Blocking α4 integrins enhances lymphoid tissue retention of stem-like CD8 ⁺ T cells. (A) Experimental design. Same P14 co-transfer and LCMV infection setup as in Fig. 1. On day 7 and 10 after infection, integrin α4 blocking antibody was administrated and examined on day 12. (B) Representative FACS profiles of splenic lymphocytes are shown. (C) The percentage of stem-like subset in P14 T cells located in red pulp (upper) and follicles (lower) is shown. (D) The percentage of Tcf-1⁺ (left) and Tcf-1⁻ (right) donor P14 T cells in total splenic CD8⁺ population is shown. (E) The percentage of CD69⁺ in Tcf-1⁺ and Tcf-1⁻ P14s is shown. (F–H) The percentage of granzyme A⁺ (F), IFN-γ⁺ (G), and IL-2⁺ (H) cells in Tcf-1⁺ and Tcf-1⁻ P14s is shown. Each pair of symbols in E–H, and each symbol in C and D represents the results from an individual recipient. Representative or pooled results from four (B–D, n = 15–19/each) or two (E–H, n = 5) independent experiments are shown. *, P < 0.05; **, P < 0.01; ***, P < 0.001; and ****, P < 0.0001 by ordinary one-way ANOVA.