Iโm not concerned about the actual baby making part โ we can figure that out with practice. The part thatโs tricky is the fine-tuned and carefully orchestrated process of human development, particularly in the brain. Cells inย microgravityย donโtย growย exactly like cells on Earth, and a whole bunch of them in a developing babyโs brain may not grow exactly the same either.
Thankfully, thereโs a researcher for that.ย UC San Diego scientist Alysson Muotriย isย usingย blossoming clumps of brain cells called โbrain organoidsโ to understand how neurons proliferate, form synapses, and communicate โ but in space.

Inย late July, Muotri and his team sent a bunch of organoids to the International Space Station. Previous research has documented the proliferation ofย HeLA cells,ย cancer cells,ย bone cellsย and more, but there is limited information about the gravity-free growth of early brain cells, known as neural progenitor cells, or brain ย organoids. Suchย organoidsย have proven to be a useful model for understanding brain development, so understanding how they develop in the microgravity of space could demonstrate the ways in which human brain development might be affected if we ever become a space-faring society.
Muotri has long been intrigued by research in space, especially theย NASA twins study. A while ago, he half-seriously talked about the idea of doing his own biology space study with one of his collaborators, but nothing quite came of it. He dreamed of sending organoids to space, but didnโt know if it was possible. Once he met an engineer who convinced him it was feasible to actually build a device to keep organoids alive in space, he decided it was time for takeoff.
Still, he had some trouble selling others, particularly granting ย organizations, on the idea. Heโs funding the project out of his own salary savings and gifts to the lab, with the hope that his first wave ย of findings will draw attention to his work and convince funding agencies that his research is valuable.
Backed by his own money, the first task was figuring out how to keep the organoids healthyย at the International Space Station.
Even on Earth, the organoids require a lot of care to ensure that they are at the proper temperature and growing conditions. For one, theyโre kept in a shaker so that they are constantly suspended in a solution, without anchoring down to anything (though that wonโt be a problem in microgravity). But like living cells in a body, ย ย organoids require nutrients, and they also spit out waste. To support these processes, their solutions need to be changed, and the temperature and pH needs to be carefully maintained, like fish in a tank. Organoids require a lot of babysitting, and Muotri simply canโt expect the astronauts to spend as much time caring for his cells as he and his students do back on Earth.

So, he collaborated withย an engineering team from Kentucky that specializes in sending biological material into space.ย They developed a shiny red box called theย Space Tango CubeLab.
Space Tango may sound like aย bad 80โs science fiction filmย starringย Antonio Banderas, butย itโs actually the name of the company, and the productsย they make areย soย much cooler than โ80s sci-fi. The โCubeLabโ essentially functions like a fully automated, climate-controlled mini-laboratory: it can change the media for the cells, monitor their growth, and send ย the data back to Earth. The astronauts just need to plug it in.
For this very first mission with the organoids, Muotri wants to see how the cells grow and proliferate. Based onย previous research,ย he ย predicts that โThe progenitor cells will proliferate faster and will ย probably generate a bigger organoid.โ Although a bigger brain sounds better, this might actually be a problem: if the brain and surrounding skull are too big, it might prevent birth through the birth canal. Itโs still speculation, but itโs entirely possible that โmaybe humans cannot have natural deliveries in space.โ
The other issue with faster brain development is that large brain volumes have been implicated in the development of autism spectrum disorder. In fact, having a larger brain circumference is one of the mostย robust biomarkers of autism. โWe donโt fully understand how cell proliferation may later in life lead to intellectual problems or cognitive disability, so this gives us a model to understand that,โ Muotri hopes.
At the moment, we donโt know much about the cellular mechanisms that microgravity could directly impact. Using genome sequencing and techniques to detectย epigenetic signatures, Muotriโs team will look to see if the genomes of the ย organoids have changed. โThere is definitely an epigenetic signature that changes neurons in space,โ Muotri insists, โthatโs what we want to figure out.โ
Of course, organoids canโt capture brain developmentย in uteroย in its full complexity. However, this study could point us to important considerations before we pack our space bags. For example,ย itโsย possible that people with certain genetic backgrounds are less susceptible to the (lack of) pressures of microgravity and might fare better in space. However far-fetched, the social implications are staggering. If it turns out that some genetic backgrounds are better adapted to have babies in space, would this dictate who could become space-faring?
Lastly, Muotri would like to compare organoids generated from cells of healthyย patients to those from people with Alzheimerโs or Parkinsonโs disease. In 2011, a lab down the hall from Muotriโs at UC San Diego showed thatย neurons derived from schizophrenic patientsย were ย different than those derived from neurotypical patients. However, similar in-the-dish research on diseases of the aging brain have been limited. Organoids closelyย resembleย young neural tissue, and it is a lot of work to keep them alive until they start to look like an aging brain. When Muotriย compared neurotypical and Alzheimerโs organoids in Earthโs gravity, they were indistinguishable.ย However,ย this might not be true in space: โMaybe in the microgravity of space the organoids will age faster, and we could reveal their [Alzheimerโs] phenotypes.โ

Muotri would also like to send the organoids up with even more sensors, including recording arrays that can actually measure the electrical activity of the organoids while theyโre in space. Such data could provide clues about the functionality of these brain clumps, in addition to their genetic and anatomical signatures.
Muotriโs energy and enthusiasm for the project is palpable. But he has one big concern: when the mini-brains were sent into space, there was a 24-hour black out period during launch preparation over which the Space Tango couldnโt send back data. Muotri confessed that this was his biggest worry for the mission. But, he still laughed heartily, โWe just have to hope that everything is going to be okay.โ
Ashley Juavinett, PhD is a neuroscientist, educator, and writer. She currently works as an Assistant Teaching Professor at UC San Diego, where she is developing novel approaches to teaching and mentoring folks in neuroscience. Follow her on Twitter @analog_ashley
A version of this article was originally published on Massive’s website as “There might be some problems when we try to make babies in space” and has been republished here with permission.ย























