IL4 and Alzheimer disease: In addition, mast cells (MCs) in allergic diseases including AD have shown playing a crucial role in the secretion of histamine, leukotrienes, prostaglandin D2, proteolytic enzymes, and several cytokines including interleukin- (IL-) 1β, IL-4, IL-6, tumor necrosis factor- (TNF-) α, and interferon- (IFN-) γ [4].