Fig. 4.
Intact immune system and checkpoint blockade is required for optimal tumour control when combining NDV and radiation:
(a) Mouse treatment scheme with average tumour volume progressions. 200,000 B16-F10 melanoma cells were implanted in the right flank of (B) athymic mice (n = 5 mice per group) or (C-E) wild-type mice (n = 7–8 mice per group).
(b) 9 days post implantation, tumours were treated with five intratumoural administrations of NDV at 107 pfu every two days vs. mock-treatment. Certain cohorts of the tumour implanted mice received radiation (20 Gy in one fraction) with or without NDV. Tumour volumes were measured until the humane end point, and the average tumour volume progressions are shown.
(c-d) Wild-type immunocompetent C57BL/6 mice were implanted with 200,000 B16-F10 melanoma cells in the right flank. Beginning 9 days post implantation, tumours were irradiated (10 Gy in one fraction), treated with five intratumoural administrations of NDV at 107 pfu every two days and three i.p. injections of anti-PD1 every 4 days and compared to mock-treated animals. (c) Overall survival and (d) the individual tumour volume progressions are shown. Statistical analyses for Kaplan-Meyer survival curves and the complete clinical response rates were conducted with the Mantel-Cox test. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.