVFGIEVV体外诱导特异性CTL的能力及其抗肿瘤效应。方法:MAGE-n表位肽以固相多肽合成技术合成,并用HPLC进行纯化,质谱法(MS)鉴定,以流式细胞仪筛选HLA-A2+人外周血PBMC,连续贴壁法分离培养人外周血来源树突状细胞,用成熟的DC负载MAGE-n表位肽QLVFGIEVV反复刺激活化诱导抗原特异性CTL,用51Cr释放法检测CTL的杀伤活性,并用抗HLA-A2分子单抗进行杀伤抑制实验。结果:用DC负载MAGE-n表位肽QLVF-GIEVV可诱导特异性CTL反应,对MAGE-n阳性表达细胞有较强的杀伤作用。结论:DC负载抗原肽QLVF-GIEVV在体外可诱发较强的特异性免疫反应。

Objective：To investigate the potency and antitumor effect of specific cytotoxic T lymphocytes induced by hepatocarcinoma antigen peptide QLVFGIEVV-loaded dendritic cells（DCs）.Methods： The MAGE-n candidate HLA-A2 restricted CTL epitopes were synthesized with solid phase strategies,purified with reverse phase HPLC and identified with mass spectrometry.The peripheral blood mononuclear cells（PBMC） of HLA-A2 positive healthy donors were selected by multiple stimulations.Utilizing successive adherence method to obtain the mature DC cells,peptide-specific CTLs were induced with peptide-pulsed dendritic cells.The specific CTL reaction and inhibitory effect of anti-HLA-A2 mAb on CTL cytotoxicity were detected in vitro by 51Cr-release assay.Results： Spleen T lymphocytes could be induced to proliferate and differentiate into specific CTLs by DCs loaded with the peptide.Antibody-blocking test demonstrated that the cytotoxity of CTLs was strictly limited by HLA-I molecule.Conclusion： QLVFGIEVV-loaded DCs can induce efficient and specific antitumor immune reaction in vitro.