Molecular Characterization of Human Plasmacytoid Dendritic Cells

Plasmacytoid dendritic cells (pDCs) represent a unique and important immune cell population capable of producing large quantifies of type I interferon (IFN) in response to viruses as well as nucleic acid-containing complexes from the host. These rare and mysterious cells have been revealed by in-depth molecular characterization. Several innate sensors and signaling molecules enriched in pDCs allow their specialized innate immune functions. In addition, human pDCs use a group of surface receptors that, through activation of a B-cell receptor (BCR)-like signaling pathway, modulate type I IFN responses. It is clear now that pDC development is influenced by distinctive transcription factors that specify a unique lineage. CD4(+)CD56(+) hematodermic neoplasm of human pDC origin has been revealed in explicit molecular terms. A detailed molecular description of pDCs helps us better define, understand, and track human pDCs in relation to their functions and physiological involvement.