Fig. 3.

Direct contact between DC and γδ T cells is required for optimal activation of γδ T cells by PSK. a Representative overlay histograms and summary graphs showing CD25 expression in PSK-treated purified γδ T cells, γδ + DC co-culture, and γδ + DC trans-well culture. b Representative overlay histograms and summary graphs showing CD69 expression in PSK-treated purified γδ T cells, γδ + DC co-culture, and γδ + DC trans-well culture. Gray histogram: control; empty histogram: PSK-treated γδ T cells. c Dose-dependent induction of CD25 and CD69 on γδ T cells in γδ + DC co-culture. Black histogram: control; gray histogram: low-dose PSK (10 μg/ml); white histogram: high-dose PSK (100 μg/ml)