The majority of contacts with foreign antigenic materials occur on the gut mucosa, and are represented by food proteins and the autochthonous microbiota. In the present study, we replaced intact dietary proteins by equivalent amounts of amino acids from weaning on and investigated its effects on the development of the immune system of mice. Adult animals reared on a balanced protein-free diet (...

The murine gut epithelium contains a large population of thymus-derived intraepithelial lymphocytes (IELs), including both conventional CD4 and CD8 T cells (expressing T-cell receptor [TCR ]) and unconventional CD8 T cells (expressing either TCR or TCR ). Whereas conventional IELs are widely accepted to arise from recirculation of activated CD4 and CD8 T cells from the secondary lymphoid organs...

Murine Butyrophilin-like (Btnl) 1 and Btnl6 are primarily restricted to intestinal epithelium where they regulate the function of intraepithelial T lymphocytes. We recently demonstrated that Btnl1 and Btnl6 can form an intra-family heterocomplex and that the Btnl1-Btnl6 complex selectively expands Vγ7Vδ4 TCR IELs. To define the regulation of Btnl expression in the small intestine during ontogen...

The kinase TAK is required for the development of conventional and regulatory T cells. We previously reported that mice with conditional deletion of TAK1 in T cells (Lck-cre:TAK1fl/fl mice) exhibited severe T lymphopenia, and were nevertheless predisposed to spontaneous colitis with unknown etiology. Here we focused on the immunopathological mechanism in colitic Lck-cre:TAK1fl/fl mice. We found...

O ver the last few years, the characterization of T lyraphocytes within the intestinal epithelium (ilEL) has revealed phenotypic and functional heterogeneity that rivals only that observed within the thymus. Of note in this context is that thymic and intestinal epithdia share the same embryologic origin in that they are both derived from endoderm. Several lines of evidence have led to the concl...