Antigen-independent differentiation and maintenance of effector-like resident memory T cells in tissues

J Immunol. 2012 May 15;188(10):4866-75. doi: 10.4049/jimmunol.1200402. Epub 2012 Apr 13.

Abstract

Differentiation and maintenance of recirculating effector memory CD8 T cells (T(EM)) depends on prolonged cognate Ag stimulation. Whether similar pathways of differentiation exist for recently identified tissue-resident effector memory T cells (T(RM)), which contribute to rapid local protection upon pathogen re-exposure, is unknown. Memory CD8αβ(+) T cells within small intestine epithelium are well-characterized examples of T(RM), and they maintain a long-lived effector-like phenotype that is highly suggestive of persistent Ag stimulation. This study sought to define the sources and requirements for prolonged Ag stimulation in programming this differentiation state, including local stimulation via cognate or cross-reactive Ags derived from pathogens, microbial flora, or dietary proteins. Contrary to expectations, we found that prolonged cognate Ag stimulation was dispensable for intestinal T(RM) ontogeny. In fact, chronic antigenic stimulation skewed differentiation away from the canonical intestinal T cell phenotype. Resident memory signatures, CD69 and CD103, were expressed in many nonlymphoid tissues including intestine, stomach, kidney, reproductive tract, pancreas, brain, heart, and salivary gland and could be driven by cytokines. Moreover, TGF-β-driven CD103 expression was required for T(RM) maintenance within intestinal epithelium in vivo. Thus, induction and maintenance of long-lived effector-like intestinal T(RM) differed from classic models of T(EM) ontogeny and were programmed through a novel location-dependent pathway that was required for the persistence of local immunological memory.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Differentiation / immunology*
  • Cell Line
  • Epitopes, T-Lymphocyte / physiology*
  • Female
  • Immunologic Memory / immunology*
  • Immunophenotyping
  • Intestinal Mucosa / immunology
  • Intestinal Mucosa / pathology
  • Intestinal Mucosa / virology
  • Lymphocytic choriomeningitis virus / immunology
  • Lymphocytic choriomeningitis virus / pathogenicity
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Organ Specificity / immunology
  • Signal Transduction / immunology
  • T-Lymphocyte Subsets / immunology*
  • T-Lymphocyte Subsets / pathology
  • T-Lymphocyte Subsets / virology
  • Time Factors
  • Tissue Distribution / immunology

Substances

  • Epitopes, T-Lymphocyte