Elevated numbers of SCART1+ gammadelta T cells in skin inflammation and inflammatory bowel disease

Mol Immunol. 2010 May;47(9):1710-8. doi: 10.1016/j.molimm.2010.03.002. Epub 2010 Apr 8.

Abstract

The members of the scavenger receptor cysteine-rich (SRCR) superfamily group B have diverse functions, including roles in the immune system. For years it has been known that the WC1 protein is expressed on the surface of bovine gammadelta T cells, and more recent studies indicate that WC1(+) gammadelta T cells respond to stimulation with bacterial antigens by producing interferon-gamma. The SRCR proteins CD5, CD6, Sp alpha, CD163, and DMBT1/gp-340 are also involved in the immune response, since they are pattern recognition receptors capable of binding directly to bacterial and/or fungal components. Here, we investigate a novel murine SRCR protein named SCART1. The ectodomain and the full-length SCART1 were expressed in mammalian cells and used to raise monoclonal antibodies against the ectodomain for immunohistochemical and FACS analysis. Immunohistochemical analysis shows that SCART1 is expressed in a range of lymphoid organs and epithelial-rich tissues by a subset of T cells identified as being gammadelta T cells by FACS analysis. SCART1 was present in 86% of the gammadelta T cells and was not found in CD4(+) or CD8(+) T cells. The numbers of SCART1(+) cells were elevated in two mouse models of human diseases: skin inflammation and inflammatory bowel disease. In the skin inflammation model, an 8.6-fold increase in SCART1(+) cells was observed. Finally, recombinant SCART1 protein was found not to bind to selected bacterial or fungal components or to whole bacteria. Our results show that SCART1 is a novel gammadelta T cell marker and it is therefore likely that SCART1 plays a role in the immune response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibody Specificity / immunology
  • Blotting, Western
  • CHO Cells
  • Cell Line
  • Cricetinae
  • Cricetulus
  • Dermatitis / immunology*
  • Dermatitis / metabolism
  • Dermatitis / pathology
  • Flow Cytometry
  • Humans
  • Immunohistochemistry
  • Inflammatory Bowel Diseases / immunology*
  • Inflammatory Bowel Diseases / metabolism
  • Inflammatory Bowel Diseases / pathology
  • Membrane Proteins / immunology
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred DBA
  • Protein Binding
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Antigen, T-Cell, gamma-delta / immunology*
  • Receptors, Antigen, T-Cell, gamma-delta / metabolism
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / immunology*
  • Receptors, Cell Surface / metabolism
  • Recombinant Proteins / immunology
  • Recombinant Proteins / metabolism
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism
  • T-Lymphocytes / pathology
  • Transfection

Substances

  • Antibodies, Monoclonal
  • Membrane Proteins
  • Receptors, Antigen, T-Cell, gamma-delta
  • Receptors, Cell Surface
  • Recombinant Proteins
  • SCART1 protein, mouse