AHR and infection: To the best of our knowledge, none of the intracellular transcriptional regulation factors linked to TLR2-activated signaling pathways [6] has been related to regulation of CYP1A1, though it has become clear that both production of interleukin 22 by γδ T cells and their expansion depend on AHR availability [39] and mice that lack AHR are much more susceptible to infections with Toxoplasma gondii[40], suggesting a relevant role for AHR/ARNT signaling in immune response.