Aryl hydrocarbon receptor activation increases survival in polymicrobial sepsis

Sepsis is a systemic inflammatory response resulting from the inability of the host to restrict the infection locally. Studies realized in our laboratory demonstrated that the high mortality observed in severe sepsis (S-CLP) correlates with the failure of the neutrophil migration to infectious focus and infection dissemination. However, animals subjected to a model of local infection (NS-CLP) present an efficient neutrophil recruitment that constrains the spreading of infection. In this context, we demonstrated a direct action of IL-17 mediating the neutrophil recruitment [1]. Recently, it was demonstrated that aryl hydrocarbon receptor (AhR) activation has a role in immune response. The AhR is expressed by Th17 cells and also by innate immune system cells and is important for their effectors functions, including IL-17 and IL-22 production [2]. However, the function of the AhR in sepsis remains uncertain. Herein, we investigate the role of AhR in polymicrobial sepsis induced by cecal ligation and puncture (CLP).