Akahata Wataru, Ido Eiji, Akiyama Hisashi, Uesaka Hiromi, Enose Yoshimi, Horiuchi Reii, Kuwata Takeo, Goto Toshiyuki, Takahashi Hidemi, Hayami Masanori
Laboratory of Viral Pathogenesis, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan.
Laboratory Animal Research Center, Toyama Medical and Pharmaceutical University, Toyama 930-0152, Japan.
J Gen Virol. 2003 Aug;84(Pt 8):2237-2244. doi: 10.1099/vir.0.19082-0.
A DNA vaccination regime was investigated previously in rhesus macaques using a full-genome human immunodeficiency virus type 1 (HIV-1) plasmid, which, due to mutations in the nucleocapsid (NC) proteins, produced only non-infectious HIV-1 particles (Akahata et al., Virology 275, 116-124, 2000). In that study, four monkeys were injected intramuscularly 14 times with the plasmid. All of them showed immunological responses against HIV-1 and partial protection from challenge with a simian immunodeficiency virus/HIV (SHIV) chimeric virus. To improve this DNA vaccination regime, the plasmid used for vaccination was changed. In the present study, four macaques were injected intramuscularly eight times with a full-genome SHIV plasmid that produces non-infectious SHIV particles. CTL activities were higher than those observed in monkeys vaccinated previously with the HIV-1 plasmid. In all macaques vaccinated, peak plasma virus loads after homologous challenge with SHIV were two to three orders of magnitude lower than those of the naive controls, and virus loads fell below the level of detection at 6 weeks post-challenge. This suggested that the vaccination regime in this study was partially effective and better than the previous regime.
