NASA’s partner sends human cells to space to study aging

A team of scientists and the International Space Station (ISS) National Lab sent tissue chips into space to research immune cells and find ways to stop them from aging.

With the help of the ISS National Laboratory, a team of scientists conducted a study on how the human immune system works in microgravity. It’s known that microgravity affects the human immune system, causing dysfunction in healthy astronauts during spaceflight.

The decline in astronauts' immune system capacities is similar to that caused by aging but in a more accelerated way. This makes space a perfect place to study the aging process of the immune system.

“By sending immune cells into space, we were able to simulate the aging process of the immune system and better understand how it affects our body’s ability to repair itself as we grow older,” said Sonja Schrepfer, a research lead and a professor of surgery from the University of California.

The immune system constantly fights viruses and bacteria to protect the body from hazardous effects. This exhausts the system over time, leading to what scientists call an ‘aged immune system.’

Immune system decline, whether due to age or chronic illness, often means a heightened risk of severe outcomes from diseases, as well as impeding the body's ability to heal wounds.

“We’ve seen evidence of decreased wound healing in space, which means the immune system is not functioning as it should be,” said NASA astronaut Kjell Lindgren, who took care of research specimens during the spaceflight experiment.

“The research that we do on station correlates to disease processes in the human body on Earth, and to be able to work on an experiment that has a direct benefit for people on Earth is really exciting.”

Used a special chip design

The research took place during SpaceX’s 16th Commercial Resupply Services (CRS) and SpaceX CRS-25 missions, when the small devices, called tissue chips, were sent to space.

The devices were built to mimic human tissue so they could provide more accurate results for cell behavior study than the traditional rodent models. The scientists also had to use specific tissue chip hardware, which helped to accommodate the three different types of cells that were flown into space.

According to Schrepfer, the design of the chips was crucial in the research. Its task was to enable the return of live tissue specimens back to the Earth’s surface for further observation in regular gravity conditions.

Sadly, no way to reverse aging

Results of the experiment in space confirmed that microgravity induces a decline in immune function similar to that caused by the aging process on Earth, but at a significantly accelerated rate. Effects of aging appeared in as little as three days.

Apparently, microgravity triggers an excessive inflammatory response that has a negative impact on stem cell function. It can reduce the body’s ability to heal wounds and get rid of invaders like viruses.

Sadly, once the cells landed back on planet Earth, the immune dysfunction remained. This means that the scientists are not yet able to identify a way to reverse immune aging.

“Unfortunately, we learned that we cannot reverse immune cell aging, but we may be able to treat it,” Schrepfer said. “That’s something we are looking into and are excited to explore more.”

Nonetheless, results provided new insights into the mechanisms behind immune system function, which could lead to further research aimed at combating diseases and helping patients respond better to vaccines.