Excessive inflammatory responses contribute to the pathogenesis and lethality of highly pathogenic human coronaviruses,but the underlying mechanism remains unclear.In this study,the N proteins of highly pathogenic hum...Excessive inflammatory responses contribute to the pathogenesis and lethality of highly pathogenic human coronaviruses,but the underlying mechanism remains unclear.In this study,the N proteins of highly pathogenic human coronaviruses,including severe acute respiratory syndrome coronavirus(SARS-CoV),middle east respiratory syndrome coronavirus(MERS-CoV)and severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),were found to bind MASP-2,a key serine protease in the lectin pathway of complement activation,resulting in excessive complement activation by potentiating MBL-dependent MASP-2 activation,and the deposition of MASP-2,C4b,activated C3 and C5b-9.Aggravated inflammatory lung injury was observed in mice infected with adenovirus expressing the N protein.Complement hyperactivation was also observed in SARS-CoV-2-infected patients.Either blocking the N protein:MASP-2 interaction,MASP-2 depletion or suppressing complement activation can significantly alleviate N protein-induced complement hyperactivation and lung injury in vitro and in vivo.Altogether,these data suggested that complement suppression may represent a novel therapeutic approach for pneumonia induced by these highly pathogenic coronaviruses.展开更多
基金funded by the National Science and Technology Major Projects(2018ZX09711003-005-005 and 2018ZX09201017-007)the National Basic Research Program of China(2012CB518902).
文摘Excessive inflammatory responses contribute to the pathogenesis and lethality of highly pathogenic human coronaviruses,but the underlying mechanism remains unclear.In this study,the N proteins of highly pathogenic human coronaviruses,including severe acute respiratory syndrome coronavirus(SARS-CoV),middle east respiratory syndrome coronavirus(MERS-CoV)and severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),were found to bind MASP-2,a key serine protease in the lectin pathway of complement activation,resulting in excessive complement activation by potentiating MBL-dependent MASP-2 activation,and the deposition of MASP-2,C4b,activated C3 and C5b-9.Aggravated inflammatory lung injury was observed in mice infected with adenovirus expressing the N protein.Complement hyperactivation was also observed in SARS-CoV-2-infected patients.Either blocking the N protein:MASP-2 interaction,MASP-2 depletion or suppressing complement activation can significantly alleviate N protein-induced complement hyperactivation and lung injury in vitro and in vivo.Altogether,these data suggested that complement suppression may represent a novel therapeutic approach for pneumonia induced by these highly pathogenic coronaviruses.