A quantitative ELISA for measurement of rheumatoid factor associated cross-reactive idiotypes in serum from patients with rheumatic diseases.
A sensitive ELISA for the quantitation of RF associated cross-reactive idiotypes (CRI) has been developed. CRI bearing IgM was captured by immobilized F(ab')2 fragments of monoclonal anti-CRI antibodies and revealed with isotype specific conjugates. Factors affecting sensitivity, specificity and reproducibility of the assay were assessed. The sensitivity limit was less than 10 ng/ml and the linear assay range for the CRI standard curve was from 80 to 500 ng/ml. Using this ELISA system we have quantitated serum levels of the CRI in different groups of patients with RA, early synovitis and normal individuals. Our results indicate a significant increase in the levels of the CRI in the patient groups compared to the normal subjects tested, and suggest involvement of a diverse repertoire of Ig variable region germline genes and/or somatic mutation in production of polyclonal RF in RA.
Shokri
F
F
Department of Immunology, Medical School, University of Birmingham, Edgbaston.
Mageed
R A
RA
Jefferis
R
R
D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005796:Genes; D006801:Humans; D007130:Immunoglobulin Idiotypes / Q000235:genetics / Q000276:immunology*; D015203:Reproducibility of Results; D012216:Rheumatic Diseases / Q000276:immunology*; D012217:Rheumatoid Factor / Q000032:analysis*; D012680:Sensitivity and Specificity
D007130:Immunoglobulin Idiotypes; D012217:Rheumatoid Factor