Interferon-alpha subtype 11 activates NK cells and enables control of retroviral infection

PLoS Pathog. 2012;8(8):e1002868. doi: 10.1371/journal.ppat.1002868. Epub 2012 Aug 9.


The innate immune response mediated by cells such as natural killer (NK) cells is critical for the rapid containment of virus replication and spread during acute infection. Here, we show that subtype 11 of the type I interferon (IFN) family greatly potentiates the antiviral activity of NK cells during retroviral infection. Treatment of mice with IFN-α11 during Friend retrovirus infection (FV) significantly reduced viral loads and resulted in long-term protection from virus-induced leukemia. The effect of IFN-α11 on NK cells was direct and signaled through the type I IFN receptor. Furthermore, IFN-α11-mediated activation of NK cells enabled cytolytic killing of FV-infected target cells via the exocytosis pathway. Depletion and adoptive transfer experiments illustrated that NK cells played a major role in successful IFN-α11 therapy. Additional experiments with Mouse Cytomegalovirus infections demonstrated that the therapeutic effect of IFN-α11 is not restricted to retroviruses. The type I IFN subtypes 2 and 5, which bind the same receptor as IFN-α11, did not elicit similar antiviral effects. These results demonstrate a unique and subtype-specific activation of NK cells by IFN-α11.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Female
  • Friend murine leukemia virus / immunology*
  • HEK293 Cells
  • Humans
  • Interferon-alpha / immunology*
  • Killer Cells, Natural / immunology*
  • Lymphocyte Activation*
  • Mice
  • Mice, Inbred BALB C
  • Receptor, Interferon alpha-beta / immunology
  • Retroviridae Infections / immunology*
  • Signal Transduction / immunology


  • Interferon-alpha
  • Receptor, Interferon alpha-beta

Grant support

This work was supported by the German Research Association (GRK 1045). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.