The Importance of Tryptic-like Activity in Purified Enzyme Blends for Efficient Islet Isolation
| Autor: | Annika Tibell, Kaija Salmela, M. Felldin, Daniel Brandhorst, Olle Korsgren, Heide Brandhorst, Andrew S. Friberg, Aksel Foss, Gunnar Tufveson, Helena H. Andersson, Torbjörn Lundgren |
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| Rok vydání: | 2009 |
| Předmět: |
Male
medicine.medical_specialty Cell Survival Transplantation Heterologous Islets of Langerhans Transplantation Thermolysin Mice Nude Heterologous Cell Separation Biology Diabetes Mellitus Experimental Islets of Langerhans Mice Insulin-Secreting Cells Internal medicine medicine Animals Humans Insulin Trypsin Collagenases chemistry.chemical_classification Transplantation geography geography.geographical_feature_category Graft Survival Biological activity Middle Aged Islet Isolation (microbiology) Tissue Donors Rats Human pancreas Endocrinology Enzyme Biochemistry chemistry Rats Inbred Lew Collagenase Female medicine.drug |
| Zdroj: | Transplantation. 87:370-375 |
| ISSN: | 0041-1337 |
| DOI: | 10.1097/tp.0b013e31819499f0 |
| Popis: | 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. |
| Databáze: | OpenAIRE |
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