Genetic analysis of the role of protein kinase Ctheta in platelet function and thrombus formation
| Autor: | Judith M.E.M. Cosemans, Matthew T. Harper, Johan W. M. Heemskerk, Karen Gilio, Alastair W. Poole, Kellie J. Hall |
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| Přispěvatelé: | Harper, Matthew [0000-0002-4740-637X], Apollo - University of Cambridge Repository |
| Rok vydání: | 2020 |
| Předmět: |
Blood Platelets
Platelet Aggregation Integrin Hematology/Coagulation Disorders Cardiovascular Disorders/Coronary Artery Disease lcsh:Medicine Biology Models Biological Cell Biology/Cell Signaling Autoimmune Diseases 03 medical and health sciences Mice 0302 clinical medicine Platelet Adhesiveness Platelet adhesiveness Cell Biology/Cytoskeleton Biochemistry/Cell Signaling and Trafficking Structures Animals Protein Isoforms Platelet Platelet activation lcsh:Science Protein kinase A Protein kinase C Protein Kinase C 030304 developmental biology 0303 health sciences Multidisciplinary Kinase lcsh:R Biochemistry/Chemical Biology of the Cell Thrombosis Platelet Activation Cell biology Isoenzymes Mice Inbred C57BL Cell Biology/Cell Adhesion Gene Expression Regulation Protein Kinase C-theta 030220 oncology & carcinogenesis Immune System biology.protein Physiology/Cell Signaling lcsh:Q Collagen GPVI Research Article Pharmacology/Drug Development |
| Zdroj: | PLoS ONE PLoS ONE, Vol 3, Iss 9, p e3277 (2008) |
| DOI: | 10.17863/cam.52930 |
| Popis: | BACKGROUND: PKCtheta is a novel protein kinase C isozyme, predominately expressed in T cells and platelets. PKCtheta(-/-) T cells exhibit reduced activation and PKCtheta(-/-) mice are resistant to autoimmune disease, making PKCtheta an attractive therapeutic target for immune modulation. Collagen is a major agonist for platelets, operating through an immunoreceptor-like signalling pathway from its receptor GPVI. Although it has recently been shown that PKCtheta positively regulates outside-in signalling through integrin alpha(IIb)beta(3) in platelets, the role of PKCtheta in GPVI-dependent signalling and functional activation of platelets has not been assessed. METHODOLOGY/PRINCIPAL FINDINGS: In the present study we assessed static adhesion, cell spreading, granule secretion, integrin alpha(IIb)beta(3) activation and platelet aggregation in washed mouse platelets lacking PKCtheta. Thrombus formation on a collagen-coated surface was assessed in vitro under flow. PKCtheta(-/-) platelets exhibited reduced static adhesion and filopodia generation on fibrinogen, suggesting that PKCtheta positively regulates outside-in signalling, in agreement with a previous report. In contrast, PKCtheta(-/-) platelets also exhibited markedly enhanced GPVI-dependent alpha-granule secretion, although dense granule secretion was unaffected, suggesting that PKCtheta differentially regulates these two granules. Inside-out regulation of alpha(IIb)beta(3) activation was also enhanced downstream of GPVI stimulation. Although this did not result in increased aggregation, importantly thrombus formation on collagen under high shear (1000 s(-1)) was enhanced. CONCLUSIONS/SIGNIFICANCE: These data suggest that PKCtheta is an important negative regulator of thrombus formation on collagen, potentially mediated by alpha-granule secretion and alpha(IIb)beta(3) activation. PKCtheta therefore may act to restrict thrombus growth, a finding that has important implications for the development and safe clinical use of PKCtheta inhibitors. |
| Databáze: | OpenAIRE |
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