IGHE and allergic disease: Tissue targets are strategically located as barriers against the environment, and the sensitization of mast cells to antigens by antigen-specific IgE antibodies may be one of the many mechanisms, including those of both innate and adaptive immunity that have evolved to impede the entry of pathogens or toxins into the body and thus avert worse mayhem than that generally caused by mere allergic reactions (Galli et al., 1999, 2008; Palm et al., 2012).