Figure 8.

GM-CSF conditioning requires NK cells and monocytes/macrophages in vivo and is applicable to other tumor models and cytokines. (a) Reovirus-immune C57Bl/6 mice bearing 5-day established s.c. B16 tumors were depleted of CD8, CD4, NK, Ly-6G+, or Ly-6C+ve immune cell subsets (days 6 and 7; 13 and 14, 20 and 21) and received three cycles of GM-CSF/reovirus treatment (days 6–10, 13–17, and 20–24). (b) C57Bl/6 mice were vaccinated i.p. with reovirus (2 × 10⁷ TCID₅₀). After 14 days, mice were seeded with s.c. TC2 tumors and, 6 days later, treated with three cycles of PBS/PBS, PBS/reovirus, GM-CSF/PBS, or GM-CSF/reovirus. (c) Reovirus-immune C57Bl/6 mice bearing 5-day established s.c. B16 tumors were treated with one cycle of cytokine conditioning, ± reovirus, as indicated. In all cases, tumor size was monitored and animals were killed when tumors reached 1.0 cm diameter.