FCN1 and autoimmune disease: A subpopulation of macrophages positive for FCN1 was identified in patients with ABMR, FCN1 is involved in the pathogenesis of autoimmune diseases and targeting FCN1 is a promising strategy for the treatment of these diseases (Katayama et al., 2019), however, no studies have yet confirmed the role of FCN1 in renal transplant rejection.