PDCD1 and neoplasm: However, the Tconv/Treg ratio of the combination treatment group did not show statistically significant differences compared to ZD55-IL-24 therapy alone or anti-PD-1 therapy alone groups (Supplementary Figure 1a, c), suggesting that ZD55-IL-24 was unable to help PD-1 blockade to further improve the tumor immune microenvironment.