Human alphaherpesvirus 2 (HSV-2) is the main pathogen resulting human genital herpes, which poses a major threat to the socio-economic development, while there is no effective vaccine. In this study, we developed a novel lipopolyplex (LPP)-delivered mRNA vaccine expressing the HSV-2 envelope glycoprotein gD and evaluated its immunogenicity in mice. The mRNA vaccine was prepared from the genetically modified gD mRNA synthesized in vitro combined with the LPP delivery platform and it was named gD-ORI mRNA. The expression of gD antigen in the mRNA vaccine was validated in vitro by Western blotting and indirect immunofluorescence assay, then the immune responses induced by this mRNA vaccine in mice were evaluated. The immunization with gD mRNA alone induced strong humoral and cellular immune responses in mice. Robust and long-lasting gD-specific IgG antibodies were detected in the mouse serum after booster immunization with gD-ORI mRNA. The immunized mice exhibited a Th1/Th2 balanced IgG response and robust neutralizing antibodies against HSV-2, and a clear dose-response relationship was observed. The gD-specific IgG antibodies were maintained in mice for a long time, up to 18 weeks post-booster immunization. At the same time, multifunctional gD-specific CD4⁺ and CD8⁺ T cells in vaccinated mice were detected by intracellular cytokine staining (ICS). This novel gD-expressing mRNA vaccine delivered by LPP induces strong and long-lasting immune responses in mice post booster immunization and has a promising prospect for development and application. This study provides scientific evidence and reference for the development of a new mRNA vaccine for HSV-2.
Animals ; Herpesvirus 2, Human/genetics* ; Viral Envelope Proteins/genetics* ; Mice ; Herpes Genitalis/immunology* ; RNA, Messenger/immunology* ; Female ; Mice, Inbred BALB C ; Antibodies, Viral/blood* ; mRNA Vaccines/immunology* ; Antibodies, Neutralizing/blood* ; Humans

Objective:To establish and optimize a novel method, focus forming assay (FFA), for quantitation of influenza A virus (FluA) and compare its application performance with traditional plague forming assay (PFA).Methods:The foci chromogenic effects of three peroxidase substrates in immunostaining were compared. The PFA and FFA methods were used to explore FluA incubation times and plaque morphology on 12-well plates, and to determine optimal incubation times and virus adsorption volumes for different FluA subtypes on 96-well plates. The correlation between FFA and PFA was evaluated, and the optimized FFA was applied to the in vitro antiviral efficacy analysis of Favipiravir and neutralization test against different subtypes of FluA. Results:TRUEBLUE substrate was identified as the optimal substrate for foci visualization. Compared with the PFA, the FFA showed improved sensitivity and reduced detection time in FluA titration, and good correlation was shown between the two methods′ results. By replacing the 96-well plate with the 12-well plate for FFA titration of different subtypes of FluA, the detection time was shortened, and the amount of serum samples used could be further reduced by optimizing the virus adsorption volume. The half-maximal effective concentration of favipiravir against influenza viruses assessed by the FFA and PFA methods showed no significant difference, and was consistent with the results obtained from quantitative PCR. Additionally, the focus reduction neutralization test and hemagglutination inhibition assays demonstrated strong correlation in determining antibody titers against FluA in serum neutralization assays.Conclusions:The improved FFA method developed here provides a more efficient experimental tool for FluA titration, antiviral drug screening and broad-spectrum vaccine evaluation.

Objective:To establish and optimize a novel method, focus forming assay (FFA), for quantitation of influenza A virus (FluA) and compare its application performance with traditional plague forming assay (PFA).Methods:The foci chromogenic effects of three peroxidase substrates in immunostaining were compared. The PFA and FFA methods were used to explore FluA incubation times and plaque morphology on 12-well plates, and to determine optimal incubation times and virus adsorption volumes for different FluA subtypes on 96-well plates. The correlation between FFA and PFA was evaluated, and the optimized FFA was applied to the in vitro antiviral efficacy analysis of Favipiravir and neutralization test against different subtypes of FluA. Results:TRUEBLUE substrate was identified as the optimal substrate for foci visualization. Compared with the PFA, the FFA showed improved sensitivity and reduced detection time in FluA titration, and good correlation was shown between the two methods′ results. By replacing the 96-well plate with the 12-well plate for FFA titration of different subtypes of FluA, the detection time was shortened, and the amount of serum samples used could be further reduced by optimizing the virus adsorption volume. The half-maximal effective concentration of favipiravir against influenza viruses assessed by the FFA and PFA methods showed no significant difference, and was consistent with the results obtained from quantitative PCR. Additionally, the focus reduction neutralization test and hemagglutination inhibition assays demonstrated strong correlation in determining antibody titers against FluA in serum neutralization assays.Conclusions:The improved FFA method developed here provides a more efficient experimental tool for FluA titration, antiviral drug screening and broad-spectrum vaccine evaluation.

Objective:To construct a novel respiratory syncytial virus (RSV) vaccine based on a recombinant influenza virus vector and evaluate its immune protective effects in mice.Methods:A recombinant H1N1 influenza A virus (IAV) expressing the extracellular domain (Gecto) of RSV A2 G protein was constructed and rescued, named as PR8NAGecto/WSN. After in vitro verification of the Gecto expression and PR8NAGecto/WSN growth kinetics, a single dose of PR8NAGecto/WSN was used to immunize BALB/c mice through intranasal administration to evaluate the efficacy of PR8NAGecto/WSN by assessing humoral (IgG, neutralizing antibody), mucosal (IgA) and cellular immunity (IFN-γ ELISPOT). Four weeks after immunization, the mice were challenged with RSV A2 or RSV B9320 to evaluate the protective effects of PR8NAGecto/WSN by analyzing mouse body weight changes, lung tissue virus titers and pathological changes. Results:A single-dose intranasal immunization with PR8NAGecto/WSN induced robust humoral, mucosal and cellular immunity in mice. Moreover, the mice in the immunized group had lower lung virus loads and mild lung pathological damages following the challenge with RSV A or RSV B subtype as compared with the control group.Conclusions:A single-dose intranasal immunization with PR8NAGecto/WSN induces robust immunity and provide protection against RSV A and B challenges in mice. This study provides new ideas and reference for the development of novel mucosal vaccines against RSV.

Objective:To construct a primary nanobody library for human papillomavirus 16(HPV16)L1 protein and obtain a nanobody specific to HPV16 L1 through selection and identification.Methods:HPV16 L1 protein was used as antigen to immunize alpaca,and a primary antibody library was constructed using phage display technology.After three rounds of screening,positive clones were identified by ELISA.The VHH sequence of the strongest positive clone was used for eukaryotic expression.The target nanobody was obtained after affinity purification,gel filtration chromatography,SDS PAGE and WB identification.The affinity between the nanobody and HPV16 L1 protein was evaluated using surface plasmon resonance(SPR)technology.The cytotoxicity of the nanobody was detected using CCK-8 assay.The neutralizing activity of nanobody against HPV16 pseudovirus was detected using a luciferase reporter gene assay.Results:The primary library was constructed with a capacity of 1.304×1010 and an abundance of 6.5×109 clones/mL.ELISA identified 36 positive clones.Protein monomer and dimers were expressed and purified,and the target nanobody(designated as"Nb")was successfully identified.The binding affinity of Nb to HPV16 L1 protein was 35.41 nmol/L.There was no significant difference in HaCat cell proliferation activity between Nb group and blank group(P>0.05).Compared to the negative group,both 0.1 and 1 μmol/L Nb inhibited pseudovirus infection in 293FT cells(all P<0.01).Conclusion:This study successfully obtained a nanobody with high purity and strong affinity that exhibited no cytotoxicity to epithelial cells and effectively inhibited HPV16 pseudovirus infection in 293FT cells.The nanobody provides a promising candidate antibody-based drug for the prevention and treatment of HPV 16 infection.

BACKGROUND: The association of tumor necrosis factor alpha (TNF-α) gene polymorphisms with the onset and development of ankylosing spondylitis (AS) has been the focus of studies on AS in the field of genetics.OBJECTIVE: To explore the association of the polymophisms of TNF-α promoter gene at positions-308 and -238 with AS susceptibility and clinical pathological changes.DESIGN: A case-control study.SETTING:The Rheumatic Immunology Department of Changhai Hospital of the Second Military Medical University of Chinese PLA.PARTICIPANTS: Totally, 108 AS patients were recruited from Rheumatic Immunology Department of Changhai Hospital, Second Military Medical University of Chinese PLA from January 1999 to December 2003 ,they had no kinship. The ratio of men to women was 5.3: 1. They aged from 13 to 71 (30-± 12) years old, and AS was divided into Ⅰ- Ⅳ radiographic stages according to the sacro-iliac joint damage. A total of 100 healthy controls were randomly selected from the blood donators(Shanghai Hospital) who were aged from 19 -56 (33 ±9) years old, and the ratio of men to women was 4.9: 1. Informed consent was obtained from all the subjects.ti-coagulated with EDTA. Polymerase chain reaction amplification and purification of the TNF-α promoter region was made and the sequence of polymerase chain reaction products was examined and displayed by Chromas 1.62 softcorresponding radiographic stage of sacro-iliac joint damage was assessed to investigate the influence of gene polymorphisms on AS.MAIN OUTCOME MEASURES: DNA direct sequencing method was used to detect -238 and -308 allele phenotypes for investigating the association with clinical presentations.G and -238G/A allele was 98.1% (106 cases) and1. 9% (2 cases) respectively in AS group and 95.0% (95 cases) and 5.0% (5 cases) respecquency of TNF-α promoter gene at positions -308. 1.1(G/G) and - 308.1.2(G/A) alleles was 82.4% (89 cases) and 17.6% (192 cases) respectively in AS group, which was not significantly different compared respectively with 85.0% (85 cases) and 14.0% (14 cases) of the control of sacro-iliac joint damage and the frequency of TNF-α promoter gene at the position of - 308 (G/G) and (G/A): AS patients with(G/G) phenotype who were confirmed of radiographic stage Ⅰ, Ⅱ, Ⅲ, and Ⅳ were observed in 3/35/40/11cases,compared with (G/A) phenotype of 1/12/6/0 cases.The difference was statistically significant (χ2GMH = 4.77, P ＜ 0.05 ).CONCLUSION: Our data suggest that the polymorphisms of TNF-α promoter gene at positions of - 238 and - 308 allele has no association with AS susceptibility, but the polymorphisms of TNF - α promoter gene at the position of -308 might exert great influence on AS according to the radiographic stage of sacro-iliac joint damage.