Figure 1.

Treatment of BDF1 lupus mice with T cell-targeted NPs loaded with IL-2 associates with changes in the frequency of different B cell subsets. (A) Gating strategy for the identification of B cell subsets by flow cytometry. Costaining of CD19⁺ B cells with additional markers allowed the identification of transitional 1 (T1) B cells as CD24⁺IgM⁺CD21⁻, transitional 2 (T2) B cells as CD24⁺IgM⁺CD21^int/lo, follicular (FO) B cells as CD24^loIgM^loCD21^int, and marginal zone (MZ) B cells as CD24⁺IgM⁺CD21^hi. Percentages (B) and absolute numbers (C) of splenic B cell subsets from BDF1 lupus mice treated with T cell-targeted NPs loaded with IL-2 (red boxes) or non-targeted unloaded NPs (blue boxes). Data are at week 2 after treatment with NPs; n = 4–8 mice per group; *P < 0.04. NPs, nanoparticles.