人乳头状瘤病毒16型不同基因疫苗联合免疫的实验研究

The experimental study of HPV16 vaccines in prime-boost strategy

目的探索联合免疫策略在预防和治疗人乳头状瘤病毒16型(HPV16)相关肿瘤中的作用。方法在C57BL／6动物模型中,观察了表达HPV16基因的融合蛋白L2E7疫苗和重组痘苗病毒mE67疫苗的不同联合免疫方式在预防和治疗HPV16相关肿瘤中的作用。用酶联免疫斑点(ELISPOT)和细胞毒T淋巴细胞(CTL)反应评价它们在诱发机体产生细胞免疫应答中的作用。结果我们发现以HPV16 L2E7融合蛋白+佐剂(CpG)初免,用重组痘苗病毒rVVmE67加强免疫的联合免疫方式在C57BL/6小鼠实验中可以有效预防和治疗HPV16相关肿瘤的攻击。ELISPOT可以检测到高水平的E749-57肽特异性,分泌IFN-γ的效应T细胞。CTL检测同样反应出这种联合免疫方式所诱发的CTL细胞可以有效识别并杀伤含HPV16 E6／E7的靶细胞。结论以HPV16 12E7融合蛋白+CpG初免,用重组痘苗病毒rVVmE67加强的联合免疫策略可以有效防治HPV16相关肿瘤,为进一步研究提供了科学基础。

Objective To study the effecfion of heterologous prime-boost strategies in prevention and treatment of human papillomavirus（HPV） associated tumors. Methods To observe the prime-boost strategy effectiveness using recombinant HPV16 L2E7 fusion protein with the CpG adjuvant and a recombinant vaccinia-based vaccine expressing HPV16 E6 and E7 in a prophylactic and therapeutic mouse model. The cell-mediated immunity induced by different kinds of prime-boost strategies was assessed by HPV16 E749-57 peptide-speeific, IFN-γ enzymelinked immunospot （ELISPOT） and cytotoxic T lymphocyte （CTL） assay. Results When priming with the recombinant HPV16 L2E7 fusion protein/adjuvant followed by boosting with the recombinant vaccinia-based vaccine, we found that this kind of immunization strategy protected C57BIJ6 mice against the challenge of HPV16-positive tumor cells both in prophylactic and in therapeutic settings. The strongest E749-57 peptide-specific, IFN-7 secreting effector T cell response can be generated by this kind of prime-boost strategy. We also found that cytotoxic T lymphocyte induced by this kind immunization can recognize and kill the target cells. Conclusion The heterolngous prime-boost regimen is highly effective in terms of prophylactic and therapeutic approaches.