ENA Profile ELISA Assay Kit is based on the absorptive immobilization of extractable nuclear Antigenss (native, recombinant and peptidic) to microtiter strips and subsequent binding of the ENA-antibodies. The bound antibodies are detected with a peroxidase-labelled secondary antibody that is directed against human IgG. After addition of substrate solution, a color appears which intensity is proportional to the concentration and/or the avidity of the detected antibodies. Following the addition of stop solution, the color switches from blue to yellow. Sample Types: serum, plasma. Range: Cut-off. Sensitivity: Cut-off. Time: 1.5 hours ? Antibodies to extractable nuclear Antigenss are characteristic for some rheumatic diseases and can contribute to the diagnosis and prognosis of systemic lupus erythematosus (SLE), Sjoegren's syndrome, mixed-connective tissue disease (MCTD), scleroderma, poly- and dermatomyositis and CREST syndrome.