For people with Type 1 diabetes, insulin is essential—but it does not stop the autoimmune attack that destroys the pancreas’s insulin-producing beta cells. New research from the Medical University of South Carolina (MUSC) suggests a potential strategy to address that underlying immune dysfunction. In a mouse model of newly diagnosed Type 1 diabetes, researchers used genetically engineered mesenchymal stem/stromal cells to reverse disease, pointing toward a possible future treatment that protects remaining insulin-producing cells rather than only replacing the insulin they can no longer make.
Type 1 diabetes develops when the immune system mistakenly targets beta cells in the pancreas. Without enough functioning beta cells, the body cannot make sufficient insulin to regulate blood glucose. Insulin injections, pumps, and continuous glucose monitors have transformed diabetes care, but they do not halt the immune process or fully prevent long-term complications. That is why researchers continue to look for treatments that can preserve beta cells and restore immune balance—especially soon after diagnosis, when some insulin-producing capacity may remain.
The MUSC team, led by Hongjun Wang, Ph.D., focused on mesenchymal stem/stromal cells, commonly called MSCs. These adult cells are of interest because they can influence inflammation, support tissue repair, and regulate immune activity. Previous clinical studies have suggested that standard MSC therapy may help preserve residual insulin production in people with Type 1 diabetes. However, established autoimmune inflammation can be intense enough to limit how well conventional MSCs work.
To strengthen the cells’ therapeutic potential, the researchers engineered MSCs to produce alpha-1 antitrypsin, or AAT. AAT is a protein with anti-inflammatory and tissue-protective properties. The resulting AAT-MSC therapy was designed to deliver a two-part effect: help protect surviving pancreatic beta cells while also dampening the damaging immune response directed against them. The study was published in Molecular Therapy.
In the mouse model, the therapy did more than broadly suppress inflammation. The researchers used single-cell analysis to examine how it changed the immune system and found evidence of immune “reprogramming.” AAT-MSC treatment increased regulatory T cells—immune cells that help maintain tolerance and prevent inappropriate immune attacks. At the same time, it reduced the activity of CD8+ T cells, often called killer T cells, which are among the immune cells involved in beta-cell destruction in Type 1 diabetes.
This balance matters. In Type 1 diabetes, regulatory T cells may be present but unable to keep pace with aggressive autoimmune cells. By increasing the regulatory side of the immune system and pushing destructive T cells toward exhaustion, the engineered MSCs appeared to create a more protective environment for pancreatic tissue. In the study, this shift was associated with reversal of new-onset diabetes in mice.
Another intriguing finding involved durability. The infused MSCs themselves were cleared from the body within hours or days, according to the MUSC report, but their immune effects persisted. The researchers suggest the cells may release small molecular factors that continue influencing immune activity and protecting organs after the cells are gone. If this concept translates to people, it could make cell therapy a temporary intervention with longer-lasting biological benefits.
It is important to keep the study in perspective. These findings come from an animal model, not a completed human trial, so the treatment has not been proven safe or effective for people with Type 1 diabetes. Results in mice frequently do not translate directly to patients, and engineered cell therapies require rigorous testing for safety, dosing, durability, manufacturing quality, and potential immune effects.
Still, the research offers a compelling direction for Type 1 diabetes care: combining regenerative cell therapy with targeted immune modulation. The MUSC team is already evaluating MSC-based approaches in patients with newly diagnosed Type 1 diabetes and hopes eventual early trials could lead to a larger multicenter study. The researchers are also exploring whether this immune-reprogramming strategy could be relevant to other autoimmune and inflammatory diseases, including lupus and chronic pancreatitis.
For now, AAT-MSC therapy remains experimental. But the work reinforces a central goal in diabetes research—to move beyond managing blood sugar and toward preserving or restoring the body’s own ability to regulate it.
