Tardigrades are microscopic eight-legged animals that have been known to survive extreme conditions. University of Wyoming researchers are now applying their research of tardigrade survival skills to vaccines. Wyoming Public Radio’s Sage Montana spoke to Boothby. They started by talking about what a tardigrade is.
Editor’s note: This story has been lightly edited for brevity and clarity.
TB: They're microscopic animals. But why we really love tardigrades is that they are extreme survivors. Despite being so small and microscopic, they're extremely robust. And they can survive a number of environmental stresses that we typically think of as being incompatible with life. So for example, tardigrades have been frozen down to a degree above absolute zero, that's the temperature at which all molecular motion stops. You can also heat some tardigrades up well past the boiling point of water. They can go for days or weeks with little or no oxygen. Many tardigrades can survive 1000s of times as much radiation as you or I could survive. They can do this amazing trick where they survive being dried out, so they lose essentially all the water inside their bodies and cells. If people have heard of tardigrades before, they've probably heard of them because they're actually the only animal we know of that can survive in the vacuum of outer space. They've been sent up into outer space, out in the vacuum, exposed to cosmic radiation. And when they were recovered back on Earth, they seemingly didn't care. They were able to reproduce and their offspring were able to reproduce. And to this day, there's a lab in Sweden that's propagating the offspring of those space flown animals.
SM: When you are doing your experiments, is there a typical procedure you do with the tardigrades?
TB: With the tardigrades themselves, a lot of the work we do is taking those animals and exposing them to different stresses. Then using some sort of more sophisticated methods, like next generation sequencing, [we] look at which genes are being turned on and off in the tardigrades when they're stressed. So for example, we can dry the animals out [and] look at which genes are being used during that drying process. Then we can do the same thing, but let's say freezing the animals to see which genes are being turned on when the animals get frozen. And then we can compare and contrast and say, ‘Okay, this looks like these genes are the tricks, the things tardigrades are doing to survive drying versus freezing.’ That kind of gives us some insights into how they're surviving this process. From there, we have a whole bunch of different approaches and techniques that we use, including using biochemistry, to study their proteins and the products that they make. Or using genetic engineering to take a tardigrade gene and put it into a human cell line that we're growing in the lab, does that make the human cells now more resistant to freezing or to dry[ing]?
SM: I read that one of the applications of your research is medicines and vaccines. How is your research of tardigrades applied to medications and vaccines?
TB: A lot of vaccines and other pharmaceuticals, while they're very effective, they have a major drawback. And that is they're also very sensitive. Meaning if we just leave them out, like on a desk or on a counter, they'll break down very rapidly. How we currently get around that is using what's called the cold chain. That's basically a system of refrigerators and freezers that keeps vaccines and other pharmaceuticals cold all the time to help maintain their efficacy. Now the idea that we have is, when a tardigrade experiences environmental stress, let's say when they're drying out, they've come up with ways to protect all the things inside their bodies and cells, like proteins, and nucleic acids, which many vaccines are made of proteins or nucleic acids. So if tardigrades have come up with these tricks to stabilize those biological components, during extreme stress, our thought is that we can apply those same tricks to vaccines or pharmaceuticals, and be able to stabilize those, even just at room temperature, or even at elevated temperatures in more harsh conditions. This would mean that now we wouldn't be reliant on this cold chain to keep pharmaceuticals stabilized. That would open up so many new avenues for getting medicine to people in remote or developing parts of the world, where you may not have access to stable electricity, refrigerators or freezers or other means of keeping pharmaceuticals stabilized.
SM: In theory, would that be able to be applied to any type of medication?
TB: Some of the tardigrade proteins that we're working with now that we found make tardigrades very robust and hardy, they seem to do very well at protecting other proteins. So a lot of vaccines right now, for example, are protein based. A lot of other biologic pharmaceuticals are also protein based. So we think that these tardigrades have the ability to protect a very wide range of different proteins. We've seen that they do have some efficacy at protecting nucleic acids. So this would be sort of applicable to mRNA based vaccines, like the Pfizer vaccine for COVID. I think what's really exciting is we're really just scraping the tip of the iceberg with tardigrades, and there's so much more to learn. They may have proteins that are particularly tuned to protecting nucleic acids or membranes. We could even apply this technology beyond just simple pharmaceuticals, but even apply it to things like stem cells in cell based therapies.
SM: I know research is really unpredictable. But I was wondering, is there any idea of a timeline?
TB: I think with our research and research of others, there's been pretty good proof of principle done. I think where the real time crunch is going to come is in getting through FDA approvals. We can't just start formulating these tardigrade proteins with existing vaccines or other pharmaceuticals. They need to go through safety trials to make sure that they don't induce an immune response, so they're not toxic. And that's work that we have ongoing here at the university now. We haven't started formal FDA trials, but we've started studies looking into toxicity and immunogenicity of these proteins, which will just give us good preliminary data going into those trials.
