Do you want to learn know how the innate immune system reacts to SARS-CoV-2? Keep reading thanks to @AliHackl and @lissi.heiter from @03Sp1 @UniFreiburg for this great thread! #onlineteaching #onlinelearning #COVID19

Circulating white blood cells (neutrophils and monocytes) and tissue resident cells (macrophages, mast cells and dendritic cells) are key cells of the innate immunity.

Cells of the innate immunity express innate immune receptors to recognise a variety of different pathogens via structures commonly present in microorganisms. These structures are called PAMPs (Pattern associated molecular patterns).

Upon recognition of the pathogen, the cells of the innate immune system perform different functions. Some cells ingest (phagocytose) and kill the pathogen, others secrete cytokines and chemokines to further activate the immune response.

The innate immune system is activated after the virus SARS-CoV-2, which causes COVID-19, replicates in the cells of the human respiratory tract. Damaged cells release interferons, cytokines and other molecules that activate the immune response.

The released molecules act on alveolar macrophages, which clear up neutralised virus and infected cells by secreting inflammatory cytokines and chemokines, which recruits circulating immune cells and enhanced vascular permeability.

Efficient innate immune response against viral infection rely greatly on one particular cytokine: Type I interferon.

However, viruses evade the immune responses. There is evidence suggesting that SARS-CoV-2 potentially shares immune evasions mechanisms used by SARS-CoV and MERS-CoV.

This highly efficient evasion mechanism together with the delayed interferon release might explain the increased severity of disease in some COVID-19 patients.

Do you wan to learn more about the innate immune system? Watch the videos that @CIBSS_UniFR prepared for the day of Immunology in #Youtube:

My apologies, I target one of the authors of this thread wrongly! This thread was made by @HeiterLissi and @AliHackl @03Sp1 , Thanks again for the amazing job!