Donor and Isolation Variables Predicting Human Islet Isolation Success

Abstract

Recent advances in the fields of islet transplantation and in vitro islet cell expansion place a renewed emphasis on the optimization of islet isolation from cadaveric human donor organs. We retrospectively analyzed 171 islet isolations to identify variables that predict islet yield and isolation success. Cadaveric human donor pancreata were procured and processed according to established protocols. Donor-, procurement-, and isolation-related variables were analyzed for correlation with islet yield and isolation success (> or =250,000 islet equivalents). Univariate analysis suggested correlations between islet yield and donor age (P<0.005), body surface area (P<0.005), duration of enzymatic digestion (P<0.001), and pancreatic beta-cell volume (P<0.05). Donor sex (P<0.01), procurement team (P<0.05), and peridigestion serine protease inhibition (P<0.05) affected islet yield, whereas enzyme lot (P<0.01) and pancreatic fatty infiltration (P<0.05) influenced isolation success. By logistic regression, donor sex and age, and duration of enzymatic digestion could predict a successful isolation with 72% accuracy. The use of Liberase CI improved islet yield (P<0.05) in young donors (< or =25 years). While donor-related variables are useful in predicting islet yield, these are likely surrogates for pancreatic beta-cell volume. Enzyme lot, and the associated duration of enzymatic digestion (P<0.05), appears to be key determinants of isolation success.