Scaling theory of fibrin polymerization.
Research article published in Physical review. E (2024)
Abstract
Fibrin polymerization is responsible for the formation of blood clots and is used in many biomedical applications. Considering polymerization as a dynamic phase transition, we constructed a scaling theory of fibrin networks formation. We show that in the transient state, protofibrils and branched clusters are self-assembled as a result of diffusion-controlled reactions with free fibrin monomers. The rate of reactions increases with initial concentrations of fibrinogen and thrombin. Protofibrils and clusters aggregate laterally, forming fibers, the elongation of which leads to their crosslinking to form a fibrin network. We calculated the network structure for different ratios of lag time and fibrinogen activation time. At a low ratio of fibrinogen and thrombin concentrations, sparse networks of thick and long fibers are formed, whereas at a high ratio, dense networks of thin and short fibers. The predicted concentration dependences of network parameters are in agreement with experimental data.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Fibrin polymerization is responsible for the formation of blood clots and is used in many biomedical applications. Considering polymerization as a dynamic phase transition, we constructed a scaling theory of fibrin networks formation. We show that in the transient state, protofibrils and branched clusters are self-assembled as a result of diffusion-controlled reactions with free fibrin monomers.
Why This Matters for Hirudotherapy
This theoretical paper builds a scaling/physics model of fibrin network formation, treating polymerization as a dynamic phase transition in which protofibrils and branched clusters self-assemble through diffusion-controlled reactions with free fibrin monomers and then aggregate laterally into fibers that crosslink into a network. It shows that the ratio of fibrinogen and thrombin concentrations governs network architecture (a low ratio yields sparse networks of thick, long fibers; a high ratio yields dense networks of thin, short fibers), with predicted concentration dependences matching experimental data. This is relevant to the medicinal-leech drug-discovery story because leech secretome anticoagulants (notably the direct thrombin inhibitor hirudin and related molecules) act on thrombin-driven fibrin generation, so a quantitative framework for how thrombin concentration shapes clot architecture helps explain how thrombin-targeting leech compounds could alter clot structure, not just clot presence. Caveat: this is a computational/theoretical modeling study of clot physics with no experimental leech component and no clinical data, so its relevance is mechanistic and indirect.
Citation
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