Fig. 1
Effect of VACV on tumor growth and post-therapy intratumoral PMN-MDSC kinetics. a Growth of HCT-116 tumors in LIVP 1.1.1 and control-treated mice. Tumor-bearing nude mice were treated with a single injection of LIVP 1.1.1 or LPS-nanoparticles or combination of both or PBS alone (uninfected). Tumor size was measured twice a week. Data shown are representative of two independent experiments with similar results. Error bars indicate SD (n = 3–5 mice/group). b Pre-treatment flow cytometry analysis of PMN-MDSCs in both tumor and spleen. A major iNOS+ cell subset with a phenotype of CD11b+ly6G+F4/80low was detected in single cell suspensions from both tumor and spleen. FACS plots are shown with the population of interest (PMN-MDSCs) in bold circles. c, d Accumulation kinetics of PMN-MDSC upon VACV treatment. The absolute numbers of PMN-MDSCs were determined by flow cytometry. Results are expressed as the average number of cells per gram of tissue and were obtained from three separate experiments with 3–5 mice. Error bars represent mean and SD. The differences between the VACV alone treated group (dark gray bar) and untreated controls (light gray bar) were significant for day 14 (tumor; p = 0.014 and spleen; p = 0.02) and for day 21 (tumor; p = 0.006). Black bars and light gray bars represent LIVP 1.1.1 + LPS-nanoparticles combination and untreated controls respectively