IFNG and neoplasm: Moreover, it was observed that higher IFN-γ+ frequency of PD-1+ CD8+ T cells isolated from VV-treated MC38 tumor cell suspensions in the in vitro coculture with MC38 tumor cells in the presence of purified iPDL1 in comparison to the presence of control IgG (Fig. 7i), suggesting the role of secreted iPDL1 in overcoming the immunosuppression of PD-L1+ tumor cells.