Downregulation of TREM2 expression induced cognitive dysfunction and exacerbated neuroinflammatory responses through the toll-like receptor 4 (TLR4) mediated MAPK signaling pathway in the APP/PS1 mouse model of AD (Ruganzu et al., 2022), while activation of TREM2 switched off the inflammatory response by inhibiting NLRP3 inflammasome and inflammasome complex assembly, through activation of beta-catenin (Wang et al., 2022). This evidence concerns the gene TLR4 and Alzheimer disease.