CD19 and rheumatoid arthritis: There was no statistically significant difference in the % of peripheral blood B (CD19+, RA: 7.6 ± 4.0% vs. disease controls: 9.1 ± 4.7% vs. healthy controls: 8.7 ± 2.6%, p = NS) or T cells (CD3+, RA: 69.2 ± 10.1% vs. disease controls: 71.3 ± 8.8% vs. healthy controls: 69.5 ± 5.6%, p = NS) between RA patients and controls (Figures 1A,B).