Related Experiment Video
Updated: Feb 16, 2026

Isolation of Human Lymphatic Endothelial Cells by Multi-parameter Fluorescence-activated Cell Sorting
Published on: May 1, 2015
Contribution of activated beta3 integrin in the PDI release from endothelial cells
Halszka Ponamarczuk1, Marcin Popielarski1, Marta Stasiak1
1Department of Cytobiology and Proteomics, Medical University of Lodz, Poland.
Abstract:
Protein disulfide isomerase (PDI) is an abundant reticulum endoplasmic protein but also acts as an important functional regulator of some extracellular surface proteins. Recent studies suggest that PDI plays a role in integrin activation and thrombus formation. The aim of this study was to examine whether activation of integrin is the first stage leading to release of PDI from the subcellular compartments of endothelial cells to extracellular space. Our results show that endothelial cells which adhere to fibronectin or fibrinogen release significantly more PDI than those which adhere to poly-L-lysine. Cells treated with RGD peptide, Src and FAK kinase inhibitors and anti alphaVbeta3 antibody display lower PDI secretion. The destruction of the actin cytoskeleton of endothelial cells by cytochalasin D inhibits PDI release. When the endothelial cells adhere to fibrinogen or fibronectin, PDI and alphaVbeta3 gain free thiol groups. Our data suggest that upon activation of integrins, PDI is released from endothelial cells and forms a disulfide bond complex with alphaVbeta3 integrin.
Related Concept Videos
Activation of Integrins
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding...
Integrins
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
Binet's Contribution to Measures of Intelligence
Modified-Release Drug Delivery Systems: Stimuli-Activated
Wechsler's Contribution to Measures of Intelligence
Energy-releasing Steps of Glycolysis
The first energy-releasing step—the 6th step of glycolysis...

