Early alveolar epithelial cell necrosis is a potential driver of COVID-19-induced acute respiratory distress syndrome
Kentaro Tojo,
Natsuhiro Yamamoto,
Nao Tamada,
Takahiro Mihara,
Miyo Abe,
Mototsugu Nishii,
Ichiro Takeuchi,
Takahisa Goto
Affiliations
Kentaro Tojo
Department of Anesthesiology and Critical Care Medicine, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan; Corresponding author
Natsuhiro Yamamoto
Department of Anesthesiology and Critical Care Medicine, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan
Nao Tamada
Department of Anesthesiology and Critical Care Medicine, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan; Department of Paramedic, Kyorin University Faculty of Health Sciences, Mitaka, Tokyo, Japan
Takahiro Mihara
Department of Health Data Science, Yokohama City University Graduate School of Data Science, Yokohama, Kanagawa, Japan
Miyo Abe
Department of Anesthesiology and Critical Care Medicine, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan
Mototsugu Nishii
Department of Emergency Medicine, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan
Ichiro Takeuchi
Department of Emergency Medicine, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan
Takahisa Goto
Department of Anesthesiology and Critical Care Medicine, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan
Summary: Acute respiratory distress syndrome (ARDS) with COVID-19 is aggravated by hyperinflammatory responses even after the peak of the viral load has passed; however, its underlying mechanisms remain unclear. In the present study, analysis of the alveolar tissue injury markers and epithelial cell death markers in patients with COVID-19 revealed that COVID-19-induced ARDS was characterized by alveolar epithelial necrosis at an early disease stage. Serum levels of HMGB-1, one of the DAMPs released from necrotic cells, were also significantly elevated in these patients. Further analysis using a mouse model mimicking COVID-19-induced ARDS showed that the alveolar epithelial cell necrosis involved two forms of programmed necrosis, namely necroptosis, and pyroptosis. Finally, the neutralization of HMGB-1 attenuated alveolar tissue injury in the mouse model. Collectively, necrosis, including necroptosis and pyroptosis, is the predominant form of alveolar epithelial cell death at an early disease stage and subsequent release of DAMPs is a potential driver of COVID-19-induced ARDS.
