Springer Seminars in Immunopathology

, Volume 26, Issue 3, pp 221–229

Plasmacytoid dendritic cell precursors/type I interferon-producing cells sense viral infection by Toll-like receptor (TLR) 7 and TLR9

Original Article

DOI: 10.1007/s00281-004-0180-4

Cite this article as:
Ito, T., Wang, YH. & Liu, YJ. Springer Semin Immun (2005) 26: 221. doi:10.1007/s00281-004-0180-4


Plasmacytoid dendritic cell (pDC) precursors, also called type I IFN (α/β/ω)-producing cells (IPCs), are the key effectors in the innate immune system because of their extraordinary capacity to produce type I IFNs against microbial infection, particularly viral infection. In contrast to myeloid DCs, human pDC/IPCs selectively express Toll-like receptor (TLR) 7 and TLR9 within the endosomal compartment. These receptors are specifically designed to recognize the nucleoside-based products derived from RNA viruses and DNA viruses. Therefore, this expression profile potentially enables pDC/IPCs to sense a variety of viruses. Stimulation of TLR7 or TLR9 leads to type I IFN responses through the MyD88 pathway. Thus, pDC/IPCs may play a central role in host defense against viral infection through the TLR7 and TLR9 system.


Innate immunitySingle-stranded RNACpG DNAMyD88Anti-viral immunity

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  1. 1.Department of Immunology and CCIRThe University of Texas, M. D. Anderson Cancer CenterHoustonUSA