Figure 2.

ZIKV infection results in immune-mediated tumor control in GBM models

(A–D) C57BL/6N mice were injected intracranially with GL261 cells plus ZIKV-FSS. Two days before injection, mice were left untreated or treated with depletion Abs against CD3, CD4, or CD8 T cells, as shown by the schematic (A). Representative images of H&E-stained sections of mouse brains collected on day 16 after GL261 cell transplantation are shown (B). Scale bars, 2 mm. A Kaplan-Meier survival plot of mice is shown (C, log rank test). Depletion of T cells in tumors was determined by flow cytometry (D). (E–H) C57BL/6N mice were injected intracranially with CT2A cells. Mice were left untreated or treated with depletion Abs against CD3, CD4, or CD8 T cells on day 5 and then left untreated or treated with ZIKV-FSS on day 7 after implantation, as shown by the schematic (E). A Kaplan-Meier survival plot of mice is shown (F, log rank test). The proportions of CD4⁺ or CD8⁺ T cells (G) or activation of CD8⁺ T cells (H) were determined by flow cytometry. (I) Cell proliferation in tumors from (A) was determined by Ki67 IHC staining. Ki67⁺ cells were compared with all cells in 4 tumors from each group, and the percentages of Ki67⁺ cells are shown. Scale bars, 100 μm. Data are presented as means ± SD. ∗∗p < 0.01, ∗∗∗p < 0.001, as assayed by unpaired Student’s t test or Welch’s t test.