Fig. 1

Transitional and PD-1⁺ B cells in eRA patients at diagnosis and association with 24-week remission. (A) OPLS-DA loading plot of the association between B-cell subset frequencies at diagnosis (X–variables) and remission status after 24 weeks of treatment (binary Y-variables). (B) Frequency of transitional B cells (CD24⁺⁺CD38⁺⁺; in total B cells) in HC (N = 28) and eRA patients (N = 69) at diagnosis, Mann-Whitney U-test. (C) Frequency of PD-1⁺ B cells (of parent population CD21⁻ B cells) in HC (N = 27) and in eRA patients (N = 70) at diagnosis, unpaired T-test. (D) Frequency of transitional B cells in eRA patients at diagnosis, subdivided by 24-week follow-up remission status, unpaired T-test. (E) Frequency of CD21⁻ PD-1⁺ B cell, in eRA patients at diagnosis, subdivided by 24-week follow-up remission status, unpaired T-test. (F) Scatter plot and Spearman’s Rank correlation analyses of transitional B-cell frequency at diagnosis against 24-week follow-up CDAI. (G) Scatter plot and Spearman’s Rank correlation analyses of CD21⁻ PD-1⁺ B-cell frequency at diagnosis against 24-week follow-up CDAI. (E) ROC curves plotting individual regression models of transitional and CD21⁻ PD-1⁺ B-cell frequencies at diagnosis (dashed and dotted lines, respectively) or combined in one multiple regression model (black line). In panel B, the horizontal line indicates the median value, while in panels C– E horizontal lines indicate the mean values. ** p < 0.01. DN: Double Negative; Trans: Transitional; Pb: Plasmablast; Sw: Switched; Nav: Naive; Unsw: Unswitched; ns: non-significant; HC: Healthy Control; eRA: early Rheumatoid Arthritis; Rem: Remission; CDAI: Clinical Disease Activity Index; ROC: Receiver Operating Characteristic; AUC: Area Under the Curve; CI: 95 percent confidence interval; PPV: Positive Predictive Value; NPV: Negative Predictive Value