Figure 2. Intrinsic NF-κB2 p100/p52 signaling restricts the peripheral Treg cell pool.

(A–C) Spleen and peripheral lymph nodes of 6–8 weeks-old Foxp3^cre and Foxp3^crenfkb2^F/F mice were stained for FACS. (A) Expression of Foxp3 in gated spleen TCR-β⁺CD4⁺ live cells. Numbers indicate the percentage in gate. (B) % in TCR-β⁺CD4⁺ and absolute numbers of Treg cells. (C) Expression of Foxp3 and pooled MFI in gated spleen TCR-B⁺CD4⁺Foxp3⁺ Treg cells. (D–F) The cell-intrinsic role of nfkb2 in Treg cells was evaluated in mixed BM chimeras. (D) Experimental design. (E) % of Treg cells in TCR-β⁺CD4⁺CD45.2⁺ cells. (F) Representative Ki67 expression in gated spleen in TCR-β⁺CD4⁺CD45.2⁺Foxp3⁺ Treg cells, and pooled % of Ki67⁺ in Treg cells. Numbers indicate the percentage in gate. (G) Expression of Nrp-1 and Helios in gated spleen in TCR-β⁺CD4⁺Foxp3⁺ Treg cells from Foxp3^cre and Foxp3^crenfkb2 ^F/F animals. (G) Naïve T cells from CD4^cre and CD4^crenfkb2 ^F/F LN were cultured under iTreg polarization conditions for 4 days. The % of Treg in each genotype in 3 experiments is shown. Data is representative (A, C, D–G) or the pool (B, H) of 2–3 experiments. In B, E and F, each dot represents a mouse. *p<0.05,** p<0.005, ***p<0.001.