Irish scientists have discovered a new class of drugs which have the potential to improve the treatment of cystic fibrosis (CF) and other chronic conditions.

CF is a hereditary disease that primarily affects the lungs and digestive system. It is caused by a defective gene, which along with its protein product, causes the body to produce unusually thick and sticky mucous.

This mucous clogs the lungs, leading to potentially life-threatening lung infections. It also obstructs the pancreas and stops natural enzymes from aiding the body to break down and absorb food.

Ireland has the highest proportion of people with CF in the world, with around 1,200 people currently affected.
Now, scientists at the Royal College of Surgeons in Ireland (RCSI) have discovered a new class of drugs that mimic the body's own molecules and can fight superbugs that are resistant to antibiotics.

The scientists are the first to have made successful modifications to these molecules - they mimic the molecules that occur in healthy bodies to fight bacteria. This means that they are able to be used as a treatment for infections.

When left unmodified, these molecules can be toxic to the body's healthy cells and bacteria. However, by making small changes to the molecules, they only become active at the site of an infection in the body. No healthy cells are damaged.

The molecules are known as HDPs (host defence peptides). HDPs are either not active enough, or completely absent, in people with CF.

The scientists made the drug so that it only becomes active when it comes into contact with Neutrophil Elastase - an enzyme found in the lungs where bacterial infections occur.

The RCSI team tested the HDPs against Pseudomonas aerinosa, which is the most common bacteria found in people with CF. The HDPs managed to kill the bacteria.

"Our study shows the potential of this new class of antimicrobial therapeutics for use in CF and other chronic illness. As many antibiotics become less effective with time, new treatments such as the HDPs being developed at RCSI will become vital in controlling infection in CF where long-term bacterial infections of the lung reduce life expectancy and quality of life for patients," commented the study's first author, RCSI researcher, Eanna Forde.

Details of these findings were presented at the RCSI Research Day 2014