Abatacept blocks anti-citrullinated protein antibody and rheumatoid factor mediated cytokine production in human macrophages in IDO-dependent manner

Background The anti-inflammatory effect of abatacept is most pronounced in patients with high-titer autoantibodies (including anticitrullinated protein antibodies [ACPA] and rheumatoid factor [RF]). Considering that autoantibodies trigger inflammatory cytokine production by monocytes and that abatacept binds to monocytes, influencing their functional state, we hypothesized that abatacept may effectively inhibit the production of several different cytokines by ACPA- or RF-challenged monocytes.