Potassium Channels Kv1.3 and Kir2.1 But Not Kv1.5 Contribute to BV2 Cell Line and Primary Microglial Migration.

Ruxandra Anton,Christophe Gattlen,Aurel Popa-Wagner,Marc-Rene Suter,Alexandru-Florian Deftu,Mihail Ghenghea,Petre Alexandru Cojocaru,Violeta Ristoiu,Bogdan Catalin

doi:10.3390/ijms22042081

Abstract

(1) Background: As membrane channels contribute to different cell functions, understanding the underlying mechanisms becomes extremely important. A large number of neuronal channels have been investigated, however, less studied are the channels expressed in the glia population, particularly in microglia. In the present study, we focused on the function of the Kv1.3, Kv1.5 and Kir2.1 potassium channels expressed in both BV2 cells and primary microglia cultures, which may impact the cellular migration process. (2) Methods: Using an immunocytochemical approach, we were able to show the presence of the investigated channels in BV2 microglial cells, record their currents using a patch clamp and their role in cell migration using the scratch assay. The migration of the primary microglial cells in culture was assessed using cell culture inserts. (3) Results: By blocking each potassium channel, we showed that Kv1.3 and Kir2.1 but not Kv1.5 are essential for BV2 cell migration. Further, primary microglial cultures were obtained from a line of transgenic CX3CR1-eGFP mice that express fluorescent labeled microglia. The mice were subjected to a spared nerve injury model of pain and we found that microglia motility in an 8 µm insert was reduced 2 days after spared nerve injury (SNI) compared with sham conditions. Additional investigations showed a further impact on cell motility by specifically blocking Kv1.3 and Kir2.1 but not Kv1.5; (4) Conclusions: Our study highlights the importance of the Kv1.3 and Kir2.1 but not Kv1.5 potassium channels on microglia migration both in BV2 and primary cell cultures.

Highlights

IntroductionAs the resident immune population of the central nervous system (CNS), microglia are constantly surveying their environment, permanently changing each individual arborization by generating new processes and retracting existing ones [1,2]
We were able to (i) detect the expression of these potassium using immunocytochemistry, we were able to (i) detect the expression of these potassium channels in cultured BV2 cells, (ii) show that Kv1.3 and Kir2.1 but not Kv1.5 are essential channels in cultured BV2 cells, (ii) show that Kv1.3 and Kir2.1 but not Kv1.5 are essential for BV2 cell migration by blocking each potassium channel, (iii) record the for BV2 cell migration by blocking each potassium channel, (iii) record the electrophysiological properties of these channels in BV2 cells and (iv) to demonstrate their electrophysiological properties of these channels in BV2 cells and (iv) to demonstrate their impact on microglia motility in primary cultures derived from a mouse model of neuropathic pain
This study indicates the presence of the Kv1.3, Kv1.5 and Kir2.1 potassium channels at the plasma membrane of the BV2 microglial cell line using immunocytochemistry and electrophysiological recordings

Summary

Introduction

As the resident immune population of the CNS, microglia are constantly surveying their environment, permanently changing each individual arborization by generating new processes and retracting existing ones [1,2]. This implies that microglia morphology can vary from region to region, with spinal microglia having a distinct morphology when compared to the microglia in the cortex [3]. Body migration is almost synonymous with microglia activation that will, in turn, initiate a long-lasting change in its physiology [5,6,7]

Methods

Discussion

Conclusion