Zymosan A, a polysaccharide derived from Saccharomyces cerevisiae, is a TLR2 agonist that can upregulate ASCL2 through the TLR2 and Wnt signaling pathways, promoting the regeneration of intestinal stem cells (ISCs) after radiation-induced injury. It exhibits significant radioprotective effects, helping to prevent and alleviate IR-induced intestinal damage. Additionally, Zymosan A can induce immune responses, inflammation, anorexia, and elevated body temperature, and is commonly used to establish peritonitis models.