Two distinct immunopathological profiles in autopsy lungs of COVID-19

Coronavirus Disease 19 (COVID-19) is a respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has grown to a worldwide pandemic with substantial mortality. Immune mediated damage has been proposed as a pathogenic factor, but immune responses in lungs of COVID-19 patients remain poorly characterized. Here we show transcriptomic, histologic and cellular profiles of post mortem COVID-19 (n=34 tissues from 16 patients) and normal lung tissues (n=9 tissues from 6 patients). Two distinct immunopathological reaction patterns of lethal COVID-19 are identified. One pattern shows high local expression of interferon stimulated genes (ISG(high)) and cytokines, high viral loads and limited pulmonary damage, the other pattern shows severely damaged lungs, low ISGs (ISG(low)), low viral loads and abundant infiltrating activated CD8(+) T cells and macrophages. ISG(high) patients die significantly earlier after hospitalization than ISG(low) patients. Our study may point to distinct stages of progression of COVID-19 lung disease and highlights the need for peripheral blood biomarkers that inform about patient lung status and guide treatment. The immunopathological features of SARS-CoV-2 infection in the lungs remain unclear. Here, the authors provide a comprehensive characterization of post mortem lung tissues of COVID-19 patients and find two distinct patterns characterized by differential expression of interferon stimulated genes (ISGs), which correlate to viral loads, cytokines, lung damage and time of hospitalization, suggesting ISG profiles to mark disease progression