Diminished effector and memory CD8+ circulating T lymphocytes in patients with severe influenza caused by the AH1N1 pdm09 virus

Virology. 2017 Jan:500:139-148. doi: 10.1016/j.virol.2016.10.016. Epub 2016 Nov 2.

Abstract

The T cell immune response to viral infection includes the expansion of naïve T cells, effector cell differentiation and the induction of long-lived memory cells. We compared the differentiation of CD8+ T cells in patients with severe or mild pneumonia induced by influenza infection occurring during the 2009 influenza outbreak and compared their T cell subsets with those in blood samples obtained from healthy volunteers before the AH1N1 influenza outbreak in Mexico. Patients with severe influenza exhibited significantly lower numbers of effector memory CD8+CD26 high CD45RO+CCR7+ phenotype and lower numbers of central memory CD8+CD26high CD62L+CCR7+, CD26 high CD62L+CD127+ or CD26 high CD45RO+CD57 low phenotypes than patients with mild influenza or unexposed healthy subjects. Effector T cells with CD8+CD26CD62L low CD57+ phenotype were significantly diminished in severe influenza patients compared to those in patients with mild influenza or unexposed healthy subjects. These results suggest that low levels of circulating CD8+ T effector and central memory cells are associated with influenza severity.

Keywords: H1N1pdm09 virus; Influenza severity; Memory CD8+ T lymphocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / virology
  • Humans
  • Immunologic Memory*
  • Influenza A Virus, H1N1 Subtype / genetics
  • Influenza A Virus, H1N1 Subtype / immunology*
  • Influenza A Virus, H1N1 Subtype / physiology
  • Influenza, Human / immunology*
  • Influenza, Human / virology
  • Mexico
  • T-Lymphocyte Subsets / immunology
  • T-Lymphocyte Subsets / virology