Health Research Board

Dr Roy Sleator, a HRB funded researcher at Cork Institute of Technology(CIT) and Principal Investigator at the Alimentary Pharmabiotic Centre, and his team have developed a very promising new approach to tackle Clostridium difficile (C. difficile), an antibiotic resistant bacteria. Their research involves using one type of bacteria to kill another.

‘In essence, probiotic, or ‘good bacteria’, can be modified to make them fight antibiotic resistant infections in a number of ways’, says  Dr Sleator, who has coined the phrase patho-biotechnology to describe this emerging field of research.

The team have developed ‘good bacteria’ that attack C. difficile in three ways.  Firstly, the probiotic bacteria simply out compete with C. difficile in the gut – rather like grey squirrels in the wild seem to out-compete their smaller red cousins.  Secondly, they can engage in a type of chemical warfare with C. difficile where they attack and kill it. And thirdly, C. difficile produces toxins which cause most of the physical harm, and these probiotic bacteria can literally mop up those toxins in the gut before they cause significant harm. Given that antibiotic resistant bacteria, such as C. difficile and MRSA are among the biggest threats facing our health care systems, this is a major discovery.

In 2008 in the UK, C. difficile was either the underlying cause or mentioned as a factor in almost 6,000 deaths. As far back as 1996, the cost per case in the UK National Health System was estimated to be £4,000, as each patient required an extra three weeks in hospital. There are as yet no exact figures for Ireland, but the financial and social costs are likely to be significant.

According to Sleator, ‘The initial lab work is almost complete and looks very promising. The next step will bring the project to some tests on cells in test tubes or ‘in vitro’. If all goes well with that, we would hope to run pre-clinical trials within two or three years.

Commenting on the research, Mr Enda Connolly says, ‘This discovery has real potential to reduce risk to patients and have a significant and positive impact on the health system in Ireland and much further afield.’

The work also has an added dimension. The Department of agriculture are going to build on the HRB findings and fund further research to apply the technique of a probiotic attack to tackle Crohn's disease; a debilitating disease in cattle caused by Mycobacterium avium subspecies paratuberculosis (MAP). Sleator's C .difficile work has provided the 'proof of concept' for this new research which is being carried out in collaboration with Drs Aidan Coffey and Jim O’Mahony at CIT. MAP is a bacteria that multiplies within white blood cells which are normally an effective component of the bodies immune system. Once one cow is diagnosed with the condition, the whole herd has to be put down.

‘We’re hoping to modify a common probiotic bacteria, Lactobacillus salivarus, make it more resistant to acid and bile, so that more of it can get to, and survive in the intestines, adds Sleator. Once there is gets into the blood stream, and we can switch on a MAP like protein that stimulates the immune system to recognize and kill subsequent MAP invaders. We’re two years into this 4 year project, we’re almost ready to test this out on mice models. If all goes well, we could have a vaccine for MAP within 2 years.'