Figure 7. Immunopathogenesis of Coronavirus Disease 2019 (COVID-19): Current understanding of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced host immune response. SARS-CoV-2 targets cells through the viral structural spike (S) protein that binds to the angiotensin converting enzyme 2 (ACE2) receptor. The serine protease type 2 transmembrane serine proteas (TMPRSS2) in the host cell further promotes viral uptake by cleaving ACE2 and activating the SARS-CoV-2 S protein. In the early stage, viral copy numbers can be high in the lower respiratory tract. Inflammatory signaling molecules are released by infected cells and alveolar macrophages in addition to recruited T lymphocytes, monocytes, and neutrophils. In the late stage, pulmonary edema can fill the alveolar spaces with hyaline membrane formation, compatible with early phase acute respiratory distress syndrome : Analysis on the Dynamic Attributes of SARS-CoV-2 and COVID-19 : Science and Education Publishing

Figure 7. Immunopathogenesis of Coronavirus Disease 2019 (COVID-19): Current understanding of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced host immune response. SARS-CoV-2 targets cells through the viral structural spike (S) protein that binds to the angiotensin converting enzyme 2 (ACE2) receptor. The serine protease type 2 transmembrane serine proteas (TMPRSS2) in the host cell further promotes viral uptake by cleaving ACE2 and activating the SARS-CoV-2 S protein. In the early stage, viral copy numbers can be high in the lower respiratory tract. Inflammatory signaling molecules are released by infected cells and alveolar macrophages in addition to recruited T lymphocytes, monocytes, and neutrophils. In the late stage, pulmonary edema can fill the alveolar spaces with hyaline membrane formation, compatible with early phase acute respiratory distress syndrome

American Journal of Infectious Diseases and Microbiology. 2022, 10(1), 26-47 doi:10.12691/ajidm-10-1-5