Your genome is sort of like a library—with each gene an instruction manual for making proteins. Bad news is, you can’t return a book and take out a new edition. But the technique of gene therapy allows you to revise your copy of the book, so to speak…giving you the ability, potentially, to make new and different proteins.

Now scientists have experimented with a new way to make text revisions—by inhaling the changes. They tested the concept by having mice breathe in genetic material called messenger RNA, or mRNA. For the test, the mRNA included instructions to manufacture luciferase—the stuff that lights up in fireflies. 

The researchers packaged the mRNA with a degradable polymer, to trick the mice's lung cells into accepting the package. And once the cells gobbled it up, they began to glow—proving that inhaling mRNA is an effective way to kick-start the production of new and novel proteins, like the firefly enzyme. 

The scientists also repeated the experiment in mice whose cells had been genetically engineered to turn permanently red if they received a copy of mRNA—making it possible to count the proportion of cells affected by a dose. The proof of concept is in the journal Advanced Materials. [Asha Kumari Patel et al., Inhaled Nanoformulated mRNA Polyplexes for Protein Production in Lung Epithelium]

Of course, the point isn't to make mice glow. Instead, one idea is to use this technique to help cystic fibrosis patients. People with CF have a genetic mutation that causes a buildup of sticky mucus in their lungs. Several of the study authors work with a publicly traded biotech company called Translate Bio, which is conducting phase 1 and 2 trials to determine if inhaling messenger RNA could provide a genetic fix for cystic fibrosis. Regardless of the particular case of CF, the luciferase example shows that inhalation genetic therapy could be an inspiration. 

—Christopher Intagliata

[The above text is a transcript of this podcast.]