Disruption of the CX3CL1–CX3CR1 axis leads to dysregulation of microglial and neuronal damage in various animal models of neurodegenerative diseases such as Parkinson’s disease, ischemic stroke, Alzheimer’s disease, and mild traumatic brain injury [63,64,65,66]. Here, CX3CR1 is linked to early-onset autosomal dominant Alzheimer disease.