Referenced in: none

Automatically associated channels: Nav1.7

Title: Voltage-gated sodium channel Nav1.7 maintains the membrane potential and regulates the activation and chemokine-induced migration of a monocyte-derived dendritic cell subset.

Authors: Katalin Kis-Toth, Péter Hajdu, Ildiko Bacskai, Orsolya Szilágyi, Ferenc Papp, Attila Szanto, Edit Posta, Peter Gogolak, Gyorgy Panyi, Eva Rajnavölgyi

Journal, date & volume: J. Immunol., 2011 Aug 1 , 187, 1273-80

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/21715690

Abstract
Expression of CD1a protein defines a human dendritic cell (DC) subset with unique functional activities. We aimed to study the expression of the Nav1.7 sodium channel and the functional consequences of its activity in CD1a(-) and CD1a(+) DC. Single-cell electrophysiology (patch-clamp) and quantitative PCR experiments performed on sorted CD1a(-) and CD1a(+) immature DC (IDC) showed that the frequency of cells expressing Na(+) current, current density, and the relative expression of the SCN9A gene encoding Nav1.7 were significantly higher in CD1a(+) cells than in their CD1a(-) counterparts. The activity of Nav1.7 results in a depolarized resting membrane potential (-8.7 ± 1.5 mV) in CD1a(+) IDC as compared with CD1a(-) cells lacking Nav1.7 (-47 ± 6.2 mV). Stimulation of DC by inflammatory signals or by increased intracellular Ca(2+) levels resulted in reduced Nav1.7 expression. Silencing of the SCN9A gene shifted the membrane potential to a hyperpolarizing direction in CD1a(+) IDC, resulting in decreased cell migration, whereas pharmacological inhibition of Nav1.7 by tetrodotoxin sensitized the cells for activation signals. Fine-tuning of IDC functions by a voltage-gated sodium channel emerges as a new regulatory mechanism modulating the migration and cytokine responses of these DC subsets.