Microglia play a pivotal role in the maintenance of brain homeostasis, but lose their homeostatic function during the course of neurodegenerative disorders. We identified a specific APOE-dependent molecular signature in microglia isolated from mouse models of amyotrophic lateral sclerosis, multiple sclerosis and Alzheimer’s disease (SOD1, EAE and APP-PS1) and in microglia surrounding neuritic A?-plaques in human Alzheimer’s disease brain. This is mediated by a switch from a (M0)-homeostatic to (MGnD)-neurodegenerative phenotype following phagocytosis of apoptotic neurons via the TREM2-APOE pathway. TREM2 induces APOE signaling which is a negative regulator of the transcription program in M0-homeostatic microglia. Targeting the TREM2-APOE pathway restores the M0-homeostatic signature of microglia in APP-PS1 and SOD1 mice and prevents from neuronal loss in an acute model of neurodegeneration. In SOD1 mice, TREM2 regulates MGnD in a gender-dependent manner. APOE-mediated MGnD microglia lose their tolerogenic function. Taken together, our work identifies the TREM2-APOE pathway as a major regulator of microglial functional phenotype in neurodegenerative diseases and serves as a novel target to restore homeostatic microglia. Overall design: Illumina NextSeq500 was used to identify disease-associated vs. homeostatic molecular microglia signature in microglia in different disease models and transgenic models. Bulk microglia (1,000 cells/sample) FCRLS+ sorted microglia.
The TREM2-APOE Pathway Drives the Transcriptional Phenotype of Dysfunctional Microglia in Neurodegenerative Diseases.
Specimen part, Cell line, Subject
View SamplesMicroglia play a pivotal role in the maintenance of brain homeostasis, but lose their homeostatic function during the course of neurodegenerative disorders. We identified a specific APOE-dependent molecular signature in microglia isolated from mouse models of amyotrophic lateral sclerosis, multiple sclerosis and Alzheimer’s disease (SOD1, EAE and APP-PS1) and in microglia surrounding neuritic A?-plaques in human Alzheimer’s disease brain. This is mediated by a switch from a (M0)-homeostatic to (MGnD)-neurodegenerative phenotype following phagocytosis of apoptotic neurons via the TREM2-APOE pathway. TREM2 induces APOE signaling which is a negative regulator of the transcription program in M0-homeostatic microglia. Targeting the TREM2-APOE pathway restores the M0-homeostatic signature of microglia in APP-PS1 and SOD1 mice and prevents from neuronal loss in an acute model of neurodegeneration. In SOD1 mice, TREM2 regulates MGnD in a gender-dependent manner. APOE-mediated MGnD microglia lose their tolerogenic function. Taken together, our work identifies the TREM2-APOE pathway as a major regulator of microglial functional phenotype in neurodegenerative diseases and serves as a novel target to restore homeostatic microglia. Overall design: Illumina NextSeq500 was used to identify disease-associated vs. homeostatic molecular microglia signature in microglia in different disease models and transgenic models. Bulk microglia (1,000 cells/sample) FCRLS+ sorted microglia.
The TREM2-APOE Pathway Drives the Transcriptional Phenotype of Dysfunctional Microglia in Neurodegenerative Diseases.
Sex, Specimen part, Cell line, Subject
View Samples