Interstellar Insights: Revolutionizing Heart Cell Therapy Through Space Research

A group of scientists directed by Emory’s Chunhui Xu recently discovered that cardiac muscle cells can proliferate -and persist in the microgravity conditions of space. Her research, published in Biomaterials, indicates potential for creating sturdier heart cells capable of effectively mending impaired hearts in cell therapy – the procedure of transplanting millions of heart cells to mend damaged hearts – here on earth.

The concept behind cell therapy is to regenerate new muscle. However, survival is the challenge. Specifically for heart muscle, once it is damaged, it cannot regenerate. Following the injection of new cells into the affected area, numerous cells are often lost.”

Chunhui Xu, professor of pediatrics, Emory University School of Medicine

Building on previous studies indicating that cancer cells proliferate more quickly in space, Xu’s team initially attempted to replicate microgravity by placing heart cells in a random positioning device, which continuously altered the cells’ orientation, preventing them from acclimating to a fixed direction. The elevated survival rates of these cells led them to investigate whether the unique conditions of space could induce molecular transformations in heart cells, enhancing their likelihood of surviving once reintroduced into a patient on earth. “In space, the cells can genuinely detect that new environment and adapt,” Xu explains.

The transition from the laboratory to the space station

Xu’s investigation utilized specialized heart muscle cells that contract at consistent intervals and together, enable the cells to pulse like a healthy heart. These cells originated from generic human stem cells that could differentiate into various cell types. Previous experiments had shown similar cell groups prevented heart failure in preclinical trials. This prompted numerous researchers to conclude that if a method could be found to enhance the survival of these cells in cell-based heart therapy, there could be an unlimited source of new cells for human heart restoration. The difficulty lay in discovering methods to boost the survival rate of the transplanted cells.

In their experiments, Xu’s team assembled clusters of heart muscle cells into tiny three-dimensional spheroids that simulated the structure and function of the human heart. The cells were frozen for their journey to the International Space Station (ISS) and thawed right before the launch. Control groups of heart cell clusters remained on earth for comparative analysis. Astronauts aboard the ISS employed microscopes to monitor the progress of the orbiting heart cells and sent back videos showcasing the growth of the cells.

After eight days in space, they returned live cell cultures to earth. Once the spaceflight concluded, both the ground-based and space-traveling cells underwent characterization to examine the unique molecular alterations that transpired in cells subjected to microgravity. The findings were intricate but revealed a trend of heightened production of proteins associated with cell survival.

Gaining insight into how the microgravity environment modifies the molecular behavior of heart cells to enhance their survivability could represent significant progress in utilizing these cells to efficiently repair damaged hearts. A thorough understanding of all processes related to cell survival and growth for heart muscle cells under stress situations will be essential. This information may pave the way for developing heart cells on earth with improved survival outcomes.

“Instead of dispatching cells to space,” Xu states, “We essentially need to devise new methods to understand the molecular transformations that enhance cell survival, enabling us to modify these changes when preparing the cells on earth. Then, we aspire to formulate a new strategy to create superior cells for cell therapy.”

This research was executed in partnership with BioServe Space Technologies and Georgia Institute of Technology with financial support from the National Science Foundation and backed by the ISS National Laboratory.