Summary:Salmonella is of great interest as a potential human immunodeficiency virus vaccine vector because of its ability to elicit potent mucosal and systemic immune responses when administered orally. To determine whether such a vaccine could elicit an immune response in mice, plasmids expressing HIV gp120-LAI were introduced into attenuated S. typhimurium. Three serial doses of 1010 recombinant organisms were administered orally to BALB/c mice at 2-week intervals. Immunized mice but not control mice demonstrated proliferative T cell responses to gp120-LAI, comparable in magnitude to the proliferative responses to Salmonella antigens. Immunized mice had detectable serum and intestinal Salmonella-specific IgA and serum Salmonella-specific IgG. However, no gp120-specific antibody was detected in either serum or intestinal washes. These results indicate that live recombinant Salmonella-based vaccine constructs can induce HIV-specific cellular immune responses in vivo.
Divisions of Infectious Diseases and Medical Oncology, University of Colorado Health Sciences Center, Denver, Colorado; *Division of Infectious Diseases, University of California, San Diego, California; and †Department of Veterans Affairs Medical Center, San Diego, California, U.S.A.
Address correspondence and reprint requests to Dr. Ruth erggren, University of Colorado Health Sciences Center, Box -168, 4200 E. 9th Avenue, Denver, CO 80262, U.S.A.
Manuscript received February 4, 1995; accepted May 9, 1995.
© Lippincott-Raven Publishers.