Dendritic cells: From ontogenetic orphans to myelomonocytic descendants

Although dendritic cells (DCs) and macrophages share a bone marrow origin, these cells were long assumed to differentiate via discrete pathways. DCs have now been clearly shown to develop from myeloid lineage precursors, and recent evidence suggests that they may even differentiate from blood monocytes. Here, J. Hinrich Peters and colleagues assess current knowledge on the myelomonocytic origin and successive differentiation of human T-cell-directed DCs.