Nanoparticles Used to Breach Mucus Barrier in Lungs
Baltimore, MD - Researchers at the Johns Hopkins University School of Medicine, Johns Hopkins University Department of Chemical and Biomolecular Engineering, and Federal University of Rio de Janeiro in Brazil have designed a DNA-loaded nanoparticle that can pass through the mucus barrier covering conducting airways of lung tissue — proving the concept, they say, that therapeutic genes may one day be delivered directly to the lungs to the levels sufficient to treat cystic fibrosis (CF), chronic obstructive pulmonary disease, asthma and other life-threatening lung diseases.
“To our knowledge, this is the first biodegradable gene delivery system that efficiently penetrates the human airway mucus barrier of lung tissue,” says study author Jung Soo Suk, Ph.D., a biomedical engineer and faculty member at the Center for Nanomedicine at the Wilmer Eye Institute at Johns Hopkins. A report on the work appeared in the Proceedings of the National Academy of Sciences on June 29.
The mucus barrier protects foreign materials and bacteria from entering and/or infecting lungs. In healthy lungs, inhaled matter is typically trapped in airway mucus and subsequently swept away from the lungs via beating activities of cilia, or small, hairlike strands, to the stomach to be eventually degraded. Unfortunately, Suk notes, this essential protective mechanism also prevents many inhaled therapeutics, including gene-based medicine, from reaching their target.
His team’s experiments with human airway mucus and small animals, Suk adds, were designed as a proof-of-concept study demonstrating that placing corrective or replacement genes or drugs inside a man-made biodegradable nanoparticle “wrapper” that patients inhale could penetrate the mucus barrier and one day be used to treat serious lung disorders. What’s more, because a single dose might theoretically last for several months, patients would experience fewer side effects common to drugs that must be taken regularly over long stretches of time. Continue>
Posted in: Specialties | September 11, 2013