Gastric Cancer Mesenchymal Stem Cells Inhibit NK Cell Function through mTOR Signalling to Promote Tumour Growth

Figure 4

Attenuated cytotoxicity of NK cells after treatment with by GCMSC-CM. (a) Cytotoxicity against MKN-45 targets by NK92 cells previously treated with or without GCMSC-CM. Representative FCM plot of PI expression in target cells. (b) Six-hour cytotoxicity assay of NK92 cells against MKN-45 cells. Cytotoxicity of NK92 against MKN-45 cells at the indicated ratios (NK cells/target cells) (left). Quantification of the cytotoxicity assay at a ratio of 1 : 1 (right). (c) Cytotoxicity against HGC-27 target cells by NK cells derived from healthy donors. Representative FCM plot of PI expression in target cells. (d) Six-hour cytotoxicity against HGC-27 cells of NK cells pretreated with GCMSC-CM. Cytotoxicity of NK cells against HGC-27 cells at the different ratios (left). Quantification of the cytotoxicity assay at the indicated ratios (right). (e) NK 92 cells were treated with GCMSC-CM for 48 h, and TGF-β expression was evaluated through immunoblotting.

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