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Updated: Aug 8, 2026
15:29
Whole-Cell Recording of Calcium Release-Activated Calcium (CRAC) Currents in Human T Lymphocytes
Published on: December 21, 2010
A large, multiple-conductance chloride channel in normal human T lymphocytes
L C Schlichter1, R Grygorczyk, P A Pahapill
1Department of Physiology, University of Toronto, Ontario, Canada.
Pflugers Archiv : European Journal of Physiology
|June 1, 1990
Summary
Researchers identified a large conductance chloride channel in human T lymphocytes, crucial for cell function. This channel exhibits voltage-dependent gating and selective ion permeability, offering new insights into lymphocyte physiology.
Area of Science:
- Ion channel biophysics
- Human lymphocyte physiology
- Cellular transport mechanisms
Background:
- Chloride (Cl) channels are implicated in lymphocyte functions like volume regulation and cytotoxicity.
- Direct characterization of these channels in normal human lymphocytes is limited.
Purpose of the Study:
- To describe a large conductance Cl channel in normal human peripheral T lymphocytes.
- To characterize its biophysical properties, including conductance, voltage dependence, and ion selectivity.
Main Methods:
- Utilized excised, inside-out patch-clamp electrophysiology on normal human peripheral T lymphocytes.
- Analyzed single-channel currents to determine conductance, voltage dependence, and ion selectivity.
Main Results:
- Identified a large conductance Cl channel (approx. 365 pS) in ~50% of T lymphocyte patches.
- The channel displays voltage-dependent gating, with maximal opening probability between -15 mV and +15 mV.
- Demonstrated high selectivity for Cl- over Na+ and K+ (approx. 30:1) and characterized anion selectivity sequence.
Conclusions:
- A novel, large conductance Cl channel exists in human T lymphocytes.
- This channel's properties suggest a significant role in lymphocyte function.
- Further research is warranted to elucidate its specific physiological roles.
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