TNF and rheumatoid arthritis: Recently, some therapeutic alternatives for RA that target inflammatory cytokines, namely infliximab (anti-TNF-α antibody; [7–9]), etanercept (a recombinant TNF receptor fusion protein; [10]) and anakinra (a recombinant human IL-1 receptor antagonist; [11]) have shown promising results in clinical trials and have been approved for the treatment of RA.