DLL4 and psoriasis: Because mechanistic studies that induce DLL4 in DCs are important for better defining the ontogeny of DLL4+ DCs and targeting these cells for immunotherapy (24), the discovery of the induction method of DLL4-expressing cells (Figure 7) may contribute to devising a novel strategy using the cells or signaling pathways through such as DLL4, TGF-β1, IL-4, or langerin for human patients with autoinflammatory immune diseases such as psoriasis (24, 35, 58, 59).