TRIM21 and Sjogren syndrome: Primary Sjögren syndrome (PSS) is a chronic, autoimmune, and lymphoproliferative disease of the connective tissue characterized by development of lacrimal and salivary glands dysfunction due to lymphocytic infiltration of the exocrine glands.1 High serum levels of anti-SSA/Ro autoantibody, whose main target is autoantigen Ro52, are characteristic of PSS.2 However, similar to other autoantibodies shown to be associated with PSS, the role of these autoantibodies in the pathogenesis of the disease is unclear.