We investigated the relationship between S. aureus skin colonization, IL-4, and food allergy in a mouse model of AD elicited by epicutaneous sensitization with antigen in which oral antigen challenge results in IgE-mediated anaphylaxis.47,48 Sensitization to antigen in the presence of superantigen-producing S. aureus, or SEB, caused elevation of serum IL-4 concentrations and exaggerated oral anaphylaxis compared with sensitization with antigen alone. The gene discussed is IGHE; the disease is Alzheimer disease.