Go to page

Bibliographic Metadata

Platelet-borne complement proteins and their role in platelet-bacteria interactions
AuthorMannhalter, Christine ; Fischer, M. B. ; Bucsaiova, M. ; Arbesu, I.
Published in
Journal of Thrombosis and Haemostasis, Hoboken, 2016, Vol. 14, Issue 11, page 2241-2252
PublishedHoboken : Journal of Thrombosis and Haemostasis, 2016
Document typeJournal Article
Keywords (EN)complement / gram-negative bacteria / infection / megakaryocytes / platelets / hemolytic-uremic syndrome / neutrophil extracellular traps / staphylococcus-aureus / escherichia-coli / shiga toxin / o-antigen / activation / mechanisms / receptor / blood
Project-/ReportnumberW 1205-B09
URNurn:nbn:at:at-ubmuw:3-1821 Persistent Identifier (URN)
 The work is publicly available
Platelet-borne complement proteins and their role in platelet-bacteria interactions [0.67 mb]
Abstract (English)

Background: The role of platelets in immune defense is increasingly being recognized. Platelets bind complement proteins from plasma, initiate complement activation, and interact with bacteria. However, the contribution of platelets to complement-mediated defense against bacterial infections is not known in detail. Objectives: To assess platelet interactions with Escherichia coli strains, and evaluate the contributions of platelet complement proteins to host defense. Methods: We studied the cell-cell interactions of a pathogenic and a non-pathogenic E. coli strain with platelet concentrates, washed platelets and manually isolated platelets by flow cytometry and ELISA. The presence of complement proteins and complement RNA in megakaryocytes and platelets was analyzed by PCR, RT-PCR, confocal microscopy, and western blotting. Results: Incubation with E. coli leads to platelet activation, as indicated by the expression of CD62P and CD63 on the platelet surface. RNA and protein analyses show that megakaryocytes and platelets contain complement C3, and that platelet C3 migrates differently on polyacrylamide gels than plasmatic C3. Activation of platelets by bacteria leads to translocation of C3 to the cell surface. This translocation is not induced by thrombin receptor activating peptide or lipopolysaccharide. Interaction of platelets with E. coli occurs even in the absence of plasma proteins, and is independent of platelet toll-like receptor 4 and alpha(2b)beta(3) (glycoprotein IIbIIIa). Conclusion: Platelets contain a specific form of C3. Importantly, they can modulate immune defense against bacteria by enhancing plasmatic complement activation.

The PDF-Document has been downloaded 3 times.
CC-BY-License (4.0)Creative Commons Attribution 4.0 International License