Fig. 5.

Size of synovial fluid B and T lymphocytes in comparison with peripheral blood (PB) cells. Mean forward scatters of lymphocytes expressing either CD19 (a) or CD4 or CD8 (b) were calculated. (a) Peripheral blood and synovial B cells from rheumatoid arthritis (RA) patients (□ and ▪, respectively) and reactive arthritis (ReA) patients (○ and Δ, respectively) are depicted. (b) Mean forward scatter from RA patients' CD4⁺ and CD8⁺ T cells from PB (□ and ○) and synovial fluid (▪ and Δ, respectively) display the same average.