Expression of an interspecies idiotype in sera of SLE patients and their first-degree relatives.
Sera from 29 SLE patients and 81 first-degree healthy family members were tested for quantitative expression of a cross-reactive idiotype present on a murine monoclonal anti-Sm autoantibody (Y2). Forty-one percent of SLE patients and 27% of all relatives showed increased serum levels of the Y2 idiotype compared to 6% in a normal, unrelated control group. In addition, female relatives of SLE patients showed slightly increased levels of anti-Sm antibodies compared to male relatives (15% vs 3%). In one of the 28 families and three unrelated SLE patients studied, there was a significant correlation between the Y2 idiotype expression and expression of another idiotype present on anti-DNA antibodies (1341d). Affinity column absorption studies showed that these two idiotypes were present on different antibody molecules. This study demonstrates: (1) a genetic predisposition for an anti-Sm antibody idiotype expression in humans; and (2) that two different idiotypes may be under parallel or coordinate regulation.
Dang
H
H
Department of Medicine, University of Texas Health Science Center, San Antonio 78284-7874.
Takei
M
M
Isenberg
D
D
Shoenfeld
Y
Y
Backimer
R
R
Rauch
J
J
Talal
N
N
D000974:Antibodies, Antinuclear / Q000276:immunology; D001323:Autoantibodies / Q000032:analysis*; D001324:Autoantigens / Q000276:immunology; D005260:Female; D006801:Humans; D007130:Immunoglobulin Idiotypes / Q000032:analysis*; D007136:Immunoglobulins / Q000032:analysis; D008180:Lupus Erythematosus, Systemic / Q000235:genetics / Q000276:immunology*; D008297:Male; D012261:Ribonucleoproteins / Q000276:immunology; D017411:Ribonucleoproteins, Small Nuclear; D012737:Sex Factors; D055517:snRNP Core Proteins
D000974:Antibodies, Antinuclear; D001323:Autoantibodies; D001324:Autoantigens; D007130:Immunoglobulin Idiotypes; D007136:Immunoglobulins; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D055517:snRNP Core Proteins