单纯疱疹病毒2型ICP27_(377-513)核酸疫苗联合IL-15核酸疫苗免疫效果的观察

Observation of the immunization effect of HSV-2 ICP27_(377-513) DNA vaccine combined with IL-15 DNA vaccine

目的构建表达单纯疱疹病毒2型感染细胞蛋白27(infected cells protein 27,ICP27)的重组质粒pcDNA3.1-ICP27377-513并观察白细胞介素(IL)-15核酸疫苗联合HSV-2-ICP27377-513核酸疫苗的免疫效果。方法采用分子克隆技术构建pcDNA3.1-ICP27377-513重组质粒。将BALB/c雌性小鼠随机分为pcDNA3.1-ICP27377-513联合pcDNA3.1-IL-15(pIL-15)组、pcDNA3.1-ICP27377-513组、pcDNA3.1组和pIL-15组,共免疫3次,每次间隔2周。末次免疫后28 d取血,用微量中和实验法检测血清中特异性中和抗体,ELISA法检测血清中IL-4、IL-2和干扰素-γ(IFN-γ)水平。阴道给予致死量HSV-2攻击小鼠,分别于接种后3 d、7 d和14 d收集阴道冲洗液,用荧光定量PCR法检测生殖道病毒载量。结果pcDNA3.1-ICP27377-513联合pIL-15组和pcDNA3.1-ICP27377-513组中和抗体效价分别为40.00±8.16、28.67±4.47,但两组间差异无统计学意义(P>0.05)。pcDNA3.1-ICP27377-513联合pIL-15组IFN-γ、IL-4水平明显高于pcDNA3.1-ICP27377-513组(P<0.05),但IL-2水平两组间差异无统计学意义(P>0.05)。阴道给予致死量HSV-2攻击后,pcDNA3.1-ICP27377-513联合pIL-15组和pcDNA3.1-ICP27377-513组小鼠阴道冲洗液中病毒载量随着时间延长逐渐减低,pcDNA3.1-ICP27377-513联合pIL-15组和pcDNA3.1-ICP27377-513组相比差异有统计学意义(P<0.05)。结论IL-15核酸疫苗联合HSV-2-ICP27377-513核酸疫苗对小鼠有较好的免疫保护作用。

Objective To construct a recombinant plasmid pcDNA3.1-ICP27377-513 expressing infected cells protein 27(ICP27)of herpes simplex virus type 2(HSV-2)and observe the immune effect of IL-15 DNA vaccine combined with HSV-2-ICP27377-513 DNA vaccine.Methods Molecular cloning technology was used to construct the pcDNA3.1-ICP27377-513 recombinant plasmid.Female BALB/c mice were randomly divided into four groups:pcDNA3.1-ICP27377-513 combined with pcDNA3.1-IL-15(pIL-15)group,pcDNA3.1-ICP27377-513 group,pcDNA3.1 group,and pIL-15 group.Mice were immunized three times at two-week intervals.Blood was collected 28 days after the final immunization to detect specific neutralizing antibodies in the serum using a micro-neutralization assay,and the levels of IL-4,IL-2,and IFN-γin serum were measured using ELISA.Mice were challenged with a lethal dose of HSV-2 in the vagina,and vaginal lavage fluid was collected at 3,7,and 14 days post-inoculation to detect viral load using quantitative fluorescence PCR.Results The neutralizing antibody titers in the pcDNA3.1-ICP27377-513 combined with pIL-15 group(first combined group)and pcDNA3.1-ICP27377-513 group were 40.00±8.16 and 28.67±4.47,respectively,with no statistically significant difference between the two groups(P>0.05).The levels of IFN-γand IL-4 in the first combined group were significantly higher than those in the pcDNA3.1-ICP27377-513 group(P<0.05),but there was no significant difference in IL-2 levels between the two groups(P>0.05).After vaginal inoculation with a lethal dose of HSV-2,the viral load in vaginal lavage fluid gradually decreased over time in both the first combined group and the pcDNA3.1-ICP27377-513 group,with a statistically significant difference between the two groups(P<0.05).Conclusion IL-15 DNA vaccine combined with HSV-2-ICP27377-513 DNA vaccine has a good immune protective effect on mice.