Extended Data Fig. 7: SIL2-EMSC expands and rejuvenates exhausted CD8⁺ TILs.

a-c, C57BL/6 J mice (n = 6) bearing MC38 were p.t. treated with 1 × 10⁶ EMSCs or SIL2-EMSCs on day 9 and 12. Five days after the last treatment, tumor-infiltrating T cells were analyzed for the fold change of number of PD1⁻TIM3⁻, PD1⁺TIM3⁻, and PD1⁺TIM3⁺ CD44⁺CD8⁺ T cell subsets (a) and the frequency of CXCR5⁺TIM3⁻ subset (b) and CD39⁺Tcf1⁻ subset (c) in PD1⁺TOX⁺CD44⁺CD8⁺ T cells in tumor were analyzed. d-f, CT26 bearing BALB/c mice (n = 5) were treated with 1 × 10⁶ EMSC or SIL2-EMSC on day 9 and day 12. Five days after the second treatment, TILs were analyzed for the number of CD8⁺ T cells (d) and the frequency of PD1⁻TIM3⁻, PD1⁺TIM3⁻, and PD1⁺TIM3⁺ CD8⁺ T cell subsets (e) and stem-like exhausted CD8⁺ T cells (f). g-i, C57BL/6J mice (n = 5–6) bearing MC38 were p.t. treated with 1 × 10⁶ EMSCs or SIL2-EMSCs on day 9 and 12. Five days after the last treatment, TILs were analyzed for surface expression level of CD25 and CD122 (g, n = 6 per group), the frequency of Ki67⁺ cells (h, EMSC, n = 5; SIL2-EMSC, n = 6), and the frequency of active caspase 3⁺ cells (I, EMSC, n = 5; SIL2-EMSC, n = 6) in PD1⁻TIM3⁻, PD1⁺TIM3⁻, and PD1⁺TIM3⁺ CD8⁺ T cell subsets. j, k, MC38 bearing C57BL/6J mice (n = 4) were i.t. treated with single high dose (20 μg) or prolonged low dose (5 μg, 4 injections) on day 9. Prolonged low dose group were injected with SIL2 every 12 h. CD8⁺ TILs were analyzed for the frequency of PD1⁻TIM3⁻, PD1⁺TIM3⁻, PD1⁺TIM3⁺ CD8⁺ T cell subsets and (j) and stem-like CD8⁺ T cells (k). l, MC38 bearing C57BL/6J mice (n = 4) were treated with SIL2 (10 μg, i.t.) and/or EMSCs (1 × 10⁶, p.t.) and SIL2-EMSC (1 × 10⁶, p.t.) on day 9 and 12. Five days after treatment, CD8⁺ TILs were analyzed for the frequency of PD1⁻TIM3⁻, PD1⁺TIM3⁻, PD1⁺TIM3⁺ CD8⁺ T cell subsets. Data are shown as mean ± s.e.m. from two or three independent experiments. P value was determined by two-tailed unpaired t test (a–g,i–l). Source data are available online.

Source data