Effect of Helicobacter pylori infection on Lgr5+ stomach epithelial cells

Wnt signaling stimulated by R-spondin (Rspo) via binding to Lgr family members is crucial for stem cell renewal and tissue homeostasis in the gastrointestinal tract. In the stomach, Rspo is secreted by myofibroblasts and controls epithelial gland regeneration by inducing proliferation of Wnt-responsive Axin2+ cells in the isthmus of glands. Infection with Helicobacter pylori results in increased expression of stromal Rspo, leading to an expansion of Axin2+ isthmus stem cells and gland hyperplasia. Basal Lgr5+ cells are exposed to Rspo3 but the effects of this are not well understood. Here we demonstrate that, in the antrum, endogenous Rspo3, apart from its activity as a mitogen, regulates Lgr5+ cells in the gland base and induces their differentiation towards secretory cells.