Polarization of IL-17⁺ Vγ9Vδ2 T cells is induced by antigen and IL-1β, IL-6, IL-23, and TGF-β. Intracellular cytokine staining for IL-17 and IFN-γ in naive (CD45RA⁺CD27⁺) human Vγ9Vδ2 T cells primed for 6 days with an equal number of irradiated DCs and IPP, in the presence of various combinations of cytokines, then incubated for 6-7 days more in IL-2 and stimulated for 6 hours with IPP. (A) Cumulative results (mean values ± SD) of 3 different experiments each performed with 5 different healthy donors. *P < .01 and **P < .05 compared with the medium group. (B) Typical flow cytometry panels of a representative experiment. Numbers in quadrants indicate percent cells in each.