摘要目的 建立三色混合荧光HPV假病毒中和检测系统,并评价其在检测HPV九价疫苗免疫血清免疫原性的应用.方法 分别选取红色、绿色和蓝色荧光蛋白的质粒N31-MCHREEY、N31-EGFP和N31-mTagBFP构建HPV6/11/16/18/31/33/45/52/58假病毒,利用双抗夹心法和病毒半数组织培养感染剂量法检测HPV假病毒浓度和感染滴度;利用单色荧光与三色混合荧光HPV16/33/45假病毒,检测HPV九价疫苗免疫小鼠血清的中和滴度,以验证三色混合荧光HPV假病毒系统的准确性;采用单色荧光和三色混合荧光HPV6/11/16/18/31/33/45/52/58假病毒系统检测HPV九价疫苗免疫食蟹猴血清的中和滴度,判断其是否可应用于HPV九价疫苗免疫血清的免疫原性检测.结果 含有绿色、红色和蓝色荧光质粒的HPV16型假病毒的浓度为5～6μg/ml,HPV6/11/18/31/33/45/52/58的三色混合荧光假病毒浓度为1～3μg/ml.获得了分别含有EGFP、Mcherry和mTagBFP报告基因的9个型别的HPV假病毒,且满足中和检测需要;9个型别单色荧光HPV假病毒的滴度值均在1×104～1×105之间,即它们具有相似的感染滴度.检测HPV九价疫苗免疫的小鼠血清时,单色荧光与三色混合荧光HPV16/33/45假病毒系统所得中和滴度值差异均无统计学意义(P值均>0.05);检测HPV九价疫苗免疫的食蟹猴血清时,单色荧光与三色混合荧光A、B和C组HPV6/11/16/18/31/33/45/52/58假病毒所得中和滴度值差异均无统计学意义(P值均>0.05).结论 成功地建立了三色混合荧光HPV假病毒中和检测系统;验证其与单色荧光HPV假病毒系统具有一致性;证实其可应用于检测HPV九价疫苗免疫血清的免疫原性检测中.

abstractsObjective To establish a triple-color pseudovirion-based neutralization assay (PBNA) and evaluate its capability of detecting immunogenicity of the sera generated by the immunization of HPV 9-valent vaccine. Methods HPV pseudovirus (PsVs) 6/11/16/18/31/33/45/52/58 with the encapsidated fluorescence expressing red fluorescent plasmid N31-MCHREEY,green fluorescent N31-EGFP or blue fluorescent N31-mTagBFP were generated. The concentration of HPV PsVs and the infection titers of HPV PsVs were detected by double-antibody sandwich ELISA and TCID50, respectively. The single- and triple color HPV 16/33/45 PsVs were used to detect the neutralization titers of mice sera immunized with HPV 9-valent vaccine and confirmed the accuracy and specificity of the triple-color PBNAs. Then, the single-and triple color HPV 6/11/18/31/33/45/52/58 PsVs were employed to detect the neutralization titers of cynomolgus macaques sera immunized with HPV 9-valent vaccine and determined whether the triple-color PBNAs could be applied to evaluate the immunogenicity of the sera generated by the immunization of HPV 9-valent vaccine. Results The concentration of HPV16 PsVs encapsulating green, red or blue fluorescent plasmid was 5.0 to 6.0μg/ml and HPV6/11/18/31/33/45/52/59 triple-color HPV PsVs was about 1.0 to 3.0μg/ml. 9 types HPV PsVs containing EGFP, Mcherry or mTagBFP reporter plasmid were obtained and the concentration can meet the need of neutralization detection. 9 types single-color fluorescent HPV PsVs had similar infectivity against 293FT cells with the infection titer values between 1×104 and 1×105. The results of PBNAs showed that there was no significant difference in the anti-HPV neutralization titers of mice sera induced by HPV 9-valent vaccine between single-color and triple-color HPV16/33/45 PsVs (P>0.05). Similarly, there was also no significant difference in the anti-HPV neutralization titers of cynomolgus macaques sera induced by HPV 9-valent vaccine between single-color and triple-color HPV6/11/18/31/33/45/52/58 PsVs (P>0.05). Conclusion We successfully established the triple-color PBNAs and verified the accuracy and specificity of triple-color PBNAs consistent with single-color PBNAs. The triple-color PBNAs can be applied to evaluate the immunogenicity of HPV 9-valent vaccine's immune serum.