Light chain ratios of serum immunoglobulins in disease.
We have determined the individual kappa (kappa)/lambda (lambda) ratios of serum IgG, IgA, and IgM in normal subjects and patients with rheumatoid arthritis, systemic lupus erythematosus, hepatic cirrhosis and IgA nephropathy--40 in each group. Serum samples were first screened by agarose electrophoresis to exclude paraproteinaemia. Concentrations of IgG, IgA, and IgM were determined by enzyme-linked immunosorbent assay (ELISA). The kappa and lambda chain concentrations of each immunoglobulin class were assayed by an ELISA method first developed by us for the determination of kappa/lambda ratios. Our results showed that kappa/lambda ratios of serum IgA and IgM were significantly different from that of IgG in normal subjects and the 4 groups of patients studied (p less than 0.01). The kappa/lambda ratios of individual immunoglobulins in patients with rheumatoid arthritis, systemic lupus erythematosus and liver cirrhosis were similar to those of normal subjects. However, patients with IgA nephropathy displayed a distinctly lower IgA kappa/lambda ratio, suggesting a unique antibody response in the immunopathogenesis of this disease.
Lam
C W
CW
Department of Chemical Pathology, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin.
Chui
S H
SH
Leung
N W
NW
Li
E K
EK
Lai
K N
KN
D000906:Antibodies; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D004587:Electrophoresis, Agar Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005922:Glomerulonephritis, IGA / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007147:Immunoglobulin Light Chains / Q000032:analysis*; D007075:Immunoglobulin M / Q000032:analysis; D007145:Immunoglobulin kappa-Chains / Q000032:analysis; D007146:Immunoglobulin lambda-Chains / Q000032:analysis; D008103:Liver Cirrhosis / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*
D000906:Antibodies; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007147:Immunoglobulin Light Chains; D007075:Immunoglobulin M; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains