Figure 3.

Pre-existing Immunity to NDV Potentiates Local, Abscopal, and Systemic Anti-tumor Immune Responses

(A) Treatment scheme. Tumors were established by implantation of 2 × 10⁵ B16-F10 cells in the right and left flanks. (B) Relative cell type gene signature scores from the NDV-treated tumors of NDV-naive and NDV-immunized mice (all n = 5). (C) Absolute number of tumor-infiltrating CD8⁺ and CD4⁺FoxP3⁻ (T_con) cells per gram of tumor calculated from flow cytometry of treated tumors. (D) Representative flow cytometry plots of percentages of T_con and T_reg cells (left) and average percentages of T_reg cells (right). (E) Calculated CD8⁺:T_reg and T_con:T_reg ratios in the treated tumors. (F) Relative cell type gene signature scores from the distant tumors of NDV-naive (n = 9) and NDV-immunized (n = 5) mice treated with NDV. (G) Relative expression of genes related to T cell response in the distant tumors of NDV-treated NDV-naive and NDV-treated NDV-immunized mice. (H) Absolute number of tumor-infiltrating CD8⁺ and T_con cells per gram of tumor calculated from flow cytometry of distant tumors. (I and J) Representative flow cytometry plots with percentages of T_con and T_reg cells (I) and average percentages of T_reg cells calculated from flow cytometry in distant tumors (J). (K) Calculated CD8⁺:T_reg and T_con:T_reg ratios. (L and M) Production of IFNγ in response to re-stimulation of splenic CD8⁺ lymphocytes with (L) B16-F10 cells or (M) with MB49 cells infected with NDV (left) and non-infected MB49 cells (right). (N) Anti-NDV antibody serum titers (day 50) determined by HI. Data from (B), (F), and (G) represent results from one experiment. Data from (C)–(E) and (H)–(J) represent results from one of three independent experiments with n = 3–5 animals per group. Data from (K) represent combined results from two independent experiments with 8–14 animals per group. Data from (N) represent results from one of three independent experiments with n = 8–10 per group. Mean ± SEM is shown. ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001. R, right; BL, bilateral.