The humble garden snail could provide us with some ammunition in the fight against aggressive bacteria, according to two researchers from the United Kingdom. Intrigued how garden snails spend their lives sliding over dirt and coming into contact with deadly bacteria, yet don’t seem affected, Sarah Pitt, Ph.D. and Alan Gunn set out to discover why. It seems the answer lies in the mucus snails excrete. After analysing snail mucus, Pitt, principal lecturer in the School of Pharmacy and Biomolecular Science at the University of Brighton, and Gunn, subject lead for biosciences in the School of Natural Sciences and Psychology at Liverpool John Moores University, discovered four new previously unknown proteins. What’s more exciting is that two of these proteins appear to have strong antibacterial properties – especially against aggressive strains of Pseudomonas aeruginosa, a bacterium that causes dangerous lung infections in people who have cystic fibrosis. Speaking about the findings of their research, which appears in the British Journal of Biomedical Science, Pitt said: “In previous work, we found that the mucus consistently and convincingly inhibited the growth of one species of bacterium P. aeruginosa, a tough bacterium that can cause disease, but it did not seem to work against other bacteria. “So, in this study,we tried all the control strains of P. aeruginosa we had available in the lab here at the university as well as five strains taken from patients with [cystic fibrosis] who had lung infections with this bacterium.” The new discoveries could open up new possibilities in the fight against bacterial infections.
A British teenager has become the first person in the world to have a drug-resistant bacterial infection treated by genetically engineered viruses. Isabelle Holdaway, 17, was given just a 1% chance of survival after a double lung transplant to treat her cystic fibrosis left her with an intractable bacterial infection that could not be treated with antibiotics. Her arms, legs and buttocks had numerous big, black, festering lesions where the bacteria were pushing up through her skin. She finally ended up in intensive care after her liver began to fail. Every previous patient in Isabelle’s situation died – some within a year, despite aggressive treatment. Desperate for a solution, Isabelle’s mother researched alternative treatments online and came across phage therapy. It’s not new; doctors have been using it for nearly a century, but its use has been eclipsed by antibiotics because they are much easier to use. Isabelle’s care team at Great Ormond Street Hospital contacted Prof Graham Hatfull at the Howard Hughes Medical Institute, in the US, who had the world's largest collection of phages (approximately 15,000). Hatfull and his team identified three potential phages that would be effective in tackling Isabelle’s bacterial infection and genetically modified two of them to make them more effective. Isabelle was injected with the cocktail of phages twice daily and they were also applied to the lesions on her skin. Within just six weeks, a liver scan showed that the infection had essentially disappeared. Phage therapy involves injecting bacteria-killing viruses into a patient’s body which track down, infect and ultimately kill bacteria. The phages hijack the bacterial cell and turn it into a phage factory until the viruses burst out of the bacteria killing it in the process. While Isabelle’s fatal infection has not been completely cured, it is under control and she is beginning to lead a normal life. She still has two infusions of phages every day and is currently waiting for a fourth phage to be added to the mix, which will hopefully clear the infection completely.
A study of almost 600,000 people has found that some individuals are born with "superhero DNA", which has the ability to cancel out certain diseases such as cystic fibrosis. According to the findings of the US research, 13 people from the study group were found to be resistant to severe inherited diseases. The hope is that there could be more people across the world and that their DNA could lead to life-changing new treatments being developed. The 13 unnamed individuals were found to carry genetic mutations which are linked to a number of childhood diseases. However, against the odds, they all remained healthy. But the researchers do not know who these people are because of the anonymity issues associated with studying DNA stored in data banks. Each one of the 13 should have been susceptible to so-called Mendelian disorders, which usually begin in early childhood and are the result of defects in a single gene. Cystic fibrosis is an example of a Mendelian disorder. "Millions of years of evolution have produced far more protective mechanisms than we currently understand," said Dr Eric Schadt from the Icahn School of Medicine at Mount Sinai Hospital in New York. The findings of the study were recently published in Nature Biotechnology.
Doctors say that a “ground-breaking” cystic fibrosis therapy could dramatically improve the quality of life for sufferers of the condition. Patients usually die before they reach the age of 40 as they’re left prone to infection from the mucus that clogs and damages their lungs. But now, a major clinical trial on some 1,108 patients, the results of which were published in the New England Journal of Medicine, revealed that a combination of drugs had the ability to bypass the genetic errors that caused the condition and increase life expectancy as a result. In the UK alone, one in every 2,500 babies are born with cystic fibrosis and the Cystic Fibrosis Trust believes the new findings could “improve the lives of many”. A genetic condition, the DNA of cystic fibrosis sufferers contains an error which means the individual is unable to control salt and water levels in their lungs. A thick mucus forms and inexorably damages the lungs. Antibiotics have been used historically to prevent infection, but nothing has been developed to address the underlying problem for most sufferers. Lumacaftor and ivacaftor are the two drugs which when combined, improved the lung function of those patients that received them over the course of a 24-week trial. It was also reported that patients gained weight during the trial, something which was attributed to the mucus lining in the gut being affected too. Professor Stuart Elborn, who headed up the Queen’s University, Belfast part of the trial, said: “It is not a cure, but it is as remarkable and effective a drug as I have seen in my lifetime.” Photo credits: Discover magazine, The New York Time Magazine