Scientists have created 3D-printed devices containing insulin-producing cells that could offer long-term treatment for type 1 diabetes without the need for invasive surgery.
The small implants, designed to be placed just under the skin, would allow people with type 1 diabetes to produce their own insulin, potentially reducing the need for daily injections and constant blood glucose monitoring.
Type 1 diabetes is an autoimmune condition in which the immune system destroys insulin-producing cells in the pancreas. This requires lifelong management, often involving insulin injections and dietary control.
Researchers at the Wake Forest Institute for Regenerative Medicine in North Carolina developed the devices using a “bioink” made from human pancreatic tissue and alginate – a carbohydrate derived from seaweed – mixed with live insulin-producing cells.
One current treatment involves transplanting islets – clusters of insulin-producing cells – into the liver via the portal vein. This is a major surgical procedure, and around half of the transplanted cells lose functionality quickly, often requiring repeat procedures.
Quentin Perrier at the Wake Forest Institute said: “Current practice is to inject these human islets through the portal vein into the liver.
“The higher the density [of islets], the smaller the size of the device you would need to plant in the patient.”
Perrier and his colleagues printed the islets into a porous grid designed to allow new blood vessels to grow into the structure and support cell survival.
Lab tests showed around 90 per cent of the cells remained alive and functional for up to three weeks.
Perrier said: “We put this bioink with the [human] islet into a syringe, and we print a special motif [with it].
The next challenge is really to validate this finding in vivo.”
A parallel project by Adam Feinberg at Carnegie Mellon University in Pennsylvania, working with the biotech firm FluidForm Bio in Massachusetts, uses a different method.
His team prints cells and collagen directly into a hydrogel polymer.
Feinberg explained: “Kind of like 3D printing inside of hair gel.
In laboratory mice with diabetes, the printed islets restored normal blood glucose levels for up to six months.
Placing islets under the skin rather than in the liver could reduce surgical risk and avoid inflammation triggered by liver-based implantation, which can shorten cell lifespan.
The approach may also make treatment more accessible.
Feinberg described Perrier’s results as “definitely promising”, but pointed to a challenge with variability in the donor tissue used to create the islets.
Feinberg said: “It’s like getting a transplant organ.
“On one side, the material may work better. On the flip side, it’s variable and hard to get, and that’s a really hard problem to solve.”