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Updated: Jun 24, 2026
11:22
Quantitative In vitro Assay to Measure Neutrophil Adhesion to Activated Primary Human Microvascular Endothelial Cells under Static Conditions
Published on: August 23, 2013
Beta2-integrin-mediated adhesion and intracellular Ca2+ release in human eosinophils
Jennifer L Bankers-Fulbright1, Kathleen R Bartemes, Gail M Kephart
1Department of Biology, Augsburg College, Minneapolis, MN 55454, USA.
The Journal of Membrane Biology
|March 18, 2009
Summary
Human eosinophils adhere to surfaces via a process involving intracellular calcium and cytoskeletal changes. This study introduces a novel impedance method to measure eosinophil adhesion dynamics.
Area of Science:
- Immunology
- Cell Biology
- Biophysics
Background:
- Human eosinophils exhibit spontaneous adhesion to surfaces without external activators.
- Understanding eosinophil adhesion is crucial for studying inflammatory responses.
Purpose of the Study:
- To develop and characterize a novel impedance-based method for measuring eosinophil adhesion.
- To elucidate the molecular mechanisms underlying eosinophil adhesion.
Main Methods:
- Eosinophil adhesion was measured by changes in electrical impedance.
- Intracellular calcium mobilization was blocked using BAPTA-AM.
- Extracellular calcium was chelated using EGTA.
- Beta(2)-integrin and actin reorganization were inhibited using anti-CD18 antibody and jasplakinolide, respectively.
- Phosphatidylinositol 3-kinase and protein kinase C zeta were inhibited using LY294002 and a pseudosubstrate inhibitor.
Main Results:
- A rapid increase in impedance (>1 kOmega within minutes) indicated eosinophil adhesion.
- Intracellular calcium mobilization was essential for adhesion and cell shape changes.
- Extracellular calcium levels did not affect impedance changes.
- Beta(2)-integrin interactions and actin reorganization were critical for adhesion.
- Inhibition of phosphatidylinositol 3-kinase and protein kinase C zeta reduced adhesion and cell spreading.
Conclusions:
- A novel impedance method effectively quantifies eosinophil adhesion.
- Eosinophil adhesion involves a rapid intracellular calcium increase preceding cytoskeletal rearrangements.
- Beta(2)-integrins, actin dynamics, PI3K, and PKCzeta play key roles in eosinophil adhesion.
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