Fresh insights into how cystic fibrosis affects immune cells could pave the way for new treatments for the condition, Scots researchers believe.
Scientists have discovered that cells in patients with cystic fibrosis that normally defend against infection can also perpetuate damage to the lungs.
Drugs that target these cells could help to stem progression of the disease, the scientists claimed.
A team at the University of Edinburgh, working with researchers in the US and Ireland, focused on immune cells known as neutrophils –part of the body’s first line of defence against infections.
Once an infection has been cleared, neutrophils are usually programmed to die off quietly, so that they do not mistakenly cause damage to healthy tissues.
However, in patients with cystic fibrosis, neutrophils survive longer than they are supposed to and are a key contributor to the lung damage associated with the condition, the experts said.
The team discovered that neutrophils from cystic fibrosis patients are more resistant to the usual mechanism of cell death – a process called apoptosis – with their ability to survive longer directly related to the underlying genetic mutation that causes cystic fibrosis.
Instead, the cells die by a different process, which causes them to disintegrate and expel their damaging contents into the surrounding area of the lung, the team said.
This process promotes inflammation and may therefore promote damage to healthy tissues in the lung.
The researchers said they were able to block this process by treatment with a drug that encourages neutrophils to die by apoptosis, paving the way for new therapies for the disease.
Dr Robert Gray, of the Medical Research Council Centre for Inflammation Research at Edinburgh University, said: “Therapies targeting inflammation are not readily available but are needed for the treatment of cystic fibrosis.
“This work, although at an early stage, will help in the development of new anti-inflammatory treatments for this debilitating condition.”
Cystic fibrosis causes thick mucus to build up in patient’s lungs and digestive tracts. It causes persistent coughs and breathing difficulties, as well as leaving patients vulnerable to recurrent infections.
Around 11,000 people in the UK are currently living with cystic fibrosis.
The research, published in the journal Thorax, was funded by the Medical Research Council and Wellcome.