Scientists have used gene therapy to 'switch off' the immune response that causes asthma, and are hopeful that the same technique could be used to target other severe allergies to peanuts, bee venom, and shellfish,keeping them at bay for life.

The research, which has so far seen success in animal trials, works byerasing the memory of the cells responsible for causing an allergic reaction, and if replicated in humans, could offer a one-off treatment for allergy patients.

"The challenge in asthma and allergies is that these immune cells, known as T-cells, develop a form of immune 'memory', and become very resistant to treatments,"says lead researcherRay Steptoefrom the University of Queensland (UQ) in Australia.

"We have now been able 'wipe' the memory of these T-cells in animals with gene therapy, de-sensitising the immune system so that it tolerates the [allergen] protein."

An allergic response is a hypersensitive immune reaction to a substance that is normally harmless. When people are exposed to their allergic trigger, it can cause anything from itchy eyes and a runny nose to - in the most extreme cases -death.

Asthma is a common allergic response of the airways affecting 2.5 million Australiansand hundreds of millions around the world. About 80 percent of people who experience asthma in Australia are susceptible to hay fever - an allergic response to rye grass pollen.

"When someone has an allergy or asthma flare-up, the symptoms they experience results from immune cells reacting to protein in the allergen," says lead researcherRay Steptoefrom the University of Queensland (UQ) in Australia.

While previous research has looked into using nanoparticle 'trojan horses' to smuggle the allergen past the immune system, and at new immunotherapy approaches, right now, the most effective treatment for people suffering from allergies is to simply avoid all known triggers.

To figure out a better way, Steptoe and his teamtook bone marrow from mice that had been genetically modified to have a resistance against asthma caused by rye grass pollen, and transplanted the bone marrow into unmodified mice.

"We take blood stem cells, insert a gene which regulates the allergen protein, and we put that into the recipient," says Steptoe.

"Those engineered cells produce new blood cells programmed to express the protein and target specific immune cells, which 'turn off' the allergic response."

Even though this study only looked at asthma, the researchers hope that the same approach could be used to provide protection against other common allergies - food and otherwise.

"Our work used an experimental asthma allergen, but this research could be applied to treat those who have severe allergies to peanuts, bee venom, shellfish and the like," Steptoe said.

But before we start throwing our puffers in the bin, the studies still have to be replicated in human trials, and that's where things get much more complicated.

"In the real world, unfortunately, it's not just usually a single allergen protein [that causes an immune response]. There might be several proteins that you might be allergic to and you'd have to target each of those proteins," Steptoe told ScienceAlert.

"We're currently doing experiments to see if we can turn off multiple response at the same time."

The research is published in JCI Insight.

Go here to read the rest:
Gene therapy has been used to 'switch off' asthma symptoms - ScienceAlert

Comments are closed.