CD4 + T cell help creates memory CD8 + T cells with innate and help-independent recall capacities

Nat Commun. 2019 Dec 4;10(1):5531. doi: 10.1038/s41467-019-13438-1.

Abstract

CD4+ T cell help is required for the generation of CD8+ cytotoxic T lymphocyte (CTL) memory. Here, we use genome-wide analyses to show how CD4+ T cell help delivered during priming promotes memory differentiation of CTLs. Help signals enhance IL-15-dependent maintenance of central memory T (TCM) cells. More importantly, help signals regulate the size and function of the effector memory T (TEM) cell pool. Helped TEM cells produce Granzyme B and IFNγ upon antigen-independent, innate-like recall by IL-12 and IL-18. In addition, helped memory CTLs express the effector program characteristic of helped primary CTLs upon recall with MHC class I-restricted antigens, likely due to epigenetic imprinting and sustained mRNA expression of effector genes. Our data thus indicate that during priming, CD4+ T cell help optimizes CTL memory by creating TEM cells with innate and help-independent antigen-specific recall capacities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Cells, Cultured
  • Female
  • Granzymes / immunology
  • Granzymes / metabolism
  • Histocompatibility Antigens Class I / immunology
  • Histocompatibility Antigens Class I / metabolism
  • Immunologic Memory / immunology*
  • Interferon-gamma / immunology
  • Interferon-gamma / metabolism
  • Interleukin-12 / immunology
  • Interleukin-12 / metabolism
  • Lymphocyte Activation / immunology
  • Male
  • Mice
  • T-Lymphocytes, Cytotoxic / immunology
  • T-Lymphocytes, Cytotoxic / metabolism
  • Vaccines, DNA / immunology*

Substances

  • Histocompatibility Antigens Class I
  • Vaccines, DNA
  • Interleukin-12
  • Interferon-gamma
  • Granzymes