Unlike previous studies with Helicobacter pylori where infection causes adenocarcinoma and produces high levels of IL-17 and IL-21 (Amedei et al., 2014), only moderate increase in signature cytokines secreted by Th17 cells, such as IL-17, IL-17F, IL-21, and IL-22 (Volpe et al., 2008; Korn et al., 2009), was observed in our experiments. Here, IL17F is linked to infection.