Purified γδ T cells produced IFN-γ in response to ESAT-6. (A) Purified γδ T cells and γδ-depleted cells by magnetic beads from PBMCs are shown. The numbers represent the percentage of the purity of each population in one representative experiment. (B) CD4-depleted cells from PBMCs were prepared. (C) PBMCs, purified γδ T cells, γδ-depleted cells, and CD4-depleted cells were cultured with or without ESAT-6 at different concentrations. After stimulation, IFN-γ production was detected by ELISA (mean ± SD). *P > .05; ***P < .001.