MUCOSAL MODEL OF IMMUNIZATION AGAINST HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 WITH A CHIMERIC INFLUENZA-VIRUS

Previously, we constructed a chimeric influenza virus that expresses t he highly conserved amino acid sequence ELDKWA of gp41 of human immuno deficiency virus type 1 (HIV-1). Antisera elicited in mice by infectio n with this chimeric virus showed neutralizing activity against distan tly related HIV-1 isolates (T. Muster, R. Guinea, A. Trkola, M. Purtsc her, A. Klima, F. Steindl, P. Palese, and H. Katinger, J. Virol, 68:40 31-4034, 1994). In the present study, we demonstrated that intranasal immunizations with this chimeric virus are also able to induce a humor al immune response at the mucosal level. The immunized mice had ELDKWA -specific immunoglobulins A in respiratory, intestinal, and vaginal se cretions. Sustained levels of these secretory immunoglobulins A were d etectable for more than 1 year after immunization. The results show th at influenza virus can be used to efficiently induce secretory antibod ies against antigens from foreign pathogens. Since long-lasting mucosa l immunity in the genital and intestinal tracts might be essential for protective immunity against HIV-1, influenza virus appears to be a pr omising vector for HIV-1-derived immunogens.