title: Oral immunization induces local and distant mucosal immunity in swine.
abstract: Transmission of porcine reproductive and respiratory syndrome virus (PRRSV) in semen and reproductive disease in pregnant swine might be reduced by vaccines that induce mucosal immunity in the reproductive tract. Cholera toxin (CT), when delivered orally, is a potent mucosal adjuvant and immunogen in swine. To determine if oral immunization additionally elicits immunity at distant mucosal surfaces, we examined antibody responses to CT-B subunit in the reproductive tract and oral cavity. Orally administered CT induced distant mucosal immunity, as measured by antibodies to CT-B subunit in saliva and vaginal secretions. Presentation of PRRSV nucleocapsid as a genetic fusion with CT resulted in local mucosal antibody production, but no response was observed in vaginal secretions. The results demonstrate the feasibility of using orally administered CT for the induction of immunity to reproductive pathogens in swine. However, effective induction of PRRSV-specific immune responses in the reproductive tract requires a better understanding of the mechanisms of antigenicity and adjuvanticity at distant mucosal sites.
authors.affiliation: Department of Veterinary and Biomedical Sciences, University of Minnesota, 1971 Commonwealth Avenue, St. Paul, MN 55108, USA.
authors.forename: Kendra
authors.initials: K
authors.lastname: Hyland
authors.forename: Dennis L
authors.initials: DL
authors.lastname: Foss
authors.forename: Craig R
authors.initials: CR
authors.lastname: Johnson
authors.forename: Michael P
authors.initials: MP
authors.lastname: Murtaugh
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000097:blood; D002772:Cholera Toxin / Q000276:immunology; D005260:Female; D018928:Immunity, Mucosal / Q000276:immunology*; D007413:Intestinal Mucosa / Q000276:immunology; D019316:Porcine respiratory and reproductive syndrome virus / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000276:immunology; D013552:Swine / Q000276:immunology*; D018074:Vaccines, Conjugate / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D011993:Recombinant Fusion Proteins; D018074:Vaccines, Conjugate; D014765:Viral Vaccines; D002772:Cholera Toxin