A 42- year-old man with type 1 diabetic begna making his own insulin without daily shots or anti-rejection medication. The breakthrough, published in the New England Journal of Medicine, is being hailed as the most promising advancement on the way to a functional cure for type 1 diabetes, an autoimmune disease that afflicts nearly 9.5 million people globally. It signaled the start of a diabetes revolution. For the first time, researchers have been able to transplant genetically modified islet cells into a human patient, allowing the body to produce insulin naturally and prevent immune rejection—a hurdle that has hampered advances for decades.Type 1 diabetes develops when the immune system attacks and destroys the pancreatic islet cells that make insulin. In its absence, the body is unable to control blood sugar, and patients must depend on man-made insulin injected or pumped into the body.Although insulin therapy is life-saving, it cannot duplicate the body's subtle sensitivity to provide insulin in anticipation of meals. That leaves even the most compliant patients with wild swings in blood glucose that heighten long-term risks of heart disease, kidney failure, and nerve damage.Scientists have been working for a long time to replace natural insulin production with islet cell transplants. But there has always been one obstacle: rejection. The immune system is programmed to recognize donor cells as foreign and destroy them. To avoid this, recipients of transplants have to take immunosuppressive drugs for the rest of their lives. The drugs are effective, but they expose patients to infections, cancer, and organ injury—a trade-off that has kept cell transplantation from becoming mainstream.Insulin Production Without Immune SuppressionFor this new patient, who was diagnosed with type 1 diabetes at the age of 5, a healthy donor islet cells were given. Rather than injected into the pancreas, the cells were given through a series of injections into the muscle of his forearm. This made it easier for doctors to check on the graft and lower surgical risks.During the 12-week period, the transplanted cells started secreting insulin when there were high levels of glucose, like after meals. Most significantly, the patient did not need any immunosuppressant medications. His immune system merely left the cells alone—a feat that had never previously been achieved in humans.What Role CRISPR Gene Editing Play?The breakthrough was dependent on genetic engineering. Scientists applied the CRISPR gene-editing mechanism to make three critical modifications to the cells before they were transplanted:Diminishing immune "flags": Two edits reduced amounts of antigens that T cells typically employ to recognize foreign cells.Augmenting defense with CD47: The third edit boosted levels of CD47, a protein assigned the codename "don't eat me" signal, which deters natural killer cells and macrophages from targeting.Surprisingly, not every cell got the full complement of edits. The unedited ones were rapidly killed by the immune system. The partially edited cells survived a bit longer but were eventually rejected. Only the fully edited cells persisted—and they were the ones that achieved the successful production of insulin. This natural experiment within the body of the patient proved that the three-edit approach was the solution.How This Means Future of Diabetes Treatment Is Closer Than Ever?Even though the patient was given a modest amount of the engineered cells and still needs daily insulin, the outcome is a proof of concept that cell transplants are possible without immunosuppression. That in itself is a game changer.If additional research verifies the longevity and safety of this method, it may drastically increase access to islet cell transplantation. Patients would be able to obtain more stable blood sugar levels, lowering complications and enhancing quality of life. Larger grafts or multiple transplants over time may even render insulin treatment obsolete.The breakthrough follows a wave of experimental treatments for type 1 diabetes. In 2022, a woman in China underwent insulin-producing cells derived from her own stem cells, which made her able to sustain stable blood glucose without injections for months. Gene-edited islet cells have also produced encouraging results in animal trials.