IL6 and infection: Furthermore, since IL-6 cis-signalling elicits host defence against pathogens and promotes the growth and survival of hepatocytes, megacaryocytes and intestinal epithelial cells (25, 26), membrane IL-6R blockade might promote adverse events and complications, including serious infections (e.g., ventilator-associated pneumonia) (37, 38), increased transaminases, thrombocytopenia and intestinal perforation, particularly in patients who are critically-ill with COVID-19, as they are intubated, immunosuppressed, and inflamed or hypoperfused at multiple levels.