The autoantigens used corresponded to serological markers of prominent autoimmune diseases: dsDNA, Sm, SmB histone, and U1snRNP A and C for SLE; U1snRNP 68-kDa for MCTD, SSA and SSB for Sjogren's syndrome; Scl-70 for scleroderma; CENP B for CREST syndrome; Jo1 for polymyositis; Pm-Scl 100 for the SSc/PM-DM overlaping syndrome; myeloperoxidase for systemic vasculitis; b2-glycoprotein I for antiphospholipid syndrome; and thyroid peroxidase for autoimmune thyroiditis. Following incubation with patient sera, arrays are incubates with a secondary antibody conjugated with horseradish peroxidase.