Welcome to Innovations in Medicine on ReachMD, sponsored by Moderna. On this episode, we’ll hear from Dr. John Cooke, Chair of the Department of Cardiovascular Sciences at the Houston Methodist Research Institute. He’s also the Director of the Center for Cardiovascular Regeneration and Medical Director of the RNA Therapeutics Program in the Houston Methodist DeBakey Heart and Vascular Center in Houston, Texas. Let’s hear from Dr. Cooke now.
Message RNA is basically a copy of the DNA, and a copy of a particular gene within the DNA, or even a portion of a gene within a DNA. So whereas the DNA is in the nucleus, we want to keep it pristine. The message RNA gets transcribed in the nucleus and exported out of the cytoplasm. It’s basically a transient copy of the DNA. It gets transported out into the cytoplasm where it gets acted upon by ribosomes which read that code of the RNA and generate a protein. So essentially, what the RNA is a copy of a portion of your DNA that encodes a protein that the cell needs to function.
Well, the lipid nanoparticles have been essential for RNA therapeutics. RNA falls apart very rapidly. It’s susceptible to a hydrolytic cleavage in water. Put it into water, it doesn’t last very long. It also is susceptible to enzymes called nucleases, that break it down. These nucleases are everywhere in our environment, they’re on our skin, they’re in our body. So RNA is very fragile. It’s made to fall apart. It’s only supposed to be expressed in cells for a short period of time. It provides enough information for the cell to generate that protein that it needs at that particular point in time. So how do we protect the RNA? We put it into these lipid nanoparticles, which are a little bit like oil bubbles. Those oil bubbles protect the RNA from being broken down and they also deliver the RNA to the cell. The lipid nanoparticles can adhere to the cell, they get absorbed by the cell, they deliver the message RNA into the cytoplasm of the cell where that RNA can now be translated into a protein.
So how can we leverage mRNA technology to protect us against infectious disease? Well, message RNA is a bit like biological software. We can rapidly generate the antigen that’s desired, so if you’re making a vaccine, you need to understand a little bit about that infectious organism, need to understand the protein of that virus, for example, or parasite, or pathogen. And you need to understand what is going to trigger an immune response. Once you know what that protein is, you can design an RNA that encodes that protein, and inject that RNA into the skin, or into the muscle where it’s taken up by dendritic cells, other white blood cells, and you get an immune response now to that protein that was encoded by the RNA. So, because the RNA can be made very rapidly, the sequence can be generated very quickly you can respond to pandemics. So the first RNA vaccine against SARS-CoV-2 was generated within about five days, and in clinical trials within a few months so, the rapidity by which we can generate RNA allows us to respond very rapidly to pandemics.
You’ve been listening to Innovations in Medicine on ReachMD, sponsored by Moderna. To access this episode and others from this series, visit ReachMD.com/Innovations in Medicine, where you can Be Part of the Knowledge. Thanks for listening.