CD80 and neoplasm: All armed OVs, including OV-OX40L, OV-IL12, and OV-OX40L/IL12, increased the expression of the costimulatory receptors CD80 and CD86 on tumor cells, with the strongest upregulation observed in cells infected with OV-OX40L/IL12, followed by OV-OX40L and OV-IL12.