Figure 1.

ZIKV treatment induces T cell infiltration and activation in GBM models

(A–D) C57BL/6N mice were injected intracranially with GL261 cells mixed with ZIKV-FSS or ZIKV-GZ01. Kaplan-Meier survival plots of mice with the indicated treatment are shown (A). The percentages of CD4⁺ or CD8⁺ T cells in CD45⁺ CD3⁺ T cells in tumors were determined by flow cytometry (B). IHC staining of CD3⁺ and CD8⁺ T cells in tumors with the indicated treatment for 15 days are shown (C, left). CD3⁺ or CD8⁺ cells were compared with all cells in 5 randomly selected microscope fields from each of 5 tumors, and the percentages of CD3⁺ and CD8⁺ T cells are shown (C, right). Scale bars, 100 μm. The percentages of IFN-γ⁺ in CD4⁺ or CD8⁺ T cells in tumors with ZIKV-FSS treatment for 15 days were determined by flow cytometry (D). (E–I) C57BL/6N mice were implanted intracranially with GL261 cells expressing luciferase (E, F, and H) or CT-2A cells (G and I). Mice were grouped randomly and treated with ZIKV-FSS from day 7 after implantation, as shown by the schematic (E, top). The xenografts were tracked by bioluminescence, and representative images are shown (E, bottom). Bioluminescence quantification of tumor growth is shown (E, right). Kaplan-Meier survival plots of mice are shown (F and G; log rank test). 12 days after treatment, the proportions of CD3⁺ T cells in CD45⁺ cells, CD4⁺ or CD8⁺ T cells in CD45⁺ CD3⁺ T cells, and IFN-γ⁺ or TNF-α⁺ cells in CD8⁺or CD4⁺ T cells (H) in tumors were determined by flow cytometry. The proportions of CD11c⁺ MHC class II⁺ cells in CD45⁺ cells and CD80⁺ or CD86⁺ cells in CD45⁺ CD11c⁺ MHC class II⁺ cells in tumors with ZIKV-FSS treatment for 15 days were determined by flow cytometry (I). (J and K) Tumors treated with ZIKV-FSS for 15 days were harvested, and gene expression analysis was performed using RNA-seq. Pathway enrichment analysis using GSEA (K) and visualization using Cytoscape Enrichment Map (J) in tumors with ZIKV infection are shown. Red nodes represent pathways that are upregulated and blue nodes represent pathways that are downregulated in ZIKV-infected tumors compared with control tumors (FDR < 0.05). Data are presented as means ± SD. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, as assayed by unpaired Student’s t test or Welch’s t test.