Type 1 diabetes is a case of mistaken identity. The immune system decides the cells in the pancreas that make insulin are no good, and thus destroys them. You can replace those cells with donated ones and surgeons have been doing so for years, but the immune system takes the same view of the replacements.
So recipients spend the rest of their lives on drugs that suppress their immune system, swapping a manageable disease for a permanent vulnerability to everything else. Not everyone considers that a bargain.
The alternative is to leave the immune system alone and disguise the cells instead. Researchers did just that, using CRISPR to make three edits to donor cells: two that strip away the surface proteins the immune system reads like a barcode, and one that boosts a protein called CD47, which functions as a note reading "nothing to see here".
The cells went into a 42-year-old man's forearm in December 2024, with no immunosuppressants of any kind. Fourteen months later, they are still there, producing insulin, and producing more of it after meals. His immune system has never noticed them.
The caveats are substantial: one patient, a deliberately small dose and he still injects insulin daily. What has been shown is that the disguise holds, not that the disease has been treated. There is also something faintly unnerving about the method. CD47 is the same signal tumours use to avoid being eaten by the immune system, so making transplanted cells invisible means borrowing a technique from cancer. Fine, presumably, so long as the cells behave.
It is also why fourteen months of clean follow-up really is remarkable.
Artists impression of the recipient
🧐 What's in it for me? The disguise doesn’t seem to care what it's hiding and so the same trick applies to any transplanted cell. This puts a satisfying and potentially extremely lucrative dent in the central problem of transplant medicine.
💵 Out of the Lab: A functional cure for type 1 diabetes would be a rare thing in pharma, a product that eliminates its own recurring revenue, and the companies chasing it are mostly not the ones currently selling insulin (‘shock’).
Sana Biotechnology owns the hypoimmune platform behind this result and is moving to a stem cell derived version, which removes the awkward dependence on deceased donors.
Vertex is furthest along with lab-grown islet cells and has produced more dramatic glucose results, but its patients still take immunosuppressants. The two approaches are solving opposite halves of the same problem.
Aspect Biosystems, a Vancouver startup bioprinting implantable tissue, is partnered with Novo Nordisk on exactly this.
Until next time.
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