title: Enhanced cellular immune response against SIV Gag induced by immunization with DNA vaccines expressing assembly and release-defective SIV Gag proteins.
abstract: Codon-optimized genes were synthesized for the SIVmac239 Gag, a mutant Gag with mutations in the major homology region, and a chimeric Gag containing a protein destruction signal at the N-terminus of Gag. The mutant and chimeric Gag were expressed at levels comparable to that observed for the wild-type Gag protein but their stability and release into the medium were found to be significantly reduced. Immunization of mice with DNA vectors encoding the mutant or chimeric Gag induced fourfold higher levels of anti-SIV Gag CD4 T cell responses than the DNA vector encoding the wild-type SIV Gag. Moreover, anti-SIV Gag CD8 T cell responses induced by DNA vectors encoding the mutant or chimeric Gag were found to be 5- to 10-fold higher than those induced by the DNA construct for the wild-type Gag. These results indicate that mutations disrupting assembly and/or stability of the SIV Gag protein effectively enhance its immunogenicity when expressed from DNA vaccines.
authors.affiliation: Department of Microbiology and Immunology, Emory University School of Medicine, 1510 Clifton Road, Room 3086, Rollins Research Center, Atlanta, GA 30322, USA.
authors.forename: Zhigao
authors.initials: Z
authors.lastname: Bu
authors.forename: Ling
authors.initials: L
authors.lastname: Ye
authors.forename: Richard W
authors.initials: RW
authors.lastname: Compans
authors.forename: Chinglai
authors.initials: C
authors.lastname: Yang
mesh_terms: D000086042:3C Viral Proteases; D000595:Amino Acid Sequence; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D005260:Female; D015683:Gene Products, gag / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009154:Mutation; D011993:Recombinant Fusion Proteins / Q000276:immunology; D018449:SAIDS Vaccines / Q000008:administration & dosage / Q000276:immunology*; D016097:Simian Acquired Immunodeficiency Syndrome / Q000517:prevention & control; D015302:Simian Immunodeficiency Virus / Q000276:immunology / Q000378:metabolism / Q000472:pathogenicity; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000276:immunology*; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019065:Virus Assembly
chemical_list: D015683:Gene Products, gag; D011993:Recombinant Fusion Proteins; D018449:SAIDS Vaccines; D019444:Vaccines, DNA; D014764:Viral Proteins; D003546:Cysteine Endopeptidases; D000086042:3C Viral Proteases