Figure 6.

Toxoplasma gondii ΔGRA17 changes immune status inside the tumors. (A) Volcano plots show overall gene expression levels of the injected (T2), distant tumors (T1) and control group (C) as determined by using a NanoString platform. (B) Heatmap shows the expression profile of immune-related pathways in B16-F10-bearing mice (n=4 mice per group) treated with phosphate buffered saline (PBS) or 5×10⁴ ΔGRA17 tachyzoites. Red and blue color indicate high and low expression, respectively. (C) Upregulation of programmed death ligand-1 (PD-L1) in tumor cells in injected tumors and distant tumors as revealed by immunofluorescence analysis. (D) Expression profile of antigen processing genes of tumors from B16-F10-bearing mice (n=8 mice/group) treated with PBS or ΔGRA17. Red indicates high expression, and blue indicates low expression. (E, F) Expression of representative antigen processing-related genes, chemokine genes and T cell response-related genes in the injected and distant tumors was determined by quantitative reverse transcriptase PCR. Data are shown as mean±SD of three independent experiments; Student’s t-test, *p<0.05, **p<0.01, **p<0.001, n/s, not significant, compared with the indicated control.