Related Experiment Video

Updated: Jun 16, 2026

Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement
10:45

Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement

Published on: July 26, 2017

Pivotal Advance: Nonfunctional lung effectors exhibit decreased calcium mobilization associated with reduced

Subhashini Arimilli1, Sharad K Sharma, Rama Yammani

  • 11. Room 5140 Gray Building, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA.

Journal of Leukocyte Biology
|January 28, 2010
PubMed

Insights

Functional inactivation of lung effector CD8(+) T cells during viral infections is linked to reduced calcium signaling. Restoring extracellular calcium levels and ORAI1 expression can reverse this functional defect.

Area of Science:

  • Immunology
  • Virology
  • Cellular Biology

Background:

  • CD8(+) T cells are crucial for clearing respiratory pathogens.
  • Functional inactivation of lung effector T cells occurs during viral infections.
  • The molecular mechanisms underlying this T cell dysfunction remain unclear.

Purpose of the Study:

  • To investigate the molecular basis for functional inactivation of lung effector T cells during viral infections.
  • To identify the specific defects leading to T cell dysfunction in the context of respiratory viral infections.

Main Methods:

  • Utilized a mouse model of respiratory infection with the paramyxovirus SV5.
  • Assessed the function of CD8(+) T cells, including calcium signaling (SOCE) and NFAT1 activation.
  • Quantified ORAI1 expression in T cells.
  • Investigated the effect of extracellular calcium levels on T cell function.

Main Results:

  • Nonfunctional CD8(+) T cells exhibited decreased store-operated calcium entry (SOCE).
  • Reduced SOCE correlated with diminished NFAT1 activation.
  • T cell function could be restored by increasing extracellular calcium.
  • Decreased ORAI1 expression was observed in nonfunctional T cells, impacting calcium mobilization.

Conclusions:

  • Reduced ORAI1 expression leads to impaired calcium mobilization and SOCE in effector T cells during viral infections.
  • This calcium signaling defect results in functional inactivation of CD8(+) T cells.
  • The findings reveal a novel mechanism of T cell immune evasion by respiratory viruses.

Related Concept Videos

Calmodulin-dependent Signaling01:16

Calmodulin-dependent Signaling

Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Chronic Obstructive Pulmonary Disease-II: Pathophysiology01:20

Chronic Obstructive Pulmonary Disease-II: Pathophysiology

Chronic Obstructive Pulmonary Disease (COPD) pathophysiology is intricate and multifaceted, involving a complex interplay of physiological processes. Understanding these mechanisms is crucial for effectively managing and treating COPD. Here is an in-depth look at the critical elements in the pathophysiology of COPD:
Chronic Inflammation
Atelectasis II: Pathophysiology01:10

Atelectasis II: Pathophysiology

Atelectasis develops when alveoli lose their air and collapse inward. Because lung tissue is naturally elastic, these air sacs shrink rather than remaining open. Collapsed alveoli are no longer ventilated, reducing their role in gas exchange. Blood flow may continue in these regions, creating a ventilation–perfusion mismatch. Clinical findings include decreased breath sounds, dullness to percussion, reduced chest expansion, and decreased tactile fremitus as sound transmission through collapsed...
Feedback Regulation of Calcium Concentration01:27

Feedback Regulation of Calcium Concentration

Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Pulmonary Function Tests01:25

Pulmonary Function Tests

Pulmonary Function Tests (PFTs)
Pulmonary Function Tests are crucial diagnostic tools for assessing respiratory function, particularly in patients with chronic respiratory disorders. They comprehensively evaluate lung volumes, ventilatory function, breathing mechanics, diffusion, and gas exchange. These tests help diagnose pulmonary diseases and play a significant role in monitoring disease progression, evaluating disability, and assessing response to therapy.
PFTs involve using a spirometer, a...
Nitric Oxide Signaling Pathway01:28

Nitric Oxide Signaling Pathway

Nitric oxide (NO), an inorganic gas, acts as a potent second messenger in most animal and plant tissues. NO diffuses out of the cells that produce it and enters the neighboring cells to generate a downstream response. NO synthase (NOS) catalyzes NO production by the deamination of the amino acid arginine. There are three isoforms of NOS. Endothelial cells have endothelial NOS (eNOS), nerve and muscle cells have neuronal NOS (nNOS), and macrophages produce inducible NOS (iNOS) upon exposure to...