Nanomedicine is a rapidly developing field that holds great promise for transforming healthcare. It involves the manipulation and manufacture of materials and devices at the molecular scale (between 1 and 100 nanometers in size). This opens up previously unthought-of possibilities for diagnosis, treatment, and prevention of diseases. RNA-based nanomedicines have recently demonstrated their revolutionary potential with the SARS-CoV2 vaccines.
What is mRNA?
Messenger RNA (mRNA) is a short-lived conveyor that transforms information from the DNA (deoxyribonucleic acid) – the building blocks of life – into proteins. This process is fine-tuned by small RNA species that can stimulate or inhibit protein production from mRNA. Together, mRNA and small RNAs offer the opportunity to start and stop protein production at will. Almost all the actual functions in cells are performed by proteins, and faulty protein production is found at the centre of many diseases. This makes RNA-based therapy very powerful.
The key to RNA nanomedicines lies in the code: simply changing the sequence in a string of four genetic ‘letters’ will make fundamentally different medicines. Interestingly, the remainder of these nanomedicines, and the way to make them, can be kept unchanged as the fundamental characteristics of RNA remain the same. This way, safe and efficacious medicines and vaccines can be developed and produced faster, cheaper, and more precise than ever before.
mRNA are very fragile molecules that are hard to deliver intact to their site of action inside cells as they are naturally susceptible to degradation, may trigger the body’s immune response, and cannot spontaneously cross the cell membrane. For this, a coating needs to be developed that is large enough to accommodate, encapsulate, and protect the RNAs while still being small enough to be taken up by cells. The development of appropriate nanosized carriers to bring therapeutics to their destination is an exciting field with enormous potential for improving human medicine.