Fig. 1

SARS-CoV-2 infects primarily alveolar cells through the ACE2 receptor. The immune system responds to the virus by activating different transcription factors that release pro-inflammatory cytokines that trigger the accumulation of immune cells leading to antigen presentation. Additionally, secretion of specific cytokines such as IL-8 attracts neutrophils and macrophages to the site of infection alongside T lymphocytes. While neutrophils kill by oxidative burst and NETs with macrophages inducing phagocytosis, CD4 + T cells help to activate B cells producing anti-SARS-CoV-2 and CD8 + T cells kill infected cells through the release of perforins and cytotoxins. If CD8 + T cells fail to kill the virus in the presence of inflammatory cytokines over the long term, cytokine storm occurs, leading to disease progression and complications such as ARDS, organ failure, and death