Fig. 2.

Nonspecific ADCC responses mediated by CD56+ T,CD56+ NK and CD56− T cells. a Representative flow plots showing the capacities of CD56+ T,CD56+ NK and CD56− T cells to respond to P815 cells coated with P815-specific Abs (P815+ Ab), p815 cell alone, or medium. Positive ADCC responses were represented by increased CD107a expression and IFNγ secretion. b Nonspecific ADCC activities mediated by CD56+ T, CD56+ NK and CD56− T cells were evaluated in 36 healthy donors. The difference of percentage (P815/Ab minus P815) of CD107a+ and IFNγ+ cells in CD56+ T,CD56+ NK and CD56− T cells stimulated by Ab-bound P815 cells was shown. The horizontal bar indicated median values. c MFI loss (P815 minus P815/Ab) of CD16 on CD56+ T, CD56+ NK and CD56− T cells following stimulation with Ab-bound P815 cells. Horizontal bar indicated median value. d MFI loss of CD16 was correlated with CD107a+ expression in CD56+ T cell-mediated nonspecific ADCC response. e CD107a expression was correlated with IFNγ production in CD56+ T cell-mediated nonspecific ADCC responses. f Purified CD56+ T cells were co-cultured with P815 cells or Ab-bound P815 cells for 24 h and levels of IFNγ in cell supernatants were detected by ELISA. g Representative flow plots showing lytic capacities of purified CD56+ T, NK, CD56-T cells co-cultured with P815 cells or Ab-bound P815 cells for 10 h. Target P815 cells were shown as PKH26+ cells and CFSE^−/low target cells indicated lysed target cells. h The percentage of lysed target cells induced by CD56+ T, CD56+ NK and CD56− T cells in healthy donors (n = 10). All P values were two-tailed and considered significant when less than 0.05