Furthermore, these mice had reduced glioma volume, similar to that observed in EE-housed mice, and in contrast with mice receiving vehicle or rAAV2-GFP microglia (n = 5–7 mice, veh 4.45 ± 0.72 mm3; rAAV2-GFP 4.52 ± 0.75 mm3; rAAV2-IL-15 1.47 ± 0.34 mm3; EE 0.72 ± 0.37 mm3) (Figure 3C). The gene discussed is IL15; the disease is glioma.