The EU-funded PRISM-LT project is developing a 3D bioprinting platform for living tissues, while researchers work with regulators on how authorities should authorise the technology. The five-year project will run until 2027. Its work could support bone marrow research, miniature tissue models and cultivated meat.
Building tissue from living components
PRISM-LT develops engineered living materials, or ELMs: composite materials made wholly or partly from living cells, including microorganisms such as bacteria or fungi. They can grow, respond and adapt to their surroundings, and can self-organise and self-repair, according to scientific coordinator Massimo Vassalli, chair of bioengineering at the University of Glasgow.
“Engineered living materials can have additional, dynamic features that we simply cannot replicate with traditional static materials,” Vassalli said. The project aims to understand how living tissues form and how researchers can recreate them in laboratories.
The team makes tissues from small capsules containing living cells and a gel-like support material called bioink. “Instead of printing a continuous stream of bioink, we work with modular living components that are encapsulated,” said Laura Martinelli, project coordinator and executive director of In Society, a research organization based in Udine, Italy.
A robotic arm positions the capsules, or a printer arranges them layer by layer. Each capsule contains a scaffold and artificial microorganisms that help guide cell development. Researchers genetically modified the microorganisms to detect when stem cells begin to differentiate, then release growth factors that direct them toward a desired tissue type.
Manufacturing takes from a few minutes to an hour. The tissue then matures for about three weeks as stem cells develop into bone, fat or muscle. The team can currently produce roughly one square centimeter of thin tissue and is working toward a one-cubic-centimeter block.
Medical research and cultivated meat
Researchers are working on two tissue types: the interface between bone and adipose tissue found in bone marrow, and muscle-and-fat structures designed to reproduce the marbling responsible for natural meat’s texture and flavor. The project also aims to create miniature tissue models that mimic human organs, with potential uses in drug testing and personalized medicine.
For health research, the team aims to make three-dimensional bone marrow models to study drugs for diseases such as leukemia. For food, Martinelli said the distribution of adipose tissue matters for consumer acceptance. “Thanks to our bioprinting technology, we can achieve the right texture in alternative meats, which gives us the opportunity to commercialize them,” she said.
The researchers chose yeast rather than bacteria for cultivated meat. “It would be hard to explain to consumers that meat was made using bacteria,” Martinelli said. Practical uses remain distant, she cautioned: “We are still far from real-world applications. We focus on principles and mechanisms to see what is viable. However, we are already considering future challenges.”
Regulatory questions ahead
ELMs combine living cells and, in some cases, genetically modified microorganisms. The article says they don’t fit neatly into regulatory frameworks designed for conventional medicines or standard food products.
Working with the European Innovation Council, the project team is in contact with regulatory authorities, including the European Medicines Agency, to examine future rules and authorisations. “We have to adopt a new attitude toward this technology,” Martinelli said. “This collaboration helps us pave the way for the use of ELMs.”
Vassalli said the project initially asked whether the technology was viable and scalable. “Now we can say it is viable,” he said. Scaling up is the next challenge. The European Innovation Council partly funded the research, which Horizon, the EU’s research and innovation magazine, reported.