Involvement of CD44v6 in InlB-dependent Listeria invasion

Mol Microbiol. 2009 Jun;72(5):1196-207. doi: 10.1111/j.1365-2958.2009.06716.x. Epub 2009 Apr 30.


Listeria monocytogenes, a Gram-positive bacterium, is the causative agent for the disease called listeriosis. This pathogen utilizes host cell surface proteins such as E-cadherin or c-Met in order to invade eukaryotic cells. The invasion via c-Met depends on the bacterial protein InlB that activates c-Met phosphorylation and internalization mimicking in many regards HGF, the authentic c-Met ligand. In this paper, we demonstrate that the activation of c-Met induced by InlB is dependent on CD44v6, a member of the CD44 family of transmembrane glycoproteins. Inhibiting CD44v6 by means of a blocking peptide, a CD44v6 antibody or CD44v6-specific siRNA prevents the activation of c-Met induced by InlB. Subsequently, signalling, scattering and the entry of InlB-coated beads into host cells are also impaired by CD44v6 blocking reagents. For the entry process, ezrin, a protein that links the CD44v6 cytoplasmic domain to the cytoskeleton, is required as well. Most importantly, this collaboration between c-Met and CD44v6 contributes to the invasion of L. monocytogenes into target cells as demonstrated by a drastic decrease in bacterial invasion in the presence of blocking agents such as the CD44v6 peptide or antibody.

MeSH terms

  • Animals
  • Bacterial Adhesion
  • Bacterial Proteins / immunology
  • Bacterial Proteins / metabolism*
  • Cytoskeletal Proteins / immunology
  • Cytoskeletal Proteins / metabolism
  • HeLa Cells
  • Humans
  • Hyaluronan Receptors / immunology
  • Hyaluronan Receptors / metabolism*
  • Listeriosis / immunology
  • Listeriosis / microbiology*
  • Membrane Proteins / immunology
  • Membrane Proteins / metabolism*
  • Proto-Oncogene Proteins c-met / immunology
  • Proto-Oncogene Proteins c-met / metabolism*
  • Rats


  • Bacterial Proteins
  • CD44v6 antigen
  • Cytoskeletal Proteins
  • Hyaluronan Receptors
  • Membrane Proteins
  • ezrin
  • inlB protein, Listeria monocytogenes
  • Proto-Oncogene Proteins c-met