IGHE and Alzheimer disease: We used BALB/c mice as a model animal because they exhibited symptoms very similar to those of human AD, including an increased IgE level and chronic dryness (Dearman et al., 1995), and 2,4-dinitrochlorobenzene (DNCB) was used to induce AD in BALB/c mice (Kim et al., 2014; Wang et al., 2015; Yoon et al., 2015).