title: Rheumatoid factor plaque-forming cells in rheumatoid synovial tissue.
abstract: Cells producing rheumatoid factor (RF) were readily detected in vitro by means of a haemolytic plaque assay system employing sheep erythrocytes (SRBC) sensitized with reduced and alkylated rabbit IgG anti-SRBC antibody as target cells. Rheumatoid factor-producing, plaque-forming cells (RF-PFC) were observed in all of the synovial tissue cell preparations from seropositive rheumatoid arthritis patients studied. The numbers of RF-PFC varied considerably without any direct correlation with serum titres of RF antibody activity. However, high numbers of RF-PFC were never found in patients with low rheumatoid factor titres whereas, high and low numbers of RF-PFC were found among the patients with high RF titres. Synovial tissue cell preparations from a group of seronegative patients, with only one exception, failed to exhibit RF-PFC.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000921:Antibody-Producing Cells / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D002452:Cell Count; D002648:Child; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D006462:Hemolytic Plaque Technique; D006801:Humans; D007074:Immunoglobulin G; D008297:Male; D008875:Middle Aged; D012217:Rheumatoid Factor / Q000032:analysis*; D013583:Synovial Membrane / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G; D012217:Rheumatoid Factor