SARS-CoV-2 induces neutrophil degranulation and differentiation into myeloid-derived suppressor cells associated with severe COVID-19

neutrophils to suppress autologous T cell proliferation in vitro. These results support a role for PMN-MDSCs in mediating severe COVID-19, and inhibition of PD-L1 represents a potential therapeutic strategy for enhancing the immune response in acute SARS-CoV-2 infection.