Tissue Environment, Not Ontogeny, Defines Murine Intestinal Intraepithelial T Lymphocytes

To gain functional insights into these tissue-resident intestinal intraepithelial T lymphocytes, the authors used high-resolution, quantitative mass spectrometry to compare the proteomes of induced tissue-resident intestinal intraepithelial T lymphocytes (T-IEL) and natural T-IEL subsets, with naive CD8+ T cells from lymph nodes.