Related Experiment Video
Updated: Jun 12, 2026
11:42
Live-cell Imaging of Platelet Degranulation and Secretion Under Flow
Published on: July 10, 2017
Platelet RIP2 Limits Dense Granule Release and Thrombosis via DOCK8-Cdc42
Jianjun Zhang1,2, Zhiling Zhang1,3, Guanxing Pan1
1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences (J.Z., Z.Z., G.P., L.C., Y.Z., S.Z., Z.D.), Fudan University, Shanghai, China.
Arteriosclerosis, Thrombosis, and Vascular Biology
|June 11, 2026
Summary
Receptor-interacting protein kinase 2 (RIP2) restrains platelet activation and thrombosis, mitigating myocardial infarction. Targeting the RIP2 pathway may offer a therapeutic strategy against atherothrombotic diseases.
Area of Science:
- Immunology
- Cardiovascular Biology
- Platelet Biology
Background:
- Receptor-interacting protein kinase 2 (RIP2) is crucial for inflammation and innate immunity.
- Platelets express RIP2, but its role in platelet activation, thrombosis, and myocardial infarction remains unclear.
- The potential involvement of the pattern recognition receptor (PRR) pathway in these platelet functions is unknown.
Purpose of the Study:
- To investigate the role of RIP2 in platelet activation, thrombosis, and myocardial infarction.
- To determine if RIP2's effects are mediated through the PRR pathway.
- To elucidate the molecular mechanism by which RIP2 influences platelet function.
Main Methods:
- Assessed platelet aggregation, granule secretion, spreading, and clot retraction in vitro.
- Utilized ex vivo microfluidic whole blood perfusion and in vivo thrombosis/myocardial infarction models.
- Performed immunoprecipitation, LC-MS/MS, and Western blotting to analyze RIP2 function and expression.
Main Results:
- RIP2 deficiency enhances platelet dense granule secretion and aggregation.
- RIP2 inhibition potentiates human platelet dense granule secretion.
- RIP2 deficiency worsens myocardial infarction and cardiac function in mice, with lower RIP2 in patients with coronary artery disease.
Conclusions:
- RIP2 restrains platelet activation and thrombosis, mitigating myocardial infarction.
- A novel PRR-independent pathway (p-RIP2-DOCK8-Cdc42) suppresses dense granule release.
- Targeting the platelet RIP2 pathway offers a potential therapeutic strategy for atherothrombotic diseases.
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