RESUMO
The treatment of tumors with oncolytic viruses is an important cancer immunotherapy strategy. Interleukin-15 (IL-15) can enhance the antitumor effect of natural killer cells and T cells. An oncolytic herpes simplex type II virus (oHSV2-mIL-15CherryFP) expressing mouse IL-15 was constructed using the CRISPR/Cas9 system, and its antitumor activity in vitro and in vivo was evaluated. In vitro, the mouse interleukin-15 (mIL-15) present in the culture supernatant expressed by oHSV2-mIL-15CherryFP was able to enhance the killing of CT26-GFP tumor cells by T cells. In addition, the intratumoral injection of oHSV2-mIL-15CherryFP inhibited tumor growth in the CT26-iRFP and BGC823-iRFP model. These results indicate that the use of oncolytic herpes simplex virus expressing IL-15 may be a potential therapeutic strategy in tumor immunotherapy.