Presentation

Biology and pharmacology of blood platelets: Haemostasis, thrombosis, transfusion

Blood platelets play a major physiological role in ensuring the arrest of bleeding (haemostasis) and, in pathology, in the occurrence and extension of arterial thrombosis (myocardial infarction, stroke and peripheral arterial disease). Abnormalities in platelet production and function are the cause of serious haemorrhagic diseases. In addition to their involvement in haemostasis and thrombosis, platelets are involved in non-haemostatic processes such as inflammation, angiogenesis, immunity, embryonic development and metastatic dissemination.

For more than 30 years, the Inserm 1255 unit has been studying the role of blood platelets in its laboratory on aspects related to biology, genetics, pharmacology, clinical and transfusion. Our approaches are both fundamental and translational. The group is structured around two interconnected teams that are interested, respectively, in the role of platelets in haemostasis and thrombosis and in transfusion, and in the mechanisms and defects of platelet production.

Among the unit’s main contributions we can mention:

• The identification and characterization of purinergic P2 receptors for ADP (P2Y1 and P2Y12) and ATP (P2X1), each of them having a specific role in platelet activation.
• Study of the role of platelet adhesion receptors including the GPIb-V-IX complex, GPVI and integrins of the β1 and β3 families. Pharmacological agents have been developed collaboratively and some are currently being evaluated in a clinical phase.
• Molecular characterization of patients with platelet hereditary defects, including those with the Bernard-Soulier syndrome or with defects in intraplatelet granules, tubulin and the P2Y12 receptor.
• Advances were made in the physiology and pathology of megakaryopoiesis, , on the role of the cellular microenvironment and its biomechanical constraints, on the mechanisms of passage through the wall of sinusoid vessels and of microtubule assembly.

In blood transfusion, implementation and characterization of pathogen inactivation processes in labile blood products, plasma, platelet concentrates and red cell concentrates.