Peanut and tree nut allergies affect around three million Americans, yet there’s only one approved treatment and it only tackles its severity. And despite the amount of research behind finding a way to counter, or cure, this often deadly condition, there's been only glimmers of hope for sufferers.
But a major breakthrough might be around the corner, with scientists from the University of California, Los Angeles (UCLA) testing a world-first mRNA medicine packaged up in tiny nanoparticles that not only reversed peanut allergies in mice but equipped the body with the microbiological tools needed to stop the often-life-threatening condition developing.
“As far as we can find, mRNA has never been used for an allergic disease,” said study co-author Dr. André Nel, a professor at UCLA. “We’ve shown that our platform can work to calm peanut allergies, and we believe it may be able to do the same for other allergens, in food and drugs, as well as autoimmune conditions.”
Taking a cue from COVID-19 vaccines, the team packaged up mRNA inside a nanoparticle and delivered it to the liver, where it instructed specific cells to tolerate peanut proteins. The researchers focused on the liver in particular because of its tolerance with foreign substances and it being home to antigen-presenting cells, which help train the immune system to tolerate foreign proteins, rather than attack them.
It builds on 2021 research by the team, which saw a nanoparticle deliver a protein fragment, known as an epitope, to the liver to alleviate egg allergies in mice. In 2022 the researchers uncovered the epitope connected to peanut allergies.
“If you’re lucky enough to choose the correct epitope, there’s an immune mechanism that puts a damper on reactions to all of the other fragments,” said Nel. “That way, you could take care of a whole ensemble of epitopes that play a role in disease.”
This is where mRNA came into the picture. In a similar way to how mRNA vaccines encode the COVID-19 spike protein to mount a defense, the mRNA packaged inside this nanoparticle encodes for a specific epitope.
Through several successful trials on mice, the scientists found that the nanoparticle treatment significantly boosted the animals’ tolerance of peanut protein.
The researchers are now confident their treatment will go to clinical trials within three years and that it has the potential to be adapted for allergies, since the mRNA payload can code for different kinds of epitopes. They’re even looking into whether it could be adapted to treat type 1 diabetes.
The study was published in the journal ACS Nano.
Source: University of California, Los Angeles