Use of a new fluorescence immunoassay to detect anti-dsDNA antibodies is more correlated with disease activity and complement than the ELISA method in SLE patients

Abstract

To determine whether the serum levels of anti-double strand DNA (anti-dsDNA) autoantibodies detected using a newly developed fluorescence immunoassay (FIA) in patients with systemic lupus erythematosus (SLE) correlated more with clinical parameters, such as SLE disease activity index (SLEDAI), complement and the occurrence of nephritis when compared with traditional enzyme-linked immunosorbent assay (ELISA), we prospectively collected 124 serum samples from 31 patients who had juvenile-onset SLE and were regularly monitored every 2 months at our outpatient clinic. At every visit, clinical manifestations and laboratory parameters were assessed and the SLEDAI was determined. Correlation analyses between the two different measurements of anti-dsDNA antibodies and SLEDAI, serum complement levels and the occurrence of nephritis were performed. The results showed that anti-dsDNA autoantibodies detected using both ELISA and FIA significantly correlated with SLEDAI, and significantly and inversely correlated with the serum levels of C3 and C4. FIA had significantly higher correlation with SLEDAI and C4 than did ELISA. The mean values of anti-dsDNA antibodies detected using FIA in patients with nephritis were significantly higher than in those without nephritis. In contrast, the values of anti-dsDNA antibodies detected using ELISA did not show significant differences between these two groups. We conclude that FIA had better correlation with SLEDAI, C4 and the occurrence of nephritis, and comparable correlations with C3 that were similar to the results found using ELISA. Thus, it is worthwhile developing the FIA method for clinical evaluation of disease activity in SLE patients.

Anti-dsDNA antibody subtypes and anti-C1q antibodies: toward a more reliable diagnosis and monitoring of systemic lupus erythematosus and lupus nephritis

“…20 Whereas both assays show the lowest specificity for lupus nephritis (54%), assay 1 has a better specificity for the whole SLE group. Assay 4 is a relatively new automated method, extensively studied in the last three years [21][22][23][24] mainly because of its putative ability to detect preferentially high avidity aDNA-Ab. In agreement with our data, most studies revealed sensitivities for SLE between 40 and 64%, combined with specificities usually Ͼ90%.…”

“…In agreement with our data, most studies revealed sensitivities for SLE between 40 and 64%, combined with specificities usually Ͼ90%. [21][22][23][24] However, employing a special method to measure the Ab avidity directly 25 it could be shown, that only 45% of the aDNA-Ab detected by assay 4 represent really high avidity ones. 21 This could be in agreement with our observation, that the specificity, PPV and NPV for lupus nephritis are not remarkable higher than those found for assay 1.…”

Anti-dsDNA antibodies bind to TLR4 and activate NLRP3 inflammasome in lupus monocytes/macrophages

“…Anti-double stranded DNA (anti-dsDNA) antibodies are the hallmark antibodies of SLE [ 12 ]. Anti-dsDNA antibodies are correlated with disease activity [ 13 ] and involved in the pathogenesis of SLE [ 14 ]. Anti-dsDNA antibodies presented in the blood before disease onset [ 15 ] and administration of anti-dsDNA antibodies from SLE patients into NZBWF1/J mice resulted in accelerated lupus [ 16 ].…”

Clinical disease activity and titers of anti-dsDNA antibodies measured by an automated immunofluorescence assay in patients with systemic lupus erythematosus

“…4 -6 The latter characteristic is crucial for using it as a screening assay. However, utility for detecting lupus flares had not previously been demonstrated, except in one recent work by Chen et al, 12 where they studied 31 patients with juvenile-onset SLE.…”