Curing Type 1 Diabetes Without Lifelong Immunosuppression

Think of blood sugar as the water level in a tank, kept steady by an automatic valve. Intype 1 diabetes the body’s own immune system destroys the valve, so the level swingsdangerously and the person must dose insulin by hand for life. The real fix is to install anew valve — new insulin-making cells — and this now works well enough that most peoplein a recent trial stopped needing injected insulin. The catch is that the immune systemattacks any new cells, so patients must take powerful drugs that switch off immunedefenses, which brings its own dangers. The frontier, and the subject of this paper, is anew valve the immune system simply does not see: insulin-making cells engineered tohide their identity tags. In 2025 this was shown to work in a person for the first time, withno immune-suppressing drugs at all — though the dose was small on purpose, as a firsttest. This paper explains why that is the right target, gives a simple mathematical modelanyone can run, and is honest about what still has to be proven.