Figure 5.

Effects of cancer-associated fibroblasts (CAFs) on natural killer (NK) cell activation markers. NK cells were incubated in mixed cultures with NFs or CAFs. NK cells treated with TGF-β served as control of repressed functional activity. Following co-culturing, NK cells were analyzed for (A) intracellular expression of cytotoxic enzymes perforin and granzyme B after being employed against K562 cells (NK to K562 ratio 5:1); (B) intracellular expression of pro-inflammatory cytokines IFN-γ and TNF-α after exposure to K562 cells (5:1); and (C) released levels of IFN-γ and TNF-α in culture media (fibroblast to NK ratio 1:2). Results in (A, B) were measured by flow cytometry, whereas cytokine release in (C) was quantified by ELISA. For intracellular markers, signal intensities are expressed as median fluorescence intensity (MFI). Data represents mean (± SD) values from three different CAF donors. Statistical P-values between NF and CAFs were determined using one-way ANOVA with Tukey correction for multiple comparisons. Extracellular levels in (C) are presented as mean (± SD) values from four random CAF donors.