A team of Australian researchers believe they’re taken the first step towards preventing babies from developing asthma – by giving at-risk infants an immune-training medicine known as OM-85.
What is OM-85?
OM-85 is a combination of molecules extracted from the walls of bacteria that commonly cause respiratory infections. The medication is not yet available in Australia, but has been widely used in Europe and South America for decades, often under the brand-name Broncho-Vaxom.
In our gastrointestinal tracts, microbiota (our inherent, bodily bacteria) “train” the immune system, by sending a stream of signals through the mucosal lining into the tissues near immune cells.
OM-85 works to enhance this ‘immune training’ process. One of the ways it does this is by stimulating the maturation of regulatory T-cells in the lymph glands of the upper intestine – once fully matured, these pathogen-fighting cells can migrate to other mucosal surfaces in the body to bolster its defences. This process is key in the protection of the lungs and airways.
So, OM-85 is a potent preventative medicine, which can be given pre-emptively to people who are at risk of more severe consequences if they contract a respiratory infection.
Giving at-risk babies a fighting chance
“Severe respiratory viral infections in early life are linked to asthma development later in life,” says PhD student Niamh Troy, the study leader. “Our previous research found it was possible to reduce the severity of respiratory infections in babies using OM-85, but for this study we wanted to understand how it changed their immune system.
“We were missing a piece of the puzzle. Understanding why this treatment works is critical to progressing this therapy into routine clinical care – and hopefully one day preventing children from developing asthma.”
Using systems biology, which integrates biology with computer science, Troy and her team looked at samples from babies given either OM-85 or a placebo, to see how their immune genes functioned when faced with an infection.
“We found that the babies who received the treatment had a stronger immune ‘alarm’ system that sent a signal to the immune system in the early stages of infection. We also found those babies had lower inflammatory responses to infection,” explains Troy.
“Essentially, we found the treatment ‘trained’ the babies’ immune defences, which helped them to be able fight off severe infections. It didn’t stop the usual colds and sniffles that babies get, but it stopped these infections getting really bad. And it is these bad infections that can increase the risk of asthma later on.”
This is important, because changes in the way we live in the modern era may be eroding some babies’ abilities to develop robust immune responses.
“Our innate immune system is sensitive to our environment, and the harmless bacteria that we are exposed to help to keep our innate immune system fit,” says Troy. “But our lifestyles have changed and our innate immune system may not be getting the signals that it needs, especially in early life.”
The research was undertaken at the Wal-yan Respiratory Research Centre, a partnership between Telethon Kids Institute, the Perth Children’s Hospital Foundation and Perth Children’s Hospital. The findings will help inform the Wal-yan Centre’s goal of developing a vaccine-like approach to preventing asthma.
“By understanding how OM-85 helps babies to fight off respiratory infections, we’re one step closer to understanding how to prevent them going on to develop asthma,” Ms troy said.
“We are really excited about these findings. We hope to extend our research into larger trials and work with international collaborators with the aim of making this treatment available to all babies that are at risk of asthma.”
The study is published in the Journal of Allergy and Clinical Immunology.