Platelets and the complement cascade in atherosclerosis

Johannes Patzelt1, Admar Verschoor2, Harald F Langer3

  • 1University Clinic for Cardiovascular Medicine, University of Tuebingen Tuebingen, Germany.

Insights

Platelets and the complement system interact in atherosclerosis, a major cause of death. Understanding this cross-talk offers new avenues for treating cardiovascular disease and its complications.

Area of Science:

  • Cardiovascular Science
  • Immunology
  • Hematology

Background:

  • Atherosclerosis is a leading cause of mortality, driven by inflammatory processes.
  • Platelets play a critical role in both the development and acute complications of atherosclerosis.
  • The complement system, a key part of innate immunity, is increasingly implicated in atherosclerosis.

Purpose of the Study:

  • To review the intersection between platelets and the complement system in atherosclerosis.
  • To discuss the roles of platelets and complement in disease onset and progression.
  • To explore emerging literature on platelet-complement cross-talk and its impact on atherosclerosis.

Main Methods:

  • Literature review focusing on platelet-complement interactions.
  • Analysis of current research on immune mechanisms in atherosclerosis.
  • Identification of research limitations and future therapeutic strategies.

Main Results:

  • Platelets are central to atherosclerosis initiation and thrombotic events.
  • Complement exhibits a potentially dual role in atherosclerosis development.
  • Unrecognized cross-talk between platelets and complement significantly impacts atherosclerosis.

Conclusions:

  • The interplay between platelets and complement is crucial in atherosclerosis.
  • Targeting complement pathways presents a potential therapeutic strategy.
  • Further research is needed to fully elucidate and leverage these interactions for disease control.

Related Concept Videos

Formation of the Platelet Plug01:22

Formation 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...
11.0K
Clot Retraction and Fibrinolysis01:16

Clot Retraction and Fibrinolysis

After a fibrin clot is formed, the next step is clot retraction, a vital process facilitated by platelet contractile proteins, such as actin and myosin. These proteins pull the fibrin strands closer together and condense the clot. This action reduces the size of the clot, creating a smaller, denser structure that effectively seals off the damaged vessel. Clot retraction consolidates the clot and helps with wound healing by bringing the edges of the damaged blood vessel closer together.
10.5K
Anticoagulant Drugs: Low-Molecular-Weight Heparins01:30

Anticoagulant Drugs: Low-Molecular-Weight Heparins

Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
2.5K
Extrinsic and Intrinsic Pathways of Hemostasis01:20

Extrinsic and Intrinsic Pathways of Hemostasis

Blood clotting or coagulation involves extrinsic and intrinsic pathways, which ultimately merge into the common pathway, forming a fibrin clot.
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which...
15.9K
Structure and Function of Platelets01:18

Structure 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...
6.6K
Complement System01:27

Complement System

The complement system is a group of approximately 20 plasma proteins that strengthen the body's defenses against infections through opsonization, inflammation, and cell lysis. Opsonization involves coating pathogens with complement proteins, making them more recognizable and facilitating phagocyte engulfment. Certain complement proteins induce inflammation that attracts immune cells to the site of infection. Cell lysis involves the destruction of pathogens through the formation of a...
13.1K