• atopy;
  • beta-adrenergic receptor;
  • IgE;
  • IL-4;
  • atopic dermatitis;
  • asthma

Several decades ago, Ingram already complained that “Atopy means exactly nothing, except in the mind of Coca and Cooke”. Despite very substantial progress in basic and clinical research on the atopic diseases, particularly in the areas of immunogenetics, cellular immunology and immunopharmacology, there is still a great deal of uncertainty, confusion and conflict on what exactly the basic underlying abnormality of the atopic diseases may be. Therefore, this inaugural feature of Controversies in Experimental Dermatology illustrates the ongoing dispute on one of the unsolved key problems of experimental and clinical dermatology, and sketches promising avenues for future research.