Study finds new way to prevent infections

DENVER, March 16 (UPI) -- U.S. medical scientists say they have discovered a new method to prevent bacterial infections by using the body's own enzymes.

Dr Quinn Parks and colleagues at Denver's National Jewish Health Hospital said they used enzymes against products of the body's own defense cells to prevent Pseudomonas aeruginosa bacteria from building a protective biofilm that enables the bacteria to avoid both the body's immune mechanisms and antibiotics.

When the body's defense cells, called neutrophils, attack P. aeruginosa, the cell contents -- including a protein called F-actin and the cell's DNA -- are released, Parks said. P. aeruginosa uses those cell proteins as a scaffold to build a protective biofilm that makes such infections very difficult to treat. P. aeruginosa biofilms cause disease in burns, wounds and contact lens infections and are particularly prevalent in the lungs of cystic fibrosis patients.

"We specifically targeted the F-actin protein with a negatively charged peptide and the DNA with the enzyme DNase, which both prevented and disrupted the formation of P. aeruginosa biofilms in the presence of human neutrophils," Parks said. "These results suggest a new combined therapeutic strategy for the treatment of P. aeruginosa infections.

The study appears in the journal Medical Microbiology.