P2Y12 Receptor Modulates Sepsis-Induced Inflammation

Area of Science:

• Immunology
• Hematology
• Pharmacology

Background:

• Platelets are crucial in hemostasis and immune responses, interacting with immune cells via secreted factors and direct contact.
• The P2Y12 receptor is a key mediator of adenosine diphosphate (ADP)-induced platelet aggregation and secretion.

Purpose of the Study:

• To investigate the role of the P2Y12 receptor in neutrophil migration and lung inflammation during sepsis.
• To evaluate the therapeutic potential of P2Y12 antagonists in mitigating sepsis-induced acute lung injury.

Main Methods:

• Utilized a mouse model of intra-abdominal sepsis and acute lung injury.
• Compared P2Y12 null mice with wild-type littermates.
• Administered the P2Y12 antagonist clopidogrel to wild-type mice and P2Y12 null mice to assess P2Y12-dependent and -independent effects.

Main Results:

• P2Y12 antagonism with clopidogrel reduced circulating white blood cells, platelet activation, and platelet-leukocyte interactions.
• Clopidogrel treatment and P2Y12 deficiency diminished lung injury and platelet sequestration in septic mice.
• Septic P2Y12 null mice exhibited reduced platelet activation and platelet-leukocyte aggregates, showing refractoriness to lung injury compared to wild-type mice.
• Clopidogrel treatment in P2Y12 null mice reduced circulating neutrophils, suggesting pleiotropic effects.

Conclusions:

• P2Y12 null mice are protected from sepsis-induced lung injury, highlighting the critical role of activated platelets and the P2Y12 receptor in sepsis.
• The P2Y12 receptor is essential for sepsis-induced lung inflammation and injury.