Scientists create functional 3D printed human islets for type 1 diabetes treatment

A team of international scientists have made a major leap into diabetes research by 3D printing functional human islands using the new Bioink. Announcing today at ESOT Congress 2025, this new technology could pave the way for more effective and less invasive treatment options for those living with type 1 diabetes (T1D).

The breakthrough involved printing clusters of insulin production of pancreatic cells using customized bioinks made from alginate and decellularized human pancreatic tissue. This approach produced a durable, high density island structure. This has lived up to 3 weeks, maintained functionality, maintained a strong insulin response to glucose, indicating the true potential for future clinical use.

Traditional islet transplants are usually injected into the liver. This is a process that can lead to significant cell loss and limited long-term success. In contrast, the 3D printed islands of this study are designed to be embedded just below the skin, and are a simple procedure that requires only local anesthesia and small incisions. This minimally invasive approach may provide a safer and more comfortable option for patients.

“Our goal was to replicate the natural environment of the pancreas so that the implanted cells survive and function better,” explained lead author Dr. Quentin Perrier. “We used special bio-inks that mimic the pancreatic support structures, providing the islets with the oxygen and nutrients they need to thrive.”

To keep the fragile human island safe during printing, the team created a gentle way to print by fine-tuning key settings using low pressure (30 kPa) and slow printing speeds (20 mm per minute). This careful approach helped reduce the physical stress of the islets and maintain its natural form, solving a major problem that had hampered previous bioprinting attempts.

Clinical tests showed that bioprinted islets remained vibrant and healthy with cell survival rates of over 90%. They also responded better to glucose than standard islet formulations and released more insulin when needed.

By day 21, bioprinted islets showed strong ability to sense and respond to blood glucose levels. Importantly, the constructs maintain the structure without coagulating or breaking, and overcame the general hurdles in previous approaches.

Furthermore, the 3D printed structures featured a porous architecture that enhanced the flow of oxygen and nutrients to the embedded islets. This design not only helped maintain cell health, but also promoted angiogenesis. Both are important for long-term survival and function after implantation.

“This was one of the first studies to use real human islets instead of animal cells in bioprints, and the results are extremely promising,” says Dr. Perrier. “That means we're approaching creating ready-made treatments for diabetes that one day eliminate the need for insulin injections.”

The team is currently testing bioprinted constructs for animal models and investigating long-term storage options, such as cryopreservation, making treatments widely available. They are also working on adapting methods for alternative sources of insulin-producing cells, overcoming donor shortages including stem cell-derived islets and xeno islets (from pigs).

“There's still work to do, but this new bioprinting method illustrates an important step towards personalized, implantable treatment for diabetes. Ascertaining its effectiveness in clinical trials can change the treatment and quality of life for millions of people around the world,” concluded Dr. Perrier.

Provided by the European Organ Transplant Association