Therefore the beneficial effect of the transient reduction of peripheral Tregs could be attributed to reduction in IL-10, and might shed new light on recent studies that demonstrated a detrimental role of this anti-inflammatory cytokine in AD pathology; APP/PS1 AD-Tg mice with IL-10 deficiency were found to display reduced cerebral Aβ plaque load and reduced synaptic and cognitive deficits65, while chronic overexpression of IL-10 in TgCRND8 AD-Tg mice, which induced IL-10 elevation in both the CNS and plasma, exacerbated disease pathology66. This evidence concerns the gene IL10 and Alzheimer disease.