Recently, a population of DC expressing CD11b+ CD11c+ LY-6C+ MHC-II+ and high levels of iNOS protein (termed inflammatory DC or TNF-iNOS-producing DC (Tip-DC)) [22],[23] has been implicated in the resistance to infection by intracellular bacteria (e.g. Listeria monocytogenes[22] and Brucella melitensis) [24]. Here, TNF is linked to infection.