Figure 3.

Survival of the NK cells and their subset differentiation after co-culturing with MSC. NK cells were co-cultured with MSC for 3 days (with 100 U/ml rhIL-2), and their survival analyzed by both Annexin V/Propidium Iodide dual staining (A) and trypan blue dye exclusion (B). No difference was observed in NK cell survival between the different MSC co-cultures. Data presented in panel A is representative of 4 independent experiments. Data presented in panel B represents mean percent viable NK cells ± SD of 5 independent experiments, analyzed by Student’s pair t-test. (C) The phenotype of NK cells was assessed by flow cytometry after co-cultures with MSCs for 3 days. Percentages of CD56^bright and CD56^dim are shown from 3 different experiments with mean values ± SD. Data were analyzed using Student’s pair t-test. L-MSC, liver mesenchymal stromal cell; BM-MSC, bone marrow mesenchymal stromal cell; A-MSC, adipose mesenchymal stromal cell; NK, natural killer.