Planetary Radio: Space Exploration, Astronomy and Science - Microbes in Orbit: Cheryl Nickerson’s Revealing Biomedical Research

Episode Date: April 8, 2014

You may have heard that the sometimes deadly Salmonella bacterium becomes stronger in microgravity. Cheryl Nickerson tell us about this and other results her team has conducted in low Earth orbit.Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Music Music Music Benefiting from Biomedical Experiments in Space, this week on Planetary Radio. Music Music

Welcome to the travel show that takes you to the final frontier. I'm Matt Kaplan of the Planetary Society. Cheryl Nickerson is preparing to send her seventh experiment into low Earth orbit. Her enthusiasm for this promising research is contagious, as you'll hear in minutes. Bill Nye finds it hard to believe that the spacecraft that has confirmed yet another ocean in our solar system could be in budget jeopardy.

And Bruce Betts tells us to look up at Mars in this week's What's Up. Emily Lochte-Wallace says, no, look down on the red planet. Emily, this new image, looking down on Curiosity from that HiRISE camera, kind of leaves me speechless. So please tell us what we're looking at. Well, it really never gets old to see the hardware that human hands have built actually sitting on the surface of another planet. And we routinely get that now with HiRISE, the camera on Mars Reconnaissance Orbiter in orbit at Mars. HiRISE can take these images with amazing detail down to 25 centimeters a pixel. And because our favorite nuclear-powered rover is two meters long,

that's plenty of pixels that Mars Reconnaissance Orbiter can get on Curiosity. long, that's plenty of pixels that Mars Reconnaissance Orbiter can get on Curiosity. And this latest photo was taken right after the rover had crossed a sand dune called Dingo Gap. The tracks that the rover left in the somewhat sandy soil all around this area are just wonderful to look at. You can tell it's exquisitely detailed. You can easily separate the two tracks. You can see what looks like little donuts. It's not the rover burning donuts turning around in a circle. It's what happens when you have a rover that turns in place with kind of tank-like turning. It makes a circle in the soil. And you can just follow the rover's path all across Mars in these pictures.

It's absolutely incredible to see. It's kind of like a Martian connect the dots. It's just incredible. What is this about dune monitoring, which is, I guess, something that MRO is up to? Well, yes. So Mars Reconnaissance Orbiter has been in orbit for a long time. The high-rise camera, it takes such small images that cover a very small area of Mars that, you know, most of the time they don't like to image things more than once because they'd rather get more coverage. But there are certain things on Mars that change over time. And when you expect things to change over time, you do want

repeat imaging. One of the things that does change, which was discovered in Mars Reconnaissance Orbiter images, is the sand dunes. Sand dunes can shift over time. Sand dunes also have ripples on their tops that migrate up and down the dunes over time. And there is a sea of sand dunes inside Gale Crater that Curiosity is eventually going to have to wend its way through. And so they're taking repeated high-rise images to watch the progress of the sand dunes and the sand ripples over time. And it just so happens that they can take those pictures in a position that allows them to image Curiosity in its tracks as well. So we're going to be seeing lots of pictures of Curiosity and of basaltic sand dunes over time inside Gale Crater.

I highly recommend taking a look at this. It's an April 3rd entry in Emily's blog at planetary.org. Lots of other good stuff there. If you go back a few days, you can read about the latest on the lakes on Titan. Emily, thanks very much as always. Thank you, Matt. She's our senior editor, the planetary evangelist for the Planetary Society, and a contributing editor to Sky and Telescope magazine. Bill Nye is next.

A new ocean discovered in our solar system, a new world with water under the ice, but it's the implications related to this, the Earthbound implications that I think you want to talk about. That's right. You know, all the money spent in space is spent on earth, Matt. But this Cassini spacecraft launched in the 20th century is still making discoveries on other worlds. And people are talking about curtailing the funding for it. This would be a space-based pun. Are you high? No. In other words, this thing is an extraordinary value, and it's an asset that's irreplaceable. There's a spacecraft orbiting Saturn, observing oceans under the ice on Enceladus. That is crazy.

And yet it's still going on here in 2014, and people talk about cutting the funding. They're just going down line items, I guess, with a fountain or a Sharpie and trying to put lines through stuff. It's just thoughtless. Furthermore, if you want to keep the U.S. in the game economically, you have to invest in space. And the most economical, the best bang for your buck in space is planetary science. Now, Matt, I sound like a broken record. I say this every week, but it's an important record. No other space agency can put a spacecraft in orbit around Saturn for 20 years,

more than 15 years, and let alone send back information 15 years later that's still, if I may pun intended, earth-shaking. Let's go world-shaking. That we have federal employees, representatives of the voters and taxpayers in the U.S., and really representing space enthusiasts or citizens around the world. It's really striking. This is irreplaceable, and it's only one example. There's a mission on the way to Jupiter.

We've got a mission at Mercury. Is there ice in the craters on the moon? This is where we solve problems that have never on the moon. This is where we solve problems that have never been solved before. This is where we innovate. This is what changes, if I may, the worlds. That's a recurring theme, Bill, but an important one. Thank you very much. Thank you, Matt. Thank you. He's the CEO of the Planetary Society, Bill Nye the Science Guy. Let's talk about science a little closer to home on the International Space Station. There are those, and some of them are respected scientists,

who insist that no real science will ever be done on the International Space Station. Certainly nothing that could benefit the billions of us down here. Cheryl Nickerson begs to differ, and she's not alone. Cheryl is a professor in the School of Life Sciences at Arizona State University. Her lab is in the Center for Infectious Diseases and Vaccinology at the school's Biodesign Institute. This winner of NASA's Exceptional Scientific Achievement Medal has testified before Congress about the enormous promise of microgravity for biomedical research.

And she's very persuasive. She talks fast, she drives fast at the racetrack, and she lives to accelerate our battle against the pathogens that want to kill us. You may have heard about her work with Salmonella, a sometimes deadly bug that somehow becomes more virulent in zero-g. Cheryl, welcome to Planetary Radio. It's great to be able to catch you in person here at the Space Tech Expo. Thank you for having me. I'm delighted to be here. So I've already mentioned your salmonella results, which got a fair amount

of press. But I really wonder if that headline told the whole story. Well, it depends on which headline you're talking about. If it was the sensationalized headline, that's not the story. Some media groups tended to sensationalize the research and think that there was something abnormal about the strain when it returned, and there wasn't. There was nothing permanently changed about the strain. The beauty and the real translational value of the research that we did on the shuttle while it was docked to the ISS is to understand how the leading cause of bacterial foodborne illness in the United States and a leading cause of death worldwide changes, transiently changes its responses when you greatly reduce the force of gravity under which it's cultured.

This may sound a little far-fetched at the moment, but I'm going to tell you, understanding how pathogens like salmonella respond to culture in the microgravity environment of spaceflight is not just important to mitigating infectious disease risk for the astronauts, because we certainly care about that. That's one of our goals. They're immunocompromised when they fly. And our research has shown that spaceflight increases the virulence. That's the disease-causing potential of Salmonella. So that's never a good combination when you're immunocompromised and you could encounter a pathogen that's more robust in its ability to cause disease.

But what was really intriguing to us, and this is what translates back down to the general public on Earth, is that while salmonella was altered in its ability to cause disease during space flight, it was increased in its virulence. None of the underlying genes which were responsible for causing that change were turned on and off in a manner that we would predict as when we see when we grow the organism here in the laboratory, conventionally in the laboratory. This is fascinating. The change in the behavior of this organism was not something that happened in space.

It's not as if it was a mutation or something, that these are just behaviors that are a lot easier to see in microgravity. When we culture cells, whether they're bacterial pathogen cells like salmonella, or whether they're human cells in our laboratories on Earth conventionally, we've learned a tremendous amount about how cells behave normally or transition to disease. Of course we have. But the force of gravity can mask some of these key responses we're looking to find that actually these cells are making down here, but we can't physically observe them. So when we culture cells in flight, these secrets kind of become unveiled. And we can learn those secrets.

So we use the spaceflight platform to discover. We come back down here, bring those experiments back down to Earth, and we work to recapitulate them as much as possible. There's no true way to recapitulate every aspect of how a cell responds to microgravity because there's no microgravity on Earth. But the beauty of this is, and I alluded to this previously, cells experience an environment that mimics aspects of microgravity in our bodies. It's not microgravity, but if you think about it, when you call culture cells in liquid, in a liquid medium culture, their growth media, in spaceflight, they're in a very what we call a low fluid force, a low fluid shear force.

You can imagine. It's kind of like when you train astronauts at the Johnson Space Center in this big buoyancy. Neutral buoyancy. Yeah, neutral buoyancy. And they're kind of like in slow motion in terms of the fluid flowing over them. We call that force of fluid moving over the surface of a cell fluid shear, shear spelled with an A, S-H-E-A-R. And you might say, well, why is that important?

That's important because that's where the translation comes in, back down here on Earth. So by flying salmonella in microgravity, we learned new ways about how it's causing disease in the body. And it's probably turning on and off those same genes to mediate its disease-causing potential in the body. turning on and off those same genes to mediate its disease-causing potential in the body, but we're missing those genes because we're not culturing them under the conditions we can up there, and thus gravity is masking them. So when salmonella and other pathogens infect our tissues and our body, there are certain areas of low fluid shear force in the body,

in the intestinal tract, in the respiratory tract, in the urogenital tract, and these are the most common sites of microbial infection. But when we traditionally culture pathogens, we don't culture them under those conditions. We either shake them very, very, very, very, very rapidly in a liquid flask in the laboratory under forces that they would never encounter in the body, or we culture them statically where the force of gravity pulls them to the ground. You also don't really encounter those conditions in the human body per se. But if you culture pathogens under this low fluid shear force that's similar to what they encounter in the body, then we are able to mimic some of the changes we see in microgravity. And we do our,

what I like to say, our ground-based microgravity analog culturing using what else? Special NASA-designed culture chambers that astronauts and engineers designed to allow us scientists here down on Terra Firma to culture ourselves under conditions which mimic them being cultured in space flight. Are these the chambers that you also use to make sure these are controlled experiments that are underway hundreds of miles overhead? Well, it's actually totally different hardware that we use in flight. So we don't use these rotating bioreactor culture chambers in flight. We have to use a different hardware because that flight hardware is no longer certified.

That hardware is not certified to fly anymore. I see. But this special rotating chamber that we use does two things. It mimics that low fluid shear that these cells encounter in spaceflight culture, but at the same time, it's mimicking, and we worked with engineers to definitively show this, it's also mimicking levels of fluid shear that these pathogens encounter in the body. There's a double win for us in this because those low levels of fluid shear are important for your tissues functioning the way they're supposed to function because if you change that fluid shear you deprive them of that fluid shear your tissues start not functioning

normally and disease can set in so not only is that level of fluid shear important for your tissues and by the way we've used that on the other half of my laboratory which is bioengineering we bioengineer three-dimensional cell-based models of human tissues outside the body and we use them as human surrogates to understand how your cells and tissues respond to infection, or we use them in drug and therapeutic development, and we're also now working with transplantation surgeons to potentially, in the future, use these for regenerative medicine. So that's the other half of the lab. The side we're talking about now is using these bioreactors to mimic aspects of what we see bacterial pathogens

exhibit when we culture them in flight. We can mimic a number of the changes and responses we see salmonella and other pathogens have in space flight. And you might say, well, then why don't you just do everything in the bioreactor? But you can't because it's a model and no model is perfect. So we probably miss about 25 to 30 percent of those unique responses in microgravity by using the bioreactor. But the beauty of using the bioreactor is there's not a routine and consistent access to the spaceflight platform. My team has been very lucky. We've had six shuttle flight experiments. And our experiments continue on the International Space Station using SpaceX, which we're delighted to be able to pair with.

Even then, I've had my own laboratory for 15 years. You imagine running six experiments for 15 years worth of a laboratory and see how quickly you can advance a field. And you can't, but you can if you make the discoveries in true spaceflight or microgravity environment, bring them back down, mimic as many of those as you can, formulate the next discovery that you want, the next hypothesis you want to test in spaceflight, fly that next experiment, bring it back. So it's this iterative process of leveraging our spaceflight findings from the previous experiment, advancing the science on the ground, and then flying again for the next discovery.

What other basic functions of cellular life have you found are affected by microgravity? Well, we haven't yet because my laboratory and other laboratories have just are just beginning to touch the tip of this iceberg. So 99.99% of all of our discoveries with biological systems has come under unit gravity here on Earth. We have uncovered tremendous amounts of information about how cells respond and adapt to culture under conditions here on Earth. But we haven't been able to really use the microgravity platform that long to understand underlying cellular molecular mechanisms that are helping us to understand that we can't see down here how cells behave normally or transition to disease.

For example, my laboratory is using the platform to understand how microbial pathogens cause disease in our bodies. So we can actually translate that, and we already have flown a translational spaceflight experiment based on our previous flight experiments. It was a vaccine development initiative. So we really want to bring back this amazing discovery potential to benefit the general public who paid for the spaceflight platform, right? In addition to like vaccine development and infectious disease research, basically the leading causes of human morbidity and mortality, there are people who are flying spaceflight

experiments to address those. So in addition to infectious disease, you have cancer and other immunological disorders, bone and muscle wasting loss diseases, neurocognitive disorders, and aging, which many people would call this a disease. And they have found really incredibly compelling, novel ways that these systems are responding in spaceflight that we don't see down here, and yet we don't have answers for them down here. in space flight that we don't see down here, and yet we don't have answers for them down here. So why would you not invest in this novel, unique platform to help provide those answers? Because quite frankly, for every new drug to come to market, it's an average of $1 billion,

no matter what it's treating. And for the amount of time to get that market into the hands of the general public, 10 to 15 years. It's too long. So we need to use these innovative platforms to be able to advance the research and reduce the time to get it to patients and reduce the cost to get it to patients. And people say, well, it costs so much to do spaceflight research. And I would argue, do you know how much money we've spent trying to, and I don't even like to use the word cure, but come up with these novel solutions to diseases that are still leading causes of death and illness and suffering down here. Some of the biggest disappointments in the 21st century have been a lack of effective vaccines against pathogens which are a plague to mankind. So why would you not try another platform, an extreme environment

that can help us understand that process? Especially right now, I would think, when so many of those pathogens seem to be winning the race. You are spot on. So our challenge on this planet is to outpace infectious disease. That's Professor Cheryl Nickerson of Arizona State. She has more to tell us when Planetary Radio continues in a minute. Hey, hey, Bill Nye here, CEO of the Planetary Society, speaking to you from PlanetFest 2012, the celebration of the Mars Science Laboratory rover Curiosity landing on the surface of Mars.

This is taking us our next steps in following the water and the search for life to understand those two deep questions. Where did we come from, and are we alone? This is the most exciting thing that people do. And together, we can advocate for planetary science and, dare I say it, change the worlds. Your name carried to an asteroid. How cool is that? You, your family, your friends, your cat. We're inviting everyone to travel along on NASA's OSIRIS-REx mission to asteroid Bennu.

All the details are at planetary.org slash b-e-n-n-u. You can submit your name and then print your beautiful certificate. That's planetary.org slash Bennu. Planetary Society members, your name is already on the list. The Planetary Society, we're your place in space. Welcome back to Planetary Radio. I'm Matt Kaplan. I'd like to see someone try to tell Cheryl Nickerson that biomedical research on orbit is a waste of time. She'd hit them with tantalizing research results that may just scratch the surface of what is waiting to be learned in microgravity. Of course, I'd also like to see how they'd stand up to her passion for and belief in this work. The Arizona State professor and her team primarily conduct experiments up there on pathogens.

But she reminded me at the Space Tech Expo that not all bugs are bad. Far from it. Now, most microbes aren't pathogens, and most are probably, or a lot of them are very beneficial to us. Let's face it, we wouldn't have the Earth that we have now. We wouldn't even be sitting here talking, you and I, if it weren't for microbes. They've transformed our entire planet, our existence. We require them to survive. However, those pesky little pathogens are the second leading cause of death worldwide. They kill 35% of people globally every year.

They're the leading cause of death in young adults and children. In the U.S. alone and in developing countries, the cost would be staggering. But in the U.S. alone, we spend $120 billion of our economy every year is because people get sick. Now, usually they don't die from pathogens in our country, but you can't work. If you can't work, you impact the economy. And you're quite right to say we have to be very cognizant in the current time we live in. There's new and re-emerging pathogens, and those re-emerging pathogens often have multiple antimicrobial resistance. They're more difficult to treat. We have more immunocompromised individuals. The good news is we're living longer. The bad news is we're living longer.

And so, you know, you're immunocompromised as you get older. A lot of people are in different types of medical treatments, which compromises their immune system. And, you know, you're immunocompromised as you get older. A lot of people are in different types of medical treatments, which compromises their immune system. And, you know, unfortunately, we have to be aware in our current global climate of individuals who would inappropriately and intentionally misuse biological pathogens as agents of terrorism. that provides us insight in a ways to how to outpace these infectious disease agents and allows us to get to translational outcomes or has, I won't promise you get a translational outcome with spaceflight research, but I can't promise you that in my laboratory. Nobody can promise you that. What I can say is there is such tremendous potential for studying biological systems

in the microgravity environment to unlock their secrets as to how they're behaving normally or transitioning to disease, we would be foolish not to utilize this platform. The general public spent billions of dollars to build the most amazing engineering feat of all time, arguably, the International Space Station. And I don't even know how many of our viewers realize that it is the latest U.S. National Laboratory floating 220 miles above our heads right now. It's there. You must be excited about this new commitment by NASA to doing much more science now that the thing is fully built. I am incredibly excited by it, and I think everybody should be.

Look, science, while ISS was being built, was done on the fringes of ISS being built. Okay, you had to build the ISS first, and then science could then take more of a mainstream. You've got an international, a U.S. national laboratory up there on the ISS, and just having the United States designate that as the United States' 18th national laboratory really underscores the significance and importance that our country places on the value of this platform to give back these kinds of translational findings. And to make sure people understand, I mean, this basically puts the ISS at the level of Los Alamos or Lawrence Livermore, these kinds of facilities. Yes, that is number 18 in the U.S. National Laboratory.

And the U.S. National Laboratories were put in place in order to do research that could advance our quality of lives, and initially to support the war effort, but then they became transformed to advance our quality of life. And so we have to maximize its utility. I don't know if people really understand the value, how critically important the ISS National Lab is to us. First of all, it's built, it's got research equipment in it, and it's open for business. Now is the time to use it because trust me, our international colleagues understand this. And there's an ever increasing number of spacefaring nations that are putting money into microgravity research. NASA is putting money into this because the commercial spaceflight industry

needs the ISS to succeed and the ISS needs the commercial spaceflight industry to succeed if we're actually really going to be able to have a real meaningful use of the low-Earth orbit microgravity research platform for translational advances for human health and quality of life, which NASA wants the commercial groups to do, thus freeing NASA to go do the inspirational human discovery into deeper space. Right, right. One cannot succeed without the other. It's not an us or them.

It's not commercial spaceflight alone, and it's not the ISS alone. You have to have both of those entities working side by side together collectively to make this work. Trust me, if we don't utilize this platform, we have one shot. In our lifetimes, we're not going to see anything of this magnitude again. Other countries are getting it. They're investing a lot of money in this platform. And with commercial spaceflight ready to roll, we cannot miss this opportunity because if we don't capitalize on this opportunity,

I think the U.S. is going to find themselves sitting on the porch and watching the rest of the world lead the effort. And it should be a worldwide collaborative effort. Everyone should get to have a place at the table. And I would like to see the U.S. keep their rightful place. I agree with you that this message is not getting out the way that it should. Do you still hear from people who say, oh, the ISS, it's just a national point of pride, it's a way for us to look like we're participating in the global community,

who don't get it, that really there are results, not just yours, but colleagues that are seeing tremendous potential. Absolutely. I will add to that, I think that skepticism is always good. I think that it's very important to be skeptical, to be critical. Otherwise, you'll believe anything that comes along. Okay. And as scientists, we're used to tearing it down, breaking it apart and throwing it against the wall and it better stick.

That's how the game works. So good. Bring it. You should bring it. However, you know, as well as I do, that paradigm changing science is almost always met with pushback and resistance because we're humans and scientists are no different. And there's a certain comfort zone we don't like to get out of. But when you think about paradigm changing science science, this is usually high-risk science, but not high-risk science without a payback. This is high-risk science with a potential, a real serious potential to pay back dividends into the general public. I mean, if you think about it, in the 20s, when the Secretary of War at the time heard that someone had proposed that we would be – airplanes would be able to sink battleships by dropping bombs on them. And he immediately came out and he said, my God, that idea is so ridiculous that I'd be willing to stand on the deck of a battleship while that nitwit tried to hit it from above. But you continue – I mean that's what happens usually when you're challenging paradigms.

And Lord Kelvin saying, I think we've discovered everything there is to discover. Absolutely. And when the computer was first built, why would any normal sane person in the general public want to use it? They took up the size of a wall. And what did they do? They added up numbers. Why would you want to do that? Okay.

So hearing no is a good thing. I want to ask you about that other side of your lab that you mentioned very briefly, the bioengineering side. I just recently did a show for a different program about bioprinting, 3D tissue structure growth. Say a little bit more about that because it sure seems like microgravity was made for this. Well, it was. The three-dimensional aspect of cell culture is really the wave of the future. It's actually the future's here. It's been proposed for several decades by the cancer world. Certainly, pioneering individuals like Mina Bissell have studied cancer biology in three

dimensions for a long time. The infectious disease world just was behind the curve and hadn't really thought so much about that. And it makes perfect sense because tissues in your body, organs in your body, function and are designed to function in a very three-dimensional architecture. They have to have that structure in order to function. If you tear down that 3D architecture and plate them in a laboratory in a flat plastic dish on impermeable surfaces, which is about 99% of the way that most people do cell culture, growing cells on flat dishes where the cells are plastered against that surface is not the way cells grow and thrive and differentiate and function in our body. Now, don't get me wrong. Again, the vast majority of our research has been done with flat two-dimensional cell cultures.

And we've learned a lot about all kinds of biological disorders, but we have missed so much because we haven't studied the tissue in its natural architecture. And when you grow and generate and establish three-dimensional models of different tissues, like my laboratory has done intestinal, lung, your genital, a brain, a liver, periodontal ligament. We've done a lot of the major different tissues in the body, and we've actually made some of them immunocompetent because we want them to function more like tissues in your body. And we use them as human surrogate models outside the body. We infect them with pathogens, and we find out that they're responding more like your body does or like an animal's body does when it's infected as compared to when you grow those cells on flat dishes where you have a 50-50 shot at best. We also have shown that they respond more to testing with drugs the way the patient's body responds to testing with drugs as compared to testing on a flat dish.

And as I mentioned, some of the models, and again, we're still in animal stages with this, but they're showing such promise for the potential, I stress again, for regenerative medicine and transplantation approaches. You know, people die on waiting lists for transplanting new organs. And even if they are fortunate enough to get that new organ, they have to be on immunosuppressive drugs for the rest of their life. And that takes a toll on the system too. What if, what if you could actually build that tissue functionally in situ outside of the body. And then when it's needed by a person, you could use their own stems. Actually, you would build that tissue with their stem cells too. We're doing that now.

And then they can't reject it because it's their cells. And now, I do want the viewers to know we're not there. We're not doing this now in human clinical trials. We're in animal tests. But this is the future. They're tantalizing signs of this. This is the future. And actually, some tissues have already been grown outside the body and implanted

in our functioning trachea, etc., bladder. Yes. So we're actually working with very talented groups of individuals on more complex tissues like lung. And that's one of the most complex tissues in the body to be able to functionally generate outside. But I'm very optimistic that in the future, I can't give you a timeline. I can't tell you two years. I can't tell you four years. But I'm very optimistic that we will be able to do that as a scientific community. And you're going in exactly the direction I was hoping, because as we were coming in, you were talking about how you're on deadline for getting more grants submitted.

Where do you hope to take your research, especially that portion of it that takes place up above our heads? Oh, my goodness. How long do we have for the interview? Not long enough. Well, good science generates more questions. If you've answered all the questions you can with your scientific research, then you didn't do very good research. So we have generated God knows how many additional directions we want to go.

We have just written five new grants for some of those directions for our space flight and our ground-based research. They range in areas as diverse as obviously infectious disease, tissue engineering, cancer, and oncology advances, as well as nanotechnology. They're ranging the gamut. You do need to keep your eye on the prize and focus and say, okay, once you continue to leverage your findings and you're continually advancing to the next step, you don't want to drop the ball there and just move on with something else. But we happen to be very, very fortunate. It's a team that does this. I don't do any of this alone. No scientist does. If I didn't have the amazing students and research technicians and postdocs and other incredibly talented researchers around the country and actually internationally,

that I get the privilege to collaborate with on a daily basis. And it's very multidisciplinary. So our expertise is microbial pathogenesis, infectious disease, and tissue engineering. But we work with physicists. We work with chemical engineers. We work with mechanical engineers. We work with mathematical modelers and computational biologists and vaccinologists and immunologists. It's just like flying a spaceflight experiment for the astronauts. It takes a team of people to get that crew ready and get them up there and just to get the craft ready to launch. And it's the same thing in science. It's a beauty to be able to work in these large collaborative teams to try and bring a new approach to solve some of the major challenges that we face daily on human health and quality of life.

And we continue to advance our goals of research. We have been able actually to show that a lot of bacterial pathogens actually respond using the same kind of master switch regulated that salmonella does in flight, which has implications for them doing the same thing in the body. We want to continue to unveil these secrets using the unique microgravity platform to understand how these little organisms that are too small for us to see with the naked eye are causing disease in our body. And likewise, with our tissue engineering to understand how our tissues are responding to them. We just want to make the world a little better when we leave than it was when we were here. Just briefly, what's the nature

of the SpaceX work? Is there another one of those coming up? Yes. So that is the seventh in our series of continuing our findings. And this will be the first experiment that's been done to infect an entire organism in real time in space flight and follow the kinetics of that disease over time while matching it with the gene expression changes. There is this tiny little worm called C. elegans. What it is is it's a human surrogate model for infectious disease, and one of our major expertises in my lab is enteric foodborne illnesses, hence working with salmonella. So the little worm that we work with called a nematode is basically a gastrointestinal

tract from one end to the other. And it is used to study how aspects of enteric disease happen in the body. Now, obviously, it has some differences in physiology from the human, but it's a very useful model. So this will be the first time that a living organism, and we've already previously infected human cells in flight, and we were the first to do that, but now we're taking it one step further,

and this will be the first study to infect a living organism in flight in terms of monitoring the infection in real time. It will be videoed and monitored from the very beginning to the very end, and while that real-time infection is ongoing, we will be fixing separate sets of the organisms so we can actually take a snapshot of their gene expression, how it's changing at that very point in time we're imaging them. So we can link the gene expression differences to the disease phenotypes that we're seeing. It actually doesn't happen that quickly.

It's a lot of analysis on the ground. And we fully envision that just as spaceflight has given us really novel insight in terms of how pathogens are causing disease in our body, we're going to be focusing our studies this time on the living host's response. It's cellular, it's molecular, it's immunological responses to the infection. You know, if I was one of those mission specialists, astronauts, who's going to be working with your experiment, basically your hands and eyes up there on the ISS, I'd be pretty proud. I'd be pretty excited. Well, thank you for that. That means a lot. And I will tell you that we are, it's just to say that we are like launched into orbit, to be able to work with the amazing crew members that we've gotten the chance to work with is unbelievably exciting for us.

It's a two-way street. As I said, it's a team. It's really exciting to us that the crew is equally excited to actually capitalize on the value of that scientific discovery. But at the end of the day, everybody wants the same thing. We want to bring some new advances to help us stay healthier down here. Some more benefit for humankind. Absolutely. I've got to let you get to your panel discussion here at the Space Tech Expo,

but I've got to ask you one more thing because I hear you enjoyed the movie Gravity. Oh, I did. A scientist on orbit. Would you trade places with Sandra Bullock's character? I mean, less the debris, the pesky shower of debris, of course. Yeah, I'd go up there in a heartbeat. I'd go up there in a heartbeat. I would love to do the experiments and be involved in contributing to research in microgravity.

I almost got the chance to do that in 2004, but I'm not ruling it out in the future. Good luck with that. Thank you. And thank you so much for joining us on the show. This has been great fun. It's a pleasure. Arizona State University biomedical researcher Cheryl Nickerson, back in a moment with Bruce. Time for What's Up on Planetary Radio. Bruce Betts, the director of projects for the Planetary Society, is on the Skype line and is ready to tell us about the night sky.

And we've got a big response to this week's contest. So stay tuned for that, too. Hi there. Hey, Matt. Happy birthday. You knew. I wasn't going to say anything. That's why it was my job to wait until we were recording.

He's right. We had a wonderful weekend, had a very nice family birthday party, and got a lot of space gifts. My brother James gave me an Estes rocket. My brother Stephen, he gave me a flight jacket with all the Apollo patches. I don't know when I'm going to wear it, but I'll find an opportunity. It's very warm. We will force you to wear it. Yeah, I'm sure I'm going to wear it, but I'll find an opportunity. It's very warm. We will force you to wear it. Yeah, I'm sure I'll have to now.

Next time we do this face-to-face, I'll wear it. But thank you. I appreciate that. So in honor of your birthday, it's here, Matt. It's here. It's Mars opposition. I'm taking the telescope out tonight. Well, on April 8th is opposition when Mars is on the opposite side of

Earth. And then on April 14th is actually when Mars is closest, which oddly are not quite the same because those pesky elliptical orbits make it on the opposite side of the Earth from the sun. Not quite at the same time, but all really good times to look at Mars in the sky. That's the real point. Check it out rising in the east around sunset, setting around sunrise, as planets will have want to do when they're at opposition. And it is about as bright as Sirius, brightest star in the sky, but looking reddish and nearby is bluish, much dimmer right now. Spica, the star Spica. Also, you got Jupiter in the early evening looking really bright high in the south. Saturn coming up in the east a couple hours after Mars.

Venus super bright in the pre-dawn east. I'm going to get the telescope out tonight. It's close enough and it's a nice clear sky here in Southern California. What else is going on up there? There is also a total lunar eclipse, and this is on April 15th. Now, really, if you're hanging out like we are in Western North America, it's the night of the 14th through the 15th of April. Greatest eclipse is at 745 UT, universal time, on April 15th, and it's eclipsing for a while before that and a while after that. This is visible and groovy throughout most of North America, South America, and Australia. Tough or non-existent in the rest of the world in terms of seeing it, because you'll be on the wrong side of the planet, but this time you and I are on the right side of the planet.

For once. That's all right. They'll get their turn. There are more. There are more coming in the next couple years. It'll be fun and glorious. But don't miss it. It was this week in 1961 that Yuri Gagarin

became the first human in space. And then 40 years later, 2001, Mars Odyssey launched, still working fabulously 13 years later. Yeah, let's hope it keeps it up for a while longer. And now I hear you've got something, someone. Here we go.

Hey, Bruce, this is Cheryl Nickerson from Arizona State University. It's time for a random space fact. And that's not the last of our celebrity random space fact introducers. We'll have somebody else fun for you next week. That's very fun. All right, here's your fact. There have been five or more active missions at Mars for the last 10 years. We've had at least five working at any given time for the last 10 years at Mars.

That makes me proud. It's pretty cool. And now we've got two more on their way. All right, we go on to the trivia contest. We asked you what major moon orbits Saturn at about the same distance that the moon orbits the Earth. How'd we do? I was not expecting much of a response to this one. And yet we got a big response, a surprisingly big response.

Nicholas Schmidt, I think he's a first-time winner, up in Lompoc, California, not too far north of us. He's the one of many who said it's the moon Dione. Is that correct? That is indeed, orbiting pretty much the same distance from Saturn as the moon from Earth. Well, like I said, we had tons of people who got it right, but it was random.org that picked Nicholas. And so, Nicholas, we're going to send a Planetary Radio t-shirt up your way. I was wearing one for my birthday, as a matter of fact. It's that great.

I wore one just yesterday. We're like practically twins. We are. People say it all the time. Randy Bottom. This is slightly obscure. If there were five of them, they'd be called the Dione quintuplets. Look it up, folks.

Really. I think it was from the 40s, the 1940s. Here's a complaint from Joe Murray, who also got the answer right, but he was also upset. Because you know how we talked last week. We said Leica could not be counted as an astronaut. We wanted spacecraft that were not designed to re-enter safely. He said, concerning prior quiz, first Pluto is demoted to minor planet status. Then you say Laika cannot be an astronaut. What's next? Sirius can't be the dog star? Oh, I don'tabbling. You're the one who brought it up.

Yeah, I know. We also got something from William Wilkerson in Pittsburgh, California. He said, if I get the answer correct and happen to win, I'd like to give a shout-out on Planetary Radio to my 20-month-old twins, Everett and Aurora, future astronomers and planetary scientists. But you didn't win, William, so I'm sorry. We can't do that for you. You are so mean. Take delight. What do you got for next time?

Alright. Who was the tallest astronaut to fly in space? And how tall was he? Or she? There may be more than one answer that ties, but give me someone who is about the tallest or the tallest astronaut to have flown in space. Go to planetary.org

slash radio contest. Get us your entry. Get it to us this time by Tuesday, April 15th. The 15th of April at 8 a.m. Pacific time. How about that? Alright, everybody, go out there, look up in the night sky, and think about siblings. Thank you, and good night.

Siblings who give you great space-related gifts. And other things, too. I've got three. One of them is not terribly space-related. Maybe it's a space... Never mind. He's Bruce Betts, the Director of Projects for the Planetary Society, who joins us every week here for What's Up.

Planetary Radio is produced by the Planetary Society in Pasadena, California, and is made possible by the brotherly and sisterly members of the Society. Clear skies.