Glioma-associated microglia and macrophages/monocytes display distinct electrophysiological properties and do not communicate via gap junctions

Item Type:	Article
Title:	Glioma-associated microglia and macrophages/monocytes display distinct electrophysiological properties and do not communicate via gap junctions
Creators Name:	Richter, N. and Wendt, S. and Georgieva, P.B. and Hambardzumyan, D. and Nolte, C. and Kettenmann, H.
Abstract:	Both brain-resident microglia and peripheral macrophages/monocytes infiltrate into glioma and promote glioma growth. In the present study we analyzed coupling and membrane currents in glioma-associated microglia and macrophages/monocytes and compared this to control and stab wound-associated microglia. Using the Cx3cr1(GFP/wt)Ccr2(RFP/wt) knock-in mouse line, we distinguished membrane currents of glioma-associated microglia and macrophages/monocytes in acute brain slices prepared 14-16 days after inoculation of GL261 glioma cells. The current profile of microglia showed inward rectifying currents reminiscent of an intermediate activation state when compared to other disease models or cell culture. Macrophages/monocytes showed a higher specific outward conductance and a significantly lower capacitance indicative of a smaller membrane area than microglia. As controls, we also recorded currents from control microglia and stab wound-associated microglia. Since there are reports of microglial coupling in vitro, we injected biocytin into these cells and analyzed for cell coupling after fixing the slices and processed for biocytin labeling with Cy3-conjugated-Streptavidin. Neither control microglia nor glioma-associated microglia and macrophages/monocytes nor stab wound-associated microglia showed any sign of coupling. Moreover, performing qRT-PCR revealed that no connexin43 was detectable on isolated and sorted glioma-associated microglia and macrophages/monocytes, indicating that these cells are not part of a coupled network.
Keywords:	Glioma-Associated Microglia, Glioma-Associated Macrophages/Monocytes, Glioma, Gap Junctions, Electrophysiology, Animals, Mice
Source:	Neuroscience Letters
ISSN:	0304-3940
Publisher:	Elsevier
Volume:	583
Page Range:	130-135
Date:	7 November 2014
Additional Information:	Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Official Publication:	https://doi.org/10.1016/j.neulet.2014.09.035
External Fulltext:	View full text on PubMed Central
PubMed:	View item in PubMed

Repository Staff Only: item control page