The latest in futuristic Type 1 diabetes therapy: scientists from the University of Tokyo have developed a new device, inspired by shape of the lotus root, to protect lab-grown and transplanted beta cells from the body’s immune system.
Many researchers around the world are investigating human pluripotent stem cells as a therapy for diabetes. These cells have the capability of growing into any type of human cell; for diabetes technologists, that means an essentially inexhaustible supply of fresh, healthy beta cells.
In theory, transplanted beta cells could effectively treat or even cure Type 1 diabetes. Animal studies have suggested that such a cure may indeed be seen in our lifetimes. But it’s not so easy as transplanting new cells into the diabetic body. The problem is protecting them from the autoimmune reaction that precipitated beta cell destruction in the first place.
Professor Shoji Takeuchi, the lead author of the study describing the novel technique, explained the difficulties his team was up against: “The challenge arises from the difficulty to make large amounts of human beta-cells in a dish, and more importantly, to achieve safe and effective transplantation. In this study, we wanted to develop a novel construct that enables successful transplantation of beta-cells in the long-term.”
Professor Takeuchi’s team hoped to improve upon the design of a kind of implantable container that had previously been developed to house and protect the beta cells. This device had mixed success; while the container did effectively shield them from the immune system, only the transplanted cells within a millimeter of the edge of the container received enough oxygen and nutrients to survive.
Enter the lotus, long a beloved symbol of enlightenment in Japan. It wasn’t the flower that inspired the team, but the root, which is a popular vegetable in the country. The shape of the lotus root maximizes surface area, ensuring that all of the transplanted beta cells are within reach of the barrier.
To test their design, the researchers implanted beta cells in their lotus-shaped container into the bodies of diabetic mice. They found that the mice’s blood glucose levels stayed steady and healthy for 180 days, after which the device was easily removed, without complications. Success! We can hope that trials with human patients will soon follow.
The University of Tokyo team used special stem cells named iPSC’s: induced pluripotent stem cells. iSPC’s are grown directly from adult tissues—mature cells are actually reprogrammed to become immature, pluripotent cells, which can then be encouraged to grow into beta cells or any other type of cell. What’s additionally notable about iSPCs is that they do not require the use of embryonic stem cells, which have been something of a political hot button. Their discoverer, Japanese scientist Shinya Yamanaka, was awarded the Nobel Prize in Physiology or Medicine in 2012.
Several teams are working on similar solutions and coming up with their own ways to deal with the same problems. In January, we reported on the medical technology firm Vertex and its billion-dollar bet on beta cell transplantation. The man behind that therapy, Harvard’s Dr. Douglas Merton, has stated that he is “convinced that those cells will cure the disease.” Vertex has explored at least two different ways to defend its cells against the onslaught of the immune system. In its first step up to the plate—Vertex has received an FDA-approval to begin patient trials—the company will administer immunosuppressive drugs along with its islet cell transplantation. Vertex is also reportedly working on a similarly creative manner of protecting its cells, implanting them in a kind of porous “tea bag” that would allow glucose and insulin to pass through, but block the cells of the immune system.
It will likely be years before we can begin to realistically talk about federal approval for stem cell-derived therapies in Type 1 diabetes. But it’s still exciting to track the progress here on the vanguard of futuristic diabetes technology.
