THE CORRELATION BETWEEN DONOR CHARACTERISTICS AND THE SUCCESS OF HUMAN ISLET ISOLATION

Clinical islet allotransplantation is dependent on the ability to achi eve a high yield and purity of islets isolated from human cadaver panc reas donors. The aim of this study was to determine the factors influe ncing the pancreas prior to islet isolation that may alter yield and p urity. The results of 50 consecutive islet isolations from cadaver don or human pancreati at the University of Chicago Medical Center from De cember 1991 to April 1993 were analyzed. All pancreati were first offe red for whole pancreas transplantation before being considered for isl et isolation. Human pancreatic islet isolation was accomplished by a m odified automated method. Some islet isolations resulted in a high isl et yield but low islet purity. Other resulted in well-purified islets, but a low yield. Arbitrarily, successful islet isolation is defined a s that yielding over 250,000 islet equivalents (EQN) with a purity of at least 80%. The success rate of human pancreatic islet isolation was 70%. The mean final islet yield obtained from these 50 pancreati was 300,000+/-131,000 islet EQN. The mean purity of the final preparation was 73%+/-25%. By univariate analysis, five factors were found to affe ct significantly the yield, purity, or overall success rate of islet i solation: organ cold ischemic time, donor age, donor plasma glucose le vels, donor body weight, and cause of donor death. Even when islet iso lation was successful, the function of islets from hyperglycemic and o lder donors appear to be impaired both in vitro and in vivo. These res ults suggest that islet yield and purity are affected by multiple dono r-related factors. Even when adequate yield and purity are obtained, i slet function is also dependent on donor variables.