Related Experiment Video
Updated: Mar 1, 2026
10:33
Generation of Alginate Microspheres for Biomedical Applications
Published on: August 12, 2012
22.0K
Alginate microbeads are coagulation compatible, while alginate microcapsules activate coagulation secondary to
Caroline Gravastrand1, Shamal Hamad2, Hilde Fure2
1Centre of Molecular Inflammation Research, and Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
Acta Biomaterialia
|June 4, 2017
Summary
Alginate microspheres for cell therapy show varying coagulation potentials. Surface properties dictate activation pathways, highlighting complement-coagulation cross-talk for intervention strategies.
Area of Science:
- Biomaterials Science
- Immunology
- Translational Medicine
Background:
- Alginate microspheres are explored for cell-based therapies.
- Assessing host reactions like coagulation is crucial for device development.
- Understanding material-specific activation pathways informs prevention strategies.
Purpose of the Study:
- To investigate the coagulation potential of different alginate microsphere formulations.
- To identify the specific coagulation activation pathways involved.
- To explore potential intervention points for mitigating adverse host reactions.
Main Methods:
- Utilized a lepirudin-based human whole blood model.
- Assessed coagulation activation via prothrombin fragments 1+2 (PTF1.2) and monocyte tissue factor (TF) expression.
- Employed specific inhibitors for Factor XII (FXII), TF, complement C3, and C5.
Main Results:
- Sodium alginate-sodium cellulose sulfate-poly(methylene-co-cyanoguanidine) (PMCG) microcapsules rapidly induced coagulation via the contact pathway (FXII).
- Alginate poly-l-lysine (APA and AP) microcapsules induced TF-driven coagulation, involving complement activation (C3/C5).
- Alginate microbeads (Ca/Ba Beads) did not induce significant coagulation activation.
Conclusions:
- Alginate microsphere coagulation potential is surface-dependent, with distinct activation pathways.
- Complement-coagulation cross-talk is a key mechanism for TF-driven activation.
- Targeting complement and coagulation pathways offers intervention points for safer cell-encapsulation devices.
Related Concept Videos
01:06Coagulation
1.5K
Colloidal solids are solid particles suspended in solution. They are usually negatively charged, attracting a compact primary layer of positively charged ions, which attract more counterions to form an electrical double layer. Electrostatic repulsion between the charged double layers prevents the particles from colliding, stabilizing the colloids. These solids are often undesirable because they can contain toxins that are difficult to remove. Coagulation is a technique that helps aggregate and...
1.5K
01:09Coagulation
11.3K
The coagulation phase is a critical part of the body's process to prevent blood loss following injury to blood vessels. It involves chemical reactions that form a clot to seal the injured area. The clotting process begins shortly after injury, within 15-20 seconds for severe damage and 1-2 minutes for minor injuries.
During the coagulation phase, clotting factors, or procoagulants, play a vital role in initiating and progressing the coagulation cascade. This cascade is a series of reactions...
During the coagulation phase, clotting factors, or procoagulants, play a vital role in initiating and progressing the coagulation cascade. This cascade is a series of reactions...
11.3K
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
2.1K
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...
2.1K
01:16Clot Retraction and Fibrinolysis
9.7K
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.
9.7K
01:20Extrinsic and Intrinsic Pathways of Hemostasis
14.1K
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...
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...
14.1K
01:05Introduction to Hemostasis
15.4K
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,...
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,...
15.4K