Fig 1: CLDN18-ARHGAP gene fusion generates an immunostimulatory peptide recognized by autologous and donors’ T cells.Autologous PBMCs from one PC GC patient with HLA-A*11:01 typing and CLDN18(e5)-ARHGAP26(e12) fusion gene were isolated and added to 3 separate experiment holes. They were stimulated with CLDN18(e5)-ARHGAP26(e12)-derived peptides, CLDN18-derived WT peptides or ARHGAP26-derived WT peptides every 3 days in the presence of IL-2, and T-cell response to each peptide were analyzed on day 10 by (A) IFN-γ ELISPOT assays and quantification of IFN-γ spots (n = 2 biological replicates), (B) quantification of IFN-γ in CBA assays (n = 3 biological replicates), and (C) detection of CD137 expression on CD8+ T cells via flow cytometry. T cells from one healthy donor were isolated and stimulated with APCs loading P1 every 7 days in the presence of IL-2. After 2-round stimulation, T-cell response to P1 was analyzed on day 15 by (D) IFN-γ ELISPOT assays and the quantification of IFN-γ spots (n = 3 biological replicates), (E) quantification of IFN-γ in CBA assays (n = 3 biological replicates), and (F) detection of CD137 and P1-specific tetramer expression on CD8+ T cells via flow cytometry. (G) Immunostimulatory cytokines including TNF-α, IFN-γ, and IL-6 from the culture of donor T cells stimulated with IL-2 and APCs loading P1 or WT peptides were detected by CBA. The increase of IFN-γ, TNF-α, or IL-6 more than twofold was considered different (n = 3 biological replicates). Data information: The data with error bars are shown as mean ± SEM. Source data are available online for this figure.