TRIM21 and systemic lupus erythematosus: Initially described as part of the Ro antigenic particle, Ro52 is among the first autoantigens discovered in systemic lupus erythematosus (SLE) (4, 5), a multisystemic autoimmune disease characterized by sustained IFN signaling and high-titer autoantibodies, leading to immune-mediated tissue damage (6, 7).