Galectin-3 binding protein stimulated IL-6 expression is impeded by antibody intervention in SARS-CoV-2 susceptible cell lines.

COVID-19 is the global pandemic that affected our population in the past 2 years. Considerable research has been done to better understand the pathophysiology of this disease and to identify new therapeutic targets, especially for severe cases. Galectin-3 (Gal-3) is a receptor present at the surface of different cell types, namely epithelial and inflammatory cells, which has been described as a severity marker in COVID-19. The activation of Gal-3 through its binding protein (Gal-3BP) is directly linked to the production of pro-inflammatory cytokines that contribute for the cytokine storm (CS) observed in severe COVID-19 patients. Here, we show that D2, a recombinant fragment of the lectin-binding region of Gal-3BP was able to stimulate the expression of IL-6 in colon and lung epithelial cell lines in β-galactoside dependent manner. We further show that D2-induced IL-6 augmentation was reduced by the anti-Gal-3BP monoclonal antibody 1959. Our data confirm and extend prior findings of Gal-3BP mediated IL-6 induction, enlightening the potential of its antibody-mediated s blockage for the prevention and treatment of CS and severe disease in COVID-19 patients.