Assessing the Potential of Nitric Oxide-Releasing Polymers for Bone Regeneration

Project Title: Assessing the Potential of Nitric Oxide-Releasing Polymers for Bone Regeneration

Project Duration: May 25 – August 1, 2015 (10 weeks), 40 hours per week.

Project Mentors

Project Description: Tissue engineering research aims to develop biological substitutes for damaged or diseased tissues, most often using a combination of autologous cells obtained from healthy patient tissue and biomaterial scaffolds that support cell growth and subsequent tissue formation. A large proportion of tissue engineering research is focused on bone tissue engineering to yield healthy bone tissue useful bone fracture repair. In addition to significant bone tissue loss, extensive traumatic injuries, such as those sustained in accidents or combat, are often associated with risk of bacterial infection, which may limit the long-term success of the engineered bone graft. The development of a multi-purpose, tissue-engineered implant, which could support normal bone cell proliferation and osteogenesis (bone formation) while simultaneously minimizing bacterial infection, could improve the success of implanted bone graft materials.

Using nitric oxide (NO)-releasing materials is one approach that has great potential to improve the antimicrobial properties of bone grafts. NO plays an important role in immune response as a potent antimicrobial agent that can target important structures within bacteria cells, including DNA and proteins, after diffusion across their cell membranes. The short half-life of NO (order of seconds), in both blood and tissue, allows localized action without causing any systemic effects that are common with other antibacterial agents. Further, NO has been shown to play a role in bone cell function as a regulator of bone remodeling processes involving osteoclasts and osteoblasts, however, the specific effects of NO on osteoblasts, the cells responsible for bone formation, have been shown to vary depending on NO concentrations used to treat the cells. Therefore, the goal of this project is to develop antibacterial biomaterial scaffolds, based on controlled, NO-releasing polymers that will enhance bone cell function for bone tissue engineering applications.

REU Student Role and Responsibility: Over the course of the project, the student will gain experience in polymer synthesis, materials characterization, and biomaterial scaffold fabrication, specifically focused on preparing controlled-release, NO-based polymer films that may be used as a platform for cell studies. In addition, the student will be trained in aseptic technique, cell culturing, and bone cell biology. Following preparation of the scaffold materials, the student will perform an in vitro cell study to examine the interaction of bone cells with these NO-releasing materials, by evaluating bone cell attachment, proliferation, and differentiation. The combination of these experiences will provide a comprehensive training opportunity in key areas of biomedical research.

Expected Outcome for REU student: The student’s project will serve as a preliminary assessment of the interaction between osteogenic cells and NO-releasing polymers, which will provide a foundation for a longer-term project focused on optimizing polymer scaffold design for bone regeneration. Findings obtained from the student’s project will likely contribute to the development of a manuscript intended for submission to a journal such as Biomaterials, Journal of Materials Chemistry B, or Journal of Biomedical Materials Research: Part A, in addition to a conference abstract submission for presentation at a professional society meeting such as the annual meeting of the Biomedical Engineering Society.

Gianino REU Poster