2025-08-13
A new study published in NEJM shows CRISPR-edited islet cells can function in a person with type 1 diabetes without immunosuppression.
A first-in-human study led by Professor Per-Ola Carlsson at Uppsala University Hospital shows that gene-edited islet cells can survive and function without immunosuppression. The results were presented during the #WTC2025 Congress and published simultaneously in The New England Journal of Medicine.
The study introduces a hypoimmune approach to treating type 1 diabetes. A single patient with long-standing T1D received gene-edited allogeneic islet cells, engineered using CRISPR-Cas12b to:
Knock out HLA class I and II, reducing immune detection
Overexpress CD47, protecting cells from innate immune attacks
These cells were transplanted into the patient’s forearm muscle without immunosuppressive therapy. At 12 weeks post-transplant, C-peptide levels confirmed functional insulin production, and no immune response was detected against the transplanted cells.
No serious adverse events were reported.
The results were presented by Dr. Sonja Schrepfer (University of California, San Francisco) at the World Transplant Congress (WTC 2025). The study represents a collaboration between Uppsala University Hospital, Oslo University Hospital, and Sana Biotechnology.
“Proof of concept: primary islet cells can be transplanted without immunosuppression and replace lost islet function in T1D,” noted Schrepfer.
By demonstrating that hypoimmune allogeneic islet cells can persist and function in humans without immune suppression, this study marks a significant step forward for cell therapy. It also highlights the potential of genetic engineering technologies—such as CRISPR-Cas12b—to overcome major barriers in ATMP development.
Read the full study:
Survival of Transplanted Allogeneic Beta Cells with No Immunosuppression — NEJM