Platelets reprogram monocyte functions by secreting MMP-9 to benefit postoperative outcomes following acute aortic

Wei-Yun Shen1,2, Hui Li1,2, An-Hui Zha1,2

  • 1Department of Anesthesiology, The Second Xiangya Hospital, Central South University, Changsha, China.

Iscience
|May 30, 2023
PubMed

Insights

Platelets, despite being reduced in acute aortic dissection (AAD), become activated and form aggregates with monocytes. These monocyte-platelet aggregates (MPAs) help restore immune function, improving surgical recovery in AAD patients.

Area of Science:

  • Immunology
  • Cardiovascular Surgery
  • Hematology

Background:

  • Monocyte-platelet aggregates (MPAs) are implicated in cardiac disease pathogenesis.
  • Low preoperative platelet counts predict poor postoperative recovery in acute aortic dissection (AAD).
  • The specific roles of platelets and MPAs in AAD remain unclear.

Purpose of the Study:

  • To investigate the function of platelets and MPAs in patients with acute aortic dissection (AAD).
  • To explore the relationship between platelet activation, MPAs, and postoperative recovery in AAD.
  • To elucidate the mechanism by which platelets influence monocyte function in AAD.

Main Methods:

  • Analysis of platelet counts and activation markers in AAD patients.
  • Assessment of monocyte immune status and its correlation with surgical outcomes.
  • Quantification of monocyte-platelet aggregates (MPAs) and their association with recovery.
  • Evaluation of platelet-mediated restoration of monocyte function, including matrix metalloproteinase-9 (MMP-9) secretion.

Main Results:

  • AAD patients exhibited decreased platelet counts but increased platelet activation.
  • Monocytes in AAD patients showed suppressed immune status, linked to poorer surgical outcomes.
  • Elevated levels of MPAs correlated with improved recovery after AAD surgical repair.
  • Platelets, via aggregation and MMP-9 secretion, restored suppressed monocyte functions in AAD patients.

Conclusions:

  • Platelets play a crucial role in immune modulation in AAD, despite reduced overall counts.
  • Monocyte-platelet aggregates (MPAs) are key mediators in AAD, influencing postoperative recovery.
  • Platelet-driven monocyte reprogramming represents a novel mechanism potentially improving outcomes in complex cardiovascular surgery.

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