Fig. 5: CD19^– PCs are derived from CD19⁺ PCs.

A UMAP plot (left) shows the predicted path of PC cell maturation analyzed by Monocle3⁴⁹ for PC clusters from Sle123 mice. Color coding indicates pseudotime. The graph (right) shows Cd19 expression by indicated clusters over pseudotime. B Experimental workflow. BM and spleen were collected from Sle123 mice for sorting CD19⁺ and CD19^– PCs. Sorted cells were then transferred into Rag^−/− mice (via i.v.) and analyzed 7 days later. As a control, some Rag^-/- mice were injected with PBS only. The experimental workflow was created with BioRender.com. C Representative FACS plots (left) show the frequency of total PCs at day 7 after adoptive transfer in BM and spleen of Rag^−/− mice which received PBS, sorted CD19⁺ or CD19^– PCs. The graphs show the frequency (top) and absolute number (bottom) of total PCs at day 7 after adoptive transfer in BM and spleen of Rag^−/− mice received PBS, sorted CD19⁺ or CD19^– PCs. D Representative FACS plots (top) show the frequency of CD19⁺ versus CD19^– PCs in total BM and splenic PCs from Rag^−/− mice which received either sorted CD19⁺ or CD19^– PCs. The corresponding graphs (bottom) show the frequency of CD19⁺ or CD19^– in BM and spleen from Rag^−/− mice which received either sorted CD19⁺ or CD19^– PCs at the time before compared with after transfer. The frequency of CD19⁺ and CD19^– PCs at the time before transfer were cell purity after sorting. Data show compilation of n = 6 mice/group (BM and Spleen) and n = 13 mice (Kidney) (A) and two independent experiments (n = 6 mice/group) (C, D). Groups were compared using two-tailed paired t test (D) (^∗p = 0.031). P values ≥ 0.05 are not shown. Data show mean ± SEM.