In patients with non-ulcer dyspepsia, gastritis or peptic ulcers that were infected by H. pylori, a high secretion of IL-17, IFN-γ, IL-23, IL-6, IL-10, TNF-α, IL-21, IL-8, and IL-37 was reported [41,42,43,44,45,46,47]. Here, IL21 is linked to gastritis.