摘要
To discover new drugs to combat COVID-19,an understanding of the molecular basis of SARS-CoV-2 infection is urgently needed.Here,for the first time,we report the crucial role of cathepsin L(CTSL)in patients with COVID-19.The circulating level of CTSL was elevated after SARS-CoV-2 infection and was positively correlated with disease course and severity.Correspondingly,SARS-CoV-2 pseudovirus infection increased CTSL expression in human cells in vitro and human ACE2 transgenic mice in vivo,while CTSL overexpression,in turn,enhanced pseudovirus infection in human cells.CTSL functionally cleaved the SARS-CoV-2 spike protein and enhanced virus entry,as evidenced by CTSL overexpression and knockdown in vitro and application of CTSL inhibitor drugs in vivo.Furthermore,amantadine,a licensed anti-influenza drug,significantly inhibited CTSL activity after SARS-CoV-2 pseudovirus infection and prevented infection both in vitro and in vivo.Therefore,CTSL is a promising target for new anti-COVID-19 drug development.
基金
This work was supported by grants from the National Key R&D Program of China(2017YFC0909600)
National Natural Science Foundation of China(81930019,8151101058,81471014)
Scientific Project of Beijing Municipal Science&Technology Commission(D171100002817005)
Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding Support(ZYLX201823)。
