Interactions between peripheral blood CD8 T lymphocytes and intestinal epithelial cells (iEC)

Clin Exp Immunol. 1998 May;112(2):226-36. doi: 10.1046/j.1365-2249.1998.00566.x.


Intestinal intraepithelial lymphocytes (iIEL) are primarily CD8 cells and most of them have a CD28- phenotype, the phenotype of effector cytotoxic T cells. We asked whether the predominance of CD8+CD28- T cells in the gut may result from peripheral blood T cells preferentially migrating to the iIEL compartment and adhering to iEC. Compared with CD4 cells, adhesion of resting CD8+ T cells to iEC cell lines was significantly higher. Adhesion could be blocked with a MoAb to gp180, a molecule expressed on iEC which is known to interact with CD8/lck. No significant difference in the level of adhesion was observed between CD8+CD28+ and CD8+CD28- T cells. Thus CD8 cells may preferentially migrate to the iIEL compartment, but loss of CD28 expression could occur in situ after migration. Consistent with this hypothesis, the CD8+CD28- cells became enriched after co-culturing T cells with iEC cell lines and primary iEC. Induction of the CD8+CD28- phenotype in cord blood and adult T cells was observed in co-cultures with iEC and also with mitogens and superantigens. In the latter case, CD28 down-modulation was seen specifically in the Vbeta subset targeted by the superantigen, indicating that loss of CD28 expression is a direct result of T cell receptor (TCR)-mediated stimulation. The combined results suggest that CD8+CD28- T cells are antigen experienced T cells, and that they may have a survival advantage in the presence of gut epithelial cells in vitro. This may contribute to the predominance of CD8+CD28- T cells in the iIEL compartment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • CD28 Antigens / analysis
  • CD8-Positive T-Lymphocytes / cytology
  • CD8-Positive T-Lymphocytes / immunology*
  • Cell Adhesion
  • Cell Compartmentation
  • Cell Death / immunology
  • Cells, Cultured
  • Coculture Techniques
  • Fetal Blood
  • Humans
  • Intestinal Mucosa / cytology
  • Intestinal Mucosa / immunology*
  • T-Lymphocytes, Cytotoxic / immunology


  • CD28 Antigens