Figure 2. Adaptive NK cells resist MDSC suppression.

A) Purified NK cells from healthy blood donors were cultured alone or in contact with MDSCs or monocytes at a 2:1 ratio in the presence of IL-15 (10 ng/ml) for 5 days or B) in transwells allowing exchange of soluble factors only. Cells were stimulated with anti-CD16 six hours prior to staining, and degranulation, IFN-γ and TNF-production, as well as proliferation (Ki67) were assessed by flow cytometry. Pooled data of 5–7 independent experiments are shown as the mean ± SEM and statistical analysis were done using the Two-Way ANOVA.