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10:10
Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells
Published on: October 27, 2009
A functional integrin ligand on the surface of platelets: intercellular adhesion molecule-2
T G Diacovo1, A R deFougerolles, D F Bainton
1Harvard Medical School, Division of Newborn Medicine, Boston, Massachusetts 02115.
The Journal of Clinical Investigation
|September 1, 1994
Summary
Platelets express intercellular adhesion molecule-2 (ICAM-2), a molecule crucial for leukocyte interactions. This finding suggests ICAM-2 plays a key role in inflammation and thrombosis.
Area of Science:
- Immunology
- Hematology
- Cell Biology
Background:
- Platelets are known to express P-selectin and release chemoattractants.
- However, their role in stabilizing leukocyte interactions via integrin ligands was unclear.
Purpose of the Study:
- To investigate the expression of beta 2-integrin ligands on platelets.
- To determine the role of ICAM-2 in leukocyte-platelet interactions.
Main Methods:
- Immunohistochemistry on bone marrow aspirates and platelet samples.
- Immunogold labeling of platelet surface and internal structures.
- Platelet adhesion assays using purified leukocyte function-associated antigen-1 (LFA-1) and activated T lymphocytes.
Main Results:
- Intercellular adhesion molecule-2 (ICAM-2) is expressed on resting and activated platelets, but not ICAM-1 or ICAM-3.
- ICAM-2 is present on the plasma membrane and surface-connected canalicular system.
- Platelets bind to LFA-1 via ICAM-2, and this binding is enhanced by T lymphocyte activation.
Conclusions:
- ICAM-2 is the sole beta 2-integrin ligand identified on platelets.
- ICAM-2 likely mediates critical leukocyte-platelet interactions in inflammatory and thrombotic conditions.
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