Anti-DNA idiotypes deposited in renal glomeruli of patients with lupus nephritis.
Idiotypes (Id) of human anti-DNA antibodies, designated as O-81 Id, were specifically detected on the immune deposits of renal glomeruli in 46% of patients with lupus nephritis. Id-binding to anti-Id antibodies was blocked by free O-81 Id and to some extent by free DNA. DNase or acid buffer treatment failed to reveal new Id determinants on the deposits. O-81 Id and NE-1 Id activity were also detected on the renal eluate-derived IgG, but not IgM from the autopsy cases with lupus nephritis. The incidences of O-81 Id were not associated with histological features in the glomeruli, but the distribution patterns were similar to those of IgG deposits. Our study also showed that 65% to 70% of patients with IgG deposits either in the subendothelium or in the subepithelial area of the glomerular basement membrane (GBM) showed positive tests for O-81 Id. It was also noted that most patients with massive proteinuria had O-81 Id in their glomeruli. It is concluded that O-81 Id deposits are relatively specific for active lupus nephritis and that immunofluorescence studies using anti-Id antibodies may be clinically useful for specifying the renal lesions of systemic lupus erythematosus (SLE).
Suzuki
M
M
Second Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Hatakeyama
A
A
Kameoka
J
J
Tamate
E
E
Yusa
A
A
Kurosawa
K
K
Saito
T
T
Sasaki
T
T
Yoshinaga
K
K
D000888:Antibodies, Anti-Idiotypic / Q000302:isolation & purification*; D000974:Antibodies, Antinuclear / Q000302:isolation & purification*; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007677:Kidney Function Tests; D007678:Kidney Glomerulus / Q000276:immunology*; D008181:Lupus Nephritis / Q000276:immunology*; D008856:Microscopy, Fluorescence
D000888:Antibodies, Anti-Idiotypic; D000974:Antibodies, Antinuclear; D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G