Cells invisible to the immune system bring a possible cure for type 1 diabetes closer.

An innovative treatment based on gene-edited cells has proven effective in treating type 1 diabetes in a small trial just published in The New England Journal of Medicine . The treated patient remained 12 weeks without the need for any immunosuppressive drugs to control his disease.

In December 2024, a 42-year-old Swedish man with 37 years of type 1 diabetes received 17 injections containing approximately 80 million genetically modified donor pancreatic beta cells.

The goal of this team from Uppsala University Hospital (Sweden) was to make these insulin-producing cells invisible to the immune system, thus avoiding the use of immunosuppressive drugs.

The cells, from a matched deceased donor pancreas, were isolated and edited using CRISPR-Cas12b molecular scissors to eliminate two genes in particular—B2M and CIITA—responsible for the expression of the HLA-I and HLA-II molecules that cause rejection.

To prevent them from being rejected by the patient's immune system, the cells were modified with a lentiviral vector that overexpressed a protein that sends " don't eat me " signals to immune cells (CD47). Finally, they were reassembled before transplantation.

No glucocorticoids, anti-inflammatory drugs or immunosuppressants were administered.

As expected, the immune system attacked the transplanted cells with full force for 84 days. Despite this, the modified cells maintained insulin production and improved glucose control, with viable grafts and no inflammation.

Although the patient still requires immunosuppression, the survival and functionality of the grafts without immunosuppression is considered a proof-of-concept success. "We transplanted 7% of the curative dose of cells," Per-Ola Carlsson , leader of the Uppsala research, told Science magazine. But the patient also did not require immunosuppressive drugs. " In my opinion, this is a great success ."

Researchers say the cells' demonstrated ability to evade immune destruction without systemic drugs opens the door to a potentially curative cell therapy for type 1 diabetes, with the prospect of reducing complications and improving the quality of life for millions of people.

This isn't the first stem cell approach to curing diabetes. A Vertex Pharmaceuticals trial has successfully gotten patients to stop taking insulin, albeit with immunosuppression.

Another paper published in Cell reported the case of a 25-year-old woman with type 1 diabetes who was able to produce insulin on her own and go without injections for over a year after receiving a transplant in 2023 of pancreatic islets generated from reprogrammed stem cells from her own body. The procedure used iPS cells transformed into islets and implanted in the abdominal muscles, allowing for MRI monitoring.