Figure 3.

Peptides released by 624-38 human melanoma cell line upon Salmonella infection activate tumor-specific CD8⁺ T cells derived from healthy donor PBMCs

(A) MFI (mean fluorescence intensity) of HLA-A^∗02:01 of T2 cells loaded with secretomes of 624-38 and HT-29 cells infected with Salmonella (Salm) with or without Heptanol (Hept) or left untreated (−).

(B) Scheme of CTL-Vax and CTL-Mart1_26-35 expansion from healthy donor PBMCs.

(C) Tumor cell targets. HLA-A2^∗02:01 and Mart1 antigen expression are indicated.

(D and E) Frequency of CD3⁺CD8⁺IFN-γ⁺ (activated) or CD3⁺CD8⁺CD107a⁺ (degranulating) CTL-Vax (D) and CTL-Mart (E) upon co-culture with target cells. Pan HLA-blocker (anti HLA) antibody was added as control, where indicated.

(F) Tumor growth curves of NSG mice injected with 624-38 melanoma cells, adoptively transferred with CTL-Vax (blue) or with CTL-Mart1 (red) at day 7 after tumor injection.

(A, D, and E) Data are pooled from three or more experiments and are expressed as mean ± SE using scatter dot plot. Statistical analysis was evaluated using one way ANOVA (A and F) or two-sided Mann-Whitney test (D and E). ^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗p < 0.001, ∗∗∗∗p < 0.0001. See also Figures 4, 5, and 6.