The ORF8 protein of SARS-CoV-2 mediates immune evasion through down-regulating MHC-I

Cellular major histocompability complex class I (MHC-I) is down-regulated in SARS-CoV-2 infected cells, which is mediated by viral protein ORF8. This inhibition is not observed in the case of SARS-CoV ORF8, which may explain why there is a difference of pathogenesis between SARS-CoV and SARS-CoV-2. SARS-CoV-2 ORF8 directly interacts with MHC-I and leads it to lysosomal degradation.