Vγ9Vδ2+ cells were also shown to have anti-tumour activity against CML cells in vitro and in vivo; however, this required the pre-treatment of CML cells with zoledronate and the administration of zoledronate plus IL-2 to mice in order to stimulate PAg expression on the tumour cells and maintain Vγ9Vδ2 T-cell activation [143]. The gene discussed is IL2; the disease is neoplasm.