Mononuclear phagocyte system Fc-receptor function in patients with seropositive rheumatoid arthritis

• Published in: Clinical and experimental immunology Vol. 67; no. 3; pp. 461 - 466
• Main Authors: LOBATTO, S, BREEDVELD, F. C, CAMPS, J. A. J, PAUWELS, E. K. J, WESTEDT, M.-L, DAHA, M. R, VAN ES, L. A
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell 01-03-1987
• Subjects: Adult; Aged; Antigen-Antibody Complex - analysis; Arthritis, Rheumatoid - drug therapy; Arthritis, Rheumatoid - immunology; Biological and medical sciences; Diseases of the osteoarticular system; Erythrocytes - immunology; Female; Humans; Immunoglobulin G - metabolism; Inflammatory joint diseases; Isoantibodies - physiology; Liver - immunology; Male; Medical sciences; Middle Aged; Phagocytes - immunology; Receptors, Fc - immunology; Rh-Hr Blood-Group System - immunology; Spleen - immunology; Human; Chronic; Immunology; Mononuclear cell; Fc-Fragment; Rheumatoid arthritis; Diseases of the osteoarticular system; Inflammatory joint disease; Phagocyte; Biological receptor
• ISSN: 0009-9104; 1365-2249

Mononuclear phagocyte system (MPS) Fc-receptor function in 20 patients with seropositive rheumatoid arthritis (RA) was investigated using radiolabelled autologous erythrocytes coated with an average of 5,800 molecules of anti-rhesus IgG (E. IgG). Although clearance times (T1/2) of E. IgG tended to be longer in RA patients than those in healthy controls (46 +/- 6 min vs 38 +/- 5 min, mean +/- s.e.m., P = 0.38), this did not reach statistical significance. Liver spleen uptake ratios (LS ratios) were increased in patients with RA (13/100 +/- 1/100 vs 7/100 +/- 1/100, P less than 0.05). There was no correlation of T1/2 or LS ratios with articular disease activity, vasculitis, ESR, IgM containing immune complex levels or Clq-binding immune complex levels. Although Clq-binding immune complex levels were significantly higher in patients with vasculitis than in those without (P less than 0.01), T1/2 and LS ratios did not differ in these two groups of patients. The T1/2 and LS ratios of E.IgG did not reveal a defect in MPS Fc-receptor function and did not correlate with one of the above-mentioned clinical and immunological parameters. We suggest that in order to establish a possible defect in Fc-receptor function correlating with disease activity and immune complex levels in RA patients, soluble immune complexes or immune complex-like material should be used as probes.