Immune response of mice following oral inoculation of recombinant lactobacillus expressing porcine transmissible gastroenteritis virus spike glycoprotein

TANG Li-jie WEI Ying GE Jun-wei REN Xiao-feng WANG Miao XU Yi-gang LI Yi-jing (Northeast Agricultural University,Harbin 150030,China)

TGEV S glycoprotein;;recombinant lactobacillus;;oral immunization in mice;;specific immune response

BALB/c mice were orally immunized with recombinant lactococcus lactis pNZ8112-Sa/NZ900 strain that expresses porcine transmissible gastroenteritis virus(TGEV)Spike(S)glycoprotein.Feces and serum samples were collected on different days after immunization,IgG,IgA in serum and slgA in the feces were examined by indirect ELISA.Changes of T cells proportion in peripheral blood lymphocytes in mice were analyzed by the flow cytometry.The neutralization ability of the aseptically collected intestinal mucin from mice was valuated after the third inoculation.The production of the IgG and IgA antibody from the orally immunized mice could not be determined due to nonspecific interference.The proportion of CD4~+,CD8~+ T cells in peripheral blood lymphocytes in mice showed no difference between the experimental and control groups.Neutralization test showed a neutralizing activity of 1:36 from the intestinal lavage.