Interaction with Mesenchymal Stem Cells Provokes Natural Killer Cells for Enhanced IL-12/IL-18-Induced Interferon-Gamma Secretion
Figure 1
MSC exert a dose-dependent activating effect on IFN-γ secretion by NK92 cells. NK92 cells were cultured in the absence or presence of MSC at NK : MSC ratios of 20 : 1, 10 : 1, 5 : 1, and 1 : 1 (a and b) or 5 : 1 (c and d). Interleukin- (IL-) 12 (1 ng/mL) and IL-18 (10 ng/mL) were added directly after seeding the NK92 cells (a and c) or 24 h after preincubation of MSC and NK cells (b). After 24 h, the IFN-γ concentration in the supernatants was quantified by ELISA. Supernatants derived from unstimulated NK-cell cultures in the absence or in the presence of MSC show no detectable IFN-γ. Bar graphs show mean values ± standard deviation of triplicate cultures from one representative experiment out of three independent experiments done with three different donors for MSC. versus NK cells cultured alone.
