Fig. 3

In vitro characterizations of the T-lymphocytes treated with IFN-γ or/and 0.1 μg/ml nivolumab. a Control T-lymphocytes (black), IFN-γ alone treated T-lymphocytes (green), 0.1 μg/ml nivolumab alone treated T-lymphocytes (blue) and combination treated T-lymphocytes (red) were stained with trypan blue, and the proliferation and viability were detected. b The cytokine secretions of IFN-γ, TNF-α and IL-2 from each group were measured by flow cytometry using Cytometric Bead Array Human Th1/Th2 Cytokine Kit II. c Pancreatic cancer cell lines such as BxPC-3, PANC-1 and MIA PaCa-2 were pre-cultured prior to the addition of IFN-γ or/and 0.1 μg/ml nivolumab treated T-lymphocytes. The cytotoxic activity of each group was determined using a Cell Couning Kit 8 and calculated as follows: Cytotoxic activity, % = [1 - (OD_{effect and target cells} - OD_{effector cells})/OD_{target cells}] × 100. Data shown are mean ± standard deviation, two-tailed t test, *p < 0.05, **p < 0.01, ***p < 0.001, ****P < 0.0001, NS p > 0.05. Four biological replicates and three technical replicates were made in each group