特异性抑制 NLRP3 炎性小体可抑制免疫过度激活，并减轻小鼠的类 COVID-19 病理。

Specific inhibition of the NLRP3 inflammasome suppresses immune overactivation and alleviates COVID-19 like pathology in mice.

机构信息

Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Kunming National High-level Biosafety Research Center for Non-Human Primates, Center for Biosafety Mega-Science, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650107, China; National Resource Center for Non-Human Primates, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650107, China.

出版信息

EBioMedicine. 2022 Jan;75:103803. doi: 10.1016/j.ebiom.2021.103803. Epub 2021 Dec 31.

DOI:10.1016/j.ebiom.2021.103803

PMID:34979342

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8719059/

Abstract

BACKGROUND

The Coronavirus Disease 2019 (COVID-19) pandemic has been a great threat to global public health since 2020. Although the advance on vaccine development has been largely achieved, a strategy to alleviate immune overactivation in severe COVID-19 patients is still needed. The NLRP3 inflammasome is activated upon SARS-CoV-2 infection and associated with COVID-19 severity. However, the processes by which the NLRP3 inflammasome is involved in COVID-19 disease remain unclear.

METHODS

We infected THP-1 derived macrophages, NLRP3 knockout mice, and human ACE2 transgenic mice with live SARS-CoV-2 in Biosafety Level 3 (BSL-3) laboratory. We performed quantitative real-time PCR for targeted viral or host genes from SARS-CoV-2 infected mouse tissues, conducted histological or immunofluorescence analysis in SARS-CoV-2 infected mouse tissues. We also injected intranasally AAV-hACE2 or intraperitoneally NLRP3 inflammasome inhibitor MCC950 before SARS-CoV-2 infection in mice as indicated.

FINDINGS

We have provided multiple lines of evidence that the NLRP3 inflammasome plays an important role in the host immune response to SARS-CoV-2 invasion of the lungs. Inhibition of the NLRP3 inflammasome attenuated the release of COVID-19 related pro-inflammatory cytokines in cell cultures and mice. The severe pathology induced by SARS-CoV-2 in lung tissues was reduced in Nlrp3 mice compared to wild-type C57BL/6 mice. Finally, specific inhibition of the NLRP3 inflammasome by MCC950 alleviated excessive lung inflammation and thus COVID-19 like pathology in human ACE2 transgenic mice.

INTERPRETATION

Inflammatory activation induced by SARS-CoV-2 is an important stimulator of COVID-19 related immunopathology. Targeting the NLRP3 inflammasome is a promising immune intervention against severe COVID-19 disease.

FUNDING

This work was supported by grants from the Bureau of Frontier Sciences and Education, CAS (grant no. QYZDJ-SSW-SMC005 to Y.G.Y.), the key project of the CAS "Light of West China" Program (to D.Y.) and Yunnan Province (202001AS070023 to D.Y.).

摘要

背景

自 2020 年以来，2019 年冠状病毒病（COVID-19）大流行一直是全球公共卫生的巨大威胁。尽管疫苗开发取得了很大进展，但仍需要一种减轻重症 COVID-19 患者免疫过度激活的策略。NLRP3 炎性体在 SARS-CoV-2 感染时被激活，并与 COVID-19 的严重程度相关。然而，NLRP3 炎性体参与 COVID-19 疾病的过程仍不清楚。

方法

我们在三级生物安全实验室（BSL-3）中用活 SARS-CoV-2 感染 THP-1 衍生的巨噬细胞、NLRP3 敲除小鼠和人 ACE2 转基因小鼠。我们从 SARS-CoV-2 感染的小鼠组织中进行了针对病毒或宿主基因的实时定量 PCR，对 SARS-CoV-2 感染的小鼠组织进行了组织学或免疫荧光分析。我们还根据需要在感染 SARS-CoV-2 之前，通过鼻内注射 AAV-hACE2 或腹腔内注射 NLRP3 炎性体抑制剂 MCC950 对小鼠进行处理。

发现

我们提供了多条证据表明，NLRP3 炎性体在宿主对 SARS-CoV-2 入侵肺部的免疫反应中发挥重要作用。在细胞培养物和小鼠中，NLRP3 炎性体的抑制作用减弱了 COVID-19 相关促炎细胞因子的释放。与野生型 C57BL/6 小鼠相比，Nlrp3 小鼠肺部组织中由 SARS-CoV-2 引起的严重病理减少。最后，MCC950 对 NLRP3 炎性体的特异性抑制减轻了人类 ACE2 转基因小鼠中过度的肺部炎症和 COVID-19 样病理。