"The present enzyme-linked immuno sorbent assay (ELISA) is intended for the quantitative or qualitative determination of IgG antibodies directed against dsDNA in human serum or plasma. The immobilised antigen is a highly purified preparation of plasmid dsDNA (90% in supercoiled state ) free from chromosomal DNA and protein (histones). The test is fast (incubation time 30/ 30/30 minutes) and flexible (divisible solid phase, ready-lo-use reagents). Six calibrators allow quantitative measurements; a negative and a positive control check the assay performance."