EZH2 Represses the B Cell Transcriptional Program and Regulates Antibody-Secreting Cell Metabolism and Antibody Production

J Immunol. 2018 Feb 1;200(3):1039-1052. doi: 10.4049/jimmunol.1701470. Epub 2017 Dec 29.

Abstract

Epigenetic remodeling is required during B cell differentiation. However, little is known about the direct functions of epigenetic enzymes in Ab-secreting cells (ASC) in vivo. In this study, we examined ASC differentiation independent of T cell help and germinal center reactions using mice with inducible or B cell-specific deletions of Ezh2 Following stimulation with influenza virus or LPS, Ezh2-deficient ASC poorly proliferated and inappropriately maintained expression of inflammatory pathways, B cell-lineage transcription factors, and Blimp-1-repressed genes, leading to fewer and less functional ASC. In the absence of EZH2, genes that normally gained histone H3 lysine 27 trimethylation were dysregulated and exhibited increased chromatin accessibility. Furthermore, EZH2 was also required for maximal Ab secretion by ASC, in part due to reduced mitochondrial respiration, impaired glucose metabolism, and poor expression of the unfolded-protein response pathway. Together, these data demonstrate that EZH2 is essential in facilitating epigenetic changes that regulate ASC fate, function, and metabolism.

Publication types

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

MeSH terms

  • Animals
  • Antibody Formation / genetics
  • Antibody Formation / immunology*
  • B-Lymphocytes / cytology
  • B-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / immunology
  • Cell Differentiation / immunology
  • Cell Proliferation
  • Chromatin / physiology
  • Enhancer of Zeste Homolog 2 Protein / genetics*
  • Enhancer of Zeste Homolog 2 Protein / metabolism
  • Epigenesis, Genetic / genetics
  • Germinal Center / immunology
  • Histones / metabolism
  • Lipopolysaccharides / immunology
  • Lymphocyte Activation / immunology*
  • Methylation
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Orthomyxoviridae / immunology
  • Positive Regulatory Domain I-Binding Factor 1 / genetics
  • Transcription, Genetic / genetics*

Substances

  • Chromatin
  • Histones
  • Lipopolysaccharides
  • Prdm1 protein, mouse
  • Positive Regulatory Domain I-Binding Factor 1
  • Enhancer of Zeste Homolog 2 Protein
  • Ezh2 protein, mouse