Mucins produced by type Ⅱ pneumocyte: culprits in SARS-CoV-2 pathogenesis  

作　　者：Bo Huang 

机构地区：[1]Department of Immunology&National Key Laboratory of Medical Molecular Biology,Institute of Basic Medical Sciences,Chinese Academy of Medical Sciences(CAMS)&Peking Union Medical College,Beijing,China [2]Department of Biochemistry&Molecular Biology,Tongji Medical College,Huazhong University of Science&Technology,Wuhan,China

出　　处：《Cellular & Molecular Immunology》2021年第7期1823-1825,共3页中国免疫学杂志（英文版）

基　　金：supported by the National Natural Science Foundation of China(81788101);Chinese Academy of Medical Sciences(CAMS)Initiative for Innovative Medicine(2020-l2M-CoV19-007).

摘　　要：The pandemic of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is sweeping across the world and has caused the loss of more than 3.3 million lives.Before clearance by virus-specific T and B cell-mediated adaptive immunity,excessive inflammation by innate immune cells might cause severe lung and even multiorganic pathologies,thus interfering with antiviral immunity.To curb infection and subsequent organic damage,a deep understanding of the pathogenetic process is highly desirable.Recently,we found that IFN-driven mucin expression in type Ⅱ alveolar epithelial cells is crucial in initiating hypoxia and early lung pathology1,and SARS-CoV-2 is disposed of by M1 and M2 alveolar macrophages(AMs)in distinct manners2.In this correspondence,we propose that(1)following the invasion of the alveoli and uptake by local alveolar macrophages,SARS-CoV-2 may stimulate macrophages to produce proinflammatory cytokines,including type Ⅰ interferon;(2)type I interferon acts on neighboring alveolar type Ⅱ pneumocytes and activates the cytoplasmic transcription factor aryl hydrocarbon receptor(AhR);(3)subsequently,AhR is translocated to the nucleus,where it promotes the expression of mucin genes,leading to mucus production;and(4)mucus begins to accumulate in the alveoli and gradually impairs the exchange of O2 and CO2,initially causing hypoxia and then dampening CO2 exhalation,leading to a critical illness.Here,we dissect these early pathogenic events,which might provide clues to interfering with SARS-CoV-2 infection at an early stage.

关 键 词：Alveolar macrophages Viral infection 

分 类 号：R563.1[医药卫生—呼吸系统]