Figure 3

B cell phenotype distribution before rituximab. Frequencies of (a) CD27^- IgD^- double-negative B cells and (b) CD27⁺⁺ IgD^- plasmablast in patients with rheumatoid arthritis (RA) at baseline and in healthy age-matched controls. The percentages of CD38^hi cells within (c) the post-switch memory B cells and (d) plasmablasts (that is, late plasmablasts [16]) are shown. (e) The frequency of CD95⁺ cells within the pre-switch memory B cells is depicted. Significant differences between the populations using Mann-Whitney-test are indicated. Of note, the difference between non-responders and responders was significant using univariate logistic regression analysis.