title: Long-term memory B-cell responses in recipients of candidate human immunodeficiency virus type 1 vaccines.
abstract: The efficacy and practical application of human immunodeficiency virus type 1 (HIV-1) vaccines may depend in part on the longevity of the immune responses generated, particularly those in the memory compartment. Candidate vaccines based on the HIV-1 envelope glycoproteins generate binding and neutralizing antibodies in humans but there have been no prior studies on the long-term persistence and recall of those responses. We evaluated six healthy, HIV non-infected adults who had received a combination of recombinant canarypox HIV-1 vaccines boosted by gp120 and who had achieved a high serum titer of neutralizing antibody to HIV-1 MN. These individuals were administered a gp160 boost 4-5 years after their last vaccination. Four volunteers had detectable binding and neutralizing antibodies at the time of boosting and all six volunteers exhibited a recall binding and neutralizing antibody response. The antibodies neutralized multiple T cell line-adapted (TCLA) strains of virus, including the vaccine strain, but not primary isolates. These results demonstrate that memory B-cell responses can last for many years following HIV-1 envelope glycoprotein immunization. In principle, similar long-term memory may be possible with improved immunogens that generate broadly cross-reactive neutralizing antibodies.
authors.affiliation: Division of Infectious Diseases, University of California, Davis, Sacramento, CA 92121 USA. tevans@vical.com
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Evans
authors.forename: Sharon
authors.initials: S
authors.lastname: Frey
authors.forename: Heidi
authors.initials: H
authors.lastname: Israel
authors.forename: Joseph
authors.initials: J
authors.lastname: Chiu
authors.forename: Raphaelle
authors.initials: R
authors.lastname: El-Habib
authors.forename: Peter
authors.initials: P
authors.lastname: Gilbert
authors.forename: Alicia
authors.initials: A
authors.lastname: Gaitan
authors.forename: David C
authors.initials: DC
authors.lastname: Montefiori
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology*; D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology*; D015483:HIV Antibodies / Q000097:blood; D019302:HIV Envelope Protein gp160 / Q000276:immunology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory; D014614:Vaccines, Synthetic / Q000276:immunology
chemical_list: D016915:AIDS Vaccines; D015483:HIV Antibodies; D019302:HIV Envelope Protein gp160; D014614:Vaccines, Synthetic