Study On The Humoral Immunity Of Pseudomonas Aeruginosa Fusion DNA Vaccines Encoding VP22-outer Membrane Protein F Or VP22-type B Flagellins

Objective: Evaluate whether Herpes Simplex Virus type I tegument protein VP22 will enhance the humoral immune response of DNA vaccines constructed by Pseudomonas aeruginosa outer membrane protein F or type B flagellins. This study would provide foundation for the development of better Pseudomonas aeruginosa DNA vaccines encoding VP22-antigen fusion.Methods: 1.DNA vaccines including p VAX1-Opr F, p VAX1-VP22-Opr F, p VAX1-Opr F-VP22, p VAX1-Fla B, p VAX1-Fla B-VP22 and p VAX1-VP22 were extrated; 2.The BALB/c mouse were immunized intramuscularly by DNA vaccines mediated by the in vivo transfection reagent. The antiserum of mouse were prepared after the three immunization. 3. The specificity binding of the antiserum and antigens were detected by Western blot. 4.The antiserum titers were analyzed by indirect Elisa and the differences of antiserum titer between groups were analyzed by analysis of variance or t test statistical methods.Results: 1.The Western blot showed the antiserum against p VAX1-Opr F, p VAX1-VP22-Opr F and p VAX1-Opr F-VP22 were specific binding to Opr F. The antiserum against p VAX1-Fla B and p VAX1-Fla B-VP22 were specific binding to Fla B. 2. The indirect Elisa showed the p VAX1-Opr F-VP22 group produced a significantly higher titer of Ig G than the p VAX1-Opr F and p VAX1-VP22-Opr F groups(P<0.05),while there was no significant difference between the p VAX1-VP22-Opr F group and the p VAX1-Opr F group(P>0.05). The titer level of Ig G in the PVAX1-Flab-VP22 group was significantly higher than the p VAX1-Flab group(P<0.05).Conclusion: DNA vaccine single expressing antigens(Opr F and Fla B) and fusion DNA vaccines encoding VP22/Opr F or VP22/Fla B can induce specific humoral immune response in mice. However, the fusion DNA vaccines encoding N-terminal VP22-fused antigens(Opr F and Fla B) can significantly enhance the humoral immune efficacy.