当前位置： SCI文献检索 > JOURNAL OF VIROLOGY期刊下所有文献 > A chimeric virus-mouse model system for evaluating the function and inhibition of papain-like proteases of emerging coronaviruses.

A chimeric virus-mouse model system for evaluating the function and inhibition of papain-like proteases of emerging coronaviruses.

Abstract：

:To combat emerging coronaviruses, developing safe and efficient platforms to evaluate viral protease activities and the efficacy of protease inhibitors is a high priority. Here, we exploit a biosafety level 2 (BSL-2) chimeric Sindbis virus system to evaluate protease activities and the efficacy of inhibitors directed against the papain-like protease (PLpro) of severe acute respiratory syndrome coronavirus (SARS-CoV), a biosafety level 3 (BSL-3) pathogen. We engineered Sindbis virus to coexpress PLpro and a substrate, murine interferon-stimulated gene 15 (ISG15), and found that PLpro mediates removal of ISG15 (deISGylation) from cellular proteins. Mutation of the catalytic cysteine residue of PLpro or addition of a PLpro inhibitor blocked deISGylation in virus-infected cells. Thus, deISGylation is a marker of PLpro activity. Infection of alpha/beta interferon receptor knockout (IFNAR(-/-)) mice with these chimeric viruses revealed that PLpro deISGylation activity removed ISG15-mediated protection during viral infection. Importantly, administration of a PLpro inhibitor protected these mice from lethal infection, demonstrating the efficacy of a coronavirus protease inhibitor in a mouse model. However, this PLpro inhibitor was not sufficient to protect the mice from lethal infection with SARS-CoV MA15, suggesting that further optimization of the delivery and stability of PLpro inhibitors is needed. We extended the chimeric-virus platform to evaluate the papain-like protease/deISGylating activity of Middle East respiratory syndrome coronavirus (MERS-CoV) to provide a small-animal model to evaluate PLpro inhibitors of this recently emerged pathogen. This platform has the potential to be universally adaptable to other viral and cellular enzymes that have deISGylating activities. Importance: Evaluating viral protease inhibitors in a small-animal model is a critical step in the path toward antiviral drug development. We modified a biosafety level 2 chimeric virus system to facilitate evaluation of inhibitors directed against highly pathogenic coronaviruses. We used this system to demonstrate the in vivo efficacy of an inhibitor of the papain-like protease of severe acute respiratory syndrome coronavirus. Furthermore, we demonstrate that the chimeric-virus system can be adapted to study the proteases of emerging human pathogens, such as Middle East respiratory syndrome coronavirus. This system provides an important tool to rapidly assess the efficacy of protease inhibitors targeting existing and emerging human pathogens, as well as other enzymes capable of removing ISG15 from cellular proteins.

journal_name

J Virol

journal_title

Journal of virology

authors

Deng X,Agnihothram S,Mielech AM,Nichols DB,Wilson MW,StJohn SE,Larsen SD,Mesecar AD,Lenschow DJ,Baric RS,Baker SC

doi

10.1128/JVI.01749-14

subject

Has Abstract

pub_date

2014-10-01 00:00:00

pages

11825-33

issue

eissn

0022-538X

issn

1098-5514

pii

JVI.01749-14

journal_volume

pub_type

杂志文章

在线工具

A chimeric virus-mouse model system for evaluating the function and inhibition of papain-like proteases of emerging coronaviruses.