UV-HSV-1 potentiates the therapeutic efficacy of allogeneic donor PBMC infusions in a murine model of human leukemic. (A) Peripheral blood leukemia burden was analyzed by flow cytometry gating on live GFP/YFP+ lymphocytes/monocytes 26 days after implantation of MN1/ND13 cells in sublethally irradiated NRG-3GS mice. (B) Purified NK cells from 2 healthy donors were exposed to 0.1 pfu/PBMC of UV-HSV-1 for 16 hours, ±EasySep-purified autologous monocytes (∼85% purity) at a ratio of 2:1 NK:monocyte. After incubation, only floating cells were collected, and their cytolytic activity against MN1/ND13 cells was determined. *P < .01 from condition without monocytes. (C) Twenty-eight days after implantation of MN1/ND13 cells, mice were intravenously injected with PBS, T cell–depleted healthy human PBMCs (3 × 106 cells), or T cell–depleted PBMCs exposed ex vivo to UV-HSV-1 (3 × 106 cells; 0.1 pfu/PBMC; 16 hours). Kaplan-Meier analysis was performed on surviving fractions.
