# How do early stages of fibrin fiber assembly affect clot structure and lysis > **NIH NIH R15** · EAST CAROLINA UNIVERSITY · 2024 · $455,082 ## Abstract Project Summary/Abstract The broad, long-term objective of the proposed research is to determine the mechanisms regulating fibrin and fibrinogen function, with the goal of improving the diagnosis and treatment of cardiovascular disease. In so doing, we plan to train the next generation of scientists with an interdisciplinary skill set. In this specific proposal, we will study the polymerization, structural properties, and enzymatic digestion of fibrin fibers. Fibrin fibers polymerize into a 3-D gel after thrombin converts fibrinogen to fibrin. The structural properties of fibrin are regulated by many factors such as enzyme concentrations, and altered fibrin structures have been linked to pathologies such as diabetes. Although fibrin polymerization has been studied for decades, there remains a crucial gap in our understanding of how early fibrin polymers transition into a fully-formed gel. Because the transitional period likely determines the final gel structure, this gap in knowledge prevents a direct association between polymerization processes and the biochemical and pathological conditions that result in altered clot structures. In this research project, we will utilize recently developed approaches to determine mechanisms of fibrin polymerization. We hypothesize that these polymerization processes propagate throughout the entire coagulation process, affecting both the final gel structure and fibrin’s resistance to enzymatic digestion. Testing this hypothesis will rely heavily on undergraduate student researchers, providing training in molecular biology, biochemistry, biophysics, mathematical modeling, and blood coagulation. Specific Aim 1: Make direct observations of fibrin polymerization and quantify polymerization processes and kinetics. Using high framerate, high resolution fluorescent microscopy techniques combined with advanced image analysis tools, and atomic force microscopy, we will observe and quantify fibrin polymerization. In so doing, we will measure rates of fiber growth, changes in fiber stiffness, and branch point formation for the first time. Our experimental results will be tested against mathematical models to differentiate competing hypotheses about these processes. Specific Aim 2: Validate fibrin structural properties with multiple techniques and correlate the final structural properties of fibrin gels with the early stages of fibrin formation. Using two or more different techniques, we will measure fibrin structural properties including fibrin fiber length, diameter, and mass-length ratio and network pore size and branch point density. These network structural properties will be correlated with polymerization processes to identify which aspects of polymerization determine fibrin structures. Specific Aim 3: Determine how early clot structures affect lysis. We will measure the fibrinolysis rates of whole networks and individual fibers within the network using novel fluorescence-based microscopy app... ## Key facts - **NIH application ID:** 10875762 - **Project number:** 2R15HL148842-02 - **Recipient organization:** EAST CAROLINA UNIVERSITY - **Principal Investigator:** Nathan E Hudson - **Activity code:** R15 (R01, R21, SBIR, etc.) - **Funding institute:** NIH - **Fiscal year:** 2024 - **Award amount:** $455,082 - **Award type:** 2 - **Project period:** 2019-07-01 → 2027-03-31 ## Primary source NIH RePORTER: https://reporter.nih.gov/project-details/10875762 ## Citation > US National Institutes of Health, RePORTER application 10875762, How do early stages of fibrin fiber assembly affect clot structure and lysis (2R15HL148842-02). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10875762. Licensed CC0. --- *[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*