Total numbers of CD19⁺/CD20⁻/CD27^high plasmablasts/plasma cells do not consistently correlate with RA disease activity. Numbers of peripheral plasmablasts and plasma cells were plotted against RA disease activity index DAS28 at indicated time points. Each dot represents one patient. Except for 6 months after therapy, no significant correlation was detected between disease activity and plasmablast/plasma cell numbers (Spearman rank correlation analysis), suggesting that this peripheral cell population is not closely linked to disease activity. The first graph includes plasmablast/plasma cell numbers of 41 untreated healthy controls (HCs) for comparison.