Opposing Effects of C-Reactive Protein Isoforms on Shear-Induced Neutrophil-Platelet Adhesion and Neutrophil Aggregation in Whole Blood
Autor: | Tarek Khreiss, János G. Filep, Levente Jozsef, Lawrence A. Potempa |
---|---|
Rok vydání: | 2004 |
Předmět: |
Blood Platelets
Neutrophils Inflammation CD18 GPI-Linked Proteins Flow cytometry Antigens CD Physiology (medical) Cell Adhesion medicine Humans Protein Isoforms Platelet Neutrophil aggregation Cell Aggregation Whole blood Blood Cells medicine.diagnostic_test biology Cell adhesion molecule business.industry Receptors IgG C-reactive protein Platelet Activation Cell biology Kinetics P-Selectin C-Reactive Protein CD18 Antigens Immunology Selectins biology.protein Stress Mechanical medicine.symptom Cardiology and Cardiovascular Medicine business |
Zdroj: | Circulation. 110:2713-2720 |
ISSN: | 1524-4539 0009-7322 |
DOI: | 10.1161/01.cir.0000146846.00816.dd |
Popis: | Background—Plasma C-reactive protein (CRP) level is a powerful predictor of cardiovascular events. However, it is not known whether CRP could affect neutrophil-platelet adhesion and neutrophil aggregation, key events in acute coronary syndromes. Emerging in vitro evidence suggests that some bioactivities of CRP are expressed on loss of the pentameric symmetry, resulting in formation of modified or monomeric CRP (mCRP).Methods and Results—We studied the impact of human native CRP and bioengineered mCRP that cannot rearrange into the pentameric structure on the kinetics of neutrophil-platelet adhesion and neutrophil aggregation in whole blood subjected to shear (≈100 s−1) using real-time flow cytometry. Shear resulted in upregulation of platelet P-selectin expression, leading to platelet capture of neutrophils and subsequent neutrophil aggregation, which was dependent on P-selectin, L-selectin, and CD18. Native CRP at clinically relevant concentrations markedly attenuated these changes. The residual amount of neutrophil adhesion was blocked with anti-CD18 or anti-CD11b antibody. By contrast, mCRP concentration-dependently enhanced shear-induced platelet P-selectin expression and increased the rate and extent of formation of both neutrophil-platelet and neutrophil-neutrophil aggregates. Complete abrogation of platelet-neutrophil adhesion and neutrophil aggregation required both anti-P-selectin and anti-CD18 antibodies but not anti-L-selectin antibody. The CRP action was markedly inhibited by an anti-CD32 antibody, whereas the mCRP effects were significantly attenuated by an anti-CD16 antibody.Conclusions—These results indicate that native CRP inhibits platelet activation and prevents platelet capture of neutrophils, whereas mCRP displays potent prothrombotic activities under low levels of shear. Thus, mCRP rather than native CRP may precipitate acute coronary syndromes. |
Databáze: | OpenAIRE |
Externí odkaz: |