Abstract: Lactobacillus casei strain 393 was selected as oral vaccine carrier for the expression of Porcine Parvovirus (PPV) main immune protective antigen VP2 protein. The constructed pPG-VP2 plasmid expressing PPV VP2 protein on cell surface was electroporated into Lactobacillus casei 393 generating recombinant strain pPG-VP2/L.casei393.The interest protein was detected by SDS-PAGE、Western-blot and indirect immunofluorescence after induced by 2% Lactose in MRS broth. Oral immunization of BALB/c mice were received with recombinant strain harboring pPG-VP2 and L.casei393 harboring pPG. Specific anti-PPV VP2 secret immunoglobulin A (sIgA) antibody was detected by indirect enzyme linked immunosorbent assay (ELISA) in the feces and intestines mucus after orogastric immunization, and anti-PPV VP2 immunoglobulin G (IgG) antibody was detected by indirect ELISA in the serum of immunized mice. The results indicated that the mice immunized with pPG-VP2/L.casei393 could produce clear anti-PPV antibody level. Our work establish important material basement for the development of PPV oral vaccine.

Key words: Porcine Parvovirus, VP2 protein, Lactobacillus casei 393, surface expression, sIgA, IgG