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Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells
Published on: October 27, 2009
Lactotransferrin binding to its platelet receptor inhibits platelet aggregation
B Leveugle1, J Mazurier, D Legrand
1Laboratoire de Chimie Biologique, Centre National de la Recherche Scientifique no 111, Université des Sciences et Technologies de Lille France.
European Journal of Biochemistry
|May 1, 1993
Summary
A novel fluorescent probe reveals lactotransferrin binding to human platelets, inhibiting aggregation. This interaction involves a specific platelet receptor, distinct from glycoprotein IIb-IIIa, and is mediated by lactotransferrin
Area of Science:
- Biochemistry
- Immunology
- Hematology
Background:
- Lactotransferrin (LTF) plays a role in immune responses and has been detected in human plasma.
- Platelet aggregation is a critical process in hemostasis and thrombosis.
- The interaction between LTF and platelets, and its functional consequences, remain incompletely understood.
Purpose of the Study:
- To develop a method for studying LTF binding to non-activated human platelets.
- To characterize the LTF receptor on platelets.
- To investigate the effect of LTF on platelet aggregation and identify the responsible domains.
Main Methods:
- Synthesis of a fluorescent LTF probe via modification of glycan moieties.
- Flow cytometry analysis of LTF-platelet binding.
- Purification and characterization of the putative LTF platelet receptor.
- Assessment of LTF and its fragments' ability to inhibit ADP-induced platelet aggregation.
Main Results:
- A functional fluorescent LTF probe was successfully created, enabling detection of LTF binding to non-activated platelets.
- A putative LTF receptor on platelets was identified, sharing properties with a receptor found on lymphocytes.
- LTF inhibits ADP-induced platelet aggregation at nanomolar concentrations, with activity localized to specific peptide regions.
Conclusions:
- LTF binds to a specific receptor on non-activated human platelets, distinct from glycoprotein IIb-IIIa.
- This binding inhibits platelet aggregation, suggesting a role for LTF in regulating platelet function.
- The N-terminal fragment and specific peptide sequences of LTF are responsible for its anti-aggregatory activity.
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