The number of intraepithelial T cells decreases from ascending colon to rectum
- J A Kirby1,
- M Bone1,
- H Robertson1,
- M Hudson2,
- D E J Jones2
- 1Applied Immunobiology Group, Medical School, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4HH, UK; j.a.kirby@ncl.ac.uk
- 2Centre for Liver Research, Medical School, University of Newcastle upon Tyne
The αEβ7-integrin (CD103) is expressed almost uniquely by T cells of the mucosal immune system, where it is upregulated on activated cells by the action of transforming growth factor β. The only known ligand for this integrin is E-cadherin,1 which is expressed by all epithelial cells, where it constitutes a homotypic adhesion system necessary for tight junction formation. A role for interaction between the αEβ7-integrin and E-cadherin in the localisation of intraepithelial T cells is supported by the reduction in numbers of mucosal T cells seen in CD103 deficient mice.2
The role of CD103+ T cells remains unclear. However, the potential of these cells to bind specifically to the epithelium is consistent with a capacity to mediate damage localised to this tissue. …
