Randazzo Walter, Costantini Veronica, Morantz Esther K, Vinjé Jan
Division of Viral Diseases, National Calicivirus Laboratory, Centers for Disease Control and Prevention, Atlanta, GA, United States.
Department of Microbiology and Ecology, University of Valencia, Valencia, Spain.
Front Microbiol. 2020 Aug 18;11:1917. doi: 10.3389/fmicb.2020.01917. eCollection 2020.
Human noroviruses are the leading cause of epidemic and sporadic acute gastroenteritis worldwide and the most common cause of foodborne illness in the United States. Several natural compounds, such as aged-green tea extract (aged-GTE), have been suggested as ingestible antiviral agents against human norovirus based on data using murine norovirus and feline calicivirus as surrogates. However, data showing their effectiveness against infectious human norovirus are lacking. We tested the activity of aged-GTE to inhibit human norovirus in a human intestinal enteroids (HIEs) model and Tulane virus in LLC-monkey kidney (LLC-MK2) cell culture. HIE monolayers pretreated with aged-GTE at different temperatures showed complete inhibition of human norovirus GII.4 replication at concentrations as low as 1.0 mg/ml for 37°C, 1.75 mg/ml for 21°C, and 2.5 mg/ml for 7°C. In contrast, a moderate decrease in Tulane virus infectivity of 0.85, 0.75, and 0.65 log TCID/ml was observed for 2.5 mg/ml aged-GTE at 37, 21, and 7°C, respectively. Our findings demonstrate that GTE could be an effective natural compound against human norovirus GII.4, while only minimally effective against Tulane virus.
人诺如病毒是全球流行性和散发性急性胃肠炎的主要病因，也是美国食源性疾病最常见的病因。基于以鼠诺如病毒和猫杯状病毒作为替代物的数据，几种天然化合物，如陈化绿茶提取物（aged-GTE），已被提议作为针对人诺如病毒的可摄入抗病毒剂。然而，缺乏显示它们对感染性人诺如病毒有效性的数据。我们在人肠道类器官（HIEs）模型中测试了aged-GTE抑制人诺如病毒的活性，并在LLC-猴肾（LLC-MK2）细胞培养中测试了其对图莱里病毒的活性。在不同温度下用aged-GTE预处理的HIE单层细胞，在37°C时低至1.0 mg/ml、21°C时1.75 mg/ml、7°C时2.5 mg/ml的浓度下，均可完全抑制人诺如病毒GII.4的复制。相比之下，在37、21和7°C下，2.5 mg/ml的aged-GTE分别使图莱里病毒的感染性适度降低0.85、0.75和0.65 log TCID/ml。我们的研究结果表明，GTE可能是一种针对人诺如病毒GII.4的有效天然化合物，而对图莱里病毒的效果则微乎其微。
