Stem cell therapy brings new hope to diabetics

Tokyo-A new technology that can grow insulin-producing cells and protect them from immune attack after transplantation may bring new hope to the treatment of some diabetics.

In type 1 diabetes, the body turns on itself and attacks so-called beta cells within a cluster of pancreas called an “islet.”

These beta cells measure sugar levels in the blood and release insulin to keep them stable. Without them, diabetics would have to resort to insulin injections or pumps.

One treatment devised to eliminate addiction involves transplanting a donor island into a diabetic patient, but several obstacles, including a lack of donors, complicate the process.

Islets also often fail to connect to the blood supply and, like other transplants, can be attacked by the immune system of the recipient who views the cells as invaders, even when they are connected. There is.

As a result, patients must take drugs that suppress the immune system, which protects the transplant, but can leave the rest of the body ill.

To overcome some of these challenges, teams coordinate induced pluripotent stem cells (iPS) to produce what are called HILO, or organoids that resemble human islands, thereby creating another source of islands. I searched for.

These HILO, when grown in a 3D mimicry of the pancreas and turbocharged with a “gene switch,” produced insulin normally and were able to regulate blood glucose when implanted in diabetic mice.

“In the past, this function was achieved only after one month of maturation in living animals,” said Ronald Evans, director of the Gene Expression Lab at the Salk Institute for Biological Studies.

“This breakthrough allows us to produce functional HILO that is active on the first day of transplantation, which will bring it closer to clinical applications,” Evans, who led the study, told AFP.

-Give hope-

Scientists who have found potential ways to solve supply chain problems have addressed the issue of immune rejection.

They focused on a so-called checkpoint protein known as PD-L1, known to block the body’s immune response.

In cancer treatment, drug therapy may be used to block PD-L1, increasing the body’s immune response to cancer cells.

The team effectively reversed that process, inducing HILO to express a protein to betray the immune system.

“Usually, human cells in mice will be cleared within a day or two,” Evans said.

“We have found a way to create an immune shield that hides human cells from the immune system.”

HILO transplanted into PD-L1 unprotected mice gradually stopped functioning, but HILO induced to express protein was shielded and continued to help diabetic mice regulate blood glucose for over 50 days. It was.

“The ability to grow insulin-producing cells and protect them from attack will “close the door to potential treatments for people with type 1 diabetes,” Evans said.

By 2014, approximately 422 million people had diabetes worldwide, according to the World Health Organization, which includes both type 1 and type 2 diabetes.

Islet transplantation is commonly considered as a treatment for people with type 1 diabetes, a disease that is the result of an autoimmune reaction.

Evans warned that the study, which has been over 10 years old, will take years before it can treat diabetes in humans.

“To get HILO into the clinic we need to make sure it works in other animal models, including primates, and that we do long-term studies in mice,” he said.

He hopes human studies of this technology will be possible in two to five years.

“This is a difficult disease to manage and insulin is not a cure,” he added, pointing out that 1.6 million children and teens live with Type 1 diabetes in the United States alone.

“Good science is more than a discovery. It can enrich the world and give hope to those living with disease.”