Asthma's more than just a childhood wheeze--it's a chronic inflammatory disease often triggered by allergies that affects the breathing and causes around 284,000 deaths a year worldwide, according to the World Health Organization (WHO). A DNA vaccine in preclinical trials with a group of French researchers could start to bring some relief.
The DNA-based vaccine borrows from the idea of desensitization, where patients receive repeated and increasing doses of an allergen. The researchers, from Inserm and Institut du Thorax, CNRS, started by targeting Derf1 from the dust mite Dermatophagoides farinae, one of the most common allergens in Europe. The vaccine included genes from Derf1 carried in small particles of a synthetic polymer (a nanovector), and is injected into muscle, where the cells make the Derf1 allergen.
In a study of asthmatic mice, the vaccine cut both the mouse's sensitivity to the allergen, and the inflammation linked with the allergy, which can close up the airways.
"Several studies demonstrated the therapeutic potential of this strategy, but we still had to find techniques that were reliable in human beings," explains Bruno Pitard, director of the Biotherapy Innovations team at the Institut du Thorax (CNRS/Inserm/University of Nantes).
According to the WHO, asthma affects around 300 million people worldwide and that number is rising, and around 80% of asthma deaths are in low- and middle-income countries. If a vaccine could reduce this impact, without the need for daily drugs, it could make a real difference in these populations, as well as in the developed world.