Observation of the immunization effect of HSV-2 ICP27377-513DNA vaccine combined with IL-15 DNA vaccine

HAN Xiao-yan; WU Zhen-cun; ZHOU Yan; JIA Feng-zhen; WANG Chen-hong

doi:10.13820/j.cnki.gdyx.20233272

Abstract：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-ICP273n-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-y in 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 quanti-tative 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-γ and 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 pcD-NA3.1-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.