Poster L16 - Towards an Inhalable Tissue-Specific Extracellular Matrix-based Substrate for Targeted Laryngeal Tracheal Regeneration.

Saturday, October 26, 2024

10:00 AM - 11:00 AM EST

Location: Exhibit Hall E, F & G

Presenting Author(s)

Fiona Kowalkowski (she/her/hers)

Undergraduate Student
Joint Department of Biomedical Engineering, North Carolina State and University of North Carolina-Chapel Hill
Oak Brook, Illinois, United States

Co-Author(s)

Ramair Colmon, BS

Graduate Student
Joint Department of Biomedical Engineering, North Carolina State and University of North Carolina-Chapel Hill, United States
Donald Freytes

Associate Professor
Joint Department of Biomedical Engineering, North Carolina State and University of North Carolina-Chapel Hill, Raleigh, NC, United States of America, United States

Introduction: Every year, about 28 million Americans experience voice problems related to vocal cord injuries, such as cysts, paralysis, and scarring. These injuries can result from various causes, including scarring and airway narrowing due to procedures like intubation. Surgery to treat these vocal cord injuries often leads to more scarring, worsening the patient's condition. Current treatments are not very effective, and there are limited options for regenerating the vocal cords. Therapists sometimes use biomaterials to help the vocal cords function better, but these methods could be more successful in the long run. Our research lab has developed a gel made from the extracellular matrix of pig vocal cords that contains proteins and peptides, which have shown anti-scarring properties in laboratory tests. These gels are better than other gels for their ability to promote tissue regeneration, reduce scarring, and are less likely to cause an immune reaction when tested in animals. However, using these gels requires invasive procedures such as surgery and implantation, which may need to be repeated multiple times. Our goal is to create a less invasive version of this gel that can be turned into a mist and inhaled while still retaining its beneficial properties in the body.

Materials and

Methods: The Nebulizable ECM (NebECM) formulation was created by producing and then analyzing a solubilized version of the VFLP-ECM. This solubilized form could be directly delivered to the upper respiratory tract (URT) using a commercially available ultrasonic mesh nebulizer. We used Ultraviolet-Visible Spectroscopy to determine the mass concentration of the solubilized VFLP-ECM formulation before and after nebulization. Dynamic Light Scattering techniques were utilized to measure the size of ECM particles in the formulation. To test the compatibility of NebECM, we cultured Human Vocal Fibroblasts (HVOX) with Neb-ECM and growth medium for 24 hours. Then, we assessed changes in cell metabolic activity and viability using MTT, Pico Green, and LIVE/DEAD assays. Furthermore, we examined the potential activation of HVOX into myofibroblasts by analyzing gene expression. This was accomplished through quantitative real-time polymerase chain reaction (RT-qPCR), with cells cultured with Neb-ECM and growth medium in the presence of TGF-β1 cytokine for 24 hours before isolating RNA for the RT-qPCR assay.

Results, Conclusions, and Discussions: The NebECM substrate, with particle sizes around 1 micrometer in diameter, has shown promising results in cytotoxicity studies. These results indicate it does not hinder cell metabolism or contribute to apoptosis. Although gene expression studies are still underway, we are optimistic that the NebECM will exhibit a modulatory response by fibroblasts, similar to the VFLP-ECMh.

Acknowledgements (Optional):