Scientists designed self-policing T cells to stop the immune system from attacking insulin-producing cells in mouse trials, suggesting a way to reverse diabetes.

People with Type 1 diabetes rely on supplemental insulin to survive as their immune system destroys their body’s insulin-producing cells. Clinical trials from the Medical University of South Carolina reversed newly diagnosed Type 1 diabetes in mice by reprogramming the immune system to protect insulin-producing cells.

Lead researcher Hongjun Wang said the experimental therapy uses adult stem cells derived from donated umbilical cords to help repair tissue and control immune activity, even after the onset of diabetes damages those tissues.

“While insulin injections are lifesaving, they cannot stop immune attacks, and they do not prevent long-term complications,” Wang told SciTechDaily.com. “This study suggests a new way to treat Type 1 diabetes by addressing the root cause — immune system dysfunction — rather than just managing blood sugar.”

Insulin is essential for regulating blood sugar and helps cells absorb it for energy, according to the National Institutes of Health. The disease affects about 1.7 million American adults, or one in 20 people with diabetes.

Diabetes causes damage from high blood sugar levels that can harm the heart, kidneys, nerves, eyes, feet and teeth. It also contributes to high blood pressure and cholesterol problems. Symptoms include increased urination, feeling very thirsty or hungry — even after eating — blurred vision, fatigue, sores that do not heal, frequent infections and unexplained weight loss.

The success of the new treatment depends on diagnosing diabetes early, before the body’s insulin-producing cells are wiped out. After treating mice, the researchers reported an increase in protective T-regulatory cells and a drop in active attacking cells. These results continued long after the stem cells finished their work and disappeared from the body.

They published their work in the journal Molecular Therapy on July 1.

The NIH approved a human trial for 60 participants aged 18 to 40 who are within their first six months of a Type 1 diabetes diagnosis. That trial will begin next February.

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