title: Induction of neutralizing antibodies against HTLV-I envelope proteins after combined genetic and protein immunizations in mice.
abstract: Direct DNA inoculation can induce both protective humoral and cellular responses against several viruses. The HTLV-I envelope glycoproteins are the major antigens recognized by sera of HTLV-I infected patients that generate neutralizing immune responses in vitro and in vivo. We compared immune responses elicited after a single inoculation of two plasmids encoding the complete HTLV-I envelope proteins followed or not by gp62 Baculovirus recombinant protein boosts in BALB/c mice. First, we observe that the coexpression of env and rex genes is not sufficient to raise a detectable specific humoral response after a single DNA inoculation. Protein boosts generated a high antibody response in mice primed with DNA expressing HTLV-I envelope proteins as compared to naive and negative control vector primed groups. This humoral response presented high neutralizing antibody titers. These results suggest that a single inoculation of DNA expressing HTLV-I env gene can stimulate memory B-cell clones that are able to respond effectively to subsequent encounters with HTLV-I envelope proteins and a specific cellular T helper cell response in mice.
authors.affiliation: INSERM U271, Lyon, France.
authors.forename: M P
authors.initials: MP
authors.lastname: Grange
authors.forename: M A
authors.initials: MA
authors.lastname: Armand
authors.forename: G
authors.initials: G
authors.lastname: Audoly
authors.forename: D
authors.initials: D
authors.lastname: Thollot
authors.forename: C
authors.initials: C
authors.lastname: Desgranges
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D015686:Gene Products, env; D005822:Genetic Vectors / Q000235:genetics; D015481:HTLV-I Antibodies / Q000187:drug effects / Q000276:immunology*; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D006801:Humans; D007106:Immune Sera / Q000494:pharmacology; D007114:Immunization / Q000379:methods; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D010957:Plasmids / Q000235:genetics / Q000276:immunology; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000494:pharmacology; D019444:Vaccines, DNA / Q000235:genetics / Q000494:pharmacology*; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology
chemical_list: D015686:Gene Products, env; D015481:HTLV-I Antibodies; D007106:Immune Sera; D011994:Recombinant Proteins; D019444:Vaccines, DNA; D014759:Viral Envelope Proteins