IL10 and COVID-19: Key examples include the observation that patients with acute COVID-19 display an IL-6/IL-10 cytokine imbalance in response to Toll-like receptor activation [70], that allograft-tolerated liver transplant recipients have a higher proportion of IL-10 producing B cells compared to transplant-recipient controls [62], and that an expansion of IL-10-producing B cells in the periphery and within the tumour itself is associated with adverse outcomes in multiple cancers including breast, colorectal [47, 58] and gastric cancer [71].