Type 1 diabetes, often referred to as juvenile or insulin-dependent diabetes, is a chronic autoimmune condition in which the body’s immune system mistakenly attacks and destroys the insulin-producing beta cells in the pancreas. This crucial hormone, insulin, plays a vital role in regulating blood sugar levels and facilitating the entry of glucose into cells for energy. As a result of this autoimmune assault, individuals with type 1 diabetes are left with a lifelong dependency on insulin to survive.
Managing type 1 diabetes is a daily challenge. Diabetics need to closely monitor their blood sugar levels and inject themselves with insulin or use insulin pumps to help normalize their glucose levels. Despite their best efforts, achieving consistently healthy blood sugar levels can be elusive because they cannot replicate the pancreas’ natural ability to regulate insulin release in response to changing blood sugar levels. This imbalance can lead to serious complications over time, such as cardiovascular disease, kidney problems, nerve damage, and vision impairment.
Bubbles of oxygen and hydrogen are being produced (📷: Claudia Liu and Dr. Siddharth Krishnan)
One potential alternative to frequent insulin injections or pump use is islet cell transplantation. In this procedure, islet cells, which contain the insulin-producing beta cells, are transplanted into the patient’s liver. However, this approach comes with its own set of challenges. Patients who undergo islet cell transplantation typically need to take immunosuppressive drugs to prevent their immune system from attacking the newly transplanted cells. These drugs can have potentially harmful side effects and weaken the body’s ability to fight infections.
Another approach is to encapsulate the islet cells to protect them from the immune system’s attacks. While this method can be effective in preventing rejection, it introduces another problem: the encapsulated cells eventually run out of oxygen, leading to their death.
Brighter days may be ahead for diabetics, thanks to the recent work completed by a team led by researchers at MIT. They have developed an implantable device containing hundreds of thousands of islet cells. The islet cells are encased to keep them from interacting with the immune system. But where this device differs from existing solutions is in its onboard electronics that operate a tiny oxygen production factory that keeps the islet cells healthy.
The implant borrows a technology originally intended to generate hydrogen in fuel cells — proton-exchange membranes. These membranes split the water that is naturally found in the body into hydrogen and oxygen. The hydrogen harmlessly diffuses away, while the oxygen passes through an oxygen-permeable membrane to supply the islet cells with the life-sustaining substance.
The implant requires only 2 volts of electricity for operation, and this is wirelessly transmitted to it via a magnetic coil located outside the body through resonant inductive coupling. The team noted that these external components could be worn as a skin patch on the body.
The fully assembled implant (📷: Claudia Liu and Dr. Siddharth Krishnan)
The prototype device was tested on diabetic mice, and was found to maintain safe levels of blood sugars for a period of one month, but the device could potentially operate normally for much longer, thanks to the oxygen factory. Further experiments will be required to determine exactly how long the implant will stay functional. Looking beyond the mouse trials, the researchers plan to build a larger device, about the size of a stick of chewing gum, for use in humans with type 1 diabetes.
With the early successes seen in the experiments, there is hope for a future where diabetics not only no longer need to inject insulin, but also where their blood sugar levels can be maintained at healthier levels. And that could prevent many diseases and other problems.
Further down the road, the researchers plan to investigate how they might leverage their technology to deliver other types of proteins to the body that must be administered over long periods of time.