Fig. 3: Phenotypic analysis of PB CX3CR1⁺ CD8⁺ T cells before and during ICI therapy.

a–c CT26 (a–c) or MC38 (c) tumor-bearing mice were treated with anti-PD-L1 Ab and anti-CTLA-4 antibody (Ab) every 3 days and every other day, respectively. Peripheral blood (PB) was obtained before and 1, 2, and 3 weeks after the initiation of the treatment. Gating strategy: all cells > size lymphocytes > singlets > live > CD3⁺ CD8⁺ > CD27, CX3CR1. a Ki-67 expression of CD27^lo CX3CR1⁻ (green), CD27^hi CX3CR1⁻ (blue), and CX3CR1⁺ (red) CD8⁺ T cells in PB 2 weeks after ICI therapy. Numbers denote percent Ki-67⁺ cells. The data panel shows the median fluorescence intensity (MFI) of Ki-67⁺ cells in each subset. n = 4 mice in all groups. b Box and whiskers plots showing MFI of Ki-67⁺ (blue) and frequency (red) of the CX3CR1⁺ subset in CD8⁺ T cells (upper) and Tet⁺ CD8⁺ T cells (lower) at days 0, 7, 14, and 21 in PB. n = 3 mice (day 0) and n = 4 mice (days 7, 14, and 21). a, b Data shown are representative of two independent experiments. c Frequency of PB Tet⁺ CD8⁺ T cells in the CD27^lo CX3CR1⁻ (green), CD27^hi CX3CR1⁻ (blue), and CX3CR1⁺ (red) subsets before and 1, 2, and 3 weeks after the initiation of the treatment in CT26 (upper) and MC38 (lower) tumor-bearing mice. For CT26 tumor-bearing mice, n = 31 (day 0), n = 18 (day 7), n = 9 (day 14), and n = 9 (day 21) derived from three independent experiments. For MC38 tumor-bearing mice, n = 14 (day 0), n = 29 (day 7), n = 19 (day 14), and n = 8 (day 21) derived from three independent experiments. P-values were determined by one-way repeated measures ANOVA with Tukey’s multiple comparisons (a, c). Box plots: dot, single PB; hinges, 25th and 75th percentiles; middle line, median; whiskers, minimum to maximum value (a–c). Source data are provided as a Source Data file.