加州大学旧金山分校和雅培联合发现HCV相关血源性新病毒

 

据报道，研究人员找到了8个完整的HPgV-2病毒毒株，并首次揭示了这种新病毒完整的遗传基因组。HPgV-2病毒的感染和HCV有着紧密的关联，但目前尚不知该病毒是否致病。

 

“基于我们的发现，我们团队用该病毒的全基因组序列对检测试剂进行研发。分别研制出了分子生物学检测和抗体检测来检出血液中的病毒以及特异的病毒免疫反应。我们下一步的目标是，探索这种新病毒是否致病，如果致病，我们就将同血液中心合作共同预防此类新的血源性病毒，确保全世界范围内的输血安全。”雅培应用研究与技术部门副总裁John Hackett 博士表示，“此类研究最终会着眼于开发具有改善医疗实践潜力的新技术。”

 

为明确这种新病毒，UCSF- Abbott VDDC中心的科学家们对新病毒的基因组成进行基因段测序，包括采用了深度测序和超快病原体识别技术，芝加哥大学医疗中心的肝病中心提供了发现病毒的患者血样。

 

“这项研究绘制了人类HPgV-2病毒8个完整基因组和4个局部基因组图谱，帮助了解HPgV-2病毒在受感染的个体中的演变，并对该病毒的基因多样性研究提供了新的线索，”加州大学旧金山分校检验医学副教授，兼UCSF–雅培VDDC 中心主任Charles Chiu博士表示，“此类新的科学发现，是我们同雅培成为长期科研合作伙伴关系的重要原因之一，因为雅培能给医生和检验科提供推动科学知识发现，并不断进行探索的新信息以及新的科技手段，这些都将对人类健康带来深远的影响。”

 

“在过去的五年里，雅培在研发的投入不止翻了一倍，”雅培研发部门副总裁Dennis Gilbert博士表示，“除了新发病原体的探索和监控，我们还将不断提高现有检测试剂的性能，与实验室携手，致力于更好的服务于患者健康。”

 

Berg M G, Lee D, Coller K, et al. Discovery of a Novel Human Pegivirus in Blood Associated with Hepatitis C Virus Co-Infection.[J]. Plos Pathogens, 2015, 11(12).

 

Abstract

 

Hepatitis C virus (HCV) and human pegivirus (HPgV), formerly GBV-C, are the only known human viruses in the Hepacivirus and Pegivirus genera, respectively, of the family Flaviviridae. We present the discovery of a second pegivirus, provisionally designated human pegivirus 2 (HPgV-2), by next-generation sequencing of plasma from an HCV-infected patient with multiple bloodborne exposures who died from sepsis of unknown etiology.HPgV-2 is highly divergent, situated on a deep phylogenetic branch in a clade that includes rodent and bat pegiviruses, with which it shares <32% amino acid identity. Molecular and serological tools were developed and validated for high-throughput screening of plasma samples, and a panel of 3 independent serological markers strongly correlated antibody responses with viral RNA positivity (99.9% negative predictive value). Discovery of 11 additional RNA-positive samples from a total of 2440 screened (0.45%) revealed 93-94% nucleotide identity between HPgV-2 strains. All 12HPgV-2 RNA-positive cases were identified in individuals also testing positive for HCV RNA (12 of 983; 1.22%), including 2 samples co-infected with HIV, but HPgV-2 RNA was not detected in non-HCV-infected individuals (p<0.0001), including those singly infected by HIV (p = 0.0075) or HBV (p = 0.0077), nor in volunteer blood donors (p = 0.0082). Nine of the 12 (75%) HPgV-2 RNA positive samples were reactive for antibodies to viral serologic markers, whereas only 28 of 2,429 (1.15%) HPgV-2 RNA negative samples were seropositive. Longitudinal sampling in two individuals revealed that active HPgV-2 infection can persist in blood for at least 7 weeks, despite the presence of virus-specific antibodies. One individual harboring both HPgV-2 and HCV RNA was found to be seronegative for both viruses, suggesting a high likelihood of simultaneous acquisition of HCV and HPgV-2 infection from an acute co-transmission event. Taken together, our results indicate that HPgV-2 is a novel bloodborne infectious virus of humans and likely transmitted via the parenteral route.