IL2 and leukemia: In just 3 hours, more than 80% of leukemia cells were killed by the γδ T-cells that had been stimulated with a combination of HMB-PP with IL-2 (compared to less than 20% by non-activated γδ T-cells), and such a regimen was at least as effective as saturating αCD3 plus IL-2 (Figures 6A–B).