Preferential use of lambda L chain in lamin B autoantibodies.
The generation of lamin B autoantibodies was examined in a patient with SLE. Lamin B autoantibodies in this individual's serum were almost entirely IgG1 lambda at the onset of the autoimmune response. There was no evidence of IgM to IgG class switching, and no apparent diversification of the autoantibody response over the next 2 yr. The kappa/lambda L chain ratio of the lamin B autoantibodies was 0.13 by ELISA, with a kappa/lambda ratio of 0.70 for the patient's total IgG. In contrast, anti-histone autoantibodies in the patient's serum contained primarily kappa L chain. The kappa/lambda L chain ratios of lamin B autoantibodies from sera of four other patients with SLE were also consistent with restricted heterogeneity of lamin autoantibodies. In two, lambda L chain predominated, and in two others, the lamin B autoantibodies contained predominantly kappa L chains. The restricted heterogeneity of lamin B autoantibodies could be related to targeting of a single immunodominant autoepitope, to the existence of a particular L chain gene or genes that preferentially undergo somatic mutation, leading to the production of lamin B reactive clones, or to a combination of both mechanisms.
Reeves
W H
WH
Laboratory of Cell Biology, Rockefeller University, New York 10021.
Ali
S A
SA
D000918:Antibody Specificity; D001323:Autoantibodies / Q000032:analysis / Q000096:biosynthesis* / Q000145:classification; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007132:Immunoglobulin Isotypes / Q000032:analysis / Q000096:biosynthesis; D007145:Immunoglobulin kappa-Chains / Q000032:analysis; D007146:Immunoglobulin lambda-Chains / Q000032:analysis*; D034921:Lamin Type B; D034882:Lamins; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D009687:Nuclear Proteins / Q000276:immunology*; D011487:Protein Conformation
D001323:Autoantibodies; D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; D034921:Lamin Type B; D034882:Lamins; D009687:Nuclear Proteins