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Updated: Jul 20, 2026

Whole-Cell Recording of Calcium Release-Activated Calcium (CRAC) Currents in Human T Lymphocytes
15:29

Whole-Cell Recording of Calcium Release-Activated Calcium (CRAC) Currents in Human T Lymphocytes

Published on: December 21, 2010

A voltage-gated calcium channel is linked to the antigen receptor in Jurkat T lymphocytes

J J Densmore1, G Szabo, L S Gray

  • 1Department of Pathology, University of Virginia Health Sciences Center, Charlottesville 22908.

FEBS Letters
|November 9, 1992
PubMed

Insights

T lymphocyte activation increases intracellular calcium via extracellular influx. Research suggests a voltage-regulated calcium channel mediates this antigen receptor-induced calcium entry in T cells.

Area of Science:

  • Immunology
  • Cell Biology
  • Neuroscience

Background:

  • T lymphocyte activation is crucial for immune responses.
  • This activation involves a significant increase in intracellular calcium (Ca2+).
  • Extracellular Ca2+ influx is a primary source for this calcium increase.

Purpose of the Study:

  • To investigate the mechanism of Ca2+ influx during T lymphocyte activation.
  • To identify the type of channel mediating antigen receptor-induced Ca2+ entry.
  • To determine if this channel is voltage-regulated.

Main Methods:

  • Utilized the patch clamp technique on Jurkat T lymphocytes.
  • Applied depolarization from different holding potentials (-90 mV and -60 mV).
  • Tested the current's properties using various ions (Ba2+, Ni2+) and tetrodotoxin.

Main Results:

  • Observed an inward whole-cell current upon depolarization from -90 mV, but not -60 mV.
  • The current was insensitive to tetrodotoxin.
  • The current was carried by Ba2+ and blocked by Ni2+, indicating Ca2+ channel activity.
  • Antigen receptor occupancy enhanced the current's magnitude.

Conclusions:

  • T lymphocyte activation involves a voltage-regulated Ca2+ influx.
  • Antigen receptor signaling modulates this voltage-gated Ca2+ channel.
  • These findings suggest a novel pathway for calcium regulation in T cells.

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