Modulation of intracellular Cl − homeostasis by lectin-stimulation in Jurkat T lymphocytes

Abstract

We investigated changes in intracellular Cl − concentration ([Cl −] i) during lectin-induced activation and proliferation in human Jurkat T lymphocytes. [Cl −] i was measured using Cl − fluorescence dye ( N-(6-methoyquinolyl) acetoxy-acetyl-ester, MQAE) methods. Lectins, phytohemagglutinin and concanavalin A, dose-dependently increased [Cl −] i and triggered intracellular Cl − oscillation in human Jurkat T lymphocytes. However, some mitochondria metabolism inhibitors, such as m-chlorocarbonylcyanide phenylhydrazone (CCP) and 2,4-dinitrophenol, increased [Cl −] i without triggering any Cl − oscillation. Furthermore, both lectins and metabolism inhibitors-induced elevation in [Cl −] i were blocked by removal of extracellular Cl − from perfusion solution or by application of anthracene-9-carboxylate, a blocker of Cl − channels. Since an extracellular Cl −-free condition and application of 9-AC also inhibited PHA-induced proliferation, we suggested that elevation of [Cl −] i via activation of Cl − channels and increase in incidence of Cl − oscillation would play an important role in modulation of Jurkat T cell activation and proliferation.