INFECTIVITY OF HSIV-VIF CHIMERA IN PIGTAILED MACAQUES

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 目前，还没有HIV-1感染和疾病的动物模型，因为该病毒对人类具有高度特异性。猕猴通常对HIV-1有抵抗力，但猪尾猕猴除外。我们的实验室表明，猪尾猕猴不能表达TRIM 5-alpha的功能亚型，TRIM 5-alpha已被确定为限制HIV-1在恒河猴中复制的宿主因子。因此，HIV-1可能只需要克服另一种宿主因子APOBEC 3G/F的限制，就可以在猪尾猕猴中成功复制。为了验证这一假设，我们与贝勒医学院的J. Kimata博士合作，他设计了一个包含SIVmne的vif基因的HIV-1克隆，使其能够抵消APOBEC 3G/F介导的限制。这种嵌合病毒，HSIV-vif，是96%的HIV-1和4%的SIV。它在刺激的猪尾猕猴血细胞中复制的效率与SIVmne一样。在这项初步研究中，我们接种2猪尾猕猴静脉注射HSIV-vif。两只动物都被感染，感染后1周可检测到血浆病毒血症，并在第2周达到104-105拷贝/ml的峰值。两只动物在第4周时也发生血清转化。然而，血浆病毒载量在感染后3-10个月期间在102-103拷贝/ml之间波动，此后（现在为接种后14个月）保持在基线（d102拷贝/ml）。这些结果表明，除了APOBEC 3G/F和TRIM 5-α之外，尚未鉴定的因子可能有助于体内HSIV-vif感染的控制。目前的工作集中在鉴定这些未鉴定的宿主因子和进一步改进HSIV-vif嵌合体的设计以允许在体内持续复制。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Currently, there is no animal model for HIV-1 infection and disease because the virus is highly specific for humans. Macaques are generally resistant to HIV-1, with the exception being pig-tailed macaques. Our lab showed that pig-tailed macaques are unable to express functional isoforms of TRIM5-alpha, which has been identified as a host factor that restricts the replication of HIV-1 in rhesus monkeys. Therefore, it is possible that HIV-1 will only need to overcome restriction by another host factor, APOBEC3G/F, to replicate successfully in pig-tailed macaques. To test this hypothesis, we collaborated with Dr. J. Kimata of Baylor College of Medicine, who engineered an HIV-1 clone that includes the vif gene of SIVmne, allowing it to counteract APOBEC3G/F-mediated restriction. This chimeric virus, HSIV-vif, is 96% HIV-1 and 4% SIV. It replicates in stimulated pig-tailed macaque blood cells as efficiently as SIVmne. In this pilot study, we inoculated 2 pig-tailed macaques intravenously with HSIV-vif. Both animals became infected, with plasma viremia detectable 1 wk after infection and reaching a peak between 104-105 copies/ml at wk 2. Both animals also seroconverted by wk 4. However, plasma viral load fluctuated between 102-103 copies/ml between 3-10 months after infection and remained at baseline (d102 copies/ml) thereafter (now at 14 months post-inoculation). These results indicate that as yet unidentified factors, in addition to APOBEC3G/F and TRIM5-alpha may contribute to the control of HSIV-vif infection in vivo. Current work is focused on the identification of these unidentified host factors and further improvements on the design of HSIV-vif chimera to allow sustained replication in vivo.