51
|
Goto M, Eich TM, Felldin M, Foss A, Källen R, Salmela K, Tibell A, Tufveson G, Fujimori K, Engkvist M, Korsgren O. Refinement of the automated method for human islet isolation and presentation of a closed system for in vitro islet culture. Transplantation 2004; 78:1367-75. [PMID: 15548977 DOI: 10.1097/01.tp.0000140882.53773.dc] [Citation(s) in RCA: 175] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND The procedure of human islet isolation needs further optimization and standardization. Here, we describe techniques to enhance enzymatic digestion and minimize mechanical forces during the digestion process. The isolation protocol has also been modified to meet current GMP (cGMP) standards. Moreover, the impact of donor- and process-related factors was correlated to the use of islets for clinical transplantation. METHODS One hundred twelve standardized consecutive islet isolations were evaluated. Metyltioninklorid and indermil (topical tissue adhesive) were applied to detect leakage of collagenase injected and to repair the damaged pancreatic glands. The effects of dye and glue were evaluated in terms of islet yield, islet function using the perifusion assay, and success rate of the isolation. To analyze key factors for successful isolations, both univariate and multivariate regression analysis were performed. RESULTS Both Metyltioninklorid and Indermil were effective to prevent leakage of enzyme solutions from the pancreatic glands. Both islet yield and success rate were higher when these tools were applied (4,516.1+/-543.0 vs. 3,447.7+/-323.5, P=0.02; 50.0% vs. 21.3%, P=0.02, respectively). No adverse effects on islet function or collagenase activity were observed. Multivariate regression analysis identified the maximal recorded amylase >100 U/L (P=0.026), BMI (P=0.03), and the use of catecholamine (P=0.04) as crucial donor-related factors. In addition, cold ischemia time (P=0.005), the dissection procedure using whole glands with duodenum (P=0.02), and the local procurement team (P=0.03) were identified as crucial isolation-related variables. CONCLUSIONS A standardized technique of islet isolation is presented applying novel means to improve enzymatic digestion and to meet cGMP standards.
Collapse
Affiliation(s)
- Masafumi Goto
- Department of Radiology, Oncology and Clinical Immunology, Division of clinical Immunology, University Hospital, Uppsala, Sweden.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
52
|
Tsujimura T, Kuroda Y, Avila JG, Kin T, Oberholzer J, Shapiro AMJ, Lakey JRT. Influence of pancreas preservation on human islet isolation outcomes: impact of the two-layer method. Transplantation 2004; 78:96-100. [PMID: 15257045 DOI: 10.1097/01.tp.0000133515.37892.d5] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Human pancreas preservation for islet transplantation holds additional challenges and considerations compared with whole pancreas transplantation. The purpose of this study was to clarify the limitations of the University of Wisconsin (UW) solution and the potentials of the two-layer method (TLM) for pancreas preservation before human islet isolation. METHODS We retrospectively evaluated human islet isolation records between January 2001 and February 2003. One hundred forty-two human pancreata were procured from cadaveric donors and preserved by means of the UW solution (n=112) or TLM (n=30). Human islet isolations were performed using a standard protocol and assessed by islet recovery and in vitro function of islets. RESULTS Eight to ten hours of cold ischemia in the UW solution is a critical point for successful islet isolations. It is difficult to recover a sufficient number of viable islets for transplantation from human pancreata with more than 10 hours of cold storage in the UW solution. The overall islet recovery in the TLM group was significantly higher than in the UW group. With 10 to 16 hours of cold storage, the success rates of islet isolations remained at 62% in the TLM group but decreased to 22% in the UW group. Transplanted islets in the TLM group worked well in the recipients. CONCLUSIONS There are time limitations for using the UW solution for pancreas preservation before human islet isolation. The TLM is a potential method to prolong the optimal cold storage time for successful islet isolations.
Collapse
Affiliation(s)
- Toshiaki Tsujimura
- Surgical-Medical Research Institute, University of Alberta, Edmonton, Canada
| | | | | | | | | | | | | |
Collapse
|
53
|
Huang GC, Zhao M, Jones P, Persaud S, Ramracheya R, Löbner K, Christie MR, Banga JP, Peakman M, Sirinivsan P, Rela M, Heaton N, Amiel S. The development of new density gradient media for purifying human islets and islet-quality assessments. Transplantation 2004; 77:143-5. [PMID: 14724452 DOI: 10.1097/01.tp.0000100401.62912.b2] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Successful islet transplantation is dependent on the quality and quantity of islets infused. Islets are purified on density gradients, but procedures currently used have limited capacity for pancreatic digests, islet yield, and viability. We aimed to improve islet purification with a modified gradient medium. Biocoll was diluted in University of Wisconsin solution to create linear density gradients of 1.065 to 1.095 g/mL. Properties of islets purified from 22 human pancreas digests with modified medium were compared with 15 preparations using standard medium. The modification increased the capacity of gradients for pancreatic digests from 20 to 60 mL, islet yield increased from 218,000 to 435,318 per isolation, and viability increased from 65.4% to 92.1%. Islet fractions contained greater than 95% of recovered insulin. Islets showed good physiologic responses to secretagogues and restored normoglycemia in streptozotocin-induced diabetic severe combined immunodeficiency disease mice. The new medium enhances yield, purity, and viability of human islet preparations for clinical islet transplantation.
Collapse
Affiliation(s)
- Guo Cai Huang
- Department of Diabetes, Endocrinology and Internal Medicine, King's College GKT Medical School, London, UK.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
54
|
Tsujimura T, Kuroda Y, Churchill TA, Avila JG, Kin T, Shapiro AMJ, Lakey JRT. Short-term storage of the ischemically damaged human pancreas by the two-layer method prior to islet isolation. Cell Transplant 2004; 13:67-73. [PMID: 15040607 DOI: 10.3727/000000004772664914] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A two-layer cold storage method (TLM) allows sufficient oxygen delivery to pancreata during preservation and resuscitates the viability of ischemically damaged pancreata in the canine pancreas transplant model. In this study, we applied a short-term preservation of the TLM to human pancreata after prolonged cold ischemia prior to islet isolation, and investigated the mechanisms of resuscitation of the ischemically damaged human pancreas by the TLM. Human pancreata were procured from cadaveric donors and preserved by the TLM for 3.2 +/- 0.5 h after 11.1 +/- 0.9 h of cold storage in UW (TLM group), or by cold UW alone for 11.0 +/- 0.3 h (UW group). Islet isolations of all pancreata were performed using the Edmonton protocol. Islet recovery and in vitro functional viability of isolated islets were significantly increased in the TLM group compared with the UW group. According to the criteria of the Edmonton protocol, 10/14 cases (71%) in the TLM group were transplanted to patients with type I diabetes mellitus compared with only 5/21 cases (24%) in the UW group. In the metabolic assessment of human pancreata, levels of energetic parameters (ATP, total adenylates, and energy charge) were significantly increased, and malondialdehyde (MDA) levels were significantly decreased after the TLM preservation. There was no observable change in the incidence or degree of mitochondrial injury after the TLM preservation. Additional short-term storage by the TLM resuscitates the ischemically damaged human pancreas by regenerating the energetic status and prevents further damage by oxidative stress, ultimately leading to improvements of islet recovery and in vitro function. Use of the TLM following prolonged storage in UW provides an excellent adjunctive protocol for treating human pancreata for the rigors of the islet isolation process.
Collapse
Affiliation(s)
- Toshiaki Tsujimura
- Surgical-Medical Research Institute, Department of Surgery, University of Alberta, Edmonton, Alberta T6G2N8, Canada
| | | | | | | | | | | | | |
Collapse
|
55
|
Rose NL, Palcic MM, Shapiro AMJ, Lakey JRT. An evaluation of endogenous pancreatic enzyme levels following enzymatic digestion. Transplant Proc 2003; 35:2458-60. [PMID: 14611985 DOI: 10.1016/j.transproceed.2003.09.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Human islet isolation consists of a digestion phase, dilution phase, and purification phase. Recent evidence suggests that inconsistencies in islet yields are attributed to the activation of endogenous enzymes of the donor pancreas during the digestion phase. Therefore, following the digestion phase, it is important to inhibit these enzymes by the addition of an inhibitor to the dilution phase. In this study, we report the endogenous pancreatic enzyme levels after the purification phase and the effects of potential inhibitors on the proteases of interest. Results at the end of the purification phase indicated that chymotrypsin retained approximately 20% of the activity observed after the digestion phase, whereas trypsin, elastase, and collagenase retained approximately 2.5%, 2%, and 3.5% of the activity, respectively, demonstrating that added inhibitors are not fully effective. Potential enzyme inhibitors, human albumin, fetal calf serum, and aprotinin, were incubated with trypsin, chymotrypsin, elastase, and collagenase and assayed for activity. Fetal calf serum and aprotinin showed strong inhibitory actions toward trypsin and chymotrypsin. Aprotinin completely inhibited the tryptic activity; however, it did not inhibit human chymotrypsin or elastase activity. Human albumin showed minimal inhibition and was shown to act as a competitive inhibitor. This study clearly demonstrates that low amounts of endogenous pancreatic enzymes remain active at the end of the human islet isolation procedure and that the added inhibitors at the dilution are not fully effective at inhibiting the enzymes.
Collapse
Affiliation(s)
- N L Rose
- Department of Surgery, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | |
Collapse
|
56
|
Rose NL, Palcic MM, Shapiro AMJ, Lakey JRT. An evaluation of the activation of endogenous pancreatic enzymes during human islet isolations. Transplant Proc 2003; 35:2455-7. [PMID: 14611984 DOI: 10.1016/j.transproceed.2003.08.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Despite advances in human islet isolations, there remain inconsistencies in human islet yield and viability after collagenase digestion. It has been suggested that trypsin may contribute to the proteolysis of collagenase and the destruction of islet cells, or possibly exert indirect effects on the pancreas by activating other endogenous serine proenzymes. This study evaluated the effects of serine proteases on collagenase activity and profiled the kinetics of serine protease activity throughout human islet isolations with and without addition of Pefabloc, a serine protease inhibitor. Cadaveric pancreases were perfused in the presence (n = 12) and absence of Pefabloc (0.4 mmole; n = 8). Samples were collected before and throughout the digestion process and were assayed for trypsin, chymotrypsin, and elastase activity. A study of the enzyme kinetics of serine proteases throughout human islet isolations showed an increase in activity levels throughout the digestion period. There was a significant difference in the chymotrypsin (1342 +/- 503 and 384 +/- 71 units) and elastase (7.94 +/- 1.1 and 2.761 +/- 0.69 units) levels between the control and Pefabloc-supplemented isolations, respectively. There was no significance difference noted among the trypsin (88 +/- 27 and 54 +/- 18 units) levels between the control and Pefabloc-supplemented isolations, respectively. This demonstrates that serine proteases are effectively inhibited by Pefabloc during the islet isolation process. These data show that the presence of serine proteases may likely damage the islets upon prolonged digestion of the pancreatic tissue.
Collapse
Affiliation(s)
- N L Rose
- Department of Surgery, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | |
Collapse
|
57
|
Balamurugan AN, Chang Y, Fung JJ, Trucco M, Bottino R. Flexible management of enzymatic digestion improves human islet isolation outcome from sub-optimal donor pancreata. Am J Transplant 2003; 3:1135-42. [PMID: 12919094 DOI: 10.1046/j.1600-6143.2003.00184.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Worldwide growing interest in reproducing the result of the Edmonton protocol in islet transplantation trials poses the problem of paucity of donors to supply sufficient amount of islets for clinical use. Improved outcomes include finding better ways to obtain higher yields from every donor organ processed and the possibility of extending islet isolation processing to glands of suboptimal quality. In order to optimize enzymatic digestion of marginal donor organs, we have modified the technique of tissue collection following enzymatic digestion of human pancreatic organs, allowing for reduced time of exposure of free islets to warm Liberase trade mark solution. Our results indicate that better controlled exposure to enzyme yields: (i) higher islet numbers; (ii) complete dissociation of all parts of pancreatic tissue; (iii) successful islet harvest from organs otherwise excluded. We also show that by limiting the exposure of free islets to enzyme solution, islet fragmentation and loss of insulin content are reduced. We further support evidence that enzymatic digestion may contribute to impairment of insulin secretory capacity of the islets in vitro during culture.
Collapse
Affiliation(s)
- A N Balamurugan
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
| | | | | | | | | |
Collapse
|
58
|
Kinasiewicz A, Fiedor P. Amylase levels in preservation solutions as a marker of exocrine tissue injury and as a prognostic factor for pancreatic islet isolation. Transplant Proc 2003; 35:2345-6. [PMID: 14529937 DOI: 10.1016/s0041-1345(03)00795-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Occurrence of primary graft nonfunction of pancreatic islets demands research for new methods of organ preservation during cold ischemia conditions. Digestive enzymes released during preservation injure the islets for subsequent rewarming and islet isolation processes. The aim of our study was to assess the amylase level in preservation solution as a marker of exocrine tissue injury, allowing the prognosis of islet yield and viability. The experiments undertaken on rats used three commercially available preservation solutions: ViaSpan (UW); Custodiol (HTK); and Euro-Collins (EC). After 180 minutes of cold ischemia, the highest islet recovery was observed among pancreata stored in UW solution (508 +/- 139 vs HTK 344 +/- 103; P <.05 vs EC 322 +/- 113; P <.05). These islets also revealed the highest insulin stimulation index in glucose static tests (1.19 +/- 0.30 vs HTK, 0.87 +/- 0.43; P <.01, vs EC.25 +/-.06; P <.001). The highest amylase level in the preservation solution was associated with a decreased yield of islets during the isolation process and lowest insulin stimulation index (increasing 139 +/- 18% for EC, 108 +/- 12% for HTK; P <.05 vs 87 +/- 10% for UW; P <.05). Our data strongly suggest, that the dynamic of amylase release during pancreas preservation at 4 degrees C correlates with a reduced number and viability of isolated islets. These results suggest that measurement of amylase levels after pancreas preservation may have potential clinical application as a marker to evaluate pancreatic tissue injury.
Collapse
Affiliation(s)
- A Kinasiewicz
- Department of General and Transplantation Surgery, Medical University of Warsaw, Warsaw, Poland
| | | |
Collapse
|
59
|
|
60
|
Abstract
INTRODUCTION Recent evidence has suggested that inconsistencies in human islet yield and viability after collagenase digestion is attributed to the activation of endogenous enzymes of the cadaveric donor pancreas. A study of the enzyme kinetics of serine proteases throughout human islet isolations showed a significant increase in activity levels throughout the digestion period. Following the digestion, it is important to further inhibit these enzymes by the addition of an inhibitor to the dilution media. AIM To report the levels of endogenous pancreatic enzymes remaining after human islet isolation and the effects of three potential enzyme inhibitors on the proteases. METHODOLOGY Human albumin, fetal calf serum, and the protease inhibitor aprotinin were incubated with the trypsin, chymotrypsin, elastase, and collagenase and were assayed for activity. RESULTS Results at the final stage indicated that chymotrypsin retained 21.0 +/- 7.5% (mean +/- SE; n = 20) of the activity observed at the conclusion of the enzymatic digestion phase of the isolation process, whereas trypsin, elastase, and collagenase retained 3.0 +/- 1.5%, 2.1 +/- 0.6%, and 3.9 +/- 0.9%, respectively. Fetal calf serum and aprotinin showed strong inhibitory effects against bovine pancreatic trypsin; however, they showed a weak inhibitory effect against elastase. Supplementation with aprotinin failed to inhibit human chymotrypsin and elastase. Human albumin showed minimal inhibition and was shown to serve only as a competitive inhibitor. No inhibition to collagenase was observed with human albumin, fetal calf serum, or aprotinin. CONCLUSIONS This study clearly demonstrates that low amounts of endogenous pancreatic enzymes remain active throughout the human islet isolation process and that the added inhibitors at the end of the isolation process are not fully effective at inhibiting the enzymes.
Collapse
Affiliation(s)
- Natisha L Rose
- Department of Surgery, Surgical-Medical Research Institute, University of Alberta, Edmonton, Alberta, Canada
| | | | | |
Collapse
|
61
|
Lögdberg L, Sgan SL, Larsen CP, Hillyer CD. Islet transplantation, stem cells, and transfusion medicine. Transfus Med Rev 2003; 17:95-109. [PMID: 12733103 DOI: 10.1053/tmrv.2003.50006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Despite the widespread use of exogenous insulin, morbidity and mortality caused by type 1 diabetes mellitus (DM) continue to place a significant burden on society, both in terms of human suffering and cost. The transplantation of vascularized pancreas, usually performed concurrently with renal transplantation, can cure type 1 DM, as shown by results in more than 15000 such transplants over about 30 years. Transplantation of isolated pancreatic islets, instead of the whole organ, however, offers an attractive alternative that minimizes surgery and its complications. Although islet transplantation initially met with only modest success (only about 9% insulin independence at 1 year posttransplant), recent changes in patient selection criteria, number and treatment of islets transplanted, and better immunosuppressive regimens dramatically improved the results; spawning widespread enthusiasm for islet transplantation. Despite this promise, organ/islet availability remains an important limitation to this technology. A solution to the problem of limited materials for transplantation may be in the use of stem/progenitor cells. This article reviews the background of the current enthusiasm for pancreatic islet cell transplantation, highlights future research trends in the field, and suggests that the new islet-related cellular therapies belong within the domain of transfusion medicine.
Collapse
Affiliation(s)
- Lennart Lögdberg
- Department of Pathology, The Carlos and Marguerite Mason Transplantation Biology Research Center, Emory University School of Medicine, Atlanta 30322, GA, USA.
| | | | | | | |
Collapse
|
62
|
Rose NL, Palcic MM, Helms LMH, Lakey JRT. Evaluation of Pefabloc as a serine protease inhibitor during human-islet isolation. Transplantation 2003; 75:462-6. [PMID: 12605110 DOI: 10.1097/01.tp.0000046537.47139.ce] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Recent evidence has suggested that inconsistencies in human-islet yields after collagenase digestion are attributed to the activation of endogenous enzymes of the cadaveric donor pancreas. Inhibition of protease activity by Pefabloc (0.4 mM; Roche Biochemicals Inc., Indianapolis, IN) has recently been shown to improve human-islet isolation after prolonged cold storage of the pancreas. In this study, we have hypothesized that this improvement was because of the inhibition of three key serine proteases. METHODS Twenty cadaveric pancreases were perfused in the presence (n=12) and absence (n=8) of Pefabloc added at the time of distention using a customized perfusion device. Samples were collected throughout the digestion process and were assayed for trypsin, chymotrypsin, elastase, and total protease activity. RESULTS In all cases, the enzyme activity levels remained lower in the presence of Pefabloc as compared with the control samples. There was significantly higher chymotrypsin and elastase activity in the control group, but not trypsin or total protease activity, from the time following loading of the enzyme onto the pancreas until the stopping of the enzymatic digestion phase (dilution). CONCLUSIONS Pefabloc was shown to be an effective protease inhibitor throughout the entire digestion process. Pefabloc supplementation did not significantly effect the dilution time or the islet yield in this study; however, these data show that serine proteases are effectively inhibited by Pefabloc during the clinical islet process.
Collapse
Affiliation(s)
- Natisha L Rose
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | |
Collapse
|
63
|
Matsumoto S, Rigley TH, Reems JA, Kuroda Y, Stevens RB. Improved islet yields from Macaca nemestrina and marginal human pancreata after two-layer method preservation and endogenous trypsin inhibition. Am J Transplant 2003; 3:53-63. [PMID: 12492711 DOI: 10.1034/j.1600-6143.2003.30110.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We tested whether two-layer method (TLM) pancreas preservation and trypsin inhibition (Pefabloc) during processing allows longer preservation while retaining or improving viable islet recovery. Non-marginal primate (Macaca nemestrina) and marginal human (ischemic or preservation-injured) pancreata were processed with a research-oriented pan technique (Seattle method). Organs were processed upon arrival (+/- Pefabloc), or after TLM or University of Wisconsin solution (UW) preservation (+ Pefabloc). Islet yield, viability, and function were assessed. Pefabloc increased M. nemestrina islet yields from 9696 +/- 1749 IE/g to 15 822 +/- 1332 IE/g (p < 0.01). Two-layer method preservation (< 6 h) further increased yields, to 23 769 +/- 2773 IE/g (vs. + Pefabloc; p < 0.01). Similarly, Pefabloc increased marginal human islet yields from 2473 +/- 472 IE/g to 4723 +/- 1006 IE/g (p < 0.04). This increase was maintained after lengthy TLM preservation (> 30 h; 4801 +/- 1066 IE/g). We also tested the applicability of TLM preservation (23.5 +/- 3.2 h) to the processing of marginal human pancreata by the Edmonton/Immune Tolerance Network clinical protocol. Islet yield and function approached published results of pancreata processed 4.8 +/- 0.8 h after organ recovery (p = 0.06). Pefabloc, and TLM vs. UW preservation, prolonged the tolerable interval between organ recovery and islet isolation. Islet yield, viability, and functionality improved from both marginal and nonmarginal pancreata.
Collapse
|
64
|
Burridge PW, Shapiro AMJ, Ryan EA, Lakey JRT. Future trends in clinical islet transplantation. Transplant Proc 2002; 34:3347-8. [PMID: 12493469 DOI: 10.1016/s0041-1345(02)03613-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- P W Burridge
- Surgical-Medical Research Institute, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | |
Collapse
|
65
|
Bottino R, Balamurugan AN, Bertera S, Pietropaolo M, Trucco M, Piganelli JD. Preservation of human islet cell functional mass by anti-oxidative action of a novel SOD mimic compound. Diabetes 2002; 51:2561-7. [PMID: 12145171 DOI: 10.2337/diabetes.51.8.2561] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The most commonly used technical approach to isolate human pancreatic islets intended for allotransplants generates a product that is hampered by mechanical and chemical insults, which dramatically reduce the mass of viable and functional transplantable cells. We tested a novel class of antioxidant chemical compounds (SOD mimics: AEOL10113 and AEOL10150) to protect human islets from oxidative stress in order to improve the preservation of the isolated tissue. Addition of SOD mimic in culture, after isolation, allowed for the survival of a significantly higher islet cell mass. Functional behavior and phenotypic cell characteristics of the SOD-treated islet preparations were preserved, as was the capacity to normalize diabetic mice, even when a marginal mass of islets was transplanted. The addition of SOD mimic during isolation, before culture, further reduced early cell loss. These results indicate that prompt interventions aimed at blocking oxidative stress can improve human islet survival, preserving a functional islet mass two- to threefold larger than the one usually obtained without adding any antioxidant compound. The ability to preserve functional islets without a dramatic loss represents a major advantage considering the scarce availability of islet tissue for clinical transplantation.
Collapse
Affiliation(s)
- Rita Bottino
- Department of Pediatrics, Division of Immunogenetics, Diabetes Institute, University of Pittsburgh, School of Medicine, Rangos Research Center, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | | | | | | | | | | |
Collapse
|