HIV R5-tropic envelope glycoprotein induces Vγ2Vδ2 T cell death. (A) Vγ2Vδ2 T cells were expanded from healthy donor PBMC after stimulating with isopentenyl pyrophosphate (IPP, 15μM) plus IL-2 (100U/mL) for 14 days, and then purified by negative selection to ≥ 97% purity. (B-D) Cell death was evaluated after Vγ2Vδ2 T cells were incubated with soluble HIV gp120 proteins (BaL, CN54 or IIIB; 10 μg/mL) (A), HeLa cells or HeLa cells expressing HIV ADA-envelope (B), 293 cells transfected with empty vector or 293 cells expressing R5-tropic envelopes (BaL, SF162, JRFL, ADA, or YU2) (C) for 24 hours as described in “Methods.” Data are representative of 3 independent experiments (error bars, SD). The statistical significance compared with control was analyzed (*P < .05, **P < .005, ***P < .0001; Student t test). (E) Vγ2Vδ2 T cells were treated with HeLa cells or HeLa cells expressing HIV ADA-envelope for 24 hours and then stimulated with the TCR ligand IPP (15μM) for 4 hours. Cells were stained with annexin V and 7AAD. Data are representative of 3 independent experiments.