Vimentin expressed on Mycobacterium tuberculosis-infected human monocytes is involved in binding to the NKp46 receptor

J Immunol. 2006 Nov 1;177(9):6192-8. doi: 10.4049/jimmunol.177.9.6192.

Abstract

We previously showed that human NK cells used the NKp46 receptor to lyse Mycobacterium tuberculosis H37Ra-infected monocytes. To identify ligands on H37Ra-infected human mononuclear phagocytes, we used anti-NKp46 to immunoprecipitate NKp46 from NK cells bound to its ligand(s) on H37Ra-infected monocytes. Mass spectrometry analysis identified a 57-kDa molecule, vimentin, as a putative ligand for NKp46. Vimentin expression was significantly up-regulated on the surface of infected monocytes, compared with uninfected cells, and this was confirmed by fluorescence microscopy. Anti-vimentin antiserum inhibited NK cell lysis of infected monocytes, whereas antiserum to actin, another filamentous protein, did not. CHO-K1 cells transfected with a vimentin construct were lysed much more efficiently by NK cells than cells transfected with a control plasmid. This lysis was inhibited by mAb-mediated masking of NKp46 (on NK cells) or vimentin (on infected monocytes). ELISA and Far Western blotting showed that recombinant vimentin bound to a NKp46 fusion protein. These results indicate that vimentin is involved in binding of NKp46 to M. tuberculosis H37Ra-infected mononuclear phagocytes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies / pharmacology
  • Blotting, Far-Western
  • CHO Cells
  • Cell Membrane / chemistry
  • Cricetinae
  • Cricetulus
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoprecipitation
  • Killer Cells, Natural / drug effects
  • Killer Cells, Natural / immunology
  • Ligands
  • Monocytes / chemistry
  • Monocytes / metabolism
  • Monocytes / microbiology*
  • Mycobacterium tuberculosis / immunology*
  • Natural Cytotoxicity Triggering Receptor 1
  • Phagocytes / chemistry
  • Phagocytes / metabolism
  • Phagocytes / microbiology
  • Phagocytosis / drug effects
  • Protein Interaction Mapping
  • Receptors, Immunologic / metabolism*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Vimentin / analysis*
  • Vimentin / antagonists & inhibitors
  • Vimentin / metabolism*

Substances

  • Antibodies
  • Ligands
  • NCR1 protein, human
  • Natural Cytotoxicity Triggering Receptor 1
  • Receptors, Immunologic
  • Recombinant Fusion Proteins
  • Vimentin