Platelets as central mediators of systemic inflammatory responses.
Tammy L Smith1, Andrew S Weyrich
1Program in Molecular Medicine, University of Utah, Salt Lake City, Utah 84112, USA.
Thrombosis Research
|November 16, 2010
Summary
Platelets, beyond clotting, play crucial roles in systemic inflammation and host defense against infection. This review explores novel platelet functions in inflammation and immunity.
Area of Science:
- Immunology
- Hematology
- Pathology
Background:
- Systemic inflammatory responses are linked to significant morbidity and mortality.
- Platelets are traditionally known for hemostasis and thrombosis.
- Emerging evidence highlights platelets' involvement in inflammation beyond traditional roles.
Purpose of the Study:
- To review novel functions of platelets in systemic inflammation.
- To explore the role of platelets in the host response to infection.
Main Methods:
- Literature review of recent studies on platelet function in inflammation and infection.
- Synthesis of evidence on non-traditional platelet activities.
Main Results:
- Platelets contribute to systemic inflammation through adherence, aggregation, and mediator secretion.
- Platelets exhibit non-traditional functions relevant to host defense.
- These novel functions are critical in the response to infectious agents.
Conclusions:
- Platelets are key players in systemic inflammation and immunity.
- Understanding non-traditional platelet functions is vital for managing inflammatory diseases and infections.
Related Concept Videos
01:18Structure and Function of Platelets
The cell fragments known as platelets are disc-shaped, with an average diameter of about 3 μm and a thickness of roughly 1 μm. They play a crucial role in the body's vascular clotting system, which also involves plasma proteins, blood cells, and blood vessel tissues.
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000 platelets, with...
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000 platelets, with...
01:22Formation of the Platelet Plug
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
01:25Acute Inflammation III: Local and Systemic Effects
Acute inflammation produces a coordinated set of local and systemic changes that limit injury, eliminate pathogens, and initiate repair. These responses arise within minutes of infection, trauma, or chemical insult and are driven by vascular alterations and leukocyte-derived mediators. When the stimulus resolves, the reaction typically abates within days.Local EffectsAt the site of injury, arteriolar vasodilation increases blood flow, resulting in redness and warmth. Simultaneously, increased...
01:38Inflammation
Overview
01:05Introduction to Hemostasis
Hemostasis is a complex physiological process that prevents excessive bleeding when a blood vessel is injured. It's crucial for maintaining the integrity of the circulatory system, as it ensures that our blood remains fluid while still within the vascular network and yet clots to prevent blood loss upon vessel injury.
The three phases of hemostasis involve many clotting factors present in plasma and several substances released by platelets and injured tissue cells. It is a fast, localized, and...
The three phases of hemostasis involve many clotting factors present in plasma and several substances released by platelets and injured tissue cells. It is a fast, localized, and...
01:28Inflammatory Response
An inflammatory response is a localized, nonspecific immune reaction that occurs when a tissue is injured. It is characterized by redness, swelling, heat, and pain, which are commonly called the cardinal signs and symptoms of inflammation. Inflammation can sometimes result in a loss of function.
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...