Enhanced murine respiratory tract IgA antibody response to oral influenza vaccine when combined with a lipoidal amine (avridine)

The adjuvant activity of avridine, a synthetic lipoidal amine, incorporated in liposomes, was studied in mice immunized orally with killed influenza virus vaccine (A/PR/8/34, H1N1). Coadministration of avridine-containing liposomes and viral antigen enhanced the remote-site IgA antibody response in the respiratory tract without a concomitant serum antibody response or side effects. The results support the possible use of mucosal adjuvants for oral immunization against respiratory pathogens.