The SARS-CoV (Beijing strain, PUMC01 isolate) used in this study was provided by Z. Wang and Y. Liu (Chinese Academy of Medical Sciences, Chinese National Human Genome Center). All mouse studies were approved by the Ministry of Health Science and Technology division of the People's Republic of China. We intranasally inoculated mice with 100 μl virus (105.23 TCID50). At day 2, mice were killed, and the lungs were removed for further analyses. We assessed lung injury scores as described previously30 (link).