Abstract:

【Objective】 The main protective antigen gene segment VP4 of porcine rotavirus was inserted into the surface display vector pNZ8112 of Lactococcus. 【Method】 It was electrotransformed into Lactococcus lactis NZ9000, and the surface display system pNZ8112/NZ9000 was construced. To prove the expression of the exogenous gene, the expression product was detected by SDS-PAGE, Western-blot and immunofluorescence.The reconbinant strain was orally administered to the 6-8 week Balb/c mice. 【Result】 The regional humoral immunity and systematic immunity were detected in the immunized mice.The results indicate that specific sIgA and IgG can be found in fecal pellet, ophthalmic wash, vaginal wash and in the serum after administration.The result of neutralization test indicate the titer of serum is 1:40. 【Conclusion】 All the results indicate that VP4 expressed in the recombinant strain can elicit regional immunity and systematic immunity.

Key words: VP4 protein of porcine rotavirus, lactococcus lactis, surface display, analysis of immunogenicity