T Cell Factor 1-Expressing Memory-like CD8(+) T Cells Sustain the Immune Response to Chronic Viral Infections

Immunity. 2016 Aug 16;45(2):415-27. doi: 10.1016/j.immuni.2016.07.021.

Abstract

Chronic infections promote the terminal differentiation (or "exhaustion") of T cells and are thought to preclude the formation of memory T cells. In contrast, we discovered a small subpopulation of virus-specific CD8(+) T cells that sustained the T cell response during chronic infections. These cells were defined by, and depended on, the expression of the transcription factor Tcf1. Transcriptome analysis revealed that this population shared key characteristics of central memory cells but lacked an effector signature. Unlike conventional memory cells, Tcf1-expressing T cells displayed hallmarks of an "exhausted" phenotype, including the expression of inhibitory receptors such as PD-1 and Lag-3. This population was crucial for the T cell expansion that occurred in response to inhibitory receptor blockade during chronic infection. These findings identify a memory-like T cell population that sustains T cell responses and is a prime target for therapeutic interventions to improve the immune response in chronic infections.

Keywords: LCMV; PD-1; T cell exhaustion; T cell memory; Tcf1; chronic infection; differentiation of cytotoxic T cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Antigens, CD / metabolism
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / virology
  • Cell Proliferation
  • Cells, Cultured
  • Cellular Senescence
  • Chronic Disease
  • Female
  • Hepacivirus / immunology*
  • Hepatitis C, Chronic / immunology*
  • Humans
  • Immunologic Memory
  • Immunotherapy / methods*
  • Lymphocyte Activation Gene 3 Protein
  • Lymphocytic Choriomeningitis / immunology*
  • Lymphocytic choriomeningitis virus / immunology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Middle Aged
  • Programmed Cell Death 1 Receptor / metabolism
  • T Cell Transcription Factor 1 / genetics
  • T Cell Transcription Factor 1 / metabolism*
  • Transcriptome

Substances

  • Antigens, CD
  • Pdcd1 protein, mouse
  • Programmed Cell Death 1 Receptor
  • T Cell Transcription Factor 1
  • Lymphocyte Activation Gene 3 Protein