Interaction with Mesenchymal Stem Cells Provokes Natural Killer Cells for Enhanced IL-12/IL-18-Induced Interferon-Gamma Secretion
Figure 2
MSC promote the secretion of IFN-γ by NK92 cells both by cell-cell contact as well as by soluble factors. (a) NK92 cells were cultured in the absence or presence of MSC at a NK : MSC ratio of 5 : 1 in a contact or a transwell system. IL-12 (1 ng/mL) and IL-18 (10 ng/mL) were added 24 h after preincubation of MSC and NK cells. (b) NK92 cells were cultured in the absence or presence of MSC at a NK : MSC ratio of 5 : 1. After 24 h the supernatant (S) was harvested and transferred to fresh NK92 cells prior to stimulation with IL-12 (1 ng/mL) and IL-18 (10 ng/mL) for 24 h. The IFN-γ concentration in the supernatants was quantified by ELISA. 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. .
