COVID 19: a clue from innate immunity

Abstract

The recent COVID-19 pandemic has had a significant impact on our lives and has rapidly expanded to reach more than 4 million cases worldwide by May 2020. These cases are characterized by extreme variability, from a mild or asymptomatic form lasting for a few days up to severe forms of interstitial pneumonia that may require ventilatory therapy and can lead to patient death.Several hypotheses have been drawn up to understand the role of the interaction between the infectious agent and the immune system in the development of the disease and the most severe forms; the role of the cytokine storm seems important.Innate immunity, as one of the first elements of guest interaction with different infectious agents, could play an important role in the development of the cytokine storm and be responsible for boosting more severe forms. Therefore, it seems important to study also this important arm of the immune system to adequately understand the pathogenesis of the disease. Research on this topic is also needed to develop therapeutic strategies for treatment of this disease.

Keywords: COVID-19; Coronavirus; Innate immunity; Interferon; SARS; TLR.

Fig. 1

Role of toll-like receptor in response to coronavirus infection. TLR4 is involved in the response triggered by oxidized phospholipids (OxPLs) induced by SARS-CoV2 infection, with activation, through MyD88 and TRIF, of the production of type I Interferon and inflammatory cytokines such as IL6 and TNF. TLR3 and TLR7/8 recognize viral RNA at the endosome and through MyD88 and TRIF, activate interferon regulatory factor (IRF3 and IRF7)