Figure 6.

p53 ablation does not rectify the defective T_FH generation in Ddb1-TaKO mice. (A) Flow cytometry of activated (CD44^hi) CD4⁺ T cells from WT, Ddb1-TaKO, and Ddb1^fl/fl Trp53^fl/fl OX40-cre (Ddb1/p53-DTaKO) mice at day 8 day after LCMV Armstrong infection. Numbers adjacent to outlined areas indicate percentage of CXCR5⁺ SLAM^lo polyclonal T_FH cells (top row) or CXCR5⁺ PD1⁺ GC T_FH cells (middle row) or CXCR5⁺ Bcl-6⁺ GC T_FH cells (bottom row). (B) Frequency and total number of T_FH cells and GC T_FH cells in the spleen of mice as in (A) (n = 5). (C) Flow cytometry of total B220⁺ B cells from mice as in (A) Number adjacent to outlined areas indicate percentage of GC B and plasma cells. (D) Frequency and total number of GC B and plasma cells in the spleen of mice as in (A) (n = 5). Each symbol represents an individual mouse, small horizontal lines indicate the mean ( ± s.d.). **P < 0.01; ***P < 0.001; ****P < 0.0001 (Student’s unpaired t-test). Data are representative of three independent experiments (error bars, s.d.).