Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently the most significant public health threat worldwide. Patients with severe COVID-19 usually have pneumonia concomitant with local inflammation and sometimes a cytokine storm. Specific components of the SARS-CoV-2 virus trigger lung inflammation, and recruitment of immune cells to the lungs exacerbates this process, although much remains unknown about the pathogenesis of COVID-19. Our study of lung type II pneumocyte cells (A549) demonstrated that ORF7, an open reading frame (ORF) in the genome of SARS-CoV-2, induced the production of CCL2, a chemokine that promotes the chemotaxis of monocytes, and decreased the expression of IL-8, a chemokine that recruits neutrophils. A549 cells also had an increased level of IL-6. The results of our chemotaxis Transwell assay suggested that ORF7 augmented monocyte infiltration and reduced the number of neutrophils. We conclude that the ORF7 of SARS-CoV-2 may have specific effects on the immunological changes in tissues after infection. These results suggest that the functions of other ORFs of SARS-CoV-2 should also be comprehensively examined.
【초록키워드】 COVID-19, Neutrophils, Monocytes, SARS-CoV-2, Coronavirus disease 2019, Cytokine storm, coronavirus, severe COVID-19, Pneumonia, IL-6, Genome, Infection, lung, chemokine, Type II pneumocyte, monocyte, IL-8, recruitment, expression, function, A549, infiltration, Lung inflammation, Immune cell, acute respiratory syndrome, Frame, tissue, CCL2, pathogenesis of COVID-19, component, chemotaxis, Specific, local inflammation, public health threat, Cell, examined, caused, reduced, ORF, demonstrated, suggested, promote, exacerbate, A549 cell, immunological change, recruit, specific effect, the SARS-CoV-2 virus, 【제목키워드】 SARS-CoV-2, Effect,