title: Contribution of the rev gene to the immunogenicity of DNA vaccines targeting the envelope glycoprotein of HIV.
abstract: BACKGROUND
  The Rev protein of HIV plays a critical role in the export of viral mRNA from the nucleus to the cytoplasm of infected cells. This work examines the effect of introducing rev into a DNA vaccine encoding the Env protein of HIV, and compares the activity of env genes regulated by CMV versus CAG promoters.
  
  
  METHODS
  The HIV Env gp160 encoding gene with or without the rev gene was subcloned into a CMV promoter or a CAG promoter-driven expression plasmid. The Env protein expression of the plasmids was examined in vitro and the HIV-specific immunity was explored in BALB/c mice by an intramuscular route. The immune mice were intraperitoneally challenged with an HIV Env-expression vaccinia virus.
  
  
  RESULTS
  Results indicate that the CAG promoter induces significantly higher levels of Env expression, and better immune responses, than the CMV promoter. Incorporating the rev gene into these plasmids further boosts antigen expression and immunogenicity. Indeed, vaccination with the pCAGrev/env or pCMVrev/env plasmid resulted in 1000-fold lower viral load than that with pCMVenv when the mice were challenged with an Env-expressing vaccinia virus.
  
  
  CONCLUSIONS
  Incorporating rev into a DNA vaccine significantly increases the level of expression and immunogenicity of a co-expressed env gene, and that protective efficacy is further improved by utilizing a pCAG promoter.
authors.affiliation: Department of Bacteriology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan.
authors.forename: Nao
authors.initials: N
authors.lastname: Jounai
authors.forename: Kenji
authors.initials: K
authors.lastname: Okuda
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Kojima
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Toda
authors.forename: Kenji
authors.initials: K
authors.lastname: Hamajima
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohba
authors.forename: Dennis
authors.initials: D
authors.lastname: Klinman
authors.forename: Ke-Qin
authors.initials: KQ
authors.lastname: Xin
mesh_terms: D000818:Animals; D000914:Antibodies, Viral; D002460:Cell Line; D003587:Cytomegalovirus / Q000235:genetics; D005260:Female; D018390:Gene Targeting; D015752:Genes, env; D015757:Genes, rev; D006678:HIV / Q000235:genetics*; D019302:HIV Envelope Protein gp160 / Q000235:genetics*; D007111:Immunity, Cellular; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*; D014616:Vaccinia virus / Q000235:genetics
chemical_list: D000914:Antibodies, Viral; D019302:HIV Envelope Protein gp160; D019444:Vaccines, DNA