Researchers reveal mechanism of bacterial keratitis

Researchers from the University of Pittsburgh have shown that a common bacterial contaminant of contact lenses and cases can cause morphological changes in human ocular cells that may contribute to microbial keratitis.

Their research shows that several strains of bacteria can induce epithelial and other eye cells to form large, bulbous membrane structures. The bubble-like growths, called blebs, cause inflammation, ultimately leading to cell death.

Genetic analysis revealed 2 bacterial proteins and their underlying genes are responsible for inducing the morphological changes – a regulatory protein dubbed GumB and a secreted protein, ShIA. Development of new agents which block GumB and ShIA function could prevent future infections and alleviate the reliance on traditional antibiotics.

"Use of contacts lenses is so prevalent, yet until now, we've had limited understanding of how bacteria, associated with contacts lenses and cases, damage cells on the surface of the eye. Our study paves the way for new therapies that alleviate inflammation associated with these often serious eye infections," said Robert Shanks, PhD, Associate Professor, Charles T. Campbell Laboratory of Ophthalmic Microbiology.

The research will be presented at the 2016 ASM Microbe Meeting in Boston, Mass.