以CpG-ODN为佐剂的MAGE-n蛋白疫苗的免疫学作用及抗肿瘤效应

Immune responses and anti-tumor effects of melanoma antigen-n protein vaccine accompanied by CpG-containing oligodeoxynucleotide adjuvant

目的制备人黑色素瘤抗原-n(MAGE-n)蛋白疫苗,研究含CpG基序的寡聚脱氧核苷酸(CpG-ODN)联合MAGE-n蛋白疫苗,诱导小鼠产生的免疫应答,及在肿瘤免疫治疗中的作用。方法对含有MAGE-n原核表达质粒pGEX-MAGE-n的大肠杆菌DH5α进行诱导表达和分离纯化,作为MAGE-n蛋白疫苗,人工合成CpG-ODN作为佐剂,以C57BL/6小鼠为实验动物进行免疫接种;采用ELISPOT、LDH释放试验、血清ELISA法检测小鼠的细胞免疫和体液免疫反应;通过观察瘤体积和生存期了解疫苗的抗肿瘤效果。结果联合应用CpG-ODN和纯化的MAGE-n蛋白,能诱发C57BL/6小鼠产生较强的MAGE-n特异性的细胞和体液免疫应答;在MAGE-n阳性的B16肿瘤的免疫治疗中,可以减缓肿瘤的生长速度,延长荷瘤鼠的生存期。结论以CpG-ODN作为佐剂的MAGE-n蛋白疫苗,可以诱导C57BL/6小鼠产生MAGE-n特异性的免疫应答,对荷瘤鼠有较好的抗肿瘤效果,为肿瘤免疫治疗提供了一条新的途径。

Objective To prepare melanoma antigen n（MAGE-n）protein vaccine and to investigate the immune responses and antitumor effects of MAGE-n protein vaccine accompanied by CpG-containing oligodeoxynucleotide （CpG-ODN） adjuvant. Methods The DH5α containing the MAGE-n prokaryotic expression plasmid pGEX-MAGE-n was induced and the protein was purified as protein vaccine. The CpG-ODN was synthesized as adjuvant and the C57BL/6 mice were inoculated. The cellular and humoral immune responses were detected by ELISPOT, cytotoxicity assay and enzyme linked immunosorbent assay （ELISA）. The antitumor effects were detected through tumor volume and life span. Results The MAGE-n protein accompanied by CpG-ODN could induce strong MAGE-n-specific cellular and humoral immune responses. In the MAGE-n positive B16 tumor model of C57BL/6, the growth velocity of tumor was decreased and the life span was prolonged with the treatment of vaccine. Conclusion MAGE-n protein vaccine accompanied by CpG-ODN adjuvant can induce strong immune responses and anti-tumor effects against MAGE-n positive B16 tumor, which provides a new way for tumor therapy.