Figure 6.
Treatment effects of tumor infiltrating lymphocytes in the injected and uninjected tumor. Mice were subcutaneously implanted with 2.4 × 105 (injected tumor) and 1.2 × 105 (uninjected tumor) B16-OVA cells subcutaneously on contralateral flanks. One week later, mice were randomly distributed into indicated treatment groups (n = 5) and injected intratumorally with VSV-NDV (VN) at a dose of 107 TCID50 or PBS in an equal volume of 50 µL on day 0, followed by an intravenous OTI T cell injection (1 × 106) on day 1 for combination treatment or OTI monotherapy. Virus/PBS treatment was repeated on days 7 and 14. Tumors from both flanks were harvested on day 8, 15 and 22 after the first treatment. Single cell suspensions were generated from tumor tissues, and lymphocytes were isolated by gradient centrifugation. Tumor infiltrating lymphocytes (TILs) were then analyzed for CD8 surface expression (A) and OVA-specificity (B) via flow cytometry. Cell counts were normalized to tumor size measured before harvesting. Data are presented as mean + SD, and statistical significance was determined by student’s t-test. (C) Tumor size was correlated with OVA-specific T cell infiltration in a nonparametric Spearman correlation using GraphPad.