Hanover, NH--Dartmouth Medical School researchers have devised a novel approach for thwarting the relentless bacterial infections that thrive in the lungs of people with cystic fibrosis (CF), unlocking new possibilities against a tenacious and toxic hallmark of the common genetic disease.
Combining a mainstay antibiotic with drugs to deprive the bacteria of iron, which facilitates their persistent growth, appears to boost infection killing, they found.
Their research, reported in the American Journal of Respiratory Cell and Molecular Biology online and scheduled for publication, builds on the collaborative expertise of DMS microbiology and lung physiology labs studying cystic fibrosis infections.
Cystic fibrosis patients are plagued by infections of the bacteria Pseudomonas aeruginosa. Their mucous-clogged lungs are fertile incubators for the bacteria to breed and cluster in slimy communities called biofilms that become increasingly drug resistant and damaging. Tobramycin, the antibiotic routinely used against the microbes, can control, but not efficiently eliminate Pseudomonas established on CF airway cells.
Last year, the DMS researchers reported that it took far more tobramycin to destroy biofilm pockets than can be delivered to the lungs. Using a surrogate tissue culture system they created to simulate human airways, they determined that up to 10 times the maximum tobramycin dosage was needed. They were also studying iron overload in CF lungs. Airway cells with the CF gene mutation release more iron, and the bacteria depend on that iron to form their resilient biofilms, the investigators discovered.
Now, applying their findings to the clinical front, the team demonstrated that two agents already approved by the Federal Drug Administration to treat acute iron poisoning or overload can enhance the ability of tobramycin against Pseudomonas infection.
"The beauty is that we are mixing FDA-ap
|Contact: Sue Knapp|