AHR and bacterial infectious disease: Lack of AHR in intestinal eosinophils affects the local immune system and increases susceptibility to helminth infection, but whether it alters the microbiome or immune response to bacterial infection is not known.7,8 Because AHR is known to promote an anti-inflammatory phenotype in myeloid cells, it can be speculated that AHRR and its suppression of innate immune response genes is part of the broader AHR-mediated regulation of immune cells in barrier organs.