How can the microscopic creatures, tardigrades, also called water bearers, help contribute to developing new medical treatments? This is what a recent study published in Protein Science hopes to address as a team of international researchers investigated how tardigrade proteins could replace certain medical treatments when refrigerating those treatments are unavailable, specifically regarding stem cell treatments, and could possibly slow the aging process.

One reason tardigrades are an intriguing option is due to their ability to start and stop suspended animation when presented with outside stressors. Now, researchers are attempting to introduce tardigrade proteins in human cells, and the researchers have found some surprising results.

“Amazingly, when we introduce these proteins into human cells, they gel and slow down metabolism, just like in tardigrades,” said Dr. Silvia Sanchez-Martinez, who is a Senior Research Scientist at University of Wyoming and lead author of the study. “Furthermore, just like tardigrades, when you put human cells that have these proteins into biostasis, they become more resistant to stresses, conferring some of the tardigrades’ abilities to the human cells.”

The results of the team’s research showed that the approach, targeting a subset of hematopoietic stem cells (HSCs) that increase with age, rebalanced blood-cell production and reduced age-related immune decline. The treatment significantly improved the ability of geriatric animals’ immune systems to tackle a new virus, and to respond to vaccination, enabling the animals to fight off a new viral threat months later.

“This is a real paradigm shift—researchers and clinicians should think in a new way about the immune system and aging,” said Stanford postdoctoral scholar Jason Ross, MD, PhD. “The idea that it’s possible to tune the entire immune system of millions of cells simply by affecting the function of such a rare population is surprising and exciting.”

Weissman, who is professor of pathology and of developmental biology, and Kim Hasenkrug, PhD, the chief of Rocky Mountain Laboratories’ Retroviral Immunology Section, are senior authors of the team’s published study in Nature, titled “Depleting myeloid-biased haematopoietic stem cells rejuvenates aged immunity.” Ross and Lara Myers, PhD, a research fellow at Rocky Mountain Laboratories, are lead authors of the report, in which the team concluded, “The clinical development of safe protocols to rebalance HSCs could have broad effects on a number of age-associated issues.”