ESA studies growing blood vessels in zero gravity

ESA scientists are experimenting with growing blood vessels in the weightlessness of space. Based on the Spheroids experiment that flew to the International Space Station (ISS) in 2016, the researchers found that in microgravity blood vessel cells organized themselves in a way similar to that of cells inside the body.

Being able to grow blood vessels from human cells has great potential for treating a wide range of diseases but getting those cells to cooperate and form themselves into proper vessels is far from easy. To do so, scientists have to coax the cells by implanting them into biocompatible scaffolds because under the force of gravity the cells tend to settle to the bottom of the Petri dish or get dislodged by convection forces.

However, in zero gravity, there’s nothing to pull or push the cells out of place, allowing them to form themselves into simple 3D structures, including globules and tubes. For the Spheroids experiment, the endothelial cells that form the inner lining of blood vessels and control their contraction and expansion were cultivated for 12 days inside ESA’s Kubik incubator.

“These tube-like aggregations resembled rudimentary blood vessels, something never achieved before by scientists cultivating cells on Earth,” says Daniela Grimm of the Otto von Guericke University Magdeburg, Germany. “Nobody knew how the cells would react to space. The Spheroids project has been an exciting adventure from the very beginning.”

Back on Earth, the ESA team not only analyzed the results of the Spheroids experiment but built on them, finding that the space incubation confirmed that gravity affects how key proteins and genes interact. The researchers were also able to culture different cells together using a random-positioning machine to simulate weightlessness to produce several layers of blood vessel tissue.

According to ESA, being able to cultivate artificial blood vessels would not only have surgical applications but could also improve our understanding of a range of blood-vessel-related diseases and the effects of weightlessness on the human body.