Oral Vaccination with the Porcine Rotavirus VP4 Outer Capsid Protein Expressed byLactococcus lactisInduces Specific Antibody Production

Abstract

The objective of this study to design a delivery system resistant to the gastrointestinal environment for oral vaccine against porcine rotavirus.Lactococcus lactisNZ9000 was transformed with segments ofvP4of the porcine rotavirus inserted into the pNZ8112 surface-expression vector, and a recombinantL. lactisexpressing VP4 protein was constructed. An approximately 27 kDa VP4 protein was confirmed by SDS-PAGE , Western blot and immunostaining analysis. BALB/c mice were immunized orally with VP4-expression recombinantL. lactisand cellular, mucosal and systemic humoral immune responses were examined. Specific anti-VP4 secretory IgA and IgG were found in feces, ophthalmic and vaginal washes and in serum. The induced antibodies demonstrated neutralizing effects on porcine rotavirus infection on MA104 cells. Our findings suggest that oral immunization with VP4-expressingL. lactisinduced both specific local and systemic humoral and cellular immune responses in mice.