COMPARISON OF INDIRECT IMMUNOFLUORESCENCE ON CRITHIDIA-LUCILIAE, FARRASSAY AND NEW ELISA TECHNIQUES FOR THE DETECTION OF ANTI-NATIVE DNA ANTIBODIES

Anti-native DNA (ds DNA) antibodies were measured by the Farr assay, a n indirect immunofluorescence on Crithidia luciliae (IIFCL) and a newl y commercialised enzyme-linked immunosorbent assay (Elisa) in the sera of 270 patients: 73 negative controls, 67 patients with systemic lupu s erythematosus (SLE), 73 with clinical symptoms of another connective tissue disease and 61 patients with liver diseases. The Farr assay re mains a reliable method, IIFCL seems to be as specific but less sensit ive and Elisa has a higher sensitivity but a lower specificity. Finall y, 35 sera from the 270 patients were tested for anti-ds DNA antibodie s using two other commercialised Elisa-related techniques. The results suggest little correlation between the three Elisa methods.