Fig 5. Constitutive Bcl-3 expression restricts CD8⁺ T cell terminal differentiation and supports formation of MPECs.

(A-G) Bcl3 Tg CD4 Cre and Bcl3 Tg (control) mice were infected with LCMV Armstrong, and spleens were analyzed 8 d p.i. (A) Graphs show proportions (left) and absolute numbers (right) of H-2D^b-GP33⁺ CD8⁺ T cells. Proportions (left panels) and absolute number (right panels) of IFN-γ (B) and IFN-γ + TNF-α (C) producing CD8⁺ T cells upon GP33 peptide stimulation ex vivo. (D) Representative contour plots show proportions of SLEC and MPEC cells among H-D^b-GP33⁺ CD8⁺ T cells in spleen with surface markers as indicated. (E) Graphs summarize proportions of SLEC (left panel) and MPEC (right panel) subsets on H-D^b-GP33⁺ CD8⁺ T cells as shown in (D). (F) Relative percentages of IFN-γ producing cells among H-D^b-GP33⁺ CD8⁺ T cells. (G) Proportion of TNF-α producing cells among IFN-γ⁺ CD8⁺ T cells upon GP33 peptide stimulation ex vivo. Data are summarized from three independent experiments with n = 13–18 mice for each genotype. Error bars indicate SEM. *p<0.05, ***p<0.001, ****p<0.0001.