Microbial colonization influences composition and T-cell receptor V beta repertoire of intraepithelial lymphocytes in rat intestine

Immunology. 1996 Dec;89(4):494-501. doi: 10.1046/j.1365-2567.1996.d01-783.x.


Studies in mice have shown that the composition of intestinal intraepithelial lymphocytes (IEL) may be markedly altered by gut microbial colonization. Such modulation was studied in a rat model by the use of germ-free and conventionalized animals from which IEL from the small intestine were isolated and analysed by flow cytometry. Conventionalization caused expansion as well as phenotypic alterations of T-cell receptor (TCR) alpha/beta + IEL in that the proportions of CD4+ and CD8 alpha beta + TCR alpha/beta + cells were increased, while the double negative (CD4- CD8-) fraction was reduced. microbial colonization also influenced the TCR V beta repertoire of CD8+ IEL in that the proportions of V beta 8.2+ and V beta 10+ cells were increased, whereas V beta 8.5+ and V beta 16+ cells were relatively decreased. Moreover, conventionalization influenced the levels of TCR cell surface expression in the same V beta subsets. Three-colour flow-cytometric analysis demonstrated that skewing of the V beta repertoire was most pronounced in the CD8 alpha alpha + subset, although the numerical increase of IEL mainly included the CD8 alpha beta + subset. In contrast to IEL, the TCR V beta repertoire in mesenteric lymph nodes was unchanged after intestinal colonization. These results confirm that TCR alpha/beta + IEL subpopulations respond dynamically to the microbial gut flora and suggest that their V beta repertoire can be shaped by luminal microbial antigens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Flow Cytometry
  • Germ-Free Life
  • Immunity, Mucosal
  • Intestinal Mucosa / immunology*
  • Intestinal Mucosa / microbiology*
  • Lymphocyte Activation
  • Male
  • Mesentery / immunology
  • Rats
  • Rats, Inbred Strains
  • Receptors, Antigen, T-Cell, alpha-beta / immunology*
  • T-Lymphocytes / immunology*


  • Receptors, Antigen, T-Cell, alpha-beta