Plasmacytoid dendritic cells capture and cross-present viral antigens from influenza-virus exposed cells

PLoS One. 2009 Sep 22;4(9):e7111. doi: 10.1371/journal.pone.0007111.


Among the different subsets of dendritic cells (DC), plasmacytoid dendritic cells (PDC) play a unique role in secreting large amounts of type I interferons upon viral stimulation, but their efficiency as antigen-presenting cells has not been completely characterized. We show here, by flow cytometry, with human primary blood PDC and with a PDC cell line, that PDC display poor endocytic capacity for soluble or cellular antigens when compared to monocyte-derived myeloid DC. However, immature PDC efficiently take up cellular material from live influenza-exposed cells, subsequently mature and cross-present viral antigens very efficiently to specific CD8+ T cells. Therefore, during viral infection PDC not only secrete immunomodulatory cytokines, but also recognize infected cells and function as antigen cross-presenting cells to trigger the anti-viral immune response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigen Presentation / immunology
  • Antigen-Presenting Cells / immunology*
  • Antigens, Viral / immunology*
  • Antiviral Agents / pharmacology
  • CD8-Positive T-Lymphocytes / immunology
  • Cell Line, Tumor
  • Cytokines / immunology
  • Dendritic Cells / cytology*
  • Dendritic Cells / immunology
  • Dendritic Cells / virology*
  • Endocytosis
  • Flow Cytometry / methods
  • Humans
  • Immunophenotyping
  • Interferon-alpha / metabolism
  • Lymphocyte Activation
  • Orthomyxoviridae / metabolism*


  • Antigens, Viral
  • Antiviral Agents
  • Cytokines
  • Interferon-alpha