Figure 1  .

Density of β₂ adrenergic receptors (β2R) on CD19+ lymphocytes. The density of β2R on CD19+ cells is significantly reduced in patients with chronic rheumatic diseases (rheumatoid arthritis (RA, n=24), systemic lupus erythematosus (SLE, n=13), systemic sclerosis (SSc, n=6) compared with healthy control subjects (controls, n=16) (p<0.001; one way analysis of variance followed by Tukey's procedure; RA, SLE, or SSc v controls). No significant difference is seen between the three patient groups. Data are presented as plots of the receptor numbers of individual subjects, the bar representing the mean.