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Comprehensive Analysis of Procoagulant Platelets Exhibiting Features of Necrosis, Apoptosis and Platelet Activation
Published on: May 23, 2025
Complement activation in thrombotic thrombocytopenic purpura.
1Department of Hematology and Stem Cell Transplantation, St István and St László Hospital of Budapest, Budapest, Hungary.
Journal of Thrombosis and Haemostasis : JTH
|March 1, 2012
Summary
Complement activation is present in thrombotic thrombocytopenic purpura (TTP) patients, indicated by elevated C3a and sC5b9 levels during acute episodes. This suggests a potential role for complement in TTP pathogenesis.
Area of Science:
- Hematology
- Immunology
- Complement System
Background:
- Thrombotic microangiopathy involves ultra-large von Willebrand factor and its cleaving protease deficiency.
- Complement activation is linked to atypical hemolytic uremic syndrome, but its role in thrombotic thrombocytopenic purpura (TTP) is unclear.
Purpose of the Study:
- To investigate the presence and characteristics of complement activation in patients with TTP.
Main Methods:
- Assessed complement parameters (C3, Factors H, I, B, alternative pathway activity) and activation fragments/complexes (C3a, C1rs-INH, C3bBbP, sC5b9) in 23 TTP patients and 17 controls.
- Measured ADAMTS13 activity and anti-ADAMTS13 antibodies.
Main Results:
- Elevated C3a and sC5b9 levels were observed in TTP patients during acute episodes compared to controls.
- Complement consumption (decreased C3) occurred in 15% of acute TTP patients.
- Complement activation markers decreased after plasma exchange; sustained antibodies correlated with increased complement activation.
Conclusions:
- This study documents the presence of complement activation in TTP.
- Further research is required to elucidate the pathogenetic role of complement activation in TTP.
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