SGCG and infection: It should be noted, however, that in ex vivo comparisons of SARS-CoV-2 and SARS-CoV infection in human lung tissues, although SARS-CoV-2 infected both type I and type II pneumocytes and alveolar macrophages and replicated more efficiently than SARS-CoV, SASR-CoV infection resulted in higher levels of type I, type II, and type III IFN responses than SASR-CoV-2 infection [59].