TLR2 and listeriosis: While production of IFN-β in response to Listeria infection is independent from TLRs in bone-marrow-derived macrophages (McCaffrey et al., 2004; Stockinger et al., 2004; O'Connell et al., 2005), TLR-2 contributes significantly to IFN-β secretion by peritoneal macrophages, suggesting that specific macrophage populations have evolved different recognition strategies in response to Listeria infection (Aubry et al., 2012).