Georges-Courbot M C, Lu C Y, Makuwa M, Telfer P, Onanga R, Dubreuil G, Chen Z, Smith S M, Georges A, Gao F, Hahn B H, Marx P A
Centre International de Recherches Medicales, Franceville, Gabon.
J Virol. 1998 Jan;72(1):600-8. doi: 10.1128/JVI.72.1.600-608.1998.
A seroprevalence survey was conducted for simian immunodeficiency virus (SIV) antibody in household pet monkeys in Gabon. Twenty-nine monkeys representing seven species were analyzed. By using human immunodeficiency virus type 2 (HIV-2)/SIVsm, SIVmnd, and SIVagm antigens, one red-capped mangabey (RCM) (Cercocebus torquatus torquatus) was identified as harboring SIV-cross-reactive antibodies. A virus isolate, termed SIVrcm, was subsequently established from this seropositive RCM by cocultivation of its peripheral blood mononuclear cells (PBMC) with PBMC from seronegative humans or RCMs. SIVrcm was also isolated by cocultivation of CD8-depleted RCM PBMC with Molt 4 clone 8 cells but not with CEMx174 cells. The lack of growth in CEMx174 cells distinguished this new SIV from all previously reported sooty mangabey-derived viruses (SIVsm), which grow well in this cell line. SIVrcm was also successfully transmitted (cell free) to human and rhesus PBMC as well as to Molt 4 clone 8 cells. To determine the evolutionary origins of this newly identified virus, subgenomic pol (475 bp) and gag (954 bp) gene fragments were amplified from infected cell culture DNA and sequenced. The position of SIVrcm relative to those of members of the other primate lentivirus lineages was then examined in evolutionary trees constructed from deduced protein sequences. This analysis revealed significantly discordant phylogenetic positions of SIVrcm in the two genomic regions. In trees derived from partial gag sequences, SIVrcm clustered independently from all other HIV and SIV strains, consistent with a new primate lentivirus lineage. However, in trees derived from pol sequences, SIVrcm grouped with the HIV-1/SIVcpz lineage. These findings suggest that the SIVrcm genome is mosaic and possibly is the result of a recombination event involving divergent lentiviruses in the distant past. Further analysis of this and other SIVrcm isolates may shed new light on the origin of HIV-1.
在加蓬，对家养宠物猴进行了猴免疫缺陷病毒（SIV）抗体的血清流行率调查。分析了代表7个物种的29只猴子。通过使用2型人类免疫缺陷病毒（HIV-2）/SIVsm、SIVmnd和SIVagm抗原，鉴定出1只红顶白眉猴（RCM）（Cercocebus torquatus torquatus）携带SIV交叉反应性抗体。随后，通过将这只血清阳性RCM的外周血单个核细胞（PBMC）与血清阴性人类或RCM的PBMC共同培养，从该RCM中分离出一种病毒毒株，称为SIVrcm。通过将去除CD8的RCM PBMC与Molt 4克隆8细胞共同培养也分离出了SIVrcm，但与CEMx174细胞共同培养未分离出。在CEMx174细胞中不能生长这一特性将这种新的SIV与所有先前报道的来自乌黑白眉猴的病毒（SIVsm）区分开来，后者在该细胞系中生长良好。SIVrcm也成功地（无细胞）传播给了人类和恒河猴PBMC以及Molt 4克隆8细胞。为了确定这种新鉴定病毒的进化起源，从感染的细胞培养物DNA中扩增了亚基因组pol（475 bp）和gag（954 bp）基因片段并进行测序。然后在由推导的蛋白质序列构建的进化树中检查SIVrcm相对于其他灵长类慢病毒谱系成员的位置。该分析揭示了SIVrcm在两个基因组区域中明显不一致的系统发育位置。在由部分gag序列推导的树中，SIVrcm与所有其他HIV和SIV毒株独立聚类，这与一个新的灵长类慢病毒谱系一致。然而，在由pol序列推导的树中，SIVrcm与HIV-1/SIVcpz谱系聚类。这些发现表明SIVrcm基因组是嵌合的，可能是过去遥远时期涉及不同慢病毒的重组事件的结果。对这种及其他SIVrcm分离株的进一步分析可能会为HIV-1的起源提供新的线索。
