1. Cell Biology
  2. Immunology and Inflammation
Download icon

Intermittent Ca2+ signals mediated by Orai1 regulate basal T cell motility

Research Article
  • Cited 2
  • Views 1,435
  • Annotations
Cite this article as: eLife 2017;6:e27827 doi: 10.7554/eLife.27827

Abstract

Ca2+ influx through Orai1 channels is crucial for several T cell functions, but a role in regulating basal cellular motility has not been described. Here we show that inhibition of Orai1 channel activity increases average cell velocities by reducing the frequency of pauses in human T cells migrating through confined spaces, even in the absence of extrinsic cell contacts or antigen recognition. Utilizing a novel ratiometric genetically encoded cytosolic Ca2+ indicator, Salsa6f, which permits real-time monitoring of cytosolic Ca2+ along with cell motility, we show that spontaneous pauses during T cell motility in vitro and in vivo coincide with episodes of cytosolic Ca2+ signaling. Furthermore, lymph node T cells exhibited two types of spontaneous Ca2+ transients: short-duration 'sparkles' and longer duration global signals. Our results demonstrate that spontaneous and self-peptide MHC-dependent activation of Orai1 ensures random walk behavior in T cells to optimize immune surveillance.

Article and author information

Author details

  1. Tobias X Dong

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5500-7099
  2. Shivashankar Othy

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6832-5547
  3. Milton L Greenberg

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Amit Jairaman

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Chijioke Akunwafo

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Sabrina Leverrier

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Ying Yu

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Ian Parker

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Joseph L Dynes

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Michael D Cahalan

    Department of Physiology and Biophysics, University of California, Irvine, Irvine, United States
    For correspondence
    mcahalan@uci.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4987-2526

Funding

National Institutes of Health (NS-14609)

  • Michael D Cahalan

National Science Foundation (IGERT DGE-1144901)

  • Tobias X Dong

National Institutes of Health (AI-121945)

  • Michael D Cahalan

National Institutes of Health (GM-41514)

  • Michael D Cahalan

National Institutes of Health (Training Grant T32-AI-060573)

  • Milton L Greenberg

National Institutes of Health (Training Grant T32-GM-008620)

  • Tobias X Dong

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All surgical procedures and animal maintenance complied with the National Institute of Health guidelines regarding the care and use of experimental animals and were approved by the Animal Care and Use Committee of University of California, Irvine (protocol 1998-1366).

Human subjects: All studies using human blood were approved by the University of California, Irvine Institutional Review Board (UCI IRB HS# 1995-460), and complied with all applicable UCI Research Policies for the conduct of human subjects research.

Reviewing Editor

  1. Michael L Dustin, University of Oxford, United Kingdom

Publication history

  1. Received: April 15, 2017
  2. Accepted: November 6, 2017
  3. Accepted Manuscript published: December 14, 2017 (version 1)
  4. Version of Record published: December 29, 2017 (version 2)

Copyright

© 2017, Dong et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 1,435
    Page views
  • 220
    Downloads
  • 2
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, Scopus, PubMed Central.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)

Further reading

    1. Cell Biology
    2. Immunology and Inflammation
    Tobias X Dong et al.
    Tools and Resources Updated

    Calcium is an essential cellular messenger that regulates numerous functions in living organisms. Here, we describe development and characterization of ‘Salsa6f’, a fusion of GCaMP6f and tdTomato optimized for cell tracking while monitoring cytosolic Ca2+, and a transgenic Ca2+ reporter mouse with Salsa6f targeted to the Rosa26 locus for Cre-dependent expression in specific cell types. The development and function of T cells was unaffected in Cd4-Salsa6f mice. We describe Ca2+ signals reported by Salsa6f during T cell receptor activation in naive T cells, helper Th17 T cells and regulatory T cells, and Ca2+ signals mediated in T cells by an activator of mechanosensitive Piezo1 channels. Transgenic expression of Salsa6f enables ratiometric imaging of Ca2+ signals in complex tissue environments found in vivo. Two-photon imaging of migrating T cells in the steady-state lymph node revealed both cell-wide and localized sub-cellular Ca2+ transients (‘sparkles’) as cells migrate.

    1. Cell Biology
    2. Neuroscience
    Sheena A Josselyn
    Feature Article