title: Synovial fluid lymphocytes differ from peripheral blood lymphocytes in patients with rheumatoid arthritis.
abstract: Peripheral blood (PBL) and synovial fluid lymphocytes (SFL) from 12 patients with rheumatoid arthritis (RA) were analyzed using monoclonal antibodies that detect specific T cell surface antigens (OKT3, OKT4, OKT8, SC1) and antigens associated with lymphocyte activation (anti-Ia, OKT10, B3/25). RA patients' PBL contained 1010 +/- 74 OKT4+ and 401 +/- 62 OKT8+ cells/mm3 (ratio OKT4+/OKT8+ = 2.4 +/- 0.3). In contrast, SFL from these patients exhibited a significantly different proportion of T cell subsets (ratio OKT4+/OKT8+ = 1.1 +/- 0.5) (p less than 0.0001) with 630 +/- 180 OKT4+ and 595 +/- 225 OKT8+ cells/mm3. Synovial fluid contained significantly more activated T cells based on the presence of Ia-positive T cells (19 +/- 5%) and reactivity with antibody OKT10 (49 +/- 7%) compared with RA-PBL (8 +/- 3% Ia-positive T cells and 13 +/- 6% OKT10+). Compared with RA-PBL, normal PBL contained an elevated number of OKT8+ cells (610 +/- 48/mm3), a similar number of OKT4+ cells (1040 +/- 86/mm3), and a lower percentage of activated lymphocytes (3 +/- 2% Ia-positive T cells and 10 +/- 8% OKT10+ cells). SFL, RA-PBL, and normal PBL all showed less than 3% cells reactive with antibody B3/25 (anti-transferrin receptor antibody), a marker found on in vitro activated T cells. These findings demonstrate that the lymphocytes at the site of inflammation differ significantly from the lymphocytes present in the peripheral blood of the same patients. RA patients had a small but significant decrease in the number of OKT8+ cells/mm3 compared with normal PBL (p less than 0.01), suggesting that this lymphocyte subset may home to synovial tissues, where it becomes activated.
mesh_terms: D000911:Antibodies, Monoclonal; D000937:Antigen-Antibody Reactions; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001773:Blood Cells / Q000276:immunology*; D011232:Chemical Precipitation; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D013582:Synovial Fluid / Q000166:cytology* / Q000276:immunology; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000949:Histocompatibility Antigens Class II