IL6 and rheumatoid arthritis: Studies have demonstrated a pivotal role for inflammatory cytokines, including TNF-α, IL-1β, and IL-6, in RA initiation and progression (Benucci et al., 2012; do Prado et al., 2016; Duesterdieck-Zellmer et al., 2012; Furman et al., 2014; Giacomelli et al., 2016; Hreggvidsdottir et al., 2014; G.; Li et al., 2016).