Zoledronate but not pamidronate induces IFN-γ production in NK cells: γδ T lymphocytes regulate survival of DC-like cells. CD56⁺ PBMCs (2 × 10⁶/mL) were stimulated for 20 hours with either IL-2 alone (100 U/mL) or with bisphosphonate (10 or 30μM) plus IL-2. Cells were stained for intracellular IFN-γ and for surface CD14 (DC-like cells; A) or TCRVδ2 (γδ T lymphocytes) and CD3 (all T lymphocytes; B). Frames point out DC-like cells. Arrows point out Vδ2⁻ and CD3⁻ cells (ie, NK cells) producing IFN-γ. Results are representative of 3 independent experiments.