CALR and Down syndrome: Systemic lupus erythematosus (SLE) is a prototypic systemic autoimmune disease characterized by the persistent production of autoantibodies targeting diverse intracellular and cell-surface antigens, including antinuclear antibodies (ANA), anti-double-stranded DNA (anti-dsDNA), anti-Smith (Sm), anti-ribonucleoprotein (RNP), and antibodies to Sjögren’s syndrome-related antigens A (SSA/Ro) and B (SSB/La) (162, 163).