CX3CL1 and Parkinson disease: In brain neurodegenerative pathologies, CX3CL1‐CX3CR1 signaling is important in determining disease outcomes in models of Parkinson's disease (Cardona et al., 2006), multiple sclerosis (Garcia et al., 2013), and Alzheimer's disease (Cho et al., 2011; Fuhrmann et al., 2010).