Individual and combinatorial contribution of type I, II and III interferons in limiting SARS-CoV-2 replication, disease progression and age-related mortality [RN21189]

Using a mouse-adapted SARS-CoV-2 variant (SARS-CoV-2 MA20), newly generated in our lab, 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 C57BL/6 wild-type mice mice were either mock infected or infected with 300 PFU SARS‐CoV‐2 MA20 in a 40 μl volume. Lungs were harvested at 3, 4 and 5 days post infection.