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The ischaemic preconditioning paradox and its implications for islet isolation from heart-beating and non heart-beating donors. Sci Rep 2022; 12:19321. [PMID: 36369239 PMCID: PMC9652462 DOI: 10.1038/s41598-022-23862-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 11/07/2022] [Indexed: 11/13/2022] Open
Abstract
The impact of ischaemia can severely damage procured donor organs for transplantation. The pancreas, and pancreatic islets in particular, is one of the most sensitive tissues towards hypoxia. The present study was aimed to assess the effect of hypoxic preconditioning (HP) performed ex-vivo in islets isolated from heart-beating donor (HBD) and non heart-beating donor (NHBD) rats. After HP purified islets were cultured for 24 h in hypoxia followed by islet characterisation. Post-culture islet yields were significantly lower in sham-treated NHBD than in HBD. This difference was reduced when NHBD islets were preconditioned. Similar results were observed regarding viability, apoptosis and in vitro function. Reactive oxygen species generation after hypoxic culture was significantly enhanced in sham-treated NHBD than in HBD islets. Again, this difference could be diminished through HP. qRT-PCR revealed that HP decreases pro-apoptotic genes but increases HIF-1 and VEGF. However, the extent of reduction and augmentation was always substantially higher in preconditioned NHBD than in HBD islets. Our findings indicate a lower benefit of HBD islets from HP than NHBD islets. The ischaemic preconditioning paradox suggests that HP should be primarily applied to islets from marginal donors. This observation needs evaluation in human islets.
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Wang Q, Zennadi R. The Role of RBC Oxidative Stress in Sickle Cell Disease: From the Molecular Basis to Pathologic Implications. Antioxidants (Basel) 2021; 10:antiox10101608. [PMID: 34679742 PMCID: PMC8533084 DOI: 10.3390/antiox10101608] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/04/2021] [Accepted: 10/06/2021] [Indexed: 01/14/2023] Open
Abstract
Sickle cell disease (SCD) is an inherited monogenic disorder and the most common severe hemoglobinopathy in the world. SCD is characterized by a point mutation in the β-globin gene, which results in hemoglobin (Hb) S production, leading to a variety of mechanistic and phenotypic changes within the sickle red blood cell (RBC). In SCD, the sickle RBCs are the root cause of the disease and they are a primary source of oxidative stress since sickle RBC redox state is compromised due to an imbalance between prooxidants and antioxidants. This imbalance in redox state is a result of a continuous production of reactive oxygen species (ROS) within the sickle RBC caused by the constant endogenous Hb autoxidation and NADPH oxidase activation, as well as by a deficiency in the antioxidant defense system. Accumulation of non-neutralized ROS within the sickle RBCs affects RBC membrane structure and function, leading to membrane integrity deficiency, low deformability, phosphatidylserine exposure, and release of micro-vesicles. These oxidative stress-associated RBC phenotypic modifications consequently evoke a myriad of physiological changes involved in multi-system manifestations. Thus, RBC oxidative stress in SCD can ultimately instigate major processes involved in organ damage. The critical role of the sickle RBC ROS production and its regulation in SCD pathophysiology are discussed here.
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Mn porphyrins as a novel treatment targeting sickle cell NOXs to reverse and prevent acute vaso-occlusion in vivo. Blood Adv 2021; 4:2372-2386. [PMID: 32479589 DOI: 10.1182/bloodadvances.2020001642] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/28/2020] [Indexed: 12/11/2022] Open
Abstract
In sickle cell disease (SCD), adhesion of sickle red blood cells (SSRBCs) and activated leukocytes in inflamed venules affects blood rheology, causing vaso-occlusive manifestations and vital reduction in microvascular blood flow. Recently, we found that NADPH oxidases (NOXs) create a vicious feedback loop within SSRBCs. This positive feedback loop mediates SSRBC adhesion to the endothelium. We show for the first time the therapeutic effectiveness of the redox-active manganese (Mn) porphyrins MnTnBuOE-2-PyP5+ (MnBuOE; BMX-001) and MnTE-2-PyP5+ (MnE; BMX-010, AEOL10113) to treat established vaso-occlusion in a humanized sickle mouse model of an acute vaso-occlusive crisis using intravital microscopy. These Mn porphyrins can suppress SSRBC NOX activity. Subcutaneous administration of only 1 dose of MnBuOE or MnE at 0.1 to 2 mg/kg after the inflammatory trigger of vaso-occlusion, or simultaneously, reversed and reduced leukocyte and SSRBC adhesion, diminished leukocyte rolling, restored blood flow, and increased survival rate. Furthermore, MnBuOE and MnE administered to sickle mice subcutaneously at 0.1 to 1 mg/kg for 28 days (except on weekends) did not exacerbate anemia, which seemed to be due to downregulation of both SSRBC reactive oxygen species production and exposure of the eryptotic marker phosphatidylserine. In addition, Mn porphyrins ameliorated leukocytosis, venous blood gases, endothelial activation, and organ oxidative damage. Our data suggest that Mn porphyrins, likely by repressing NOX-mediated adhesive function of SSRBCs and activated leukocytes, could represent a novel, safe therapeutic intervention to treat or prevent the establishment of acute pain crises. These NOX-targeted antioxidants merit further assessment in SCD clinical trials.
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Verhoeff K, Henschke SJ, Marfil-Garza BA, Dadheech N, Shapiro AMJ. Inducible Pluripotent Stem Cells as a Potential Cure for Diabetes. Cells 2021; 10:cells10020278. [PMID: 33573247 PMCID: PMC7911560 DOI: 10.3390/cells10020278] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 01/22/2021] [Accepted: 01/24/2021] [Indexed: 02/07/2023] Open
Abstract
Over the last century, diabetes has been treated with subcutaneous insulin, a discovery that enabled patients to forego death from hyperglycemia. Despite novel insulin formulations, patients with diabetes continue to suffer morbidity and mortality with unsustainable costs to the health care system. Continuous glucose monitoring, wearable insulin pumps, and closed-loop artificial pancreas systems represent an advance, but still fail to recreate physiologic euglycemia and are not universally available. Islet cell transplantation has evolved into a successful modality for treating a subset of patients with ‘brittle’ diabetes but is limited by organ donor supply and immunosuppression requirements. A novel approach involves generating autologous or immune-protected islet cells for transplant from inducible pluripotent stem cells to eliminate detrimental immune responses and organ supply limitations. In this review, we briefly discuss novel mechanisms for subcutaneous insulin delivery and define their shortfalls. We describe embryological development and physiology of islets to better understand their role in glycemic control and, finally, discuss cell-based therapies for diabetes and barriers to widespread use. In response to these barriers, we present the promise of stem cell therapy, and review the current gaps requiring solutions to enable widespread use of stem cells as a potential cure for diabetes.
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Affiliation(s)
- Kevin Verhoeff
- Department of Surgery, University of Alberta, Edmonton, AB T6G 2B7, Canada;
- Correspondence: ; Tel.: +1-780-984-1836
| | - Sarah J. Henschke
- Department of Emergency Medicine, University of Saskatchewan, Saskatoon, SK S7N 0W8, Canada;
| | | | - Nidheesh Dadheech
- Alberta Diabetes Institute, University of Alberta, Edmonton, AB T6G 2B7, Canada;
| | - Andrew Mark James Shapiro
- FRCS (Eng) FRCSC MSM FCAHS, Clinical Islet Transplant Program, Alberta Diabetes Institute, Department of Surgery, Canadian National Transplant Research Program, Edmonton, AB T6G 2B7, Canada;
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Batinic-Haberle I, Tome ME. Thiol regulation by Mn porphyrins, commonly known as SOD mimics. Redox Biol 2019; 25:101139. [PMID: 31126869 PMCID: PMC6859569 DOI: 10.1016/j.redox.2019.101139] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 01/18/2019] [Accepted: 02/07/2019] [Indexed: 01/27/2023] Open
Abstract
Superoxide dismutases play an important role in human health and disease. Three decades of effort have gone into synthesizing SOD mimics for clinical use. The result is the Mn porphyrins which have SOD-like activity. Several clinical trials are underway to test the efficacy of these compounds in patients, particularly as radioprotectors of normal tissue during cancer treatment. However, aqueous chemistry data indicate that the Mn porphyrins react equally well with multiple redox active species in cells including H2O2, O2•-, ONOO-, thiols, and ascorbate among others. The redox potential of the Mn porphyrins is midway between the potentials for the oxidation and reduction of O2•-. This positions them to react equally well as oxidants and reductants in cells. The result of this unique chemistry is that: 1) the species the Mn porphyrins react with in vivo will depend on the relative concentrations of the reactive species and Mn porphyrins in the cell of interest, and 2) the Mn porphyrins will act as catalytic (redox cycling) agents in vivo. The ability of the Mn porphyrins to catalyze protein S-glutathionylation means that Mn porphyrins have the potential to globally modulate cellular redox regulatory signaling networks. The purpose of this review is to summarize the data that indicate the Mn porphyrins have diverse reactions in vivo that are the basis of the observed biological effects. The ability to catalyze multiple reactions in vivo expands the potential therapeutic use of the Mn porphyrins to disease models that are not SOD based.
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Affiliation(s)
- Ines Batinic-Haberle
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27710, USA.
| | - Margaret E Tome
- Departments of Pathology and Pharmacology, University of Arizona, Tucson, AZ 85724, USA.
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Abstract
In this Review, we focus on catalytic antioxidant study based on transition metal complexes, organoselenium compounds, supramolecules and protein scaffolds.
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Affiliation(s)
- Riku Kubota
- Department of Applied Chemistry for Environment
- Tokyo Metropolitan University
- Hachioji
- Japan
| | - Shoichiro Asayama
- Department of Applied Chemistry for Environment
- Tokyo Metropolitan University
- Hachioji
- Japan
| | - Hiroyoshi Kawakami
- Department of Applied Chemistry for Environment
- Tokyo Metropolitan University
- Hachioji
- Japan
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Batinic-Haberle I, Tovmasyan A, Spasojevic I. Mn Porphyrin-Based Redox-Active Drugs: Differential Effects as Cancer Therapeutics and Protectors of Normal Tissue Against Oxidative Injury. Antioxid Redox Signal 2018; 29:1691-1724. [PMID: 29926755 PMCID: PMC6207162 DOI: 10.1089/ars.2017.7453] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
SIGNIFICANCE After approximatelty three decades of research, two Mn(III) porphyrins (MnPs), MnTE-2-PyP5+ (BMX-010, AEOL10113) and MnTnBuOE-2-PyP5+ (BMX-001), have progressed to five clinical trials. In parallel, another similarly potent metal-based superoxide dismutase (SOD) mimic-Mn(II)pentaaza macrocycle, GC4419-has been tested in clinical trial on application, identical to that of MnTnBuOE-2-PyP5+-radioprotection of normal tissue in head and neck cancer patients. This clearly indicates that Mn complexes that target cellular redox environment have reached sufficient maturity for clinical applications. Recent Advances: While originally developed as SOD mimics, MnPs undergo intricate interactions with numerous redox-sensitive pathways, such as those involving nuclear factor κB (NF-κB) and nuclear factor E2-related factor 2 (Nrf2), thereby impacting cellular transcriptional activity. An increasing amount of data support the notion that MnP/H2O2/glutathione (GSH)-driven catalysis of S-glutathionylation of protein cysteine, associated with modification of protein function, is a major action of MnPs on molecular level. CRITICAL ISSUES Differential effects of MnPs on normal versus tumor cells/tissues, which support their translation into clinic, arise from differences in their accumulation and redox environment of such tissues. This in turn results in different yields of MnP-driven modifications of proteins. Thus far, direct evidence for such modification of NF-κB, mitogen-activated protein kinases (MAPK), phosphatases, Nrf2, and endogenous antioxidative defenses was provided in tumor, while indirect evidence shows the modification of NF-κB and Nrf2 translational activities by MnPs in normal tissue. FUTURE DIRECTIONS Studies that simultaneously explore differential effects in same animal are lacking, while they are essential for understanding of extremely intricate interactions of metal-based drugs with complex cellular networks of normal and cancer cells/tissues.
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Affiliation(s)
- Ines Batinic-Haberle
- 1 Department of Radiation Oncology, Duke University School of Medicine , Durham, North Carolina
| | - Artak Tovmasyan
- 1 Department of Radiation Oncology, Duke University School of Medicine , Durham, North Carolina
| | - Ivan Spasojevic
- 2 Department of Medicine, Duke University School of Medicine , Durham, North Carolina.,3 PK/PD Core Laboratory, Pharmaceutical Research Shared Resource, Duke Cancer Institute , Durham, North Carolina
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Bruni A, Pepper AR, Pawlick RL, Gala-Lopez B, Gamble A, Kin T, Malcolm AJ, Jones C, Piganelli JD, Crapo JD, Shapiro AMJ. BMX-001, a novel redox-active metalloporphyrin, improves islet function and engraftment in a murine transplant model. Am J Transplant 2018; 18:1879-1889. [PMID: 29464912 DOI: 10.1111/ajt.14705] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 02/09/2018] [Accepted: 02/10/2018] [Indexed: 02/06/2023]
Abstract
Islet transplantation has become a well-established therapy for select patients with type 1 diabetes. Viability and engraftment can be compromised by the generation of oxidative stress encountered during isolation and culture. We evaluated whether the administration of BMX-001 (MnTnBuOE-2-PyP5+ [Mn(III) meso-tetrakis-(N-b-butoxyethylpyridinium-2-yl)porphyrin]) and its earlier derivative, BMX-010 (MnTE-2-PyP [Mn(III) meso-tetrakis-(N-methylpyridinium-2-yl)porphyrin]) could improve islet function and engraftment outcomes. Long-term culture of human islets with BMX-001, but not BMX-010, exhibited preserved in vitro viability. Murine islets isolated and cultured for 24 hours with 34 μmol/L BMX-001 exhibited improved insulin secretion (n = 3 isolations, P < .05) in response to glucose relative to control islets. In addition, 34 μmol/L BMX-001-supplemented murine islets exhibited significantly reduced apoptosis as indicated by terminal deoxynucleotidyl transferase dUTP nick end labeling, compared with nontreated control islets (P < .05). Murine syngeneic islets transplanted under the kidney capsule at a marginal dose of 150 islets revealed 58% of 34 μmol/L BMX-001-treated islet recipients became euglycemic (n = 11 of 19) compared with 19% of nontreated control islet recipients (n = 3 of 19, P < .05). Of murine recipients receiving a marginal dose of human islets cultured with 34 μmol/L BMX-001, 92% (n = 12 of 13) achieved euglycemia compared with 57% of control recipients (n = 8 of 14, P = .11). These results demonstrate that the administration of BMX-001 enhances in vitro viability and augments murine marginal islet mass engraftment.
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Affiliation(s)
- Antonio Bruni
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Department of Surgery, University of Alberta, Edmonton, AB, Canada
- Canadian National Transplant Research Program, Edmonton, AB, Canada
| | - Andrew R Pepper
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Department of Surgery, University of Alberta, Edmonton, AB, Canada
- Canadian National Transplant Research Program, Edmonton, AB, Canada
| | - Rena L Pawlick
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
| | - Boris Gala-Lopez
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Department of Surgery, University of Alberta, Edmonton, AB, Canada
- Canadian National Transplant Research Program, Edmonton, AB, Canada
| | - Anissa Gamble
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Department of Surgery, University of Alberta, Edmonton, AB, Canada
| | - Tatsuya Kin
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
| | - Andrew J Malcolm
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Canadian National Transplant Research Program, Edmonton, AB, Canada
| | | | - Jon D Piganelli
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
- BioMimetix JV, LLC, Englewood, CO, USA
| | - James D Crapo
- Department of Medicine, National Jewish Health, Denver, CO, USA
- BioMimetix JV, LLC, Englewood, CO, USA
| | - A M James Shapiro
- Clinical Islet Transplant Program, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Department of Surgery, University of Alberta, Edmonton, AB, Canada
- Canadian National Transplant Research Program, Edmonton, AB, Canada
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Bral M, Gala-Lopez B, Bigam DL, Freed DH, Shapiro AMJ. Ex situ liver perfusion: Organ preservation into the future. Transplant Rev (Orlando) 2018; 32:132-141. [PMID: 29691119 DOI: 10.1016/j.trre.2018.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 03/27/2018] [Accepted: 03/27/2018] [Indexed: 12/15/2022]
Abstract
In recent years, remarkable progress has occurred in the development of technologies to support ex situ liver perfusion. Building upon extensive preclinical studies in large animal models, pilot and randomized clinical trials have been initiated, and preliminary outcomes suggest more optimal protection of both standard and extended criteria liver grafts. There currently exists an incredible opportunity and need to further refine this technology, determine appropriate viability measures to predict usable liver grafts, and to explore potent protective additive strategies to further optimize the quality of extended criteria organs. These findings will have major bearing in expanding the limited liver donor pool, and may save lives where up to a quarter of listed patients die on wait-lists. Herein we offer a brief overview of the history and current status of ex situ liver perfusion, and discuss future directions that will likely have major impact on the practice of clinical liver transplantation.
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Affiliation(s)
- Mariusz Bral
- Department of Surgery, University of Alberta, 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada; Members of the Canadian National Transplant Research Program (CNTRP), 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada.
| | - Boris Gala-Lopez
- Department of Surgery, University of Alberta, 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada; Members of the Canadian National Transplant Research Program (CNTRP), 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada.
| | - David L Bigam
- Department of Surgery, University of Alberta, 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada; Members of the Canadian National Transplant Research Program (CNTRP), 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada.
| | - Darren H Freed
- Department of Surgery, University of Alberta, 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada; Members of the Canadian National Transplant Research Program (CNTRP), 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada.
| | - A M James Shapiro
- Department of Surgery, University of Alberta, 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada; Members of the Canadian National Transplant Research Program (CNTRP), 2D4.43 Walter D MacKenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta T6G2B7, Canada.
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Gamble A, Pepper AR, Bruni A, Shapiro AMJ. The journey of islet cell transplantation and future development. Islets 2018; 10:80-94. [PMID: 29394145 PMCID: PMC5895174 DOI: 10.1080/19382014.2018.1428511] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 01/12/2018] [Indexed: 02/06/2023] Open
Abstract
Intraportal islet transplantation has proven to be efficacious in preventing severe hypoglycemia and restoring insulin independence in selected patients with type 1 diabetes. Multiple islet infusions are often required to achieve and maintain insulin independence. Many challenges remain in clinical islet transplantation, including substantial islet cell loss early and late after islet infusion. Contributions to graft loss include the instant blood-mediated inflammatory reaction, potent host auto- and alloimmune responses, and beta cell toxicity from immunosuppressive agents. Protective strategies are being tested to circumvent several of these events including exploration of alternative transplantation sites, stem cell-derived insulin producing cell therapies, co-transplantation with mesenchymal stem cells or exploration of novel immune protective agents. Herein, we provide a brief introduction and history of islet cell transplantation, limitations associated with this procedure and methods to alleviate islet cell loss as a means to improve engraftment outcomes.
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Affiliation(s)
- Anissa Gamble
- Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Members of the Canadian National Transplant Research Project (CNTRP), Canada
| | - Andrew R. Pepper
- Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Clinical Islet Transplant Program, University of Alberta, Edmonton, AB, Canada
- Members of the Canadian National Transplant Research Project (CNTRP), Canada
| | - Antonio Bruni
- Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Members of the Canadian National Transplant Research Project (CNTRP), Canada
| | - A. M. James Shapiro
- Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Clinical Islet Transplant Program, University of Alberta, Edmonton, AB, Canada
- Members of the Canadian National Transplant Research Project (CNTRP), Canada
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