Saenz Dyana T, Teo Wulin, Olsen John C, Poeschla Eric M
Molecular Medicine Program, Guggenheim 18, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
J Virol. 2005 Dec;79(24):15175-88. doi: 10.1128/JVI.79.24.15175-15188.2005.
The Ref1 and Lv1 postentry restrictions in human and monkey cells have been analyzed for lentiviruses in the primate and ungulate groups, but no data exist for the third (feline) group. We compared feline immunodeficiency virus (FIV) to other restricted (human immunodeficiency virus type 1 [HIV-1], equine infectious anemia virus [EIAV]) and unrestricted (NB-tropic murine leukemia virus [NB-MLV]) retroviruses across wide ranges of viral inputs in cells from multiple primate and nonprimate species. We also characterized restrictions conferred to permissive feline and canine cells engineered to express rhesus and human TRIM5alpha proteins and performed RNA interference (RNAi) against endogenous TRIM5alpha. We find that expression of rhesus or human TRIM5alpha proteins in feline cells restricts FIV, impairing pseudotyped vector transduction and viral replication, but rhesus TRIM5alpha is more restricting than human TRIM5alpha. Notably, however, canine cells did not support restriction by human TRIM5alpha and supported minimal restriction by rhesus TRIM5alpha, suggesting that these proteins may not function autonomously or that a canine factor interferes. Stable RNAi knockdown of endogenous rhesus TRIM5alpha resulted in marked increases in FIV and HIV-1 infectivities while having no effect on NB-MLV. A panel of nonprimate cell lines varied widely in susceptibility to lentiviral vector transduction, but normalized FIV and HIV-1 vectors varied concordantly. In contrast, in human and monkey cells, relative restriction of FIV compared to HIV-1 varied from none to substantial, with the greatest relative infectivity deficit for FIV vectors observed in human T-cell lines. Endogenous and introduced TRIM5alpha restrictions of FIV could be titrated by coinfections with FIV, HIV-1, or EIAV virus-like particles. Arsenic trioxide had complex and TRIM5alpha-independent enhancing effects on lentiviral but not NB-MLV infection. Implications for human gene therapy are discussed.
针对灵长类和有蹄类动物群体中的慢病毒，已对人类和猴细胞中的Ref1和Lv1进入后限制进行了分析，但关于第三个（猫科）群体的数据尚不存在。我们在多种灵长类和非灵长类物种的细胞中，在广泛的病毒输入范围内，将猫免疫缺陷病毒（FIV）与其他受限制的（人类免疫缺陷病毒1型[HIV-1]、马传染性贫血病毒[EIAV]）和不受限制的（NB嗜性鼠白血病病毒[NB-MLV]）逆转录病毒进行了比较。我们还对经工程改造以表达恒河猴和人类TRIM5α蛋白的允许性猫和犬细胞所赋予的限制进行了表征，并针对内源性TRIM5α进行了RNA干扰（RNAi）。我们发现，恒河猴或人类TRIM5α蛋白在猫细胞中的表达会限制FIV，损害假型载体转导和病毒复制，但恒河猴TRIM5α的限制作用比人类TRIM5α更强。然而，值得注意的是，犬细胞不支持人类TRIM5α的限制作用，并且对恒河猴TRIM5α的限制作用支持程度极小，这表明这些蛋白可能无法自主发挥作用，或者存在一种犬类因子进行干扰。内源性恒河猴TRIM5α的稳定RNAi敲低导致FIV和HIV-1感染性显著增加，而对NB-MLV没有影响。一组非灵长类细胞系对慢病毒载体转导的敏感性差异很大，但标准化的FIV和HIV-1载体的变化趋势一致。相比之下，在人类和猴细胞中，FIV相对于HIV-1的相对限制程度从无到有很大差异，在人类T细胞系中观察到FIV载体的相对感染性缺陷最大。FIV的内源性和引入的TRIM5α限制作用可通过与FIV、HIV-1或EIAV病毒样颗粒共感染来进行滴定。三氧化二砷对慢病毒感染具有复杂且不依赖于TRIM5α的增强作用，但对NB-MLV感染没有影响。文中讨论了对人类基因治疗的影响。
