IL6 and COVID-19: Severe COVID-19 patients exhibit high level of pro-inflammatory macrophages, neutrophils and monocytes, which contribute to the cytokine storm with very high plasma levels of TNF, IL-12, IL-6, IL-10, IL-7, G-CSF, IP-10, MIP1α, and MCP1 (Chen et al., 2020; Liao et al., 2020; Zhou et al., 2020).