Objective:To investigate the influence of B-lymphocyte chemoattractant on the immune response of CVB3 fusion gene vaccine pcDNA3/C3d3-sVP1.Methods:BALB/c mice were divided into 4 groups randomly, and injected intramuscularly with pcDNA3,pcDNA3/BLC,pcDNA3/C3d3-sVP1 and the combination with the plasmid pcDNA3/BLC and pcDNA3/C3d3-sVP1.At a certain time,they were measured for the titers for neutralizing antibodies,specific CTL cytotoxic activity.The protective efficacy of DNA vaccinations was evaluated by titers of blood viruses and survival rate.Results:The titers for antibodies increased with the time of inoculation.More specifically,the antibody titers (42.17±1.43) and the specific CTL cytotoxic activity (41.3%±3.51%) of the mice in the combination group were remarkably stronger than in the mice with pcDNA3/C3d3-sVP1(P＜0.05),but the virus titers of blood was lower.After lethal CVB3 challenge,the protection of mice from death in the combination group with the plasmid pcDNA3/BLC and pcDNA3/C3d3-sVP1 was 44%.Survival curves indicated that the survive state of combination group was better than others.Conclusion:BLC can strongly enhance the specific immunity induced by C3d3-sVP1.

Objective To construct recombinant adenovirus Ad/MDC-VP1 and investigate its im-muno-boosting effect of the mice primed with the experimental DNA vaccine against Coxsackievirus infection. Methods The recombinant adenovirus Ad/MDC-VP1 was constructed and packaged. The Western blot analysis was used to verify the target protein. BALB/c mice were divided into four groups: Ad/MDC-VP1 group, pcDNA3/MDC-VP1 group, pcDNA3/MDC-VP1 prime-Ad/MDC-VP1 boost group and PBS group. The mice in each group were immunized intramuscularly. The titers of serum IgG and neutralizing antibody were tested by ELISA and trace neutralization assay, respectively. The lymphocytes proliferation activity and specific CTL cytotoxic activity were tested by CCK-8 assay. The mice in each group were challenged with le-thal dose of Coxsackievirus, and the assay of the serum virus titers and the observation of protection efficacy against Coxsackievirus infection were carried out. Results The recombinant adenovirus Ad/MDC-VP1 was successfully constructed and the target protein was expressed. It was observed that the titers of CVB3 VP1 specific antibody, lymphocyte stimulation index, CTL cytotoxicity activities and protection rate of the pcDNA3/MDC-VP1 prime-Ad/MDC-VP1 boost group were much higher than those of the rest groups( P < 0.05), and the titer of serum virus was lower after CVB3 challenged ( P < 0.05 ). Conclusion Both the cellular and humoral immune responses in mice could been significantly enhanced by the pcDNA3/MDC-VP1 prime-Ad/MDC-VP1 boost strategy.

To compare different adjuvant formulation and explore the impact of Calcineurin B subunit(CnB) as adjuvant with a novel HBV protein particle (HBSS1) vaccine in mice, female C57BL/6 mice were immunized HBSS1 with Al(OH)3 only, or a normal dose (5 μg) CnB only, or (CnB+ Al(OH)3) mixture as the adjuvant. All immunized groups were primed twice at 4-week intervals; followed by boosting with recombinant adenoviral based HBV vaccine(rAdSS1) at 10-week intervals. We detected the antigen specific humoral response in mice, including total IgG antibody and IgG subtyping. Then, we characterized the specific cell-mediated immune (CMI) response by detection of γ-interferon secreting splenocytes after stimulaton with S or PreS1 peptide pools. No enhancement of immunity was found among the mice with 5 μg of CnB alone or combined with Al(OH), adjuvanted vaccine,which could not induce higher level of anti-PreS1 and anti-S antibodies and CMI than that of HBSS1 alone or Al(OH)3 adjuvanted vaccines. We concluded that CnB is not an effective adjuvant for a novel HBV subunit vaccine.
Adjuvants, Immunologic ; pharmacology ; Animals ; Calcineurin ; pharmacology ; Female ; Hepatitis B Vaccines ; immunology ; Mice ; Mice, Inbred C57BL ; Protein Subunits

OBJECTIVETo character HBV antigen expression in vitro and in vivo transduced by different transgenic plasmids carrying infectious genome of hepatitis B virus (HBV).

METHODSWe constructed four different lentiviral transfer plasmids (carrying 1.3 full-length genome of HBV, by replacing the EGFP express box in pCS-CG plasmid with HBV genome and with different structural element, named as pCS-HBV1.3 (pCS-HBV1.3 X, pCS-HBV1.3 P, pCS-HBV1.3 N and pCS-HBV1.3 K). We detected the expression of HBsAg and HBeAg by ELISA in different time after transfected Huh 7 cells or hydrodynamic injection into C57 BL/6 mice with transfer plasmids pCS-HBV, respectively.

RESULTSWe detected significant expression of HBsAg over 5 days after transfected Huh 7 cells (in vitro) or hydrodynamic injection into C57 BL/6 mice (in vivo) with transfer plasmids pCS-HBV1.3 X, pCS-HBV1.3 P and pCS-HBV1.3 K. The expression level and dynamics of HBsAg and HBeAg in the sera of mice is consistent with that of in the supernatant of Huh-7 cell. Furthermore, the expression of HBV antigens were modulated by the direction and position of HBV insert, also by some lentiviral vector cis-elements (cPPT and RRE).

CONCLUSIONThe optimal lentiviral transfer plasmids (pCS-HBV1.3 X, pCS-HBV1.3 P and pCS-HBV1.3 K) could be further used for establishment and application of HBV transgenic cell or animal model.

Animals ; Disease Models, Animal ; Female ; Genome, Viral ; Hepatitis B Antigens ; genetics ; Lentivirus ; genetics ; Mice ; Mice, Inbred C57BL ; Plasmids ; Transduction, Genetic ; methods