Fig 6. NK cells that secrete IFN-γ early have higher CD16 surface expression.
(AB): The distributions (black columns) of tSecrete of single-NK cells were positively skewed, indicating the existence of a faster secretor subpopulation within the population of NK cells that secrete IFN-γ. The corresponding normal distributions (red curve) were plotted using the same mean and standard deviation of tSecrete of single-NK cells. The relative comparison of CD16 (C) or CD56 (D) surface expression of early secretors (tSecrete < population mean) and late secretors (tSecrete > population mean). (E) The amount of IFN-γ secreted by NK cells during the 6 h period of observation was statistically different across two donors. The amount of IFN-γ secreted is inferred from the ratio of fluorescent intensities (ratio of maximum and minimum value) from the fitting curve; (F) The relative IFN-γ secretion rate was a donor-dependent parameter. The rate of secretion of IFN-γ was inferred from the Hill slope (MFI versus time) obtained from curve fit on two different donors (donor 1: light red; donor 2: dark red). Error bar: mean and 95% confidence intervals are shown. Mann-Whitney test was performed, ns: not significant, ***: p-value < 0.001, ****: p-value < 0.0001.