Molecular characterization of human plasmacytoid dendritic cells.

Department of Immunology, Unit 901, 7455 Fannin, The University of Texas M D Anderson Cancer Center, Houston, TX 77030, USA.
Journal of Clinical Immunology (Impact Factor: 2.65). 04/2009; 29(3):257-64. DOI: 10.1007/s10875-009-9284-x
Source: PubMed

ABSTRACT INTRODUCTION: 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. CONCLUSION: A detailed molecular description of pDCs helps us better define, understand, and track human pDCs in relation to their functions and physiological involvement.

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    • "c o m / l o c a t e / y c i m m the unique immune properties of UCB, and open new avenues for improving UCB transplantation outcome. PDC selectively express Toll-like receptors 7 and 9 (TLR-7 and TLR-9), which are localized in the endosomal–lysosomal compartment and recognize unmethylated CpG motifs on viral RNA and DNA [19]. Upon activation by TLR-ligands, adult PDC rapidly secrete massive amounts of type I interferons (IFN) as well as chemokines that allow for the recruitment and the activation of immune cells. "
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