Individual and combinatorial contribution of type I, II and III interferons in limiting SARS-CoV-2 replication, disease progression and age-related mortality [RN21061]

Using a mouse-adapted SARS-CoV-2 variant (SARS-CoV-2 MA), we found that endogenous type I and type III IFNs synergize to limit SARS-CoV-2 replication and to expedite virus clearance and that enhanced disease progression in aged mice depends on impaired type II IFN immunity Adult 8‐12‐week‐old mice and aged 16‐24 week‐old Ifnar1‐/‐ mice on a C57BL/6 background, were either mock infected or infected with 10^5 PFU SARS‐CoV‐2 MA in a 40 μl volume. Lungs were harvested at 3 days post infection.