Surgeons and medical researchers may soon witness significant advancements in tissue engineering and liver transplantation driven by unique research aboard the International Space Station (ISS).
Spearheaded by Tammy T Chang, at the University of California, San Francisco, the Chang Laboratory for Liver Tissue Engineering is at the forefront of leveraging the low Earth orbit (LEO) environment – located below 1,200 miles altitude – to drive the self-assembly of functional liver tissues.
This cutting-edge approach, which harnesses the benefits of microgravity, could redefine complex tissue development and address fundamental limitations in terrestrial methods.
Dr Chang and her team plan to present findings and logistical insights regarding space-to-Earth tissue transport at the upcoming American College of Surgeons (ACS) Clinical Congress 2024 in San Francisco.
On Earth, scaffolds and artificial matrices serve as cellular frameworks, but these foreign materials can interfere with natural cellular behaviour.
In contrast, the microgravity environment allows cells to assemble more freely, improving their differentiation and more accurately mimicking organ-like structures.
Dr Chang highlights: ‘Our experiments have shown that liver tissues cultured in microgravity exhibit superior differentiation and functional attributes compared to those developed with Earth-bound methods. This paves the way for potentially viable tissue grafts as alternatives or supplements to liver transplantation.’
The laboratory’s research involves cultivating induced pluripotent stem cells (iPSCs), reprogrammed from adult human cells to behave like embryonic stem cells and offer pluripotent capabilities.
Under microgravity, these iPSCs are encouraged to self-organise into liver tissues that simulate essential hepatic functions.
This contrasts with Earth-based protocols that rely heavily on exogenous supports, which can hinder cells’ natural organisation.
Central to the success of this research is a specially engineered bioreactor, the ‘Tissue Orb’.
This device incorporates an artificial circulatory system with automated media exchange, fostering tissue growth that emulates in vivo blood flow.
A critical hurdle is preserving and safely transporting these tissues back to Earth. To this end, the team is advancing cryopreservation methods such as isochoric supercooling, which enables sub-freezing storage without crystallisation damage.
Such technology could extend the usability of bioengineered tissues and even whole organs, impacting the entire field of transplantation.
Dr Chang said: ’Our mission is to refine preservation processes to deliver functional tissue to surgeons and researchers on Earth for therapeutic use, as well as for disease modelling and drug discovery.’
This spaceflight project, scheduled for a February 2025 launch, aims to demonstrate that microgravity-based engineering holds promise for clinical and surgical applications.
The research lays foundational work for potential space-based biomanufacturing solutions that can extend the frontiers of surgical practice.
This endeavour is supported by grants from the National Science Foundation (NSF), the ISS National Laboratory (ISSNL), and NASA’s Translational Research Institute.
Co-authors include Juan C. Reyna, Anthony N Consiglio, Alan Maida, Maria Sekyi and Boris Rubinsky.
