APP and Alzheimer disease: For example, APP/PS1 AD-Tg mice with IL-10 deficiency were found to display reduced cerebral Aβ plaque load and reduced synaptic and cognitive deficits27, while chronic overexpression of IL-10 in TgCRND8 AD-Tg mice57, which exhibit IL-10 elevation in both the CNS and plasma, exacerbated disease pathology.