Biological Space Experiment at ISS Sheds Light on Immune System

A key part in the mechanism activating the human immune system has been identified by researchers thanks to an experiment conducted on board the International Space Station (ISS). The finding could help to pro-actively our immune system earlier and more specifically in order to quell diseases before they really begin and damage our body.

It is known that the immune systems of astronauts are weakened in space, ever since the first humans ventured into space and common infections turned out to be more grave than on Earth. But it was a mystery until now what was blocking astronauts' immune systems from working normally.

In a straightforward experiment to compare the difference in cells behavior, German ESA astronaut Thomas Reiter performed an experiment on the International Space Station in 2006 using ESA's Kubik space incubator: One batch of human immune cells was allowed to float in microgravity while another was held in a centrifuge to simulate gravity. The cells were preserved for analysis back on Earth.

Nor surprisingly, the cells that experienced a weightless environment didn't do very well, while the ones in simulated gravity as if on Earth were found to be in good health. Since the two samples could be compared in depth on earth, investigators eventually found what was stopping the immune cells from working properly. A specific transmitter in the immune cells, called the Rel/NF-B pathway, stops working in weightlessness.

"Normally, when our bodies sense an invasion, a cascade of reactions occur that are controlled by the information held in our genes, similar to an instruction book," explains Isabelle Walther, an investigator based in Zurich, Switzerland. "Finding which gene does what is like looking for the right key to fit a keyhole, without having found the keyhole yet."

Thus, studying cells that have flown on the International Space Station is putting researchers on the right path to finding the key to how our immune system works. Comparing samples is showing them where to look to find which genes instruct our immune cells to react to diseases, and how.

"We are working towards a finer control of disease," says Millie Hughes-Fulford, NASA astronaut and a investigator on this experiment.

This new findings could lead to new breakthroughs in two areas: Stopping genes that activate our immune system would help to relieve people suffering from autoimmune diseases such as arthritis. And even better, pharmaceutical industry could identify specific genes that need to be activated to fight specific illnesses and manufacture tailored antibodies.

"If you imagine our immune system responding to diseases as a waterfall," explains Millie, "up until now we have been fighting disease at the bottom of the waterfall."

"In the future we could target the raindrops before they have a chance to cascade into waterfalls. We live in exciting times."