Targeting ADAM‐17 to Alleviate Cytokine Storm Associated with COVID‐19

Abstract

Background Acute respiratory distress syndrome (ARDS) is the primary cause of mortality in critically ill subjects infected with the novel coronavirus (severe acute respiratory syndrome‐coronavirus‐2, or SARS‐CoV‐2). Given the elevated levels of circulating proinflammatory cytokines such as tumor necrosis factors (TNF)‐⍺ and interleukin (IL)‐6, it has been postulated that a “cytokine storm” is responsible for the COVID‐19 ARDS. A critical step in cytokine signaling is the shedding of membrane‐anchored cytokines and their receptors. Objective To determine the role of the metalloprotease/shreddase ADAM‐17 (A disinterring and metalloproteinase 17) in COVID‐19‐ mediated cytokine release from lung epithelial cells. We hypothesized pharmacological inhibition of ADAM‐17 attenuated COVID‐19‐induced release of TNF‐α in lung epithelial cells. Materials and Methods Human primary bronchial/tracheal epithelial cells (ATCC®, PS‐300‐010) were cultured to sub‐confluence and challenged with COVID‐19 Spike Coronavirus pseudovirus (SARS‐COV‐2 pseudo‐virus, MyBioSource), and phorbol‐12‐myristate‐13‐acetate (PMA, Sigma), which was used as a positive control in the presence or absence of the ADAM‐17 inhibitor TNF‐α Protease Inhibitor‐0 (TAPI‐0, Sigma). TNF‐α levels were determined in the cell media at different time points (2‐12h) following the challenge using an ELISA assay. Data are represented as mean ± SEM, and statistical significance was determined by using the Student’s t‐test. Results Treatment with both PMA (0.1 µM) and SARS‐COV‐2 pseudovirus (1x108pseudoviral particles), resulted in a robust increase of TNF‐α in the culture media 8 h post‐stimulation (3243.75± 55.3 and 1278.6 ± 357 pg/mL respectively, p <0.05, n = 4). Furthermore, treatment with TAPI‐0 resulted in a concentration‐dependent inhibition of the pseudovirus‐induced TNF‐α release by cultured bronchial epithelial cells, with a complete inhibition observed at 100 µM of TAPI‐0. Conclusion Targeting ADAM‐17 is a potential strategy to mitigated the cytokine storm associated with COVID‐19‐ARDS.