An analysis of clinical disease activity and nephritis-associated serum autoantibody profiles in patients with systemic lupus erythematosus: a cross-sectional study.

Abstract

To establish the correlation between lupus nephritis-associated autoantibody levels and the presence/activity of lupus nephritis and global disease activity using cross-sectional data in patients with systemic lupus erythematosus (SLE). Disease activity was assessed using the British Isles Lupus Assessment Group (BILAG) index. Antibody levels against single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), histones, nucleosomes and heparan sulphate (HS) were analysed by ELISA in SLE patients with (n=11) and without (n=22) nephritis and in normal controls (n=21). Antibody subclasses were also analysed. Higher levels of anti-dsDNA and anti-HS antibodies were found in patients with lupus nephritis, the level of anti-HS antibodies correlating with the BILAG renal score. Predominant subclasses were IgG1 and IgG3 for dsDNA antibodies, IgG2 for anti-nucleosome antibodies, and IgG2 and IgG3 for anti-HS antibodies. Correlation was demonstrated between antibodies to dsDNA, ssDNA, histones, nucleosomes and HS. There is a strong correlation between the level of anti-HS antibodies and disease activity in patients with lupus nephritis as measured by BILAG.