ABSTRACT
Objective To construct short hairpin RNA (shRNA) recombinant expression vector for herpes simplex virus typeⅡ(HSV-2) UL29 gene and observe its inhibitory effect on HSV-2. Methods Four interference target sites of HSV-2UL29 gene were selected to construct 4 groups of small hairpin RNA respectively,named shRNA recombinant expression vector. The expression vectors were transfected into HEK293 cells with liposome. HEK293 cells were infected with HSV-2 after expression vector being transfected. The viral titer was estimated by end-point titration assay. The level of transcription was estimated by Real-Time PCR method. The expressing effect of protein was detected by Western-blot. Results Recombinant expression vector pGPU6/GFP/Neo-shRNA was constructed successfully. The result of end-point titration assay showed that the viral titer was reduced comparing with blank control (P<0.05). The result of RT-PCR showed that inhibition rates were respectively 28.80%, 59.95%, 66.08%and 36.27% comparing with blank control, and there were significant differences (P < 0.05). The effect of UL29shRNA1461 group was the best one. The result of Western-blot showed that the expressing quantity of ICP8 was reduced. Conclusion Recombinant expression vector pGPU6/GFP/Neo-shRNA can interfere HSV-2 UL29 gene expression from different cell level in vitro, which can inhibit the replication of HSV-2 genome in HEK293 cells. Thus, RNA interference (RNAi) is conducive to the further exploration of viral therapy.
ABSTRACT
BACKGROUND: The serological diagnosis of herpes simplex virus type 2 (HSV-2) infection has pitfalls, in that most of the antibodies against HSV-2 cross-react with HSV-1 and the prevalence of HSV-1 infection is high, especially in Korea. In this study, we tried to establish the serological diagnostic method, which could detect and measure the specific antibodies against HSV- 2 by competitive immunofluorescent staining method as well as competitive ELISA based on the specific monoclonal antibody, MH2-7. METHODS: Immunofluorescent staining and western blot analysis were used to characterize the antigens recognized by MH2-7. Competitive immunofluorescent staining (IF), competitive enzyme immunoassay (ELISA), and western blot analysis were used to detect specific antibodies against HSV-2 in patients' sera. RESULTS: In western blot analysis, the sera from two of six patients clinically diagnosed as genital herpes showed characteristic band patterns, which have been known to be compatible with HSV-2 infection. In competitive immunofluorescent staining, only the sera from the two patients clinically diagnosed as genital herpes and with characteristic band pattern showed competition with MH2-7 monoclonal antibody. The dilution range of the serum showing specific competition was between 1:10 and 1:80. Competitive ELISA was also performed and evaluated as the diagnostic efficacy as ELISA has been known to be advantageous over IF staining in mass screening. The result showed linear dose-response relationship for the patient's sera in inhibition of the reactivity of MH2-7. CONCLUSION: We suggest that the competitive immunofluorescent staining method and competitive ELISA based on the specific monoclonal antibody MH2-7 is a simple, accurate, and precise method, which can be used in serological diagnosis of HSV-2 infection.