T cell calcium dynamics visualized in a ratiometric tdTomato-GCaMP6f transgenic reporter mouse
- University of California, Irvine, United States
Abstract
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 naïve T cells, helper Th17 T cells and regulatory T cells, and Ca2+ signals mediated in T cells by an activator of mechanosensitive Piezo1channels. 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.
Article and author information
Author details
Funding
National Institutes of Health (AI117555)
- Joseph L Dynes
- Michael D Cahalan
National Institutes of Health (NS14609)
- Michael D Cahalan
National Institutes of Health (AI121945)
- Michael D Cahalan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Use of blood samples from healthy human subjects has been approved by the University of California, Irvine Institutional Review Board (UCI IRB HS #1995-459). All animal procedures were approved by the UCI Institutional Animal Care and Use committee (IACUC) (protocol #1998-1366-11).
Human subjects: Human blood was prepared using support from the National Center for Research Resources and the National Center for Advancing Translational Sciences (NIH Grant UL1 TR000153).
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.
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T cell calcium dynamics visualized in a ratiometric tdTomato-GCaMP6f transgenic reporter mouse
eLife 6:e32417.
https://doi.org/10.7554/eLife.32417
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