Fig. 1

Proportions of B cells and B cell subsets in patients with eRA and HD and the association between subsets and disease. A Gating strategy showing gating on PBMCs for lymphocytes, which were further gated for singlets and thereafter CD19⁺ B cells. CD19⁺ B cells were further divided into CD21⁺ and CD21⁻ cells. The CD21⁺ and CD21⁻ were gated on using a CD27 vs IgD strategy. B Proportion of CD19⁺ B cells of peripheral blood lymphocytes. C Proportion of CD21⁺ cells of CD19 ⁺ B cells. D Proportion of CD21⁻ cells of CD19 ⁺B cells. E Multivariate factor analysis: An OPLS-DA loading plot showing the association between the different B cell subsets (X-variables) and eRA patients and HD, respectively (Y-variables). X-variables represented by bars pointing in the same direction as a Y-variable are positively associated with that Y-variable, whereas X-variables pointing the opposite direction are negatively related to that Y-variable. R2Y indicates how well the variation of Y is explained and Q2 how well Y can be predicted. F The proportion of the following B cell subsets: Naïve and transitional cells (NAV, CD27⁻IgD⁺), switched memory cells (SWM; CD27⁺IgD⁻), unswitched memory cells (USW, CD27⁺IgD⁺) and double-negative memory cells (DN, CD27⁻IgD⁻) of parent population CD21⁺ B cells. G The proportion of the following B cell subsets: naïve and transitional cells (NAV, CD27⁻IgD⁺), switched memory cells (SWM; CD27⁺IgD⁻), unswitched memory cells (USW, CD27⁺IgD⁺ and double-negative memory cells (DN, CD27⁻IgD⁻) of parent population CD21^−/low B cells. Mann–Whitney U test was used for statistical comparisons. *** p < 0.001, ****p < 0.0001. Between 1.5 × 10⁵ and 7 × 10⁶ events were recorded per sample. HD, healthy donors; eRA, early rheumatoid arthritis