Activated human T cells secrete exosomes that participate in IL-2 mediated immune response signaling

PLoS One. 2012;7(11):e49723. doi: 10.1371/journal.pone.0049723. Epub 2012 Nov 16.

Abstract

It has previously been shown that nano-meter sized vesicles (30-100 nm), exosomes, secreted by antigen presenting cells can induce T cell responses thus showing the potential of exosomes to be used as immunological tools. Additionally, activated CD3⁺ T cells can secrete exosomes that have the ability to modulate different immunological responses. Here, we investigated what effects exosomes originating from activated CD3⁺ T cells have on resting CD3⁺ T cells by studying T cell proliferation, cytokine production and by performing T cell and exosome phenotype characterization. Human exosomes were generated in vitro following CD3⁺ T cell stimulation with anti-CD28, anti-CD3 and IL-2. Our results show that exosomes purified from stimulated CD3⁺ T cells together with IL-2 were able to generate proliferation in autologous resting CD3⁺ T cells. The CD3⁺ T cells stimulated with exosomes together with IL-2 had a higher proportion of CD8⁺ T cells and had a different cytokine profile compared to controls. These results indicate that activated CD3⁺ T cells communicate with resting autologous T cells via exosomes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD3 Complex / metabolism
  • CD8-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / metabolism
  • Cell Proliferation
  • Cells, Cultured
  • Cytokines / immunology
  • Cytokines / metabolism
  • Exosomes / metabolism*
  • Humans
  • Interleukin-2 / metabolism*
  • Interleukin-2 / pharmacology
  • Lymphocyte Activation / immunology*
  • Signal Transduction*
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism*

Substances

  • CD3 Complex
  • Cytokines
  • Interleukin-2

Grant support

This work was supported by grants from the Swedish Research Council (www.vr.se), Åke Wiberg Foundation (www.ake-wiberg.com), Assar Gabrielsson Foundation (www.agfond.se). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.