Aire-dependent production of XCL1 mediates medullary accumulation of thymic dendritic cells and contributes to regulatory T cell development. by Lei, Y, Ripen, A, Ishimaru, N, Ohigashi, I, Nagasawa, T, Jeker, LT, Bösl, MR, Holländer, G, Hayashi, Y, Malefyt, R, Nitta, T, Takahama, Y