Fig. 5.

Fractionated FLASH X-ray is as competent as CONV IR in eradicating abscopal tumors. (A) Schema for tumor radioimmunotherapy. (B) CD3⁺CD8⁺ cells within primary and secondary tumors 5 d after the last injection of anti–PD-L1 antibody were tested by flow cytometric analysis (n = 5 mice per group). The quantified percentages of CD3⁺CD8⁺ cells in tumors are presented. (C and D) Tumor growth curves of primary (C) and secondary (D) tumors subjected to the indicated treatments are shown, and the numbers of tumor-free mice are indicated. (E) Kaplan–Meier survival analysis of tumor-bearing mice undergoing the indicated treatments was performed. Data are pooled from two independent experiments (B) or represent two independent experiments (C–E). Error bars indicate SEM. ***P < 0.001 and n.s. were determined by a two-sided Student’s t test (B) or determined by a log-rank test (E).