Extended Data Fig. 2: MALT1 regulates PD-L1 expression in a paracaspase-dependent manner.
a, MFI of cell surface PD-L1 expression from B16F10 CTRL- and MALT1-KD (KD1 and KD2) cells. Data represent mean ± SD. b, MFI of cell surface PD-L1 expression from B16F10 CTRL- and MALT1-KD cells after CD8+ T cell killing for 12 h at E:T ratio of 3. Data represent mean ± SD. c-d, Quantification of MFI of cell surface PD-L1 expression of the cancer cells isolated from CTRL or MALT1-KD tumor tissues formed by E0771 (c) and B16F10 (d) cell lines respectively. Data represent mean ± SD. e, Representative immunoblotting images of stable E0771 cell lines with VEC, M-WT, and M-PD overexpression. β-actin was used as a loading control. The experiment was independently repeated three times with similar results. f, Representative crystal violet staining images of surviving E0771-VEC, E0771-M-WT, and E0771-M-PD after co-culture with activated CD8+ T cells for 24 h at E:T ratio of 3. The experiment was independently repeated three times with similar results. g, MFI of cell surface PD-L1 expression from B16F10-VEC-, M-WT-, and M-PD- cells. Data represent mean ± SD. h, MFI of cell surface PD-L1 expression from B16F10-VEC-, M-WT-, and M-PD- cells after co-culture with activated CD8+ T cells for 12 h at E:T ratio of 3. Data represent mean ± SD. i, Quantification of MFI of cell surface PD-L1 expression of the cancer cells from tumor tissues generated by B16F10 cells overexpressing VEC, M-WT or M-PD. Data represent mean ± SD. For a, b, g, and h, n = 3 biological independent samples per group. For c, d and i, n = 3 mice per group. For a-d, g-i, unpaired two-tailed t-test.
