IL6 and COVID-19: Interestingly, as observed in human COVID-19 patients with fatal disease (KO and 1A0) and those with severe disease (6A4) had overall, significantly increased systemic levels of G-CSF, IL-6, IL-10, TNF-α, IL-12 (p40), IL-17A, CCL5, and CCL11 compared to those with moderate disease (6A2 and 1A3) (55, 58, 59).