Construction of the macrophage-derived chemokine and coxsackievirus B3 VP1 fusion gene recombinant adenovirus vaccine and study on its immunological effects in mice.

Objective:To construct macrophage-derived chemokine (MDC) and coxsackievirus B3(CVB3) VP1 fusion gene adenovirus-vectored vaccine Ad/MDC-VP1,and observe its immunological effects in mice.Methods:Adenovirus and recomb-inant adenovirus Ad/MDC-VP1 were constructed with AdEasy-1 system and fusion protein MDC-VP1 was detected.BALB/c mice were randomly divided into experim-ental group and control group with 18 members in each.Mice were immunized twice by intramuscular injection of Ad/MDC-VP1 and adenovirus,respectively,with a two week's interval between each immunization.The titers of sera CVB3 VP1 IgG antib-ody and neutralizing antibody were detected by ELISA and trace neutralization assay,respectively.Three weeks after the last immunization,the spleen lymphocytes prolife-ration and specific CTL cytotoxic activity were tested.Mice in each group were challenged with lethal dose of CVB3,the titers of sera virus were titrated and the protection efficacy against CVB3 was observed.Results:Ad and recombinant adenovirus Ad/MDC-VP1 were successfully constructed and the fusion protein MDC-VP1 was expressed.Based on a comparison between the two groups,the CVB3 VP1 specific IgG,neutralizing antibody levels and CTL activities of the experimental group were significantly enhanced(P0.01).After virus challenged,sera virus titers of the experimental group were lower while its protection rate was higher (P0.01).Conclusion:Cellular and humoral immune responses in the mice could be significantly enhanced by recombinant adenovirus Ad/MDC-VP1,and the protection rate of the mice after virus challenged could be improved.