title: HIV-1 epitopes exposed by hybrid hepatitis B core particles affect proliferation of peripheral blood mononuclear cells from HIV-1 positive donors.
abstract: Hepatitis B virus core protein (HBc) in particulate form is a potent immunogen for the design of vaccines with a broad T-cell reactivity. Hybrid HBc proteins with N-terminal insertions of human immunodeficiency virus (HIV-1) B- and T-cell epitopes from gp41 and p34 pol, respectively, were constructed HBc hybrids formed particles with HIV-1 epitopes exposed on the surface. The proliferative response of peripheral blood mononuclear cells (PBMC) from HIV-1 infected donors to the hybrids was studied in vitro and compared to that of synthetic peptides representing the same HIV-1 sequences. The epitope from p34 pol induced PBMC proliferation both when inserted into HBc and as a peptide. The epitope from gp41, when inserted into HBc, and to a lesser extent the relevant peptide caused a decreased reactivity. The inhibitory effect of the HBc hybrid carrying the gp41-epitope was pronounced even in the HIV-1 infected donors with proliferative responses to HBc. The similarity between the mode of action of the peptides and hybrid HBcs implies either correct processing of the latter or T-cell recognition of HIV-1 epitopes in the intact hybrid HBc particles.
authors.affiliation: Swedish Institute for Infectious Disease Control, Stockholm, Sweden.
authors.forename: M G
authors.initials: MG
authors.lastname: Isaguliants
authors.forename: S
authors.initials: S
authors.lastname: Nordlund
authors.forename: M
authors.initials: M
authors.lastname: Sällberg
authors.forename: V D
authors.initials: VD
authors.lastname: Smirnov
authors.forename: U
authors.initials: U
authors.lastname: Rudén
authors.forename: B
authors.initials: B
authors.lastname: Wahren
mesh_terms: D000595:Amino Acid Sequence; D000939:Epitopes; D015684:Gene Products, pol / Q000235:genetics / Q000276:immunology; D015700:HIV Envelope Protein gp41 / Q000235:genetics / Q000276:immunology; D006679:HIV Seropositivity / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006512:Hepatitis B Core Antigens / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000276:immunology
chemical_list: D000939:Epitopes; D015684:Gene Products, pol; D015700:HIV Envelope Protein gp41; D006512:Hepatitis B Core Antigens; D011993:Recombinant Fusion Proteins