Hidden rheumatoid factor and Wa idiotype expression in juvenile rheumatoid arthritis.
The major rheumatoid factor cross-reactive idiotype, which was defined by prototypic monoclonal IgM rheumatoid factors from Waldenstrom's macroglobulinaemia patient Wa, is present on 60% of all monoclonal IgM RF paraproteins. One-third of patients with juvenile rheumatoid arthritis (JRA), who are seronegative for classic IgM rheumatoid factor (RF), express the Wa idiotype in high titre in their sera. To determine if the Wa idiotype is present on hidden rheumatoid factors in JRA patient sera, we studied hidden RF expression by both ELISA and haemolytic assay techniques. The majority of JRA sera with increased concentrations of the Wa idiotype did not have increased RF activity nor hidden RF activity. In some JRA patients, the Wa idiotype may be expressed on a parallel set of immunoglobulin molecules, related to RFs, but lacking the ability to bind to IgG.
Department of Pediatrics, Schneider Childrens Hospital, New Hyde Park, NY 11042.
N T
NT
Ilowite
J F
JF
Wedgwood
T L
TL
Moore
T
T
Ramakrishnan
V R
VR
Bonagura
D000293:Adolescent; D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal; D000974:Antibodies, Antinuclear / Q000096:biosynthesis; D001171:Arthritis, Juvenile / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D002850:Chromatography, Gel; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015870:Gene Expression; D006462:Hemolytic Plaque Technique; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007130:Immunoglobulin Idiotypes / Q000032:analysis*; D007075:Immunoglobulin M / Q000032:analysis; D007223:Infant; D008297:Male; D011241:Prednisone / Q000627:therapeutic use; D012217:Rheumatoid Factor / Q000096:biosynthesis / Q000276:immunology*; D008258:Waldenstrom Macroglobulinemia / Q000276:immunology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D000974:Antibodies, Antinuclear; D007074:Immunoglobulin G; D007130:Immunoglobulin Idiotypes; D007075:Immunoglobulin M; D012217:Rheumatoid Factor; D011241:Prednisone