A mouse model of CVN-AD, in which immune-mediated nitric oxide is reduced to mimic human levels, found areas of hippocampal neuronal death associated with the presence of immunosuppressive CD11c (+) microglia and extracellular arginase, resulting in decreased arginine catabolism and total levels of brain arginine (Kan et al., 2015). This evidence concerns the gene ITGAX and Alzheimer disease.