What lies beneath: Antibody dependent natural killer cell activation by antibodies to internal influenza virus proteins

Hillary A. Vanderven, Fernanda Ana-Sosa-Batiz, Sinthujan Jegaskanda, Steven Rockman, Karen Laurie, Ian Barr, Weisan Chen, Bruce Wines, P. Mark Hogarth, Teresa Lambe, Sarah C. Gilbert, Matthew S. Parsons, Stephen J. Kent

Research output: Contribution to journalArticleResearchpeer-review

41 Citations (Scopus)


The conserved internal influenza proteins nucleoprotein (NP) and matrix 1 (M1) are well characterised for T cell immunity, but whether they also elicit functional antibodies capable of activating natural killer (NK) cells has not been explored. We studied NP and M1-specific ADCC activity using biochemical, NK cell activation and killing assays with plasma from healthy and influenza-infected subjects. Healthy adults had antibodies to M1 and NP capable of binding dimeric FcγRIIIa and activating NK cells. Natural symptomatic and experimental influenza infections resulted in a rise in antibody dependent NK cell activation post-infection to the hemagglutinin of the infecting strain, but changes in NK cell activation to M1 and NP were variable. Although antibody dependent killing of target cells infected with vaccinia viruses expressing internal influenza proteins was not detected, opsonising antibodies to NP and M1 likely contribute to an antiviral microenvironment by stimulating innate immune cells to secrete cytokines early in infection. We conclude that effector cell activating antibodies to conserved internal influenza proteins are common in healthy and influenza-infected adults. Given the significance of such antibodies in animal models of heterologous influenza infection, the definition of their importance and mechanism of action in human immunity to influenza is essential.

Original languageEnglish
Pages (from-to)277-290
Number of pages14
Publication statusPublished - 1 Jun 2016


  • Antibody dependent cellular cytotoxicity
  • Hemagglutinin
  • Influenza
  • Matrix protein 1
  • Natural killer cells
  • Nucleoprotein

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