Emerging evidence for platelets as immune and inflammatory effector cells
Matthew T Rondina1, Olivier Garraud2
1Division of General Internal Medicine, University of Utah , Salt Lake City, UT , USA ; Program in Molecular Medicine, University of Utah School of Medicine , Salt Lake City, UT , USA ; Department of Internal Medicine, George E. Wahlen Department of Veterans Affairs Medical Center , Salt Lake City, UT , USA.
Frontiers in Immunology
|January 8, 2015
Summary
Platelets, traditionally known for blood clotting, are now recognized for crucial immune functions. This review explores their roles in host defense against pathogens and infectious diseases.
Area of Science:
- Immunology
- Hematology
- Pathology
Background:
- Platelets were historically viewed primarily for hemostasis.
- Emerging research reveals multifaceted immune roles for platelets.
- These roles bridge thrombotic and inflammatory processes.
Purpose of the Study:
- To review the emerging immune functions of platelets.
- To highlight platelet involvement in host defense against pathogens.
- To discuss implications in clinical infectious syndromes.
Main Methods:
- Literature review of recent studies on platelet immunology.
- Analysis of platelet interactions with immune cells and pathogens.
- Synthesis of findings on platelet-mediated inflammatory responses.
Main Results:
- Platelets secrete immune mediators.
- Platelets interact with endothelial cells, monocytes, and neutrophils.
- Platelets exhibit toll-like receptor (TLR) mediated responses.
- Platelets induce neutrophil extracellular trap (NET) formation.
Conclusions:
- Platelets play dynamic, previously unrecognized roles in immunity.
- These functions are critical for host defense against infection.
- Understanding platelet immunity is vital for managing infectious diseases.
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