Adenosine receptor A2a blockade by caffeine increases IFN-gamma production in Th1 cells from patients with rheumatoid arthritis.

Studies indicate that caffeine uptake may be a risk factor for rheumatoid arthritis (RA), but a definitive link between caffeine consumption and RA has not been established. This study aimed to investigate the interplay between caffeine, adenosine receptor A2a, and interferon-γ (IFN-γ) production in CD4 Peripheral blood mononuclear cells were obtained from the peripheral blood of healthy individuals and patients with RA. CD4 Caffeine promoted IFN-γ production in Th1 cells in vitro. Significantly higher concentrations of caffeine were required to increase IFN-γ levels in Th1 cells from healthy individuals compared to Th1 cells from patients with RA. Moreover, ex vivo levels of adenosine receptor A2a expression on CD4 Caffeine promotes IFN-γ production in Th1 cells from RA patients in vitro by competitive inhibition of adenosine receptor A2a. Excessive coffee consumption could contribute to T-cell activation and inflammation in RA.