IFNG and listeriosis: T‐bet deficiency was found to significantly reduce IFNγ expression by peripheral γδ27+ T cells both in vitro and in vivo upon infection with murid herpes viruses, while also impairing IFNγ production by γδ27−CCR6+ T cells stimulated with IL‐1β or IL‐23 in vitro or during Listeria infection in vivo.86