1921-2021: From insulin discovery to islet transplantation in type 1 diabetes

One century after the discovery of insulin, the French Health regulations have just authorized the reimbursement for islet transplantation. Intraportal islet allotransplantation from a pancreatic donor is indicated in patients with type 1 diabetes (T1D) complicated with lability or hypoglycemia unawareness, or in case of a functioning kidney graft; islet auto-transplantation may be indicated after pancreatic surgery. Compared with insulin even administered in closed-loop pumps, the specificity of islet allotransplantation is the restoration of C-peptide secretion. Long-term insulin-independence is observed when the engrafted islet mass is sufficient, at the cost of immunosuppression. Fewer low-glucose events and less glucose variability, are observed even with minimal functional islet graft, after islet transplantation as at onset of T1D, when a residual C-peptide secretion is maintained, an objective currently approached with less aggressive immuno-modulating therapies than in the past. Therefore, restoration or preservation of endogen insulin secretion is an important goal, allowing to maintain a long-term glucose balance with more than 70% of time in range 3.9-10 mmol/L and less than 3% of time < 3.9 mmol/L, thus reducing the occurrence of diabetic complications. In the clinical setting, - the preservation of C-peptide at early stage of T1D, - the use of technological ressources (multi-injections, sensors, insulin pump, closed-loop systems) at later stages, - and islet transplantation when hypoglycemia awareness becomes impaired are complementary for a personalized care all along the life of T1D patients. (C) 2021 Published by Elsevier Masson SAS.

Automated summary

Islet transplantation, authorized for reimbursement in France, offers a specific restoration of C-peptide secretion for type 1 diabetes patients. Long-term insulin independence can be achieved with sufficient islet engraftment, reducing the occurrence of diabetic complications and improving glucose control. Personalized care throughout the life of T1D patients may involve preserving C-peptide early on, utilizing technological resources later, and considering islet transplantation when hypoglycemia awareness declines.