By contrast, the Irf4 deficiency in CD11c+ cells results in impaired Th17 differentiation in the intestine and mesenteric LNs at the steady state or following intraperitoneal immunization with ovalbumin (OVA) with anti‐CD40 and LPS, as well as in the lung upon intranasal infection with Aspergillus fumigatus [43, 51]. Here, ITGAX is linked to infection.