Are the clonotypes of serum IgG anti-DNA antibodies associated with lupus nephritis in humans?
We analyzed isoelectrofocusing (IEF) patterns of anti-DNA antibodies originated from sera and the renal eluates of patients with systemic lupus erythematosus (SLE). The spectrotypic patterns of serum anti-DNA-antibodies were heterogenous and bands with single-stranded (ss) and double-stranded (ds) DNA were detected in the PI 5.5-6.5 and 8-9.5 regions when SLE sera were tested, whereas healthy subjects failed to form bands even at different saline concentrations. No differences were found for IEF patterns of anti-DNA antibodies between patients with lupus nephritis and those without. The eluates from SLE glomeruli showed relatively restricted IEF patterns which were detected mainly in PI 6.0 and 8.5; but those from normal subject did not. These data indicate that anti-DNA antibodies will be responsible for the pathogenesis of lupus nephritis. Specific clonotypes of serum anti-DNA antibodies, however, could not be defined in an association with renal lesions of SLE. This study also suggests that the use of a high concentration of 6 M urea in an IEF analysis may be able to expose antigen-binding sites of the circulating immune complex (IC)-derived antibodies, leading to detection of specific antibodies in vivo-formed IC.
Hatakeyama
A
A
Second Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Sasaki
T
T
Muryoi
T
T
Murai
C
C
Yoshinaga
K
K
D000974:Antibodies, Antinuclear / Q000097:blood / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000097:blood / Q000276:immunology*; D000915:Antibody Affinity; D001402:B-Lymphocytes / Q000276:immunology; D002999:Clone Cells / Q000276:immunology; D004247:DNA / Q000276:immunology; D004277:DNA, Single-Stranded / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D007525:Isoelectric Focusing; D007668:Kidney / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D008181:Lupus Nephritis / Q000097:blood / Q000276:immunology*; D009994:Osmolar Concentration
D000974:Antibodies, Antinuclear; D000911:Antibodies, Monoclonal; D004277:DNA, Single-Stranded; D007074:Immunoglobulin G; D004247:DNA