CCR6-dependent recruitment of blood phagocytes is necessary for rapid CD4 T cell responses to local bacterial infection

Proc Natl Acad Sci U S A. 2007 Jul 17;104(29):12075-80. doi: 10.1073/pnas.0701363104. Epub 2007 Jul 5.

Abstract

The contribution of CCR6 and phagocyte recruitment to the initiation of T cell responses to a local pathogen is unclear. CD4 T cell activation to an injected soluble antigen occurred rapidly and was completely CCR6-independent. In marked contrast, the tempo of pathogen-specific CD4 T cell activation depended on whether the antigen was secreted or cell-associated. Furthermore, lymph node pathogen-specific CD4 T cell activation required CCR6 and cell migration from the site of infection. Surprisingly, adoptive transfer of wild-type blood phagocytes rescued bacteria-specific T cell activation in CCR6-deficient mice, even when these cells were unable to participate in direct antigen presentation. These data demonstrate that T cell responses to a local bacterial infection follow a distinct tempo, largely determined by bacterial protein secretion, and that CCR6-mediated blood phagocyte recruitment to the site of infection is a critical step in the initiation of pathogen-specific immune responses in skin draining lymph nodes.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adoptive Transfer
  • Animals
  • Antigen Presentation / immunology
  • Antigens, Bacterial / immunology
  • CD4-Positive T-Lymphocytes / cytology
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / microbiology
  • Cell Movement*
  • Cell Proliferation
  • Dendritic Cells / cytology
  • Inflammation
  • Kinetics
  • Lymph Nodes / cytology
  • Lymph Nodes / pathology
  • Lymphocyte Activation / immunology
  • Mice
  • Phagocytes / cytology*
  • Phagocytes / immunology*
  • Phagocytes / microbiology
  • Receptors, CCR6
  • Receptors, Chemokine / deficiency
  • Receptors, Chemokine / immunology*
  • Salmonella
  • Salmonella Infections / immunology*
  • Solubility

Substances

  • Antigens, Bacterial
  • CCR6 protein, mouse
  • Receptors, CCR6
  • Receptors, Chemokine