A new treatment using mRNA has been developed by University of California, Los Angeles immunologists to prevent and treat peanut allergies. The nanoparticle is small, measured in billionths of a meter, and is the first of its kind.
Treatment for Peanut Allergies
The researchers delivered the mRNA to specific cells in the liver, which in turn taught the body's natural defenses to tolerate peanut proteins. In testing the nanoparticle on mice, the study found that it reversed peanut allergies and prevented them from emerging.
The treatment is expected to be safer than existing treatments as it targets specific cells in the liver to reduce the severity of the allergic reaction.
Dr. André Nel, the paper's co-corresponding author, stated that the team had shown that their platform could calm peanut allergies and may be able to do the same for other allergens in food and drugs, as well as autoimmune conditions.
The liver was chosen as the target as the organ is home to cells called antigen-presenting cells, which collect foreign proteins and train the immune system to tolerate them rather than attack when they are detected.
The researchers improved their original nanoparticle by including a sugar molecule on its surface that selectively interacts with antigen-presenting cells.
The selected epitope or epitopes were encoded in part of the mRNA payload, simplifying loading and removing challenges associated with integrating more than one epitope in the nanoparticle.
Lab Test on Mice
To test if the nanoparticle may prevent peanut allergies, the researchers administered it to six mice in two doses separated by a week.
Six other mice received the updated nanoparticle with mRNA inside that did not code for any protein or epitope, six additional mice received the enhanced nanoparticle with no targeting sugar on its surface, and a third set of six mice received no nanoparticle at all.
To make the mice more sensitive to the peanut allergens, scientists began giving the mice a crude peanut protein extract one week following the second treatment.
While more severe symptoms manifested in the control group receiving no treatment and the group receiving a targeted nanoparticle with noncoding mRNA, mice pretreated with the improved nanoparticle displayed lower symptoms than those without targeting sugar.
Clinical Trials in 3 Years
According to Dr. Nel, if more lab tests are successful, the nanoparticle might enter clinical trials in three years.
He went on to say that changing the mRNA payload to one that codes for different epitopes makes it possible to modify the nanoparticle to treat other autoimmune diseases and allergies.
The group is investigating whether the nanoparticle may treat type 1 diabetes, a condition in which the body's immune system assaults cells in the pancreas that help it digest food and produce energy.
If this method successfully treats other illnesses, it might lessen the need for immune-suppressing medications, which could have important effects on patient health.
The study was published in the journal ACS Nano.
