You can listen and subscribe on Apple, Stitcher, and Spotify. And if you like what you hear, a five-star rating goes a long way toward helping us Track the Vax! Richard Kuhn: Traditionally, for viruses, we’ve either taken a virus and inactivated it, and used that as a vaccine, or we’ve taken a virus and made it less infectious — that is, it’s attentuated — and made that a vaccine; or we’ve expressed proteins that are on the surface of a virus and used those proteins as stimulants for your immune system. These would be purified proteins that would be injected. … The protein self-assembles into something that resembles the virus, but it doesn’t have any of the components that allow the virus to replicate. So those are the standard, traditional vaccines. … The technology that Moderna and Pfizer are pushing right now is one in which you use the coding sequence, the information that codes for the viral protein that you’re interested in. In the case of COVID-19, we’re interested in a surface protein that we call the spike glycoprotein — spike for short. This technology basically uses the genetic information that will make this spike protein when you put it into a cell. And that information is encoded in what we call messenger RNA — mRNA. That’s the vaccine, and it’s packaged in a lipid nanoparticle for delivery purposes. Serena Marshall: That’s a ton of information, and I want to unpack it a little. Let’s talk about the vaccines of days past, [in which we get] infected with a weakened version, an attenuated version, as you said. A lot of people think, Okay, so when I get this new COVID vaccine, am I going to be getting COVID? That’s not the case here. Richard Kuhn: That’s absolutely correct. First of all, there’s no infectious material being injected into an individual; you’re only making a single protein, but it’s the critical protein that your immune system will respond to. What will happen is, that lipid nanoparticle will be able to enter cells in your body after you’ve been vaccinated. And that RNA, the messenger RNA, will make a protein, just like all the proteins your cells normally make. The only difference being that once it gets made, … other cells are going to recognize it as foreign. And they’re going to mount a response against it. Serena Marshall: Why is it that this virus is able to have that protein and able to have that immune response? Richard Kuhn: Well, this technology has been around for a few years. In fact, Moderna developed the technology initially against Zika virus. … In the case of Zika virus, there was this massive expansion and infection of people in South and Central America, and everybody was very concerned, and then the virus died off. So Moderna had this technology but was never able to go to clinical trials because there was no Zika virus prevalent in the population. Serena Marshall: So when we hear that this is a brand-new technology that’s never been approved before, that’s all true. But it’s not new research; it actually, as you said, goes back to Zika. But also, [for] decades before they’ve been looking into this. Richard Kuhn: The COVID-19 pandemic is the perfect situation for producing a messenger RNA vaccine, because it’s very easy to produce in a large scale. Because it’s synthetic, you don’t have to grow anything in cells, which has been the traditional way that you produce vaccines. So it’s very easy, it’s very rapid. As soon as you have the genetic information of a virus or a pathogen, you can begin to develop a messenger RNA vaccine against it, which trims off years of very difficult work that we’ve previously had to do with the older vaccines.
