Figure 3.

Toxoplasma gondii ΔGRA17 increases infiltration of tumors with lymphocytes. A treatment schedule shown in figure 1A was followed, B16-F10 tumors were harvested 24 hours after the second treatment (ie, on the 12th day), and digested for preparation of single-cell suspensions followed by antibody staining for CD45, CD3, CD4, CD8, NK1.1, CD11b, CD11c, interferon-gamma (IFN-γ), tumor necrosis factor-α (TNF-α), Ki67, and granzyme B. (A) Representative plots of the percentages of CD45⁺ cells, CD3 T cells, CD4⁺ T cells, CD8⁺ T cells, natural killer (NK) cells, macrophages, and dendritic cells (DCs) in phosphate buffered saline (PBS)-treated or ΔGRA17-treated tumors. (B) Percentages of CD45⁺ cells, CD3 T cells, CD4⁺ T cells, CD8⁺ T cells, NK cells, natural killer T (NKT) cells, macrophages, and DCs in PBS-treated or ΔGRA17-treated tumors. (C) Percentages of interferon-gamma (IFN-γ), tumor necrosis factor-α (TNF-α), ki67, and granzyme B in CD8⁺ T cells. (D) IFN-γ ELISPOT showing that tumor Ag TRP-2-specific CD8⁺ T cells in spleen are enriched in infiltrated lymphocytes. (E– G) A similar treatment schedule was followed as in figure 1A, except that LLC or MC38 tumor cells were used to inject the mice, instead of B16-F10 tumor cells. (E) LLC and MC38 tumor volume in mice. (F) Percentages of CD45⁺ immune cells, CD3 T cells, CD4⁺ T cells, CD8⁺ T cells, NK cells, NKT cells, macrophages, and DCs in phosphate buffered saline (PBS)-treated or ΔGRA17-treated LLC tumors. (G) Percentages of the CD45⁺ immune cells, CD3 T cells, CD4⁺ T cells, CD8⁺ T cells, NK cells, NKT cells, macrophages, and DCs in PBS-treated or ΔGRA17-treated MC38 tumors. Data are mean±SD (n=6 mice/group) of three independent experiments; Student’s t-test, **p<0.01, ***p<0.001 compared with the indicated control.