New method to fight bacterial infections linked to contact lenses

WASHINGTON - Scientists have found a new method to fight bacterial infections associated with contact lenses.

The method, discovered by researchers at National Jewish Health and the University of Texas Southwestern Medical Center, may also have applications for bacterial infections associated with severe burns and cystic fibrosis.

The eye normally fights infections through a variety of defense mechanisms including blinking of the eyes, which helps remove bacterial organisms from the surface of the eye. Contact lenses, however, inhibit the effectiveness of blinking eyelids.

The researchers confirmed earlier findings that cellular debris from immune cells fighting the infection actually provide the raw materials for the biofilm - DNA, actin and histones. So, they used the enzyme DNAase together with negatively charged poly aspartic acid to break down the chemical bonds of these elements that support the biofilm.

This treatment reduced biofilms on the contact lenses by 79.2 percent. The same treatment reduced infection of the cornea in an animal model by 41 percent. There was no evidence of any harm caused by the treatments.

“These are vey promising early results that point to potentially new methods for removing bacterial biofilms from contact lens surfaces, thereby reducing the risk of microbial keratitis, as well as the for the treatment of infections by Pseudomonas that are associated with cystic fibrosis and severe burns,” said Danielle Robertson, first author and Assistant Professor of Ophthalmology at UT Southwestern, and first author on the study.

The results have been published online in the journal Investigative Ophthalmology and Visual Science. (ANI)