EU Funding, New Regulatory Questions
The five-year PRISM-LT project will run until 2027. Funded by the European Union, it is developing a 3D bioprinting platform for producing living tissues, while researchers and European regulatory authorities consider how future rules and authorisations might apply. The work could lead to tissue models for biomedical research and cultivated meat, though the project coordinators say real-world applications remain distant.
The technology combines living cells with a gel-like support material called bioink. It can also use genetically modified microorganisms, a combination that doesn't fit neatly into frameworks designed for conventional medicines or standard food products. Working with the European Innovation Council, the team is in contact with regulatory authorities, including the European Medicines Agency, to consider future rules and authorisations.
“We have to adopt a new attitude toward this technology,” said Laura Martinelli, PRISM-LT project coordinator and executive director of In Society, a research organization based in Udine, Italy. “This collaboration helps us pave the way for the use of ELMs.”
How the Living Materials Work
The project 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. They can also self-organize and self-repair in ways conventional static materials cannot. “Engineered living materials can have additional, dynamic features that we simply cannot replicate with traditional static materials,” said Massimo Vassalli, the project’s scientific coordinator and chair of bioengineering at the University of Glasgow.
The research team builds tissues from small capsules containing living cells and bioink. Martinelli said the researchers use modular living components rather than printing a continuous stream of bioink. A robotic arm can position the capsules, or researchers can print them in layers. Each capsule contains a scaffold and artificial microorganisms that help guide cell development.
The team genetically modified the microorganisms to detect when stem cells begin to differentiate. They then release chemical signals called growth factors, directing the cells toward a desired tissue type. Manufacturing takes from a few minutes to an hour. Maturation takes about three weeks, while stem cells develop into bone, fat or muscle.
The team currently produces roughly one square centimeter of thin tissue and is working toward a one-cubic-centimeter block. Vassalli said the process must bring together living components not naturally suited to coexist. “We have to create a symbiotic relationship between two systems not designed to live together, like yeast and stem cells,” he said. Creating conditions suitable for both the microorganisms and stem cells during differentiation, he said, remains the main challenge.
Research Uses and Limits
Researchers are working on two tissue types: the interface between bone and adipose tissue found in bone marrow, and muscle-and-fat structures intended to reproduce the marbling that gives natural meat its texture and flavor. The platform could also produce miniature tissue models that mimic human organs for drug testing and personalized medicine.
For healthcare research, the team aims to make three-dimensional bone marrow models to study drugs for diseases such as leukemia. For food applications, 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. She cautioned that practical use remains a long way off. “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.”
Vassalli said engineered living materials could be “extremely powerful” if widely applied. The project began by asking 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, and the article was originally published in Horizon, the EU’s research and innovation magazine.