Induced pluripotent stem cells (or iPSCs) are a type of stem cell that can develop into the three main groups of cells that make up the human body. They can be obtained from a person’s blood or skin, and their importance in research is enormous. On the one hand, they allow modeling different types of diseases and evaluating the efficacy of certain drugs. But they are also of great importance in the field of regenerative medicine. Because they can spread indefinitely, as well as give rise to any other type of cell in the body, they represent a single cell source that could be used to replace those lost due to damage or disease of certain organs.
For all these reasons, iPSC research is essential, in all possible settings. And one of them is space. With this in mind, on May 21, Axiom Space’s private Ax-2 mission will deliver to the International Space Station (ISS) the first stem cells to be grown in space by astronauts aboard the ISS. Growing these cells and causing them to differentiate into specialized cells in space should allow scientists determine if microgravity has any impact in the way that iPSCs develop into other cell types, such as brain and heart cells.
“A major challenge to using iPSCs for human therapies is producing high-quality enough of them,” said Arun Sharma, co-director of research and a cell biologist at Cedars-Sinai in a statement. We want to be able to mass produce them by the billions so that we can use them for a number of different applications, including the discovery of new drugs that can improve heart function. And while we’ve gotten better at this in recent years, there are still certain limitations when it comes to producing these stem cells, and we think microgravity can overcome some of them.”
The limits of gravity
Producing iPSCs on Earth is tricky, in part due to gravitational effects from the planet that can restrict the expansion and growth of these cells. In low gravity environments, such as that of the ISS, this barrier could be removed.
“Gravity is constantly pulling these pluripotent stem cells towards Earth, putting pressure on them and providing a stimulus to start turning into other cell types, but in microgravity, that effect will no longer be there,” adds Clive Svendsen, co-director of the investigation -. By removing gravity from the equation we can see if cells grow faster in space, have fewer gene mutations and remain in their pluripotent state. That is the goal of this new mission.”
The mission will last just one week, but it sets the stage for future longer-duration missions in the coming months that will further test the ability of stem cells to divide and absorb DNA during spaceflight. And also see what happens in the eventual case of a spatial fertilization.