Wnt/β-Catenin Pathway Activation Confers Fumonisin B1 Tolerance in Chicken Intestinal Organoid Monolayers by Enhancing Intestinal Stem Cell Function

Fumonisin B1 (FB1) is a prevalent mycotoxin in moldy grains and feeds, highly toxic to livestock and compromising product quality while threatening food safety. Poultry exhibit low susceptibility to FB1, but the underlying tolerance mechanisms remain unclear. Traditional 3D chicken intestinal organoid models cannot simulate direct interaction between the epithelial monolayer and FB1, limiting the study of FB1-chicken intestinal crosstalk. Here, we established a 2D chicken intestinal organoid monolayer model, derived from intestinal crypts of 18-day-old specific pathogen-free chicken embryos, to systematically explore poultry's resistance mechanisms against FB1. Using this model, we compared FB1-induced effects with those in a porcine intestinal epithelial cell model. Results showed that FB1 exposure did not reduce transepithelial electrical resistance, induce abnormal expression of tight junction genes, or cause significant fluctuations in inflammatory factor levels in chicken intestinal organoid monolayers. Mechanistically, FB1 enhances chicken intestinal stem cell function by activating the Wnt/β-catenin pathway, thereby promoting epithelial regeneration and renewal to increase FB1 resistance and decrease toxin sensitivity in chickens. This study reveals a strategy for enhancing FB1 tolerance in poultry by promoting intestinal stem cell function, providing a new perspective for developing mycotoxin prevention and control strategies.