Fig. 3

Phenotype of Friend virus (FV)-specific PD-1⁺ SIRPα⁻ and PD-1⁺ SIRPα⁺ CD8⁺ T cells in mice chronically infected with FV. Splenocytes from mice chronically infected with FV were analyzed by multiparameter flow cytometry for surface expression of (a) CD122, (b) Tim3, (c) Lag3, (d) CD95 (Fas), (e) CD43, (f) CD44, (g) CD40, (h) CD278 (inducible T cell co-stimulator), (i) KLRG1, (j) CD62L, (k) CD47, and (l) CX₃CR1. A representative off-set histogram overlay is displayed for each marker as well as the average geometric mean fluorescence intensity (MFI) from one experiment is given (n = 4 mice). CD8⁺ dextramer⁻ cells (non-DbgagL-specific cells from infected mice) are shown in dashed gray, PD-1⁺/SIRPα⁻ CD8⁺ dextramer⁺ cells are shown in solid line gray, and PD-1⁺/SIRPα⁺ CD8⁺ dextramer⁺ are shown in black. The vertical dashed line delineates positivity relative to the FMO control). Results are from one of three independent experiments with similar results (with n = 8 additional mice). ns, p > 0.05, *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, ****p ≤ 0.0001 (unpaired, two-way t tests). The flow cytometric gating strategy is shown in supplementary Fig. 6h–m