Genome-edited insulin-producing cells transplanted into type 1 diabetes patient

A patient with type 1 diabetes has been successfully treated with donor pancreas cells modified to evade the immune system.

Islet cells in the pancreas produce insulin, which regulates blood glucose levels. However, in patients with type 1 diabetes, an autoimmune response causes the body to attack and kill these cells. As part of a trial conducted at Uppsala University Hospital in Sweden, a man with lifelong type 1 diabetes received a transplant of genome-edited islet cells from a matched donor pancreas. Despite the patient not receiving immunosuppressive treatment, after 12 weeks the researchers were unable to detect any immune response against the transplanted cells.

'These clinical results are exciting and very promising for patients,' said Professor Per-Ola Carlsson, lead author of the study published in the New England Journal of Medicine. 'It is the first evidence that insulin-producing cells can be transplanted into patients with type 1 diabetes and made to survive without the need for immunosuppressive drugs.'

Many people with type 1 diabetes can control their condition using insulin injections or pumps, and for those with severe disease, transplanting islet cells is an option. However, as with other types of organ transplants, the recipient requires lifelong immunosuppression to prevent their body from rejecting the donor tissue. The immunosuppressive drugs required can have significant side effects and weaken the immune system against genuine threats such as bacteria and viruses.

In this study, the researchers aimed to equip the cells with protection from both rejection and autoimmune attack. They modified donated islet cells using a CRISPR/Cas-based system to knock out two genes involved in the adaptive immune system. They also enhanced the expression of the CD47 gene, which inhibits the activation of immune cells.

While the cohort consisted of only one patient, the study reported no indications of adverse effects or rejection of the transplanted cells over the first 12 weeks of monitoring, as well as consistent and stable insulin secretion.

Professor Carlsson plans to continue monitoring the patient, and added: 'Today's data, combined with progress in producing large quantities of insulin-producing cells from stem cells, gives real hope that a curative treatment can be offered to patients with type 1 diabetes at a large scale.'