These results imply that TREM2‐mediated phagocytosis can be associated with the presence of ePtdSer beyond the normal processes of synapse pruning because ePtdSer also can be exposed on damaged neurons or glial cells during the progression of neurological diseases as well.[5, 6] However, the role of ePtdSer in the injured brain during the progression of diseases remains unclear; therefore, TREM2‐mediated phagocytosis in the vicinity of brain lesions such as Aβ plaques in the brains of the patients with Alzheimer's disease (AD) should be studied in the context of the presence of ePtdSer. Here, TREM2 is linked to Alzheimer disease.