Microglial Cx3cr1 knockout prevents neuron loss in a mouse model of Alzheimer's disease

Abstract

Using two-photon imaging in a transgenic mouse model of Alzheimer's disease, the authors find that microglia, the resident macrophages of the brain, surround neurons prior to nerve cell death. They also find that inactivation of the microglial chemokine receptor CX3CR1, which is critical in neuron-microglia communication, prevents neuron loss. Microglia, the immune cells of the brain, can have a beneficial effect in Alzheimer's disease by phagocytosing amyloid-β. Two-photon in vivo imaging of neuron loss in the intact brain of living Alzheimer's disease mice revealed an involvement of microglia in neuron elimination, indicated by locally increased number and migration velocity of microglia around lost neurons. Knockout of the microglial chemokine receptor Cx3cr1, which is critical in neuron-microglia communication, prevented neuron loss.