A comparison of assays used for the detection of antibodies to DNA

In this paper we will briefly compare four assyas in use in our institute for the measurement of antibodies to DNA: the anti- DNA ELISA, the PEG assay, the indirect immunofluorescence test on Crithidia luciliae and the Farr assay. Although with the use of sera from defined patients with systemic lupus erythematosus (SLE) quite good correlations were obtained between the various assays, these correlations were lost upon the use in routine screening of sera of undefined patients. It will be shown that the Farr assay has the highest specificity to systemic lupus erythematosus, whereas the ELISA and the PEG assay are the most sensitive methods. In its present form, however, the ELISA is not suited for the detection of IgM anti-DNA. Furthermore, this technique alone also detects DNA/-anti-DNA complexes present in sera or hybridoma culture supernatants.