Activation of the aryl hydrocarbon receptor reveals distinct requirements for IL-22 and IL-17 production by human T helper cells

作者：Ramirez Jean Marie; Brembilla Nicolo C; Sorg Olivier; Chicheportiche Rachel; Matthes Thomas; Dayer Jean Michel; Saurat Jean Hilaire; Roosnek Eddy; Chizzolini Carlo^*

来源：European Journal of Immunology, 2010, 40(9): 2450-2459.

DOI：10.1002/eji.201040461

• Aryl hydrocarbon receptor
• Dioxin
• IL-17
• IL-22
• T cells

Ligands of the aryl hydrocarbon receptor (AHR), a transcription factor mediating the effects of dioxin, favor Th17 differentiation and exacerbate autoimmunity in mice. We investigated how AHR ligands affected human T-cell polarization. We found that the high affinity and stable AHR-ligand dioxin as well as the natural AHR-ligand 6-formylinolo[3,2-b] carbazole induced the downstream AHR-target cytochrome P450A1, and without affecting IFN-gamma, they enhanced IL-22 while simultaneously decreasing IL-17A production by CD4(+) T cells. The specific AHR-inhibitor CH-223191 abolished these effects. Furthermore, blockade of IL-23 and IL-1, important for Th17 expansion, profoundly decreased IL-17A but not IL-22 production. AHR agonists reduced the expression of the Th17 master transcription factor retinoic acid-related orphan receptor C (RORC), without affecting T-bet, GATA-3 and Foxp3. They also decreased the expression of the IL-23 receptor. Importantly, AHR-ligation did not only decrease the number of Th17 cells but also primed naive CD4(+) T cells to produce IL-22 without IL-17 and IFN-gamma. Furthermore, IL-22 single producers did not express CD161, which distinguished them from the CD161(+) Th17 cells. Hence, our data provide compelling evidence that AHR activation participates in shaping human CD4(+) T-cell polarization favoring the emergence of a distinct subset of IL-22-producing cells that are independent from the Th17 lineage.

• 出版日期2010-9