Heterogeneity of human pancreatic islet isolation around Europe: Results of a survey study

Background. Europe is currently the most active region in the field of pancreatic islet transplantation, and many of the leading
groups are actually achieving similar good outcomes. Further collaborative advances in the field require the standardization
of islet cell product isolation processes, and this work aimed to identify differences in the human pancreatic islet isolation
processes within European countries. Methods. A web-based questionnaire about critical steps, including donor selection,
pancreas processing, pancreas perfusion and digestion, islet counting and culture, islet quality evaluation, microbiological evaluation,
and release criteria of the product, was completed by isolation facilities participating at the Ninth International European
Pancreas and Islet Transplant Association (EPITA) Workshop on Islet-Beta Cell Replacement in Milan. Results. Eleven islet
isolation facilities completed the questionnaire. The facilities reported 445 and 53 islet isolations per year over the last 3 years
from deceased organ donors and pancreatectomized patients, respectively. This activity resulted in 120 and 40 infusions
per year in allograft and autograft recipients, respectively. Differences among facilities emerged in donor selection (age, cold
ischemia time, intensive care unit length, amylase concentration), pancreas procurement, isolation procedures (brand and concentration
of collagenase, additive, maximum acceptable digestion time), quality evaluation, and release criteria for transplantation
(glucose-stimulated insulin secretion tests, islet numbers, and purity). Moreover, even when a high concordance about the
relevance of one parameter was evident, thresholds for the acceptance were different among facilities. Conclusions. The
result highlighted the presence of a heterogeneity in the islet cell product process and product release criteria.