Cystic fibrosis is a genetically inherited life-limiting disorder that affects 30,000 people in the US and 70,000 people worldwide. Increased mucus viscosity in the lungs of CF-afflicted individuals prevents the clearance of bacteria via normal means (e.g., ciliary beating and coughing), thereby allowing proliferation and the formation of biofilms. Bacterial biofilms degrade the lungs and are the primary cause of CF morbidity and mortality. While gene therapies could potentially cure CF, there are over 1,800 genetic mutations which cause CF, each of which would require the development of a specific drug. Therefore, development of therapeutics that are more effective than current treatments at eliminating bacterial biofilms represents a more cost effective and timely approach to increasing the life expectancy of people with CF. The goal of this project is to develop water soluble chitosan scaffolds that release nitric oxide (NO), an endogenous antibacterial agent, and effectively eradicate CF biofilms. The efficacy of these novel NO-release scaffolds will be tested against CF-relevant bacteria strains in conditions that mimic the CF lung. We hypothesize that disulfide-reducing reactivity of NO will also reduce the mucus viscosity, potentially enhancing the action of subsequent NO treatments and improving the ability of the innate immune system to further control bacterial levels in the lungs. The effects of NO and NO-release scaffold composition on mucus viscosity will thus be systematically studied to determine NO's potential as a dual action CF therapeutic. These macromolecular scaffolds represent the first NO-based therapeutics suitable for pulmonary delivery, and are thus highly innovative.

Public Health Relevance

Cystic fibrosis is an inherited genetic disorder that results in a significantly shortened life span (average of 37 years) primarily due to persistent bacteria infections in the lung and associated degradation of lung function. The objective of tis project is to develop water - soluble nitric oxide (NO) - release scaffolds to alter mucu viscosity and eradicate bacteria biofilms in the CF lung.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI112029-02
Application #
8968231
Study Section
Drug Discovery and Mechanisms of Antimicrobial Resistance Study Section (DDR)
Program Officer
Lu, Kristina
Project Start
2014-12-01
Project End
2016-11-30
Budget Start
2015-12-01
Budget End
2016-11-30
Support Year
2
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
608195277
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Reighard, Katelyn P; Ehre, Camille; Rushton, Zachary L et al. (2017) Role of Nitric Oxide-Releasing Chitosan Oligosaccharides on Mucus Viscoelasticity. ACS Biomater Sci Eng 3:1017-1026
Lu, Yuan; Shah, Anand; Hunter, Rebecca A et al. (2015) S-Nitrosothiol-modified nitric oxide-releasing chitosan oligosaccharides as antibacterial agents. Acta Biomater 12:62-69
Reighard, Katelyn P; Hill, David B; Dixon, Graham A et al. (2015) Disruption and eradication of P. aeruginosa biofilms using nitric oxide-releasing chitosan oligosaccharides. Biofouling 31:775-87
Reighard, Katelyn P; Schoenfisch, Mark H (2015) Antibacterial Action of Nitric Oxide-Releasing Chitosan Oligosaccharides against Pseudomonas aeruginosa under Aerobic and Anaerobic Conditions. Antimicrob Agents Chemother 59:6506-13