Stem cells are a critical tool in the scientist’s toolbox. Stem cell therapies have been developed for a range of applications, from growing new heart muscle cells and replacing those damaged during a heart attack, to speeding recovery for injured athletes. But one of the biggest challenges to working with stem cells -- and expanding their clinical applicability -- is controlling when they differentiate.Complete cessation of differentiation is bad, of course -- cells that don’t differentiate into bone cells to create new bone mass aren’t very useful, for example. Yet identifying factors that researchers could leverage to better control differentiation may prove critical for designing better stem cell therapies for osteoporosis, wound and muscle healing, and heart muscle repair and regeneration.Such capability already exists, but sadly, the vast majority of researchers and organizations that could use it the most -- such as biopharma companies -- aren’t aware that it’s closer than they might think: they just need to take a trip to space.
Research has revealed that in microgravity, muscle cells atrophy, immune cell structure and activation are impaired, and, critical to stem cell research, embryonic stem cells do not differentiate and instead maintain a status of “stemness” due to upregulation of a cell cycle inhibitor called P21. This phenomenon was first reported by Elizabeth Blaber and Eduardo Almeida of the NASA Ames Research Center, who are two of just a handful of researchers worldwide focusing on stem cell differentiation in microgravity.Their results are tantalizing, says Dr. Carl Carruthers, microgravity researcher and Chief Scientist at NanoRacks, a Houston-based company focused on building the future of science in space. By helping unravel the molecular processes involved in cell differentiation, Blaber and Almeida are part of an elite few identifying factors that not only could help support human health and longevity in microgravity (think extended stays on the International Space Station or life on Mars), but also improve stem cell therapies right here on Earth.
Induced Pluripotent Stem Cell-Derived Cardiomyocytes (Cellular Dynamics) on magnetic carrier (GEM) beads. Image source: Eduardo Almeida
So, why is it that the results of stem cell research in microgravity are relatively unknown? Why is no one capitalizing on a veritable goldmine? According to Carruthers, it comes down to two major issues: science results from microgravity research are still too slow, and outside of NASA, investment dollars for research in microgravity are nearly non-existent.
To most scientists, setting up a cell growth experiment in, say, six microplates, and then performing RT-PCR to assess gene expression, or extracting DNA for sequencing, is all in a normal days’ work. But as the old adage goes, “You don’t know what you’ve got until it’s gone.”Those researchers, like Carruthers, who have tried to do scientific experiments in microgravity realize that something that most researchers on the ground don’t even think twice about is sorely lacking in space: automation. From liquid handling robots to high-capacity plate readers, automation instruments have significantly increased both the pace and volume of science done in laboratories across the world. With such key tools lacking for microgravity research, the International Space Station (ISS) is more like a time capsule: the pace of experimentation is like doing science in a 1970s Earth lab.This is in large part due to the Astronauts’ busy schedules, and the sheer volume of different ideas needing a flight to the ISS — there are a lot of great ideas, but sometimes those end up being one-offs. It’s hard to make initial investments in the automated lab equipment scientists would normally expect in an Earth-based lab.Because of this, most scientific experiments done in microgravity have been subjected to custom-made, never-to-be-used-again equipment run by ISS crewmembers. Even the revolutionary stem cell work done by Almeida and Blaber nearly ten years ago was performed using retired hardware. “That hardware doesn’t fly anymore, it was Shuttle unique,” says Almeida, who has since helped NASA developed a new cell culture system to get payloads back up into space. “It took us almost a decade after the Shuttle to get PIs flying on the Bioculture System again,” he says.
Shuttle-era retired cell culture unit CCU after the STS-131 flight that carried Eduardo Almeida’s stem cell experiment. The samples are in this box as the hardware is being opened immediately after the Shuttle landing. Image source: Eduardo Almeida.
While recent years have brought more powerful equipment to the ISS, such as NASA’s improved Bioculture System, an Oxford Nanopore sequencer, and NanoRacks’ cube-sat-based NanoLabs and microgravity-optimized reactor microplates, activities such as pipetting are still done by hand -- a tedious, time-consuming process for crewmembers whose time is carefully scheduled and divided across various tasks.“A lot of it is very basic,” says Almeida. “A cell biologist would look at it and twist his or her nose. It is not ideal for experimentation. There are a lot of constraints to doing experiments in space, things that we take for granted, that are routine on Earth …. just to get the logistics and all of the hardware to work is very difficult -- so progress is slow -- but despite that we forge ahead with doing cell biology in space.”NanoRacks has a lot of ideas for how to change this reality -- and it all boils down to automation. Carruthers points to organizations such as the DAMP Lab that provide infrastructure for researchers to send in samples, pick an assay online through a web-based system, monitor the experiment from their laptop, and then receive the samples back when the experiment is over. Hands-off infrastructure such as this is becoming more and more common -- and thus cheaper -- in labs on the ground. “I would love to see that kind of automation on the space station,” Carruthers says, and this is exactly the direction in which NanoRacks plans to push the development of the ISS commercial labs.
Such a scenario is likely to be made reality in large part through robots, which have significantly increased throughput for scientific experiments: a large portion of the DAMP Lab process relies on the Opentrons OT-2 robot, for example. Yet robots aren’t perfect, and it will be a challenge to figure out how to use them on the ISS or other space labs.“There’s a learning curve -- nobody knows if fluid handling robots will even work efficiently on the space station,” says Carruthers, “or what adaptations we are going to have to give the robots, if any, to get them to work accurately in microgravity.”But based on the relative ease with which he sees crewmembers pipetting liquids in microgravity by hand, Carruthers doesn’t think optimizing the equipment and getting it to work in microgravity is an insurmountable issue. In fact, NanoRacks has already teamed up with Olis Robotics (previously known as BlueHaptic), a company that developed telerobotic operating software for undersea drones used around oil rigs. Looking to make the transition into the space flight market, Olis has been working closely with NanoRacks to figure out how to apply their software to the equipment and systems NanoRacks is developing for the ISS and also for their own, next-generation commercial space lab.
In future microgravity research labs, experiments may be run telerobotically from command centers on the ground, with data sent back to researchers real time. Image source: NanoRacks
According to Adrian Mangiuca, NanoRacks Commerce Director, their goal is to use telerobotic operation to “remove the cost of the astronaut from the equation and be able to operate payloads in low Earth orbit from command centers.” One of the biggest ways to cut human costs is to use telerobotic operation to handle transition points, such as when plates are moved out of liquid handlers and onto plate readers. It was this vision -- telerobotic operation taking over research in microgravity -- that was one focus of NanoRacks’ LEO Commercialization study, which NanoRacks delivered to NASA last December.
The LEO Commercialization study, or LEOCOM, was a four month study on what the future of the commercial low-Earth orbit market looks like on the ISS and beyond. For this study, NanoRacks engaged a team of 13 partners (including Olis Robotics) -- unprecedented in their industry -- to propose Outpost, an “in-orbit commercial space station habitat development enabling cost-effective and sustainable U.S. presence in low-Earth orbit.”“We needed all these partners because they represented the full ecosystem of services that we would imagine requiring to have a successful market on a commercially broad, commercially procured platform in low-Earth orbit,” says Mangiuca, principal investigator of the study. “ represented hardware suppliers, service providers, and commercial users. our focus was on what kind of markets we see from these platforms right now and what they need to be commercially viable. Automation ... factored very heavily into our considerations.”A critical recommendation from LEOCOM was the necessity for private funding in the sector. Most research in space today is funded by NASA. That is a positive thing in and of itself, but those funds can’t possibly address all of the needs to truly launch space science. Instead, funding from sectors that could stand to benefit from research done in microgravity -- such as the biopharmaceutical sector -- will be critical to moving microgravity research from 1970s-era laboratory to fully automated, state-of-the-art facilities.
One of the major issues preventing private funding is that people just aren’t aware of the capabilities that already exist. They don’t know about the truly impressive research that’s been done using clunky, slow systems -- research that could be capitalized on and that could drive healthcare forward, such as Blaber’s stem cell research.It is furthermore difficult for investors and companies to understand the business model. Unlike rocket launchers to facilitate payload delivery, the ROI for funding automation in space isn’t as obvious. “Science isn’t as intuitive as engineering,” says Carruthers, which is why “PowerPoint rockets,” as he calls them, are easy to defend and get funding for in a pinch -- especially in a landscape dominated by the success of SpaceX and the promise of Blue Origin.
The microgravity experienced by crew members on the ISS leads to loss of bone and muscle mass. Research on preventive or protective drugs could not only help ISS crew members, but also people with osteoporosis or other musculoskeletal conditions right here on Earth. Image credit: NASA (public domain).
Nevertheless, some major biopharma players have caught on. Paul Reichert, Associate Principal Scientist of Structural Chemistry at Merck, has been crystalizing proteins in microgravity for Merck since 1993. Because protein crystals grown in microgravity tend to grow bigger and purer, they can be used to figure out how to improve the storage of structurally-fragile medicines and to improve drug delivery. In fact, Merck’s drug Keytruda was optimized in microgravity. Drug companies Novartis and Eli Lilly have also invested in microgravity research, and Amgen’s osteoporosis drug, Prolia, was tested in mice on the Space Shuttle prior to FDA approval.More private investment like that from Merck, Novartis, Eli Lilly, and Amgen will be critical to help NanoRacks and their commercial partners automate space science. When that happens, we will witness an exciting transformation in microgravity research, and therefore, in human healthcare -- one that will be felt all the way down to our bones.