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Immune-Mediated Platelet Activation in COVID-19 and Vaccine-Induced Immune Thrombotic Thrombocytopenia

Günalp Uzun1, Lisann Pelzl2, Anurag Singh2

  • 1Center for Clinical Transfusion Medicine, University Hospital of Tuebingen, Tuebingen, Germany.

Frontiers in Immunology
|March 11, 2022
PubMed

Insights

Platelet abnormalities in COVID-19 correlate with disease severity. Immune-mediated platelet activation contributes to thrombosis in both COVID-19 and vaccine-induced immune thrombotic thrombocytopenia, highlighting therapeutic targets.

Area of Science:

  • Hematology and Immunology
  • Infectious Diseases
  • Vaccinology

Background:

  • Platelet abnormalities, both qualitative and quantitative, are prevalent in COVID-19 patients.
  • Activated platelets are implicated in the prothrombotic state observed in COVID-19.
  • Immune-mediated platelet activation has been documented in critically ill COVID-19 patients.

Purpose of the Study:

  • To review the role of immune-mediated platelet activation in thrombotic complications.
  • To explore platelet activation in both COVID-19 infection and vaccine-induced immune thrombotic thrombocytopenia (VITT).
  • To underscore the therapeutic implications of understanding platelet activation mechanisms.

Main Methods:

  • Literature review focusing on immune-mediated platelet activation.
  • Analysis of studies investigating platelet function in COVID-19.
  • Examination of research on VITT pathogenesis, including Fc gamma RIIA involvement.

Main Results:

  • Platelet abnormalities in COVID-19 correlate with clinical severity and mortality.
  • Immune complexes can activate platelets via Fc gamma RIIA, leading to consumption and thrombosis in VITT.
  • Shared mechanisms of immune-mediated platelet activation may exist between COVID-19 and VITT.

Conclusions:

  • Immune-mediated platelet activation is a critical factor in thrombotic complications of COVID-19.
  • Understanding platelet activation in VITT is crucial, as immune complexes drive thrombosis.
  • Further research into these pathways could yield novel therapeutic strategies for thrombotic disorders.

Keywords:
COVID-19coagulationplatelet activationprocoagulant plateletsthrombosis

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