Molecular features of Hepatitis E Virus circulation in environmental and human samples
Molecular features of Hepatitis E Virus circulation in environmental and human samples
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DOI：
10.1016/j.jcv.2018.04.003
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发表时间：
2018-06-01
影响因子：
8.8
通讯作者：
Schvoerer, E.
中科院分区：
文献类型：
--
作者：
Fenaux, H.;Chassaing, M.;Schvoerer, E.
背景和目的：戊型肝炎病毒（HEV）正在出现，但其在人类和环境之间的传播仍然被误解。HEV ORF2基因编码在病毒与表面相互作用中起关键作用的衣壳，ORF3产物参与病毒周期。我们的目的是研究ORF2和ORF3在患者和环境中适合HEV的分子特征。研究设计：在法国东北部收集了69例肝炎患者（血液/粪便）、20例城市污水、20例猪屠宰场污水、22头农场猪（粪便）和20头野猪（肝脏/粪便）的样本。采用ORF2/ORF3的ORF2 M区直接测序分析HEV菌株的系统发育和理化预测，采用超深度测序分析ORF2。结果：患者血液中有9.1%的hiv阳性，粪便中有23.1%的hiv阳性；25.0%的废水，75.0%的屠宰场，10.0%的猪肝，5.3%的粪便。这些菌株被归类为HEV基因3型。在ORF2中，HEV在准种内突出了一个同质的主要病毒变异，并且两个次要突变（D442G, V402A）的预测抗原性降低。在公猪中观察到ORF3基因81位的半胱氨酸特征。结论：在患者和动物、屠宰场流出物和废水中检测到HEV RNA基因3型。此外，ORF2 M区氨基酸的低变异性以及ORF2和ORF3的分子特征表明，HEV菌株可能具有关键特性。
Background and objectives: Hepatitis E virus (HEV) is emerging but its circulation between humans and the environment remains misunderstood. HEV ORF2 gene encodes the capsid playing a key role in viral interactions with surfaces, ORF3 products are involved in the viral cycle. Our aim was to study the molecular characteristics of ORF2 and ORF3 which could favor HEV fitness in patients and the environment.Study design: Samples from 69 patients with hepatitis (blood/stools), 20 urban wastewaters, 20 effluents of a pig slaughterhouse, 22 farm pigs (stools), 20 wild boars (liver/stools) were collected in North-Eastern France. HEV strains were analyzed by direct sequencing within the ORF2 M region, of ORF2/ORF3, for phylogeny and physicochemical prediction and for ORF2 by ultra-deep sequencing.Results: The results showed frequent HEV-positive samples: 9.1% of the patient bloods, 23.1% of their stools; 25.0% of wastewaters, 75.0% for the slaughterhouse, 10.0% of the boar livers, 5.3% of their stools. The strains were classified as HEV genotype 3. In ORF2, HEV highlighted one homogeneous major viral variant within quasispecies and a decrease in predicted antigenicity for two minor mutations (D442G, V402A). A cysteine signature at position 81 in ORF3 was observed in the boars.Conclusions: HEV RNA genotype 3 was detected in patients and in animals, in a slaughterhouse effluent and in wastewater. Moreover, the low variability of amino acids in the ORF2 M region and molecular features in ORF2 and ORF3 suggested that HEV strains could be advantageous for key properties.