TLR9 and necrotizing enterocolitis: is positively correlated with the severity of NEC, while the depletion of Bifidobacterium and Lactobacillus weakens the intestinal immune defense capabilities.105,106 It is noteworthy that this dysbiosis is not dominated by a single pathogen but is the result of synergistic actions of multiple bacterial species.107 Shaw’s research introduced a microbial community pattern: the gut microbiota triggers NEC due to imbalanced stimulation of TLR4 and TLR9.