Dynamic regulation of T follicular regulatory cell responses by interleukin 2 during influenza infection

Nat Immunol. 2017 Nov;18(11):1249-1260. doi: 10.1038/ni.3837. Epub 2017 Sep 11.

Abstract

Interleukin 2 (IL-2) promotes Foxp3+ regulatory T (Treg) cell responses, but inhibits T follicular helper (TFH) cell development. However, it is not clear how IL-2 affects T follicular regulatory (TFR) cells, a cell type with properties of both Treg and TFH cells. Using an influenza infection model, we found that high IL-2 concentrations at the peak of the infection prevented TFR cell development by a Blimp-1-dependent mechanism. However, once the immune response resolved, some Treg cells downregulated CD25, upregulated Bcl-6 and differentiated into TFR cells, which then migrated into the B cell follicles to prevent the expansion of self-reactive B cell clones. Thus, unlike its effects on conventional Treg cells, IL-2 inhibits TFR cell responses.

MeSH terms

  • Animals
  • Cell Movement / genetics
  • Cell Movement / immunology
  • Forkhead Transcription Factors / genetics
  • Forkhead Transcription Factors / immunology
  • Forkhead Transcription Factors / metabolism
  • Gene Expression Profiling / methods
  • Host-Pathogen Interactions / drug effects
  • Host-Pathogen Interactions / immunology
  • Interleukin-2 / administration & dosage
  • Interleukin-2 / metabolism
  • Interleukin-2 / pharmacology*
  • Interleukin-2 Receptor alpha Subunit / genetics
  • Interleukin-2 Receptor alpha Subunit / metabolism
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Orthomyxoviridae / immunology*
  • Orthomyxoviridae / physiology
  • Orthomyxoviridae Infections / immunology*
  • Orthomyxoviridae Infections / metabolism
  • Orthomyxoviridae Infections / virology
  • Positive Regulatory Domain I-Binding Factor 1
  • Proto-Oncogene Proteins c-bcl-6 / genetics
  • Proto-Oncogene Proteins c-bcl-6 / metabolism
  • T-Lymphocytes, Helper-Inducer / drug effects*
  • T-Lymphocytes, Helper-Inducer / immunology
  • T-Lymphocytes, Helper-Inducer / metabolism
  • T-Lymphocytes, Regulatory / drug effects*
  • T-Lymphocytes, Regulatory / immunology
  • T-Lymphocytes, Regulatory / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / immunology
  • Transcription Factors / metabolism

Substances

  • Forkhead Transcription Factors
  • Foxp3 protein, mouse
  • Interleukin-2
  • Interleukin-2 Receptor alpha Subunit
  • Prdm1 protein, mouse
  • Proto-Oncogene Proteins c-bcl-6
  • Transcription Factors
  • Positive Regulatory Domain I-Binding Factor 1