O17 - Evaluation of the sex-dependent effects of fibrin-specific nanogels

Saturday, October 11, 2025

10:00 AM - 11:00 AM PDT

Location: Exhibit Hall F, G & H

Presenting Author(s)

Preethi Coulter

Undergraduate Research Assistant
Lampe Joint Department of Biomedical Engineering at North Carolina State University and University of North Carolina at Chapel Hill
Chapel Hill, North Carolina, United States

Co-Author(s)

HC

Halle J. Cantor

PhD Candidate
North Carolina State University, United States
EB

Elizabeth Byrnes

Graduate Student
North Carolina State University, United States
MD

Michael Daniele

Faculty Researcher
University of North Carolina at Chapel Hill & North Carolina State University, United States

Primary Investigator(s)

Ashley C. Brown

Lampe Distinguished Professor
North Carolina State University and University of North Carolina at Chapel Hill
Raleigh, North Carolina, United States

Introduction: : Disseminated intravascular coagulation (DIC) is a condition in which excessive clotting occurs. These clots can block blood flow leading to organ failure. Furthermore, the consumption of clotting factors leads to bleeding risks. DIC can be caused by infection, trauma, or shock.
Our lab has developed fibrin-specific nanogels (FSNs), which are a type of core-shell nanoparticle. Fibrin-targeting antibodies are conjugated to the shell of the nanoparticle enabling clot-targeting and enhanced clot formation. Injectable, targeted drug delivery is particularly ideal for treating DIC, as drug-loaded FSNs can travel intravenously to quickly address the systemic effects of DIC as inappropriate clotting occurs rapidly throughout the vasculature.
In rat models of sepsis-induced DIC, we have observed that FSNs loaded with anti-clotting drugs (tissue plasminogen activator and antithrombin-III) improve ex vivo clotting in male rats but not in female rats. In the male rats with DIC, there was a clear, direct correlation of clot fiber density improvement relative to the FSN dosage administered. However, female DIC rats did not share this trend, and even with the highest FSN dosage, clot fiber density did not improve. This study aims to further investigate the significance of and the factors that influence the differences in male and female responses to FSNs across species. This project utilized male and female samples of human blood to form static plasma clots in custom microfluidic devices and then evaluated how well unloaded FSNs infiltrate clots and enhance clot formation when flowed across the clot interface.

Materials and

Methods: : A Sylgard 184 Silicone Elastomer Kit was used to create microfluidic devices. Elastomer was mixed with the curing agent at a ratio of 10:1 and poured into a custom 3D-printed mold. The polydimethylsiloxane (PDMS) was baked at 80°C for 2 hours, plasma-bound to slides, then baked again at 80°C for 48-72 hours. Green fluorescent clots were polymerized from the combination of pooled male or pooled female platelet-poor plasma (PPP), AlexaFluor 488-labeled human fibrinogen, calcium chloride, and thrombin, then allowed to polymerize in the devices for 2 hours (Sheridan et al. 2024). A flow buffer of red fluorescently-labeled FSNs in an actively polymerizing clot solution was flowed through the device across the clot interface and the attachment of FSNs to the clot and changes in clot density were quantified.
Images of the clots over time were processed with ImageJ to create a binary image of the clot. White and black pixels were quantified and the percentage change in clot fiber density and FSN accumulation was calculated for each sample. Results comparing male and female clots for each species were compared with student’s T-tests and comparisons between species were made with 1-way ANOVAs and Tukey’s multiple comparisons tests in GraphPad Prism for statistical significance.

Results, Conclusions, and Discussions:: From the quantification of the green fluorescent clot images, we found that the change in clot density between human males and females was not significantly different; however, male clots trended towards greater changes in clot density. In the red fluorescent clot images, we observed a trend of increased FSN accumulation in male clots compared to female clots. Increasing our number of male and female samples will power our analysis and enable us to further elucidate whether FSNs have a higher clot infiltration rate and ability to enhance male clot density compared to female clots. Ongoing work is characterizing outcomes in horses and pigs. We expect that FSN clot infiltration and subsequent enhancement of clot density will be increased in males across species.

Acknowledgements and/or References (Optional): :