ADORA2A and rheumatoid arthritis: Activation of A2AR inhibits NF-κB signaling pathway and inflammatory cytokine (IL-1, IL-6, TNF, IFN) production, and increases the anti-inflammatory cytokine IL-10 release, which leads to autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, or type 1 diabetes [34–36].