CD40 and Alzheimer disease: We demonstrated that CD40-CD40L interaction is critical for brain pro-inflammatory responses in aggravating AD-like pathology.50 As LISPRO treatment reduced Aβ production in cell culture and transgenic (Tg2576 and 3XTg-AD) mouse models, we next hypothesized that reduction of Aβ pathology might correlate with decreased microglial CD40 expression and/or increased phagocytosis by microglia.