Isolation of functional human islets from pancreatectomy remnants: Determinants of yield and functionality

Human pancreatic islets are essential for studies in β-cell biology, cell transplantation, and tissue engineering, yet access to viable human islets remains limited because conventional isolation protocols primarily rely on whole pancreases from deceased donors. Surgical pancreatectomy specimens may represent an accessible alternative source, but factors influencing successful isolation and functional preservation remain poorly defined. In this study, we evaluated a standardized method for isolating human islets from pancreatic tissue obtained from surgical pancreatectomy specimens and investigated patient-, specimen-, and surgery-related factors affecting islet yield and functionality. Between March and October 2024, 50 consecutive islet isolations were performed from pancreatic specimens obtained during surgical resections. Following enzymatic digestion, tissue fractions were cultured for 24 h before handpicking of morphologically intact islets. Islet yield was quantified as islet equivalents (IEQ), and functional integrity was assessed by glucose-stimulated insulin secretion assays on culture days 1, 3, and 5. A mean yield of 6690 IEQ/g pancreatic tissue was obtained (range 0-56,500 IEQ/g). Exploratory analyses suggested potential associations between islet yield and factors such as younger patient age, shorter surgical duration, and preserved pancreatic parenchyma. However, these findings should be interpreted cautiously given the variability of the specimens and the exploratory design of the study. These findings support the feasibility of using surgical pancreatectomy specimens as an accessible source of functional human islets for experimental and translational research.