Department of Physics, University of Richmond, Richmond, VA 23235, United States of America.
Phys Biol. 2024 Oct 30;21(6). doi: 10.1088/1478-3975/ad899f.
Fibrin fibers are important structural elements in blood coagulation. They form a mesh network that acts as a scaffold and imparts mechanical strength to the clot. A review of published work measuring the mechanics of fibrin fibers reveals a range of values for fiber extensibility. This study investigates fibrinogen concentration as a variable responsible for variability in fibrin mechanics. It expands previous work to describe the modulus, strain hardening, extensibility, and the force required for fiber failure when fibers are formed with different fibrinogen concentrations using lateral force atomic force microscopy. Analysis of the mechanical properties showed fibers formed from 1 mg mland 2 mg mlfibrinogen had significantly different mechanical properties. To help clarify our findings we developed two behavior profiles to describe individual fiber mechanics. The first describes a fiber with low initial modulus and high extensible, that undergoes significant strain hardening, and has moderate strength. Most fibers formed with 1 mg mlfibrinogen had this behavior profile. The second profile describes a fiber with a high initial modulus, minimal strain hardening, high strength, and low extensibility. Most fibrin fibers formed with 2 mg mlfibrinogen were described by this second profile. In conclusion, we see a range of behaviors from fibers formed from native fibrinogen molecules but various fibrinogen concentrations. Potential differences in fiber formation are investigated with SEM. It is likely this range of behaviors also occurs. Understanding the variability in mechanical properties could contribute to a deeper understanding of pathophysiology of coagulative disorders.
纤维蛋白纤维是血液凝固中的重要结构元素。它们形成一个网状网络，作为支架，赋予血栓机械强度。对测量纤维蛋白纤维力学的已发表工作的回顾揭示了纤维可伸展性的一系列值。本研究调查了纤维蛋白原浓度作为导致纤维蛋白力学变异性的变量。它扩展了以前的工作，描述了当使用侧向力原子力显微镜用不同浓度的纤维蛋白原形成纤维时，模量、应变硬化、可伸展性以及纤维断裂所需的力。对机械性能的分析表明，由 1mg/ml 和 2mg/ml 纤维蛋白原形成的纤维具有明显不同的机械性能。为了帮助阐明我们的发现，我们开发了两种行为曲线来描述单个纤维的力学特性。第一种描述了一种具有低初始模量和高可伸展性的纤维，它经历了显著的应变硬化，具有中等强度。用 1mg/ml 纤维蛋白原形成的大多数纤维具有这种行为曲线。第二种描述了一种具有高初始模量、最小应变硬化、高强度和低可伸展性的纤维。用 2mg/ml 纤维蛋白原形成的大多数纤维都具有这种第二种行为曲线。总之，我们看到了由天然纤维蛋白原分子形成的纤维的一系列行为，但纤维蛋白原浓度不同。用 SEM 研究了纤维形成的潜在差异。很可能也会出现这种行为范围。了解机械性能的可变性可能有助于更深入地了解凝血障碍的病理生理学。
