PRF1 and cancer: cell lines and activated T cells were infected: parental OV resulted in translocation of PD-L1 to cell surface in cancer cells; antibody-encoding OV delivered sufficient α-PD-L1 scFv to block cell surface detection of PD-L1 on cancer cells; OV-encoded scFv increaseed granzyme B production and prevented OV-induced decrease in perforin release by T cells (166).