The importance of tryptic-like activity in purified enzyme blends for efficient islet isolation
2009 (English)In: Transplantation, ISSN 0041-1337, E-ISSN 1534-6080, Vol. 87, no 3, 370-5 p.Article in journal (Refereed) Published
BACKGROUND: The isolation of islets from the human pancreas critically depends on an efficient enzyme blend. Previous studies have solely focused on the presence of collagenase and neutral protease/thermolysin. Despite improved characterization of these components, the lot-related variability in efficacy still persists suggesting that additional so far disregarded enzymes are required for efficient islet cleavage. METHODS: Varying activities of a tryptic-like enzyme were identified within collagenase NB1 lots, which were selected according to a matched ratio between tryptic-like and collagenase activity (TLA-ratio). Rat and human pancreata were processed with current standard procedures. RESULTS: Increasing the TLA-ratio from 1.3% to 10% reduced pancreas dissociation time in rats by 50% without affecting islet yield, viability, or posttransplant function in diabetic nude mice. Enhancing the TLA-ratio from 1.3% to 12.6% for human pancreas processing resulted in a significant reduction of recirculation time and increased incrementally human islet yield without affecting purity, in vitro function or recovery after culture. Optimized pancreas digestion correlated with a higher percentage of islet preparations fulfilling quality criteria for clinical transplantation. CONCLUSIONS: We conclude that TLA is an effective component that should be included in moderate amounts in enzyme blends for human islet isolation to optimize the efficiency and minimize the lot-related variability.
Place, publisher, year, edition, pages
2009. Vol. 87, no 3, 370-5 p.
human islet transplantation, human islet isolation, collagenase, enzymes
Research subject Medical Science
IdentifiersURN: urn:nbn:se:uu:diva-103604DOI: 10.1097/TP.0b013e31819499f0ISI: 000263397400010PubMedID: 19202441OAI: oai:DiVA.org:uu-103604DiVA: diva2:218536