CX3CR1 and Alzheimer disease: While neurons secrete higher levels of CX3CL1 upon CNS injury [65], leading to neuroprotection via a downregulation of pro-inflammatory cytokine production (nitric oxide, IL6, TNFα) by activated microglia [66], decreased neuroinflammation has been described for Alzheimer’s disease [67,68] and stroke [69] in CX3CR1−/− mice.