A mouse model based on replication-competent Tiantan vaccinia expressing luciferase/HIV-1 Gag fusion protein for the evaluation of protective efficacy of HIV vaccine / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Developing an effective vaccine against human immunodeficiency virus type 1 (HIV-1) remains a grand challenge after more than two decades of intensive effort. It is partially due to the lack of suitable animal models for screening and prioritizing vaccine candidates. In this study, we aim to develop a mice model to test HIV-1 vaccine efficacy.</p><p><b>METHODS</b>We constructed a recombinant vaccinia expressing firefly luciferase and HIV-1 Gag fusion protein based on Tiantan strain, an attenuated but replication-competent poxvirus (rTTV-lucgag). By quantifying the luciferase activity as its read out, we defined the biodistribution of Tiantan strain poxvirus in mice inoculated intraperitoneally and attempted to apply this model to evaluate the HIV-1 vaccine efficacy.</p><p><b>RESULTS</b>Our data demonstrated that the rTTV-lucgag was able to express high level of luciferase (< or = 10(6) relative luciferase units (RLU)/mg protein) and HIV-1 Gag (> 3 folds increase comparing to the control). After intraperitoneal inoculation, this virus had dominant replication in the ovary, uterus, and cervix of mice and the luciferase activities in those organs are significantly correlated with viral titers (r(2) = 0.71, P < 0.01). Pre-immunization with an HIV gag DNA vaccine reduced the luciferase activity in ovary from (6006 +/- 3141) RLU/mg protein in control group to (1538 +/- 463) RLU/mg protein in vaccine group (P = 0.1969).</p><p><b>CONCLUSIONS</b>The luciferase activity in ovary could represent viral replication in vivo; this rTTV-lucgag/mice model may be suitable to assess the protective efficacy of cytotoxic T-cell responses to HIV Gag with less tedious work and high through-put.</p>

Effect of GBV-C/HIV coinfection on HIV/AIDS disease progression and HIV replication / 病毒学报

Several research groups have recently reported that persistent GB virus C (GBV-C) co-infected with human immunodeficiency virus (HIV) leads to slower AIDSs disease progression than HIV-1 infection alone. However, these findings were not confirmed by several other studies. To investigate the association between GBV-C replication and plasma HIV loads and CD4+ T cell counts, 203 HIV-1 positive former blood/plasma donors(FBDs) were enrolled from Fuyang city of Anhui Province in China. Plasma specimens were collected from them and were tested for GBV-C using RT-PCR and ELISA. Out of 203 specimens, 52 (25.6%) cases were positive for GBV-C, including 35 male (67.3%) and 17 female (32.7%) cases. No significant association was identified between GBV-C infection and CD4+ T-cell counts or between GBV-C infection and HIV viral loads. Since all the subjects studied were naive to ART, the influence of therapy on AIDS disease progression was ruled out in this study. Overall, our data indicated that HIV-1 positive male FBDs were prone to be infected, GBV-C coinfection with HIV-1 does not significantly influence HIV/AIDS disease progression during the late stage of chronic HIV-1 infection.