Most NSCLC-derived TIL products contain tumor-reactive T cells. (a, b) REP TILs were pre-stained with CD4 and CD8 antibodies, and cultured for 6 hours in the presence of brefeldin A with medium alone, with digests from normal lung tissue, or with autologous tumor digest. (a) Representative dot plots, and (b) compiled data of TIL products derived from 17 donors (top), and of T cells expanded from non-tumorous lung tissue from 11 donors (bottom). The percentage of IFN-γ producing CD3+ T cells (left panel), by CD4+ T cells (middle panel) and by CD8+ T cells (right panel) is depicted as determined by flow cytometry. Each dot represents one donor, box and whisker plots depict the median (line), minimum and maximum values (whiskers) and 25th pct and 75th pct (box). (c) TILs of 6 donors were expanded from the total digest, or from three distinct regions of the tumor lesion (region A,B,C). IFN-γ production of the different TIL products was compared after 6h of culture with the total tumor digest. (d) IFN-γ production by CD4+ and CD8+ T cells upon activation with PMA-Ionomycin. [Paired student’s T test; * p < .05; ** p < .01; *** p < .001. If no indication, p ≥ 0.05].