Human Pancreatic Islet Isolation: Part I: Digestion and Collection of Pancreatic Tissue
Summary
Achieving high quality and appropriate quantity of human islets is one of the prominent prerequisites for successful islet transplantation. In this video, we describe step by step the procedures for human pancreatic islet isolation (part I: digestion and collection of pancreatic tissue) using a modified automated method.
Abstract
Management of Type 1 diabetes is burdensome, both to the individual and society, costing over 100 billion dollars annually. Despite the widespread use of glucose monitoring and new insulin formulations, many individuals still develop devastating secondary complications. Pancreatic islet transplantation can restore near normal glucose control in diabetic patients 1, without the risk of serious hypoglycemic episodes that are associated with intensive insulin therapy. Providing sufficient islet mass is important for successful islet transplantation. However, donor characteristic, organ procurement and preservation affect the isolation outcome 2. At University of Illinois at Chicago (UIC) we have developed a successful isolation protocol with an improved purification gradient 3. The program started in January 2004, and more than 300 isolations were performed up to November 2008. The pancreata were sent in cold preservation solutions (UW, University of Wisconsin or HTK, Histidine-Tryptophan Ketoglutarate) 4-7 to the Cell Isolation Laboratory at UIC for islet isolation. Pancreatic islets were isolated using the UIC method, which is a modified version of the method originally described by Ricordi et al 8. Briefly, after cleaning the pancreas from the surrounding tissue, it was perfused with enzyme solution (Serva Collagenase + Neutral Protease or Sigma V enzyme). The distended pancreas was then transferred to the Ricordi digestion chamber, connected to a modified, closed circulation tubing system, and warmed up to 37°C. During the digestion, the chamber was shaken gently. Samples were taken continuously to monitor the digestion progress. Once free islets were detected under the microscope, the digestion was stopped by flushing cold (4°C) RPMI dilution solution (Mediatech, Herndon, VA) into the circulation system to dilute the enzyme. After being collected and washed in M199 media supplemented with human albumin, the tissue was sampled for pre-purification count and incubated with UW solution before purification. Purification process will be described in Part II: Purification and Culture of Human Islets.
Protocol
1. Facility setup Human islet isolation is a time sensitive procedure that involves teamwork, and hence, four individuals are needed to conduct this procedure. The team is lead by the surgeon, who dissects and cannulates the pancreas. The islet isolation begins the minute the team enters the UIC islet isolation facility. Team members ensure that all necessary instrumentation, like the centrifuge, is checked and turned on. They also make sure to sanitize all hoods and surfaces. Two people …
Discussion
There are a variety of factors affecting the isolation outcome 9,10. Among them, digestion of the pancreatic tissue plays a prominent role. Based on our own human islet isolation experience, we summarized following critical points, which could potentially influence the islet yield and quality.
- The digestion time is different when different types of enzymes are utilized.
- As soon as 40-50% of the islets completely separated from acinar tissue, the digestion should be stopped immediately by adding dilu…
Acknowledgements
Supported by funding from the University of Illinois at Chicago as well as Islet Cell Resource Center NIH grant (RFA-RR 05-003), the Christopher Foundation, the Efroymson Foundation, and the Tellabs Foundation.
Materials
| Material Name | Tipo | Company | Catalogue Number | Comment |
|---|---|---|---|---|
| Ice Slush Machine | equipment | Taylor Company | K4036546 | make sterile ice |
| Centrifuge | equipment | Beckman Coulter | 424803 | |
| MZ6 Inverted Microscopy TLBD4.1 | equipment | Leica Diagnostic Instrument Co | 4103 | |
| Cell Culture Dish with 2 mm Grid | equipment | Nunc Brand Products | 174926 | islet counting |
| Digital Water Bath EX7 | equipment | NesLab | 105361058 | |
| Thermometer | equipment | IBI:IR | 60444 | |
| MonoBloc Balance AB 104-S | equipment | Metler Toledo | 1119430864 | measure pancreas weight |
| MasterFlex II Speed Controller | equipment | Cole Parmer Instrument Co | J00006445 | adjust flow speed during degestion |
| Digital Sight DS L1 | equipment | Nikon | 217267 | |
| Perfusion Unit | equipment | Custom Made/Swiss | n/a | |
| Cooler for perfusion unit | equipment | Fisher Scientific | 3013P | |
| Ricordi Chamber | equipment | University of Miami | n/a | |
| RPMI dilution solution | reagent | Mediatech Inc | 99783024 | |
| University of Wisconcin (UW) solution | reagent | DURAMED | 1000-46-06 | |
| Hank’s Buffered Salt Solution (HBSS) | reagent | Mediatech Inc | 99-597-CM | |
| 25% Human Albumin | reagent | GRIFOLS | NDC 61953-0002-2 | |
| M199 media (wash solution) | reagent | Mediatech Inc | 99-784-CM | |
| Collagenase NB1 GMP grade | reagent | SERVA Electrophoresis | N0002937 | |
| Neutral Protease NB1 GMP grade | reagent | SERVA Electrophoresis | N0002936 | |
| Betadine | reagent | Cardinal Health | 29906-004 | |
| Cefazolin | reagent | West-Ward Pharmaceutical | NDC 0143-9924-90 | |
| Dithizone | reagent | Sigma | D5130 |
Riferimenti
- Shapiro, A. M., et al. Islet transplantation in seven patients with type 1 diabetes mellitus using a glucocorticoid-free immunosuppressive regimen. N Engl J Med. 343, 230-238 (2000).
- Nano, R., et al. Islet isolation for allotransplantation: variables associated with successful islet yield and graft function. Diabetologia. 48, 906-912 (2005).
- Barbaro, B., et al. Improved human pancreatic islet purification with the refined UIC-UB density gradient. Transplantation. 84, 1200-1203 (2007).
- Lakey, J. R., Rajotte, R. V., Warnock, G. L., Kneteman, N. M. Human pancreas preservation prior to islet isolation. Cold ischemic tolerance. Transplantation. 59, 689-694 (1995).
- Fridell, J. A., et al. Comparison of histidine-tryptophan-ketoglutarate solution and University of Wisconsin solution for organ preservation in clinical pancreas transplantation. Transplantation. 77, 1304-1306 (2004).
- Potdar, S., et al. Initial experience using histidine-tryptophan-ketoglutarate solution in clinical pancreas transplantation. Clin Transplant. 18, 661-665 (2004).
- Salehi, P., et al. Human islet isolation outcomes from pancreata preserved with Histidine-Tryptophan Ketoglutarate versus University of Wisconsin solution. Transplantation. 82, 983-985 (2006).
- Ricordi, C., Lacy, P. E., Scharp, D. W. Automated islet isolation from human pancreas. Diabetes. 38, 140-142 (1989).
- Hanley, S. C., Paraskevas, S., Rosenberg, L. Donor and isolation variables predicting human islet isolation success. Transplantation. 85, 950-955 (2008).
- Toso, C., et al. Factors affecting human islet of Langerhans isolation yields. Transplant Proc. 34, 826-827 (2002).
Tags
Human Pancreatic Islet IsolationDigestionCollectionType 1 DiabetesGlucose ControlInsulin TherapyIslet TransplantationDonor CharacteristicsOrgan ProcurementPreservationIsolation ProtocolPurification GradientCold Preservation SolutionsCell Isolation LaboratoryUIC MethodRicordi Et Al MethodEnzyme Solution
Citazione di questo articolo
Qi, M., Barbaro, B., Wang, S., Wang, Y., Hansen, M., Oberholzer, J. Human Pancreatic Islet Isolation: Part I: Digestion and Collection of Pancreatic Tissue. J. Vis. Exp. (27), e1125, doi:10.3791/1125 (2009).