IGHE and Alzheimer disease: Interestingly, AD is characterized by altered barrier function, additional loss-of-function mutation in filaggrin, and colonization by exotoxin-producing bacteria such as Staphylococcus aureus—where enterotoxins act as superantigens on polyclonal IgE production—while valid experimental models of AD need distinctive “neurodermatitis” features as well as sensory innervation, neurogenic skin inflammation, and AD-like skin lesions triggered by stress [101,102].