IGHE and Alzheimer disease: LCs, IDECs, dermal inflammatory DCs, and plasmacytoid DCs have major histocompatibility complex class I and II molecules and can become immunoglobulin (Ig) E-bearing DCs with complexes of IgE and high-affinity receptor FcєRI in the major form of AD with IgE allergy (IgE-allergic (extrinsic form) AD) [1,3,4,5,6].