CX3CR1 and Cognitive impairment: The deficiency of CX3CL1 or CX3CR1 in AD models reduces β-amyloid deposition but increases tau phosphorylation and aggregation, with a consequent detrimental effect on the behavioral and cognitive deficit (Bhaskar et al., 2010; Fuhrmann et al., 2010; Lee et al., 2010, 2014; Liu et al., 2010; Maphis et al., 2015; Merino et al., 2016).