GADD34 is an inducible cofactor of protein phosphatase 1, which has an important role in the Unfolded Protein Response (UPR). UPR is a cellular response to ER stress which is implicated in several autoimmune diseases. GADD34 has been shown to be necessary for proinflammatory cytokine production in response to viral infection in murine models. Nevertheless, the role of GADD34 in cytokine production in humans remains to be elucidated. Here, we investigate the interest of GADD34 in rheumatoid arthritis (RA), in which proinflammatory cytokines have an important pathogenic role.