Question

Can you identify an innate immune cell that responds to SARS-COV2 infection? What are mechanisms by which the cell facilitates clearance of the virus?

Answer 1

Dendritic cells and macrophages are first line components of the innate immune network. DCs, play important roles in driving both innate and adaptive immune responses to viral pathogens. Spiegel et al., also demonstrated that both live and UV inactivated SARS-CoV could induce type I IFN responses and cellular maturation in DC cultures suggesting that productive viral replication is not required to active anti-viral and/or pro-inflammatory responses in these cells.

Overall, many studies suggest that neither MPs nor DCs are highly permissive for SARS-CoV replication. While some groups did not see SARS-CoV associated inflammatory cytokine induction in MPs or DCs, the overall consensus from this work is that SARS-CoV infection can lead to either the direct activation or the priming of pro-inflammatory cytokine responses in these cell types, which may ultimately contribute to the development of virus-induced immune pathology within the lungs.