Pro-inflammatory cytokines that promote or are secreted by T helper 1 (Th1) cells (IL-12, IFN-γ, TNF-α, IL-2) or Th17 cells (IL-23, IL-17, TNF-α, IL-22) often drive RA disease whereas cytokines secreted by Th2 cells (IL-4, IL-5, IL-10) and regulatory T (Treg) cells (TGF-β and IL-10) are anti-inflammatory and regulatory [4]. Here, TNF is linked to rheumatoid arthritis.