Faculty of Environmental Science and Engineering and Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, China.
PLoS One. 2011;6(10):e21151. doi: 10.1371/journal.pone.0021151. Epub 2011 Oct 6.
GB virus C (GBV-C) is prevalent globally and particularly among individuals at risk of parental exposures. Based on genetic diversity, this virus is now classified into six genotypes and many subtypes with distinct geographical distribution. In this study, 120 Injecting Drug Users (IDUs) were recruited from Yunnan province, China. Among them, 43 (35.8%) were positive for GBV-C RNA, 70 (58.3%) and 103 (85.8%) sero-positive for HIV-1 and HCV respectively. This revealed 18.3% of IDUs having GBV-C/HIV/HCV triple infection, which is significantly higher than 7.5% of GBV-C/HIV-1 and 10% of GBV-C/HCV dual infection rates (P<0.05). Based on 5'UTR sequences, the identified 43 viral isolates can be classified into three phylogenetic groups: one (2.3%) and two (4.7%) belonged to genotype 3 and 4, respectively, and the remaining 40 (93%) formed a new group with 97% of bootstrap support. This new GBV-C group was further confirmed by characterizing the E2 region and full-length genome sequences. Analysis of 187 nt 5'UTR sequence showed three previous reported isolates from Southeast Asia were re-classified into this new group. It implies they have the same origin with strains from Yunnan. Although we provisionally assigned this new group as GBV-C genotype 7, a simpler five groups of GBV-C nomenclature is recommended. Genotype 4, 6 and the newly designated genotype 7 could be reclassified as one group, which may represent a single GBV-C genotype. The classification of the other four groups was corresponding to that of previous reported genotype 1, 2, 3 and 5. Furthermore, the diversity of amino acid sequence in the E2 region was analyzed. The inhibitory effect of GBV-C genotype 7 on HIV-1 cell entry could be deduced. Since GBV-C may have a beneficial effect on AIDS disease progression and interact with HCV during co-infection, this finding may raise interests in future studies on this virus that was previously thought to be a "non-pathogenic virus".
GB 病毒 C（GBV-C）在全球范围内广泛流行，尤其是在有母婴暴露风险的人群中更为常见。根据遗传多样性，该病毒现已被分为 6 种基因型和许多具有不同地理分布的亚型。在这项研究中，共招募了来自中国云南省的 120 名静脉吸毒者（IDU）。其中，43 名（35.8%）的 GBV-C RNA 阳性，70 名（58.3%）和 103 名（85.8%）的 HIV-1 和 HCV 血清阳性。这表明 18.3%的 IDU 同时感染了 GBV-C/HIV/HCV，明显高于同时感染 HIV-1 和 HCV 的 7.5%和双重感染的 10%（P<0.05）。基于 5'UTR 序列，鉴定出的 43 个病毒分离株可分为 3 个进化群：1 个（2.3%）和 2 个（4.7%）分别属于基因型 3 和 4，其余 40 个（93%）形成一个新群，支持率为 97%。通过对 E2 区和全长基因组序列的特征分析，进一步证实了这个新的 GBV-C 组。对 187 个核苷酸 5'UTR 序列的分析表明，来自东南亚的 3 个先前报道的分离株被重新分类到这个新的组中。这表明它们与来自云南的病毒株具有相同的起源。尽管我们暂定将这个新的组命名为 GBV-C 基因型 7，但建议采用更简单的 GBV-C 命名法，将基因型 4、6 和新指定的基因型 7 重新分类为一组，这可能代表单一的 GBV-C 基因型。其他四个组的分类与之前报道的基因型 1、2、3 和 5 相对应。此外，还分析了 E2 区氨基酸序列的多样性，可以推断出 GBV-C 基因型 7 对 HIV-1 细胞进入的抑制作用。由于 GBV-C 可能对 AIDS 疾病进展有有益的影响，并在合并感染时与 HCV 相互作用，因此这一发现可能会引起人们对这种以前被认为是“非致病性病毒”的病毒的未来研究的兴趣。
