SCIENTISTS in Nantes have developed a promising vaccine for asthma.
The respiratory condition has become twice as common over the last 10 years, affecting 300 million people worldwide and causing cause a quarter of a million premature deaths a year.
Asthma causes recurring bouts of inflammation of the airways, with coughing, wheezing and shortness of breath. It is thought to have both genetic and environmental components, but attacks are usually triggered by allergens.
The new method is a high-tech version of the “desensitisation” technique, which consists of administering small, but increasing, doses of an allergen to get the body used to it. That has been hit-and-miss in asthma treatment so far, but the new method uses a very precise approach that has proved effective on trials with mice.
Specific DNA sequences of one of the main allergens (usually carried by mites) are introduced directly into the muscles via a nanovector – that is, they are inserted into thousands of tiny spheres made of biodegradable polymer which carry the active substance to where it is needed.
Two injections, three weeks apart, were found to greatly reduce the sensitivity of the airways to the presence of the allergen.
“These new results validate the potential of this new nanovector for DNA vaccination,” stated research body Inserm, which is running the project.
Clinical trials on people are expected to start in about three to four years.
Marin Conic www.fotolia.com