IFNG and gastric cancer: After culture in vitro for a week, lymphocytes isolated from H. pylori-infected gastric cancer tissues (Hp+) displayed a vigorous ability to secrete IL-4 and an impaired function of IFN-γ secretion, when compared to those isolated from the H. pylori-uninfected individuals (Hp−) (Figures 3(c) and 3(d)).