A new approach for ratiometric in vivo calcium imaging of microglia
Brawek, Bianca ; Liang, Yajie ; Savitska, Daria ; Li, Kaizhen ; Fomin-Thunemann, Natalie ; Kovalchuk, Yury ; Zirdum, Elizabeta ; Jakobsson, Johan LU
and Garaschuk, Olga
(2017)
In Scientific Reports
7(1).
- Abstract
Microglia, resident immune cells of the brain, react to the presence of pathogens/danger signals with a large repertoire of functional responses including morphological changes, proliferation, chemotaxis, production/release of cytokines, and phagocytosis. In vitro studies suggest that many of these effector functions are Ca2+-dependent, but our knowledge about in vivo Ca2+ signalling in microglia is rudimentary. This is mostly due to technical reasons, as microglia largely resisted all attempts of in vivo labelling with Ca2+ indicators. Here, we introduce a novel approach, utilizing a microglia-specific microRNA-9-regulated viral vector, enabling the expression of a genetically-encoded ratiometric... (More)
Microglia, resident immune cells of the brain, react to the presence of pathogens/danger signals with a large repertoire of functional responses including morphological changes, proliferation, chemotaxis, production/release of cytokines, and phagocytosis. In vitro studies suggest that many of these effector functions are Ca2+-dependent, but our knowledge about in vivo Ca2+ signalling in microglia is rudimentary. This is mostly due to technical reasons, as microglia largely resisted all attempts of in vivo labelling with Ca2+ indicators. Here, we introduce a novel approach, utilizing a microglia-specific microRNA-9-regulated viral vector, enabling the expression of a genetically-encoded ratiometric Ca2+ sensor Twitch-2B in microglia. The Twitch-2B-assisted in vivo imaging enables recording of spontaneous and evoked microglial Ca2+ signals and allows for the first time to monitor the steady state intracellular Ca2+ levels in microglia. Intact in vivo microglia show very homogenous and low steady state intracellular Ca2+ levels. However, the levels increase significantly after acute slice preparation and cell culturing along with an increase in the expression of activation markers CD68 and IL-1β. These data identify the steady state intracellular Ca2+ level as a versatile microglial activation marker, which is highly sensitive to the cell's environment.
(Less)
- author
- Brawek, Bianca
; Liang, Yajie
; Savitska, Daria
; Li, Kaizhen
; Fomin-Thunemann, Natalie
; Kovalchuk, Yury
; Zirdum, Elizabeta
; Jakobsson, Johan
LU
and Garaschuk, Olga
- organization
- publishing date
- 2017-12-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Scientific Reports
- volume
- 7
- issue
- 1
- article number
- 6030
- publisher
- Nature Publishing Group
- external identifiers
-
- pmid:28729628
- wos:000405907800084
- scopus:85025445357
- ISSN
- 2045-2322
- DOI
- 10.1038/s41598-017-05952-3
- language
- English
- LU publication?
- yes
- id
- 9308d5f2-10ff-42e7-b0b9-dba61789eb7f
- date added to LUP
- 2017-11-22 08:22:24
- date last changed
- 2025-01-08 00:56:42
@article{9308d5f2-10ff-42e7-b0b9-dba61789eb7f,
abstract = {{<p>Microglia, resident immune cells of the brain, react to the presence of pathogens/danger signals with a large repertoire of functional responses including morphological changes, proliferation, chemotaxis, production/release of cytokines, and phagocytosis. In vitro studies suggest that many of these effector functions are Ca<sup>2+</sup>-dependent, but our knowledge about in vivo Ca<sup>2+</sup> signalling in microglia is rudimentary. This is mostly due to technical reasons, as microglia largely resisted all attempts of in vivo labelling with Ca<sup>2+</sup> indicators. Here, we introduce a novel approach, utilizing a microglia-specific microRNA-9-regulated viral vector, enabling the expression of a genetically-encoded ratiometric Ca<sup>2+</sup> sensor Twitch-2B in microglia. The Twitch-2B-assisted in vivo imaging enables recording of spontaneous and evoked microglial Ca<sup>2+</sup> signals and allows for the first time to monitor the steady state intracellular Ca<sup>2+</sup> levels in microglia. Intact in vivo microglia show very homogenous and low steady state intracellular Ca<sup>2+</sup> levels. However, the levels increase significantly after acute slice preparation and cell culturing along with an increase in the expression of activation markers CD68 and IL-1β. These data identify the steady state intracellular Ca<sup>2+</sup> level as a versatile microglial activation marker, which is highly sensitive to the cell's environment.</p>}},
author = {{Brawek, Bianca and Liang, Yajie and Savitska, Daria and Li, Kaizhen and Fomin-Thunemann, Natalie and Kovalchuk, Yury and Zirdum, Elizabeta and Jakobsson, Johan and Garaschuk, Olga}},
issn = {{2045-2322}},
language = {{eng}},
month = {{12}},
number = {{1}},
publisher = {{Nature Publishing Group}},
series = {{Scientific Reports}},
title = {{A new approach for ratiometric in vivo calcium imaging of microglia}},
url = {{http://dx.doi.org/10.1038/s41598-017-05952-3}},
doi = {{10.1038/s41598-017-05952-3}},
volume = {{7}},
year = {{2017}},
}