All patients received prior lymphopenia-inducing chemotherapy (fludarabine 20-25 mg/m2 day -6 until day -2 and cyclophosphamide 30-60 mg/kg day -6 and -5) and were treated with 4 mg zoledronate on day 0 and 1.0x106 IU/m2 IL-2 on day +1 until day +6 for the induction of γδ T cell proliferation in vivo. Here, IL2 is linked to lymphopenia.