Scottish scientists have created cellular "sniffer dogs" that are capable of hunting down and destroying disease in patients.
Researchers at the Queen’s Medical Research Institute at Edinburgh University modified white blood cells from patients so they can release drugs inside the body and enhance its natural ability to fight off disease.
They claim that by "training" cells in the immune system called monocytes, which are attracted to tissue that is being damaged, they can be used to deliver anti-inflammatory compounds and antibiotics more accurately.
The scientists hope the pioneering technique can be used to treat patients suffering from inflammatory diseases that can destroy the lungs, kidneys and can cause arthritis.
But they also hope to adapt the cells so they can target cancer cells and release chemotherapy drugs in the same way.
Dr John Simpson, senior clinical lecturer in respiratory medicine, said it was possible to insert genes into monocytes that cause them to produce proteins that kill off disease. When the cells are injected back into the patient, they will come into contact with areas of inflammation and release the proteins.
He said: "Monocytes are specifically designed to leave the circulation and go into damaged areas, so they are already going to these trouble spots.
"By inserting a gene sequence into these cells, we can exploit this so they release a protein or a drug where the damage is being done. We can filter out the monocytes from the patient’s blood and insert the gene. The real advantage of this is that we are using the patient’s own cells that already do this job of tracking down trouble in the body, but we are giving them extra weapons to fight with."
Initially Simpson hopes to treat patients suffering from two devastating lung diseases known as ventilator-associated pneumonia and adult respiratory distress syndrome. No effective treatment exists for the illnesses, which kill more than 50% of those who suffer from them. Caused by bacterial infections, they lead to an excessive inflammatory response that can destroy the lungs.
But by using the modified monocytes to release a molecule called elafin, which can dampen the inflammation and kill the bacteria, Simpson hopes it is possible to help patients recover.
Working with staff at Edinburgh Royal Infirmary’s intensive care unit, he has been able to purify monocytes from patient’s blood and modify them. He hopes to begin clinical trials in the next two years.
"Patients who suffer severe trauma from a road accident and require serious surgery often go on to suffer secondary infections as a result of being on a ventilator.
"These are often difficult to treat but we have found that a protein called elafin can not only reduce the inflammatory response, but also kills the infecting bacteria."
The technique for modifying the monocytes was developed by Dr David Kluth, an inflammation expert at Edinburgh University’s new Queen’s Medical Research Institute. He is hoping to use the cells to prevent inflammatory damage to kidneys.
The institute will be officially opened by the Duke of Edinburgh tomorrow.
Scientists there also hope to use modified monocytes to identify disease in its early stages by adding tiny metallic particles to the cells that will show up in high resolution scanners to highlight tissues that are just starting to become inflamed.
Professor Chris Haslett, the institute’s director, said the facility brought together three centres of excellence in inflammation, cardiovascular research and reproductive biology to work together.
The institute, which is the biggest of its kind within Europe, boasts more than 600 elite researchers.
Haslett said: "This work on modified monocytes is a perfect example of how research at the institute is crossing disciplines and allowing scientists to combine their work.
"Here we have cells whose job it is to sniff out infection in the body, and the researchers on this project have given them a new set of teeth to make them more effective."
Andrew Powrie-Smith, head of the British Lung Foundation in Scotland, said: "Patients with respiratory illness are highly susceptible to secondary infections and illnesses.
"We are delighted that research is being done to help these patients as it is vitally needed."