Fig. 6
Blockade of mast cell-associated PD-L1 on T cell immunity inhibits tumor growth and GC progression in vivo. a Mice were injected with human SGC-7901 cells, as described in Materials and methods. The control animals (
) received no further injections. The experimental treatments entailed injections with T cells (
) or T cells in combination with TTCS-conditioned mast cells (TCM) (
), or T cells in combination with TCM pre-treated with an anti-PD-L1 antibody (
) or a control IgG (
). The illustrated data represent tumor volumes (5 mice in each group). The day of tumor cell injection was counted as day 0. *P < 0.05, for groups injections with T cells in combination with TCM pre-treated with an anti-PD-L1 antibody (
), compared with groups injections with T cells in combination with TCM pre-treated with a control IgG (
). The tumors were excised and photographed 21 day after injecting the tumor cells. b The weights of tumors were compared. c-e Proliferating cell nuclear antigen (PCNA) (brown) expression, CD3+ T cell infiltration (brown) (c), or IFN-γ (d), perforin and granzyme B (e) production in tumors and IFN-γ-producing T cell response (d) in spleens of mice were compared (n = 5). Scale bars: 100 μm. The horizontal bars represent mean values. **, P < 0.01; n.s., P > 0.05 for groups connected by horizontal lines