REG3G and diabetes mellitus: NOD mouse models can be divided into two colonies (high or low diabetes incidence), transplanting intestinal flora from low-incidence NOD mice to high-incidence NOD mice did not change the incidence of diabetes, but transplantation of A. muciniphila to high-incidence NOD mice can promote mucogenesis, increase the expression of antimicrobial peptide Reg3γ, inhibit the growth of rumen contortus, reduce the level of serum endotoxin, reduce the expression of TLR in pancreatic islets, promote regulatory immunity, and delay the development of diabetes (Hanninen et al., 2018).