Old receptor, new tricks—The ever-expanding universe of aryl hydrocarbon receptor functions. Report from the 4th AHR meeting, 29–31 August 2018 in Paris, France

In a time where “translational” science has become a mantra in the biomedical field, it is reassuring when years of research into a biological phenomenon suddenly points towards novel prevention or therapeutic approaches to disease, thereby demonstrating once again that basic science and translational science are intimately linked. The studies on the aryl hydrocarbon receptor (AHR) discussed here provide a perfect example of how years of basic toxicological research on a molecule, whose normal physiological function remained a mystery for so long, has now yielded a treasure trove of actionable information on the development of targeted therapeutics. Examples are autoimmunity, metabolic imbalance, inflammatory skin and gastro-intestinal diseases, cancer, development and perhaps ageing. Indeed, the AHR field no longer asks, “What does this receptor do in the absence of xenobiotics?” It now asks, “What doesn’t this receptor do?”.