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Sample records for clinical islet transplantation

  1. Clinical pancreatic islet transplantation.

    Science.gov (United States)

    Shapiro, A M James; Pokrywczynska, Marta; Ricordi, Camillo

    2017-05-01

    Clinical pancreatic islet transplantation can be considered one of the safest and least invasive transplant procedures. Remarkable progress has occurred in both the technical aspects of islet cell processing and the outcomes of clinical islet transplantation. With >1,500 patients treated since 2000, this therapeutic strategy has moved from a curiosity to a realistic treatment option for selected patients with type 1 diabetes mellitus (that is, those with hypoglycaemia unawareness, severe hypoglycaemic episodes and glycaemic lability). This Review outlines the techniques required for human islet isolation, in vitro culture before the transplant and clinical islet transplantation, and discusses indications, optimization of recipient immunosuppression and management of adjunctive immunomodulatory and anti-inflammatory strategies. The potential risks, long-term outcomes and advances in treatment after the transplant are also discussed to further move this treatment towards becoming a more widely available option for patients with type 1 diabetes mellitus and eventually a potential cure.

  2. Pancreatic islet transplantation. Experimental and clinical aspects

    DEFF Research Database (Denmark)

    Yderstræde, Knud Bonnet

    1987-01-01

    interest has been shown in transplantation of isolated islets either directly, introduced intraportally, intramuscularly, inter alia, or encapsulated in artificial devices providing an immuno-isolation. Clinical application has revealed promising results concerning the immunological aspects. However......, quantitative assessment points to a difficulty in achieving satisfactory amounts of islets to attain normoglycaemia. Work with fetal pancreata has shown these to possess a growth potential in vitro thus, possibly, aiding the quantification of islets in transplantation models. In the field of pancreatic islet...... transplantation, future models include microencapsulation and hybrid artificial devices, both of which provide immuno-isolation - thus the ability of allo- as well as xeno-transplantation. The obvious advantage of immuno-isolated islet transplant, as opposed to segmentally engrafted pancreas, is stressed...

  3. Islet and Stem Cell Encapsulation for Clinical Transplantation

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    Krishnan, Rahul; Alexander, Michael; Robles, Lourdes; Foster 3rd, Clarence E.; Lakey, Jonathan R.T.

    2014-01-01

    Over the last decade, improvements in islet isolation techniques have made islet transplantation an option for a certain subset of patients with long-standing diabetes. Although islet transplants have shown improved graft function, adequate function beyond the second year has not yet been demonstrated, and patients still require immunosuppression to prevent rejection. Since allogeneic islet transplants have experienced some success, the next step is to improve graft function while eliminating the need for systemic immunosuppressive therapy. Biomaterial encapsulation offers a strategy to avoid the need for toxic immunosuppression while increasing the chances of graft function and survival. Encapsulation entails coating cells or tissue in a semipermeable biocompatible material that allows for the passage of nutrients, oxygen, and hormones while blocking immune cells and regulatory substances from recognizing and destroying the cell, thus avoiding the need for systemic immunosuppressive therapy. Despite advances in encapsulation technology, these developments have not yet been meaningfully translated into clinical islet transplantation, for which several factors are to blame, including graft hypoxia, host inflammatory response, fibrosis, improper choice of biomaterial type, lack of standard guidelines, and post-transplantation device failure. Several new approaches, such as the use of porcine islets, stem cells, development of prevascularized implants, islet nanocoating, and multilayer encapsulation, continue to generate intense scientific interest in this rapidly expanding field. This review provides a comprehensive update on islet and stem cell encapsulation as a treatment modality in type 1 diabetes, including a historical outlook as well as current and future research avenues. PMID:25148368

  4. Cellular islet autoimmunity associates with clinical outcome of islet cell transplantation.

    Directory of Open Access Journals (Sweden)

    Volkert A L Huurman

    2008-06-01

    Full Text Available Islet cell transplantation can cure type 1 diabetes (T1D, but only a minority of recipients remains insulin-independent in the following years. We tested the hypothesis that allograft rejection and recurrent autoimmunity contribute to this progressive loss of islet allograft function.Twenty-one T1D patients received cultured islet cell grafts prepared from multiple donors and transplanted under anti-thymocyte globulin (ATG induction and tacrolimus plus mycophenolate mofetil (MMF maintenance immunosuppression. Immunity against auto- and alloantigens was measured before and during one year after transplantation. Cellular auto- and alloreactivity was assessed by lymphocyte stimulation tests against autoantigens and cytotoxic T lymphocyte precursor assays, respectively. Humoral reactivity was measured by auto- and alloantibodies. Clinical outcome parameters--including time until insulin independence, insulin independence at one year, and C-peptide levels over one year--remained blinded until their correlation with immunological parameters. All patients showed significant improvement of metabolic control and 13 out of 21 became insulin-independent. Multivariate analyses showed that presence of cellular autoimmunity before and after transplantation is associated with delayed insulin-independence (p = 0.001 and p = 0.01, respectively and lower circulating C-peptide levels during the first year after transplantation (p = 0.002 and p = 0.02, respectively. Seven out of eight patients without pre-existent T-cell autoreactivity became insulin-independent, versus none of the four patients reactive to both islet autoantigens GAD and IA-2 before transplantation. Autoantibody levels and cellular alloreactivity had no significant association with outcome.In this cohort study, cellular islet-specific autoimmunity associates with clinical outcome of islet cell transplantation under ATG-tacrolimus-MMF immunosuppression. Tailored immunotherapy targeting cellular

  5. Clinical Allogeneic and Autologous Islet Cell Transplantation: Update

    Directory of Open Access Journals (Sweden)

    Shinichi Matsumoto

    2011-06-01

    Full Text Available Islet cell transplantation is categorized as a β-cell replacement therapy for diabetic patients who lack the ability to secrete insulin. Allogeneic islet cell transplantation is for the treatment of type 1 diabetes, and autologous islet cell transplantation is for the prevention of surgical diabetes after a total pancreatectomy. The issues of allogeneic islet cell transplantation include poor efficacy of islet isolation, the need for multiple donor pancreata, difficulty maintaining insulin independence and undesirable side effects of immunosuppressive drugs. Those issues have been solved step by step and allogeneic islet cell transplantation is almost ready to be the standard therapy. The donor shortage will be the next issue and marginal and/or living donor islet cell transplantation might alleviate the issue. Xeno-islet cell transplantation, β-cell regeneration from human stem cells and gene induction of the naïve pancreas represent the next generation of β-cell replacement therapy. Autologous islet cell transplantation after total pancreatectomy for the treatment of chronic pancreatitis with severe abdominal pain is the standard therapy, even though only limited centers are able to perform this treatment. Remote center autologous islet cell transplantation is an attractive option for hospitals performing total pancreatectomies without the proper islet isolation facilities.

  6. Improvement in Outcomes of Clinical Islet Transplantation: 1999–2010

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    Barton, Franca B.; Rickels, Michael R.; Alejandro, Rodolfo; Hering, Bernhard J.; Wease, Stephen; Naziruddin, Bashoo; Oberholzer, Jose; Odorico, Jon S.; Garfinkel, Marc R.; Levy, Marlon; Pattou, Francois; Berney, Thierry; Secchi, Antonio; Messinger, Shari; Senior, Peter A.; Maffi, Paola; Posselt, Andrew; Stock, Peter G.; Kaufman, Dixon B.; Luo, Xunrong; Kandeel, Fouad; Cagliero, Enrico; Turgeon, Nicole A.; Witkowski, Piotr; Naji, Ali; O’Connell, Philip J.; Greenbaum, Carla; Kudva, Yogish C.; Brayman, Kenneth L.; Aull, Meredith J.; Larsen, Christian; Kay, Tom W.H.; Fernandez, Luis A.; Vantyghem, Marie-Christine; Bellin, Melena; Shapiro, A.M. James

    2012-01-01

    OBJECTIVE To describe trends of primary efficacy and safety outcomes of islet transplantation in type 1 diabetes recipients with severe hypoglycemia from the Collaborative Islet Transplant Registry (CITR) from 1999 to 2010. RESEARCH DESIGN AND METHODS A total of 677 islet transplant-alone or islet-after-kidney recipients with type 1 diabetes in the CITR were analyzed for five primary efficacy outcomes and overall safety to identify any differences by early (1999–2002), mid (2003–2006), or recent (2007–2010) transplant era based on annual follow-up to 5 years. RESULTS Insulin independence at 3 years after transplant improved from 27% in the early era (1999–2002, n = 214) to 37% in the mid (2003–2006, n = 255) and to 44% in the most recent era (2007–2010, n = 208; P = 0.006 for years-by-era; P = 0.01 for era alone). C-peptide ≥0.3 ng/mL, indicative of islet graft function, was retained longer in the most recent era (P islet reinfusion rate was lower: 48% by 1 year in 2007–2010 vs. 60–65% in 1999–2006 (P islet graft function (P islet transplantation in recipients who received transplants in 2007–2010 compared with those in 1999–2006, with fewer islet infusions and adverse events per recipient. PMID:22723582

  7. mTOR Inhibition and Clinical Transplantation: Pancreas and Islet.

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    Berney, Thierry; Andres, Axel; Toso, Christian; Majno, Pietro; Squifflet, Jean-Paul

    2018-02-01

    This brief overview discusses the beneficial and deleterious effects of mammalian target of rapamycin (mTOR) inhibitors on β cells, and how sirolimus- and everolimus-based immunosuppression have impacted on practices and outcomes of pancreas and islet transplantation. Sirolimus was the cornerstone of immunosuppressive regimens in islet transplantation at the turn of the millenium, but utilization of mTOR inhibitors has progressively decreased from greater than 80% to less than 50% of islet transplant recipients in more recent years. For whole pancreas transplantation, mTOR inhibitors were used in approximately 20% of patients in the early 2000s, but this dropped over the years to less than 10% currently. This decrease is arguably due to less well-tolerated side effects without the advantage of better outcomes. Nonetheless, mTOR inhibitors remain extremely valuable as second-line immunosuppressants in pancreas and islet transplantation.

  8. Islet Assessment for Transplantation

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    Papas, Klearchos K.; Suszynski, Thomas M.; Colton, Clark. K.

    2010-01-01

    Purpose of review There is a critical need for meaningful viability and potency assays that characterize islet preparations for release prior to clinical islet cell transplantation (ICT). Development, testing, and validation of such assays have been the subject of intense investigation for the past decade. These efforts are reviewed, highlighting the most recent results while focusing on the most promising assays. Recent Findings Assays based on membrane integrity do not reflect true viability when applied to either intact islets or dispersed islet cells. Assays requiring disaggregation of intact islets into individual cells for assessment introduce additional problems of cell damage and loss. Assays evaluating mitochondrial function, specifically mitochondrial membrane potential, bioenergetic status, and cellular oxygen consumption rate (OCR), especially when conducted with intact islets, appear most promising in evaluating their quality prior to ICT. Prospective, quantitative assays based on measurements of OCR with intact islets have been developed, validated and their results correlated with transplant outcomes in the diabetic nude mouse bioassay. Conclusion More sensitive and reliable islet viability and potency tests have been recently developed and tested. Those evaluating mitochondrial function are most promising, correlate with transplant outcomes in mice, and are currently being evaluated in the clinical setting. PMID:19812494

  9. Islet cell transplant: Update on current clinical trials

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    Schuetz, Christian; Markmann, James F.

    2016-01-01

    In the last 15 years clinical islet transplantation has made the leap from experimental procedure to standard of care for a highly selective group of patients. Due to a risk-benefit calculation involving the required systemic immunosuppression the procedure is only considered in patients with type 1 diabetes, complicated by severe hypoglycemia or end stage renal disease. In this review we summarize current outcomes of the procedure and take a look at ongoing and future improvements and refinements of beta cell therapy. PMID:28451515

  10. Application of Digital Image Analysis to Determine Pancreatic Islet Mass and Purity in Clinical Islet Isolation and Transplantation

    Science.gov (United States)

    Wang, Ling-jia; Kissler, Hermann J; Wang, Xiaojun; Cochet, Olivia; Krzystyniak, Adam; Misawa, Ryosuke; Golab, Karolina; Tibudan, Martin; Grzanka, Jakub; Savari, Omid; Grose, Randall; Kaufman, Dixon B; Millis, Michael; Witkowski, Piotr

    2015-01-01

    Pancreatic islet mass, represented by islet equivalent (IEQ), is the most important parameter in decision making for clinical islet transplantation. To obtain IEQ, the sample of islets is routinely counted manually under a microscope and discarded thereafter. Islet purity, another parameter in islet processing, is routinely acquired by estimation only. In this study, we validated our digital image analysis (DIA) system developed using the software of Image Pro Plus for islet mass and purity assessment. Application of the DIA allows to better comply with current good manufacturing practice (cGMP) standards. Human islet samples were captured as calibrated digital images for the permanent record. Five trained technicians participated in determination of IEQ and purity by manual counting method and DIA. IEQ count showed statistically significant correlations between the manual method and DIA in all sample comparisons (r >0.819 and p islet particle number (IPN) and the IEQ/IPN ratio did not differ statistically between manual counting method and DIA. In conclusion, the DIA used in this study is a reliable technique in determination of IEQ and purity. Islet sample preserved as a digital image and results produced by DIA can be permanently stored for verification, technical training and islet information exchange between different islet centers. Therefore, DIA complies better with cGMP requirements than the manual counting method. We propose DIA as a quality control tool to supplement the established standard manual method for islets counting and purity estimation. PMID:24806436

  11. Current Status of Immunomodulatory and Cellular Therapies in Preclinical and Clinical Islet Transplantation

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    Chhabra, Preeti; Brayman, Kenneth L.

    2011-01-01

    Clinical islet transplantation is a β-cell replacement strategy that represents a possible definitive intervention for patients with type 1 diabetes, offering substantial benefits in terms of lowering daily insulin requirements and reducing incidences of debilitating hypoglycemic episodes and unawareness. Despite impressive advances in this field, a limiting supply of islets, inadequate means for preventing islet rejection, and the deleterious diabetogenic and nephrotoxic side effects associated with chronic immunosuppressive therapy preclude its wide-spread applicability. Islet transplantation however allows a window of opportunity for attempting various therapeutic manipulations of islets prior to transplantation aimed at achieving superior transplant outcomes. In this paper, we will focus on the current status of various immunosuppressive and cellular therapies that promote graft function and survival in preclinical and clinical islet transplantation with special emphasis on the tolerance-inducing capacity of regulatory T cells as well as the β-cells regenerative capacity of stem cells. PMID:22046502

  12. Current Status of Immunomodulatory and Cellular Therapies in Preclinical and Clinical Islet Transplantation

    Directory of Open Access Journals (Sweden)

    Preeti Chhabra

    2011-01-01

    Full Text Available Clinical islet transplantation is a -cell replacement strategy that represents a possible definitive intervention for patients with type 1 diabetes, offering substantial benefits in terms of lowering daily insulin requirements and reducing incidences of debilitating hypoglycemic episodes and unawareness. Despite impressive advances in this field, a limiting supply of islets, inadequate means for preventing islet rejection, and the deleterious diabetogenic and nephrotoxic side effects associated with chronic immunosuppressive therapy preclude its wide-spread applicability. Islet transplantation however allows a window of opportunity for attempting various therapeutic manipulations of islets prior to transplantation aimed at achieving superior transplant outcomes. In this paper, we will focus on the current status of various immunosuppressive and cellular therapies that promote graft function and survival in preclinical and clinical islet transplantation with special emphasis on the tolerance-inducing capacity of regulatory T cells as well as the -cells regenerative capacity of stem cells.

  13. Cost and clinical outcome of islet transplantation in Norway 2010-2015.

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    Schive, Simen W; Foss, Aksel; Sahraoui, Afaf; Kloster-Jensen, Kristine; Hafsahl, Geir; Kvalheim, Gunnar; Lundgren, Torbjørn; von Zur-Mühlen, Bengt; Felldin, Marie; Rafael, Ehab; Lempinen, Marko; Korsgren, Olle; Jenssen, Trond G; Mishra, Vinod; Scholz, Hanne

    2017-01-01

    Islet transplantation is a minimally invasive β-cell replacement strategy. Islet transplantation is a reimbursed treatment in Norway. Here, we summarize the cost and clinical outcome of 31 islet transplantations performed at Oslo University Hospital (OUS) from January 2010 to June 2015. Patients were retrospectively divided into three groups. Thirteen patients received either one or two islet transplantation alone (ITA), while five patients received islet transplantation after previous solid organ transplantation. For the group receiving 2 ITA, Kaplan-Meier estimates show an insulin independence of 20% more than 4 years after their last transplantation. An estimated 70% maintain at least partial graft function, defined as fasting C-peptide >0.1 nmol L -1 , and 47% maintain a HbA1c below 6.5% or 2 percent points lower than before ITA. For all groups combined, we estimate that 44% of the patients have a 50% reduction in insulin requirement 4 years after the initial islet transplantation. The average cost for an islet transplantation procedure was 347 297±60 588 NOK, or 35 424±6182 EUR, of which isolation expenses represent 34%. We hereby add to the common pool of growing experience with islet transplantation and also describe the cost of the treatment at our center. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Pancreatic Islet Cell Transplantation

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    Warnock, Garth L.; Rajotte, Ray V.

    1992-01-01

    Transplantation of insulin-producing tissue offers a physiologic approach to restoration of glycemic control. Whereas transplantation of vascularized pancreatic grafts has recently achieved encouraging results, pancreatic islet cell transplantation holds the promise of low morbidity and reduced requirements for agressive immunosuppression for recipients. Islet cell transplantation was recently demonstrated to induce euglycemia with insulin independence. Imagesp1656-a PMID:21221366

  15. Posttransplant Lymphoproliferative Disorder After Clinical Islet Transplantation: Report of the First Two Cases.

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    Peters, A; Olateju, T; Deschenes, J; Shankarnarayan, S H; Chua, N; Shapiro, A M J; Senior, P

    2017-09-01

    We report the first two cases of posttransplant lymphoproliferative disorder (PTLD) in recipients of islet transplants worldwide. First, a 44-year-old recipient of three islet infusions developed PTLD 80 months after his initial transplantation, presenting with abdominal pain and diffuse terminal ileum thickening on imaging. He was treated with surgical excision, reduction of immunosuppression, and rituximab. Seven months later, he developed central nervous system PTLD, presenting with vertigo and diplopia; immunosuppression was discontinued, resulting in graft loss, and he was given high-dose methotrexate and underwent consolidative autologous stem cell transplantation. He remains in remission 37 months after the initial diagnosis. Second, a 58-year-old female recipient of two islet infusions developed PTLD 24 months after initial islet infusion, presenting with pancytopenia secondary to extensive bone marrow involvement. Immunosuppression was discontinued, resulting in graft loss, and she received rituximab and chemotherapy, achieving complete remission. Both patients were monomorphic B cell PTLD subtype by histology and negative for Epstein-Barr virus in tissue or blood. These cases document the first occurrences of this rare complication in islet transplantation, likely secondary to prolonged, intensive immunosuppression, and highlight the varying clinical manifestations of PTLD. Further studies are needed to determine incidence rate and risk factors in islet transplantation. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  16. Update on Islet Transplantation

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    McCall, Michael; James Shapiro, A.M.

    2012-01-01

    Clinical islet transplantation has progressed considerably over the past 12 years, and >750 patients with type 1 diabetes have received islet transplants internationally over this time. Many countries are beginning to accept the transition from research to accepted and funded clinical care, especially for patients with brittle control that cannot be stabilized by more conventional means. Major challenges remain, including the need for more than one donor, and the requirement for potent, chronic immunosuppression. Combining immunological tolerance both to allo- and autoantigens, and a limitless expandable source of stem cell- or xenograft-derived insulin-secreting cells represent remaining hurdles in moving this effective treatment to a potential cure for all those with type 1 or 2 diabetes. PMID:22762022

  17. Pancreas Islet Transplantation for Patients With Type 1 Diabetes Mellitus: A Clinical Evidence Review.

    Science.gov (United States)

    2015-01-01

    Type 1 diabetes mellitus is caused by the autoimmune destruction of pancreatic beta (β) cells, resulting in severe insulin deficiency. Islet transplantation is a β-cell replacement therapeutic option that aims to restore glycemic control in patients with type 1 diabetes. The objective of this study was to determine the clinical effectiveness of islet transplantation in patients with type 1 diabetes, with or without kidney disease. We conducted a systematic review of the literature on islet transplantation for type 1 diabetes, including relevant health technology assessments, systematic reviews, meta-analyses, and observational studies. We used a two-step process: first, we searched for systematic reviews and health technology assessments; second, we searched primary studies to update the chosen health technology assessment. The Assessment of Multiple Systematic Reviews measurement tool was used to examine the methodological quality of the systematic reviews and health technology assessments. We assessed the quality of the body of evidence and the risk of bias according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. Our searched yielded 1,354 citations. One health technology assessment, 11 additional observational studies to update the health technology assessment, one registry report, and four guidelines were included; the observational studies examined islet transplantation alone, islet-after-kidney transplantation, and simultaneous islet-kidney transplantation. In general, low to very low quality of evidence exists for islet transplantation in patients with type 1 diabetes with difficult-to-control blood glucose levels, with or without kidney disease, for these outcomes: health-related quality of life, secondary complications of diabetes, glycemic control, and adverse events. However, high quality of evidence exists for the specific glycemic control outcome of insulin independence compared with

  18. Pancreatic islet transplantation

    Directory of Open Access Journals (Sweden)

    Corrêa-Giannella Maria

    2009-09-01

    Full Text Available Abstract Background No formulation of exogenous insulin available to date has yet been able to mimic the physiological nictemeral rhythms of this hormone, and despite all engineering advancements, the theoretical proposal of developing a mechanical replacement for pancreatic β cell still has not been reached. Thus, the replacement of β cells through pancreas and pancreatic islet transplantation are the only concrete alternatives for re-establishing the endogenous insulin secretion in type 1 diabetic patients. Since only 1 to 1.5% of the pancreatic mass corresponds to endocrine tissue, pancreatic islets transplantation arises as a natural alternative. Data from the International Islet Transplant Registry (ITR from 1983 to December 2000 document a total of 493 transplants performed around the world, with progressively worse rates of post-transplant insulin independence. In 2000, the "Edmonton Protocol" introduced several modifications to the transplantation procedure, such as the use of a steroid-free immunosuppression regimen and transplantation of a mean islet mass of 11,000 islet equivalents per kilogram, which significantly improved 1-year outcomes. Although the results of a 5-year follow-up in 65 patients demonstrated improvement in glycemic instability in a significant portion of them, only 7.5% of the patients have reached insulin independence, indicating the need of further advances in the preservation of the function of transplanted islet. In addition to the scarcity of organs available for transplantation, islets transplantation still faces major challenges, specially those related to cell loss during the process of islet isolation and the losses related to the graft site, apoptosis, allorejection, autoimmunity, and immunosuppression. The main strategies to optimize islet transplantation aim at improving all these aspects. Conclusion Human islet transplantation should be regarded as an intervention that can decrease the frequency of

  19. Current issues in allogeneic islet transplantation.

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    Chang, Charles A; Lawrence, Michael C; Naziruddin, Bashoo

    2017-10-01

    Transplantation of allogenic pancreatic islets is a minimally invasive treatment option to control severe hypoglycemia and dependence on exogenous insulin among type 1 diabetes (T1D) patients. This overview summarizes the current issues and progress in islet transplantation outcomes and research. Several clinical trials from North America and other countries have documented the safety and efficacy of clinical islet transplantation for T1D patients with impaired hypoglycemia awareness. A recently completed phase 3 clinical trial allows centres in the United States to apply for a Food and Drug Administration Biologics License for the procedure. Introduction of anti-inflammatory drugs along with T-cell depleting induction therapy has significantly improved long-term function of transplanted islets. Research into islet biomarkers, immunosuppression, extrahepatic transplant sites and potential alternative beta cell sources is driving further progress. Allogeneic islet transplantation has vastly improved over the past two decades. Success in restoration of glycemic control and hypoglycemic awareness after islet transplantation has been further highlighted by clinical trials. However, lack of effective strategies to maintain long-term islet function and insufficient sources of donor tissue still impose limitations to the widespread use of islet transplantation. In the United States, wide adoption of this technology still awaits regulatory approval and, importantly, a financial mechanism to support the use of this technology.

  20. Evaluation of MicroRNA375 as a Novel Biomarker for Graft Damage in Clinical Islet Transplantation.

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    Kanak, Mazhar A; Takita, Morihito; Shahbazov, Rauf; Lawrence, Michael C; Chung, Wen Yuan; Dennison, Ashley R; Levy, Marlon F; Naziruddin, Bashoo

    2015-08-01

    Early and sensitive detection of islet graft damage is essential for improving posttransplant outcomes. MicroRNA 375 (miR375) has been reported as a biomarker of pancreatic β-cell death in small animal models. The miR375 levels were measured in purified human islets, sera from patients with autologous and allogeneic islet transplantation as well as total pancreatectomy alone (nontransplanted group). The miR375 levels were also determined in a miniaturized in vitro tube model comprising human islets and autologous blood. The miR375 expression level in islets was dose-dependent (P islet damage in plasma in the in vitro model (P = 0.003). Clinical analysis revealed that circulating miR375 levels in both autologous and allogeneic islet recipients were significantly elevated for 7 days after islet infusion, compared with the nontransplanted group (P = 0.005 and islet graft damage among 3 different anti-inflammatory protocols for clinical autologous transplantation (P islet transplantation because serum C-peptide and proinsulin levels are difficult to interpret due to the influence of multiple factors, such as β-cell stress and physiological response.

  1. Inflammatory Response in Islet Transplantation

    Directory of Open Access Journals (Sweden)

    Mazhar A. Kanak

    2014-01-01

    Full Text Available Islet cell transplantation is a promising beta cell replacement therapy for patients with brittle type 1 diabetes as well as refractory chronic pancreatitis. Despite the vast advancements made in this field, challenges still remain in achieving high frequency and long-term successful transplant outcomes. Here we review recent advances in understanding the role of inflammation in islet transplantation and development of strategies to prevent damage to islets from inflammation. The inflammatory response associated with islets has been recognized as the primary cause of early damage to islets and graft loss after transplantation. Details on cell signaling pathways in islets triggered by cytokines and harmful inflammatory events during pancreas procurement, pancreas preservation, islet isolation, and islet infusion are presented. Robust control of pre- and peritransplant islet inflammation could improve posttransplant islet survival and in turn enhance the benefits of islet cell transplantation for patients who are insulin dependent. We discuss several potent anti-inflammatory strategies that show promise for improving islet engraftment. Further understanding of molecular mechanisms involved in the inflammatory response will provide the basis for developing potent therapeutic strategies for enhancing the quality and success of islet transplantation.

  2. Inflammatory Response in Islet Transplantation

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    Kanak, Mazhar A.; Kunnathodi, Faisal; Lawrence, Michael C.; Levy, Marlon F.

    2014-01-01

    Islet cell transplantation is a promising beta cell replacement therapy for patients with brittle type 1 diabetes as well as refractory chronic pancreatitis. Despite the vast advancements made in this field, challenges still remain in achieving high frequency and long-term successful transplant outcomes. Here we review recent advances in understanding the role of inflammation in islet transplantation and development of strategies to prevent damage to islets from inflammation. The inflammatory response associated with islets has been recognized as the primary cause of early damage to islets and graft loss after transplantation. Details on cell signaling pathways in islets triggered by cytokines and harmful inflammatory events during pancreas procurement, pancreas preservation, islet isolation, and islet infusion are presented. Robust control of pre- and peritransplant islet inflammation could improve posttransplant islet survival and in turn enhance the benefits of islet cell transplantation for patients who are insulin dependent. We discuss several potent anti-inflammatory strategies that show promise for improving islet engraftment. Further understanding of molecular mechanisms involved in the inflammatory response will provide the basis for developing potent therapeutic strategies for enhancing the quality and success of islet transplantation. PMID:24883060

  3. Pancreas preservation for pancreas and islet transplantation

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    Iwanaga, Yasuhiro; Sutherland, David E.R.; Harmon, James V.; Papas, Klearchos K.

    2010-01-01

    Purpose of review To summarize advances and limitations in pancreas procurement and preservation for pancreas and islet transplantation, and review advances in islet protection and preservation. Recent findings Pancreases procured after cardiac death, with in-situ regional organ cooling, have been successfully used for islet transplantation. Colloid-free Celsior and histidine-tryptophan-ketoglutarate preservation solutions are comparable to University of Wisconsin solution when used for cold storage before pancreas transplantation. Colloid-free preservation solutions are inferior to University of Wisconsin solution for pancreas preservation prior to islet isolation and transplantation. Clinical reports on pancreas and islet transplants suggest that the two-layer method may not offer significant benefits over cold storage with the University of Wisconsin solution: improved oxygenation may depend on the graft size; benefits in experimental models may not translate to human organs. Improvements in islet yield and quality occurred from pancreases treated with inhibitors of stress-induced apoptosis during procurement, storage, isolation or culture. Pancreas perfusion may be desirable before islet isolation and transplantation and may improve islet yields and quality. Methods for real-time, noninvasive assessment of pancreas quality during preservation have been implemented and objective islet potency assays have been developed and validated. These innovations should contribute to objective evaluation and establishment of improved pancreas preservation and islet isolation strategies. Summary Cold storage may be adequate for preservation before pancreas transplants, but insufficient when pancreases are processed for islets or when expanded donors are used. Supplementation of cold storage solutions with cytoprotective agents and perfusion may improve pancreas and islet transplant outcomes. PMID:18685343

  4. Advances and Challenges in Islet Transplantation: Islet Procurement Rates and Lessons Learned from Suboptimal Islet Transplantation

    OpenAIRE

    Annette Plesner; C. Bruce Verchere

    2011-01-01

    The initial step in successful islet transplantation is procurement of healthy donor islets. Given the limited number of donor pancreata selected for islet isolation and that islets from multiple donors are typically required to obtain insulin independence, it is critical to improve pancreas procurement rates and yield of islets for transplantation. Islets are delicate microorgans that are susceptible to apoptosis, hypoxia, and ischemia during isolation, culture, and the peritransplant period...

  5. Hepatic steatosis after islet transplantation: Can ultrasound predict the clinical outcome? A longitudinal study in 108 patients.

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    Venturini, Massimo; Maffi, Paola; Querques, Giulia; Agostini, Giulia; Piemonti, Lorenzo; Sironi, Sandro; De Cobelli, Francesco; Fiorina, Paolo; Secchi, Antonio; Del Maschio, Alessandro

    2015-08-01

    Percutaneous intra-portal islet transplantation (PIPIT) is a less invasive, safer, and repeatable therapeutic option for brittle type 1 diabetes, compared to surgical pancreas transplantation. Hepatic steatosis is a consequence of the islet engraftment but it is curiously present in a limited number of patients and its meaning is controversial. The aims of this study were to assess hepatic steatosis at ultrasound (US) after PIPIT investigating its relationship with graft function and its role in predicting the clinical outcome. From 1996 to 2012, 108 patients underwent PIPIT: 83 type-1 diabetic patients underwent allo-transplantation, 25 auto-transplantation. US was performed at baseline, 6, 12, and 24 months, recording steatosis prevalence, first detection, duration, and distribution. Contemporaneously, steatotic and non-steatotic patients were compared for the following parameters: infused islet mass, insulin independence rate, β-score, C-peptide, glycated hemoglobin, exogenous insulin requirement, and fasting plasma glucose. Steatosis at US was detected in 21/108 patients, 20/83 allo-transplanted and 1/25 auto-transplanted, mostly at 6 and 12 months. Infused islet mass was significantly higher in steatotic than non-steatotic patients (IE/kg: S=10.822; NS=6138; p=0.001). Metabolically, steatotic patients had worse basal conditions, but better islet function when steatosis was first detected, after which progressive islet exhaustion, along with steatosis disappearance, was observed. Conversely, in non-steatotic patients these parameters remained stable in time. Number of re-transplantations was significantly higher in steatotic than in non-steatotic patients (1.8 vs 1.1; p=0.001). Steatosis at US seems to be related to the islet mass and local overworking activity. It precedes metabolic alterations and can predict graft dysfunction addressing to therapeutic decisions before islet exhaustion. If steatosis does not appear, no conclusion can be drawn. Copyright

  6. Islet Transplantation without Borders Enabling islet transplantation in Greece with international collaboration and innovative technology

    Science.gov (United States)

    Papas, Klearchos K; Karatzas, Theodore; Berney, Thierry; Minor, Thomas; Pappas, Paris; Pattou, François; Shaw, James; Toso, Christian; Schuurman, Henk-Jan

    2012-01-01

    Recently, initiatives have been undertaken to establish an islet transplantation program in Athens, Greece. A major hurtle is the high cost associated with the establishment and maintenance of a clinical-grade islet manufacturing center. A collaboration was established with the University Hospitals of Geneva, Switzerland, to enable remote islet cell manufacturing with an established and validated fully operational team. However, remote islet manufacturing requires shipment of the pancreas from the procurement to the islet manufacturing site (in this case from anywhere in Greece to Geneva) and then shipment of the islets from the manufacturing site to the transplant site (from Geneva to Athens). To address challenges related to cold ischemia time of the pancreas and shipment time of islets, a collaboration was initiated with the University of Arizona, Tucson, USA. An international workshop was held in Athens, December 2011, to mark the start of this collaborative project. Experts in the field presented in three main sessions: [1] Islet transplantation: state-of-the-art, and the “network approach”; [2] Technical aspects of clinical islet transplantation and outcomes; and [3] Islet manufacturing – from the donated pancreas to the islet product. This manuscript presents a summary of the workshop. PMID:23330863

  7. Impact of islet size on pancreatic islet transplantation and potential interventions to improve outcome.

    Science.gov (United States)

    Zorzi, Daria; Phan, Tammy; Sequi, Marco; Lin, Yong; Freeman, Daniel H; Cicalese, Luca; Rastellini, Cristiana

    2015-01-01

    Better results have been recently reported in clinical pancreatic islet transplantation (ITX) due mostly to improved isolation techniques and immunosuppression; however, some limitations still exist. It is known that following transplantation, 30% to 60% of the islets are lost. In our study, we have investigated 1) the role of size as a factor affecting islet engraftment and 2) potential procedural manipulations to increase the number of smaller functional islets that can be transplanted. C57/BL10 mice were used as donors and recipients in a syngeneic islet transplant model. Isolated islets were divided by size (large, >300 μm; medium 150-300 μm; small, <150 μm). Each size was transplanted in chemically induced diabetic mice as full (600 IEQ), suboptimal (400 IEQ), and marginal mass (200 IEQ). Control animals received all size islets. Engraftment was defined as reversal of diabetes by day 7 posttransplantation. When the superiority of smaller islets was observed, strategies of overdigestion and fragmentation were adopted during islet isolation in the attempt to reduce islet size and improve engraftment. Smaller islets were significantly superior in engraftment compared to medium, large, and control (all sizes) groups. This was more evident when marginal mass data were compared. In all masses, success decreased as islet size increased. Once islets were engrafted, functionality was not affected by size. When larger islets were fragmented, a significant decrease in islet functionality was observed. On the contrary, if pancreata were slightly overdigested, although not as successful as small naive islets, an increase in engraftment was observed when compared to the control group. In conclusion, smaller islets are superior in engraftment following islet transplantation. Fragmentation has a deleterious effect on islet engraftment. Islet isolations can be performed by reducing islet size with slight overdigestion, and it can be safely adopted to improve clinical

  8. Current status and outlook of pancreatic islets transplantation research

    International Nuclear Information System (INIS)

    Wang Wei; Ye Bin

    2006-01-01

    Diabetes is a common disease, severely harmful to the human's health and life quality. The pancreatic islets transplantation can correct the patient's hyperglycemia, stop or even reverse the progress of the complication and thus decrease the mortality of diabetic patients. It is the most safe and efficient therapy for diabetes. Since the Edmonton Protocol got success in pancreatic islet transplantation in 2000, it has been more and more interested because of its great clinical curative effect. Research strategy of islet transplantation is now focussed on increasing the acquired islets with normal viability, selecting the best transplantation pathway, and improving the immunosuppression protocol. The shortage of human pancreatic donor is an ever unsolved problem in clinical application. The potential resolutions may include acquisition from xenogenic-islets; islets originated from stem cells, and islets from the living-donor human pancreas. The islets transplantation will open a new application field for interventional radiology. (authors)

  9. Portal vein thrombosis is a potentially preventable complication in clinical islet transplantation

    Science.gov (United States)

    Kawahara, Toshiyasu; Kin, Tatsuya; Kashkoush, Samy; Gala-Lopez, Boris; Bigam, David L.; Kneteman, Norman M.; Koh, Angela; Senior, Peter A.; Shapiro, A.M. James

    2011-01-01

    Percutaneous transhepatic portal access avoids surgery, but is rarely associated with bleeding or portal venous thrombosis. We herein report our large, single-center experience of percutaneous islet implantation, and evaluate risk factors of portal vein thrombosis and graft function. Prospective data was collected on 268 intraportal islet transplants (122 subjects). A portal venous Doppler ultrasound was obtained on Days 1 and 7 days posttransplant. Therapeutic heparinization, complete ablation of the portal catheter tract with Avitene paste, and limiting packed cell volume to islet transplant procedures over the past 5 years. In the previous cumulative experience, partial thrombosis did not affect islet function. Standard liver volume correlated negatively (r=−0.257, Pislet transplantation, provided therapeutic anticoagulation is maintained, and packed cell volume is limited to <5 ml. PMID:21883914

  10. Risk factors for islet loss during culture prior to transplantation.

    Science.gov (United States)

    Kin, Tatsuya; Senior, Peter; O'Gorman, Doug; Richer, Brad; Salam, Abdul; Shapiro, Andrew Mark James

    2008-11-01

    Culturing islets can add great flexibility to a clinical islet transplant program. However, a reduction in the islet mass has been frequently observed during culture and its degree varies. The aim of this study was to identify the risk factors associated with a significant islet loss during culture. One-hundred and four islet preparations cultured in an attempt to use for transplantation constituted this study. After culture for 20 h (median), islet yield significantly decreased from 363 309 +/- 12 647 to 313 035 +/- 10 862 islet equivalent yield (IE) (mean +/- SE), accompanied by a reduction in packed tissue volume from 3.9 +/- 0.1 to 3.0 +/- 0.1 ml and islet index (IE/islet particle count) from 1.20 +/- 0.04 to 1.05 +/- 0.04. Culture did not markedly alter islet purity or percent of trapped islet. Morphology score and viability were significantly improved after culture. Of 104 islet preparations, 37 suffered a substantial islet loss (> 20%) over culture. Factors significantly associated with risk of islet loss identified by univariate analysis were longer cold ischemia time, two-layer method (TLM) preservation, lower islet purity, and higher islet index. Multivariate analysis revealed that independent predictors of islet loss were higher islet index and the use of TLM. This study provides novel information on the link between donor- isolation factors and islet loss during culture.

  11. Benefits of PEGylation in the early post-transplant period of intraportal islet transplantation as assessed by magnetic resonance imaging of labeled islets.

    Science.gov (United States)

    Jin, Sang-Man; Oh, Seung-Hoon; Oh, Bae Jun; Suh, Sunghwan; Bae, Ji Cheol; Lee, Jung Hee; Lee, Myung-Shik; Lee, Moon-Kyu; Kim, Kwang-Won; Kim, Jae Hyeon

    2014-01-01

    While a few studies have demonstrated the benefit of PEGylation in islet transplantation, most have employed renal subcapsular models and none have performed direct comparisons of islet mass in intraportal islet transplantation using islet magnetic resonance imaging (MRI). In this study, our aim was to demonstrate the benefit of PEGylation in the early post-transplant period of intraportal islet transplantation with a novel algorithm for islet MRI. Islets were PEGylated after ferucarbotran labeling in a rat syngeneic intraportal islet transplantation model followed by comparisons of post-transplant glycemic levels in recipient rats infused with PEGylated (n = 12) and non-PEGylated (n = 13) islets. The total area of hypointense spots and the number of hypointense spots larger than 1.758 mm(2) of PEGylated and non-PEGylated islets were quantitatively compared. The total area of hypointense spots (P islet group 7 and 14 days post translation (DPT). These results translated into better post-transplant outcomes in the PEGylated islet group 28 DPT. In validation experiments, MRI parameters obtained 1, 7, and 14 DPT predicted normoglycemia 4 wk post-transplantation. We directly demonstrated the benefit of islet PEGylation in protection against nonspecific islet destruction in the early post-transplant period of intraportal islet transplantation using a novel algorithm for islet MRI. This novel algorithm could serve as a useful tool to demonstrate such benefit in future clinical trials of islet transplantation using PEGylated islets.

  12. Islet transplantation in type 1 diabetes

    NARCIS (Netherlands)

    de Kort, H.; de Koning, E.; Rabelink, T.; Bruijn, J.A.; Bajema, I.

    2011-01-01

    Hanneke de Kort, research fellow1, Eelco J de Koning, associate professor, head of clinical islet transplantation programme234, Ton J Rabelink, professor of medicine, chair of department of nephrology2, Jan A Bruijn, professor immunopathology1, Ingeborg M Bajema, renal and transplantation

  13. Evolution of Islet Transplantation for the Last 30 Years.

    Science.gov (United States)

    Farney, Alan C; Sutherland, David E R; Opara, Emmanuel C

    2016-01-01

    In this article, we will review the changes that have occurred in islet transplantation at the birth of Pancreas 30 years ago. The first attempts at β-cell replacement in humans, pancreas and islet transplantation, were performed in the 1960s and 1970s. Although pancreas transplantation has been an accepted treatment for severe labile diabetes predating the emergence of the journal, allogeneic islet transplantation remains experimental. Current investigations within islet transplantation focus to improve islet function after transplantation. Improving islet viability during isolation, exploring ways to increase engraftment, and protection from the host immune system are some of the goals of these investigative efforts. The major barriers to clinical islet transplantation are shortage of human pancreas, the need for immunosuppression, and the inadequacy of the islet isolation process. It is generally accepted that islet encapsulation is an immunoisolation tool with good potential to address the first 2 of those barriers. We have therefore devoted a major part of this review to the critical factors needed to make it a clinical reality. With improved islet isolation techniques and determination of the best site of engraftment as well as improved encapsulation techniques, we hope that islet transplantation could someday achieve routine clinical use.

  14. Islet product characteristics and factors related to successful human islet transplantation from the Collaborative Islet Transplant Registry (CITR) 1999-2010.

    Science.gov (United States)

    Balamurugan, A N; Naziruddin, B; Lockridge, A; Tiwari, M; Loganathan, G; Takita, M; Matsumoto, S; Papas, K; Trieger, M; Rainis, H; Kin, T; Kay, T W; Wease, S; Messinger, S; Ricordi, C; Alejandro, R; Markmann, J; Kerr-Conti, J; Rickels, M R; Liu, C; Zhang, X; Witkowski, P; Posselt, A; Maffi, P; Secchi, A; Berney, T; O'Connell, P J; Hering, B J; Barton, F B

    2014-11-01

    The Collaborative Islet Transplant Registry (CITR) collects data on clinical islet isolations and transplants. This retrospective report analyzed 1017 islet isolation procedures performed for 537 recipients of allogeneic clinical islet transplantation in 1999-2010. This study describes changes in donor and islet isolation variables by era and factors associated with quantity and quality of final islet products. Donor body weight and BMI increased significantly over the period (pIslet yield measures have improved with time including islet equivalent (IEQ)/particle ratio and IEQs infused. The average dose of islets infused significantly increased in the era of 2007-2010 when compared to 1999-2002 (445.4±156.8 vs. 421.3±155.4×0(3) IEQ; pIslet purity and total number of β cells significantly improved over the study period (pislets has remained consistently very high through this period, and differs substantially from nonclinical islets. In multivariate analysis of all recipient, donor and islet factors, and medical management factors, the only islet product characteristic that correlated with clinical outcomes was total IEQs infused. This analysis shows improvements in both quantity and some quality criteria of clinical islets produced over 1999-2010, and these parallel improvements in clinical outcomes over the same period. © 2014 The Authors. American Journal of Transplantation Published by Wiley Periodicals, Inc. on behalf of American Society of Transplant Surgeons.

  15. Novel immunological strategies for islet transplantation.

    Science.gov (United States)

    Tezza, Sara; Ben Nasr, Moufida; Vergani, Andrea; Valderrama Vasquez, Alessandro; Maestroni, Anna; Abdi, Reza; Secchi, Antonio; Fiorina, Paolo

    2015-08-01

    Islet transplantation has been demonstrated to improve glycometabolic control, to reduce hypoglycemic episodes and to halt the progression of diabetic complications. However, the exhaustion of islet function and the side effects related to chronic immunosuppression limit the spread of this technique. Consequently, new immunoregulatory protocols have been developed, with the aim to avoid the use of a life-time immunosuppression. Several approaches have been tested in preclinical models, and some are now under clinical evaluation. The development of new small molecules and new monoclonal or polyclonal antibodies is continuous and raises the possibility of targeting new costimulatory pathways or depleting particular cell types. The use of stem cells and regulatory T cells is underway to take advantage of their immunological properties and to induce tolerance. Xenograft islet transplantation, although having severe problems in terms of immunological compatibility, could theoretically provide an unlimited source of donors; using pigs carrying human immune antigens has showed indeed promising results. A completely different approach, the use of encapsulated islets, has been developed; synthetic structures are used to hide islet alloantigen from the immune system, thus preserving islet endocrine function. Once one of these strategies is demonstrated safe and effective, it will be possible to establish clinical islet transplantation as a treatment for patients with type 1 diabetes long before the onset of diabetic-related complications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. The journey of islet cell transplantation and future development.

    Science.gov (United States)

    Gamble, Anissa; Pepper, Andrew R; Bruni, Antonio; Shapiro, A M James

    2018-03-04

    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.

  17. Islet Product Characteristics and Factors Related to Successful Human Islet Transplantation From the Collaborative Islet Transplant Registry (CITR) 1999–2010

    Science.gov (United States)

    Balamurugan, A N; Naziruddin, B; Lockridge, A; Tiwari, M; Loganathan, G; Takita, M; Matsumoto, S; Papas, K; Trieger, M; Rainis, H; Kin, T; Kay, T W; Wease, S; Messinger, S; Ricordi, C; Alejandro, R; Markmann, J; Kerr-Conti, J; Rickels, M R; Liu, C; Zhang, X; Witkowski, P; Posselt, A; Maffi, P; Secchi, A; Berney, T; O’Connell, P J; Hering, B J; Barton, F B

    2014-01-01

    The Collaborative Islet Transplant Registry (CITR) collects data on clinical islet isolations and transplants. This retrospective report analyzed 1017 islet isolation procedures performed for 537 recipients of allogeneic clinical islet transplantation in 1999–2010. This study describes changes in donor and islet isolation variables by era and factors associated with quantity and quality of final islet products. Donor body weight and BMI increased significantly over the period (p Islet yield measures have improved with time including islet equivalent (IEQ)/particle ratio and IEQs infused. The average dose of islets infused significantly increased in the era of 2007–2010 when compared to 1999–2002 (445.4 ± 156.8 vs. 421.3 ± 155.4 ×103 IEQ; p Islet purity and total number of β cells significantly improved over the study period (p islets has remained consistently very high through this period, and differs substantially from nonclinical islets. In multivariate analysis of all recipient, donor and islet factors, and medical management factors, the only islet product characteristic that correlated with clinical outcomes was total IEQs infused. This analysis shows improvements in both quantity and some quality criteria of clinical islets produced over 1999–2010, and these parallel improvements in clinical outcomes over the same period. PMID:25278159

  18. Feasibility of islet magnetic resonance imaging using ferumoxytol in intraportal islet transplantation.

    Science.gov (United States)

    Jin, Sang-Man; Oh, Seung-Hoon; Oh, Bae Jun; Shim, Wooyoung; Choi, Jin Myung; Yoo, Dongkyeom; Hwang, Yong Hwa; Lee, Jung Hee; Lee, Dong Yun; Kim, Jae Hyeon

    2015-06-01

    There is a clinical need for an alternative labeling agent for magnetic resonance imaging (MRI) in islet transplantation. We aimed to evaluate the feasibility of islet MRI using ferumoxytol, which is the only clinically-available ultrasmall superparamagnetic iron oxide. We compared islet function and viability of control islets and islets labeled with ferumoxytol and/or a heparin-protamine complex (HPF). Efficacy of ferumoxytol labeling was assessed in both ex vivo and in vivo models. Labeling for 48 h with HPF, but not up to 800 μg/mL ferumoxytol, deranged ex vivo islet viability and function. The T2∗ relaxation time was optimal when islets were labeled with 800 μg/mL of ferumoxytol for 48 h. Prussian blue stain, iron content assay, transmission electron microscopy (TEM) supported internalization of ferumoxytol particles. However, the labeling intensity in the ex vivo MRI of islets labeled with ferumoxytol was much weaker than that of islets labeled with ferucarbotran. In syngeneic intraportal islet transplantation, there was a correlation between the total area of visualized islets and the transplanted islet mass. In conclusion, islet MRI using ferumoxytol was feasible in terms of in vitro and in vivo efficacy and safety. However, the weak labeling efficacy is still a hurdle for the clinical application. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Striated Muscle as Implantation Site for Transplanted Pancreatic Islets

    Directory of Open Access Journals (Sweden)

    Daniel Espes

    2011-01-01

    Full Text Available Islet transplantation is an attractive treatment for selected patients with brittle type 1 diabetes. In the clinical setting, intraportal transplantation predominates. However, due to extensive early islet cell death, the quantity of islets needed to restore glucose homeostasis requires in general a minimum of two donors. Moreover, the deterioration of islet function over time results in few insulin-independent patients after five-year followup. Specific obstacles to the success of islet transplantation include site-specific concerns for the liver such as the instant blood mediated inflammatory reaction, islet lipotoxicity, low oxygen tension, and poor revascularization, impediments that have led to the developing interest for alternative implantation sites over recent years. Within preclinical settings, several alternative sites have now been investigated and proven favorable in various aspects. Muscle is considered a very promising site and has physiologically properties and technical advantages that could make it optimal for islet transplantation.

  20. Islet transplantation: the quest for an ideal source

    International Nuclear Information System (INIS)

    Younes, Nidal A.; Nothias, J.; Garfinkel, Marc R.

    2008-01-01

    The progress of islet transplantation as a new therapy for patients with diabetes mellitus depends directly upon the development of efficient and practical immunoisolation methods for the supply of sufficient quantities of islet cells. Without these methods, large scale clinical application of this therapy would be impossible. Two eras of advances can be identified in the development of islet transplantation. The first was an era of experimental animal and human research that centered on islet isolation procedures and transplantation in different species as evidence that transplanted islets have the capability to reverse diabetes. The second was the era of Edmonton protocol, when the focus became the standardization of isolation procedures and introduction of new immunosuppressive drugs to maintain human allograft transplantation. The quest for an alternative source for islets (xenographs, stem cells and cell cultures) to overcome the shortage of human islets was an important issue during these eras. This paper reviews the history of islet transplantation and the current procedures in human allotransplantation, as well as different types of immunoisolation methods. It explores novel approaches to enhancing transplantation site vascularity and islet cell function, whereby future immunoisolation technology could offer additional therapeutic advantages to human islet allotransplantation. (author)

  1. In Vivo Imaging of Transplanted Pancreatic Islets

    Directory of Open Access Journals (Sweden)

    Donghee Kim

    2018-01-01

    Full Text Available The beta-cells in the islets of Langerhans in the pancreas secrete insulin and play an important role in glucose homeostasis. Diabetes, characterized by hyperglycemia, results from an absolute or a relative deficiency of the pancreatic beta-cell mass. Islet transplantation has been considered to be a useful therapeutic approach, but it is largely unsuccessful because most of the transplanted islets are lost in the early stage of transplantation. To evaluate the efficacy of intervention methods for the improvement of islet survival, monitoring of the functional islet mass is needed. Various techniques to image and track transplanted islets have been investigated to assess islets after transplantation. In this review, recent progresses in imaging methods to visualize islets are discussed.

  2. International workshop: islet transplantation without borders enabling islet transplantation in Greece with international collaboration and innovative technology.

    Science.gov (United States)

    Papas, Klearchos K; Karatzas, Theodore; Berney, Thierry; Minor, Thomas; Pappas, Paris; Pattou, François; Shaw, James; Toso, Christian; Schuurman, Henk-Jan

    2013-01-01

    Recently, initiatives have been undertaken to establish an islet transplantation program in Athens, Greece. A major hurdle is the high cost associated with the establishment and maintenance of a clinical-grade islet manufacturing center. A collaboration was established with the University Hospitals of Geneva, Switzerland, to enable remote islet cell manufacturing with an established and validated fully operational team. However, remote islet manufacturing requires shipment of the pancreas from the procurement to the islet manufacturing site (in this case from anywhere in Greece to Geneva) and then shipment of the islets from the manufacturing site to the transplant site (from Geneva to Athens). To address challenges related to cold ischemia time of the pancreas and shipment time of islets, a collaboration was initiated with the University of Arizona, Tucson, USA. An international workshop was held in Athens, December 2011, to mark the start of this collaborative project. Experts in the field presented in three main sessions: (i) islet transplantation: state-of-the-art and the "network approach"; (ii) technical aspects of clinical islet transplantation and outcomes; and (iii) islet manufacturing - from the donated pancreas to the islet product. This manuscript presents a summary of the workshop. © 2013 John Wiley & Sons A/S.

  3. Extensive Loss of Islet Mass Beyond the First Day After Intraportal Human Islet Transplantation in a Mouse Model.

    Science.gov (United States)

    Liljebäck, Hanna; Grapensparr, Liza; Olerud, Johan; Carlsson, Per-Ola

    2016-01-01

    Clinical islet transplantation is characterized by a progressive deterioration of islet graft function, which renders many patients once again dependent on exogenous insulin administration within a couple of years. In this study, we aimed to investigate possible engraftment factors limiting the survival and viability of experimentally transplanted human islets beyond the first day after their transplantation to the liver. Human islets were transplanted into the liver of nude mice and characterized 1 or 30 days after transplantation by immunohistochemistry. The factors assessed were endocrine mass, cellular death, hypoxia, vascular density and amyloid formation in the transplanted islets. One day posttransplantation, necrotic cells, as well as apoptotic cells, were commonly observed. In contrast to necrotic death, apoptosis rates remained high 1 month posttransplantation, and the total islet mass was reduced by more than 50% between 1 and 30 days posttransplantation. Islet mass at 30 days posttransplantation correlated negatively to apoptotic death. Vascular density within the transplanted islets remained less than 30% of that in native human islets up to 30 days posttransplantation and was associated with prevailing hypoxia. Amyloid formation was rarely observed in the 1-day-old transplants, but was commonly observed in the 30-day-old islet transplants. We conclude that substantial islet cell death occurs beyond the immediate posttransplantation phase, particularly through apoptotic events. Concomitant low vascularization with prevailing hypoxia and progressive amyloid development was observed in the human islet grafts. Strategies to improve engraftment at the intraportal site or change of implantation site in the clinical setting are needed.

  4. A novel subcutaneous site of islet transplantation superior to the liver.

    Science.gov (United States)

    Yasunami, Yohichi; Nakafusa, Yuki; Nitta, Naoyoshi; Nakamura, Masafumi; Goto, Masafumi; Ono, Junko; Taniguchi, Masaru

    2018-03-08

    Islet transplantation is an attractive treatment for patients with insulin-dependent diabetes mellitus, and currently the liver is the favored transplantation site. However, an alternative site is desirable because of the low efficiency of hepatic transplantation, requiring 2-3 donors for a single recipient, and because the transplanted islets cannot be accessed or retrieved. We developed a novel procedure of islet transplantation to the inguinal subcutaneous white adipose tissue (ISWAT) of mice and described functional and morphological characteristics of transplanted syngeneic islets. Also, it was determined whether islet allograft rejection in the ISWAT can be prevented by immunosuppressive agents. Furthermore, it was examined whether human islets function when grafted in this particular site of immune-deficient mice. In this site, transplanted islets are engrafted as clusters and function to reverse STZ-induced diabetes in mice. Importantly, transplanted islets can be visualized by CT and are easily retrievable, and allograft rejection is preventable by blockade of co-stimulatory signals. Of much importance, the efficiency of islet transplantation in this site is superior to the liver, in which hyperglycemia of diabetic recipient mice is ameliorated after transplantation of 200 syngeneic islets (the islet number yielded from 1 mouse pancreas) to the ISWAT but not to the liver. Furthermore, human islets transplanted in this particular site function to reverse diabetes in immune-deficient mice. Thus, the ISWAT is superior to the liver as the site of islet transplantation, which may lead to improved outcome of clinical islet transplantation.

  5. Is islet transplantation a realistic approach to curing diabetes?

    Science.gov (United States)

    Jin, Sang-Man; Kim, Kwang-Won

    2017-01-01

    Since the report of type 1 diabetes reversal in seven consecutive patients by the Edmonton protocol in 2000, pancreatic islet transplantation has been reappraised based on accumulated clinical evidence. Although initially expected to therapeutically target long-term insulin independence, islet transplantation is now indicated for more specific clinical benefits. With the long-awaited report of the first phase 3 clinical trial in 2016, allogeneic islet transplantation is now transitioning from an experimental to a proven therapy for type 1 diabetes with problematic hypoglycemia. Islet autotransplantation has already been therapeutically proven in chronic pancreatitis with severe abdominal pain refractory to conventional treatments, and it holds promise for preventing diabetes after partial pancreatectomy due to benign pancreatic tumors. Based on current evidence, this review focuses on islet transplantation as a realistic approach to treating diabetes.

  6. Prediction of Marginal Mass Required for Successful Islet Transplantation

    Science.gov (United States)

    Papas, Klearchos K.; Colton, Clark K.; Qipo, Andi; Wu, Haiyan; Nelson, Rebecca A.; Hering, Bernhard J.; Weir, Gordon C.; Koulmanda, Maria

    2013-01-01

    Islet quality assessment methods for predicting diabetes reversal (DR) following transplantation are needed. We investigated two islet parameters, oxygen consumption rate (OCR) and OCR per DNA content, to predict transplantation outcome and explored the impact of islet quality on marginal islet mass for DR. Outcomes in immunosuppressed diabetic mice were evaluated by transplanting mixtures of healthy and purposely damaged rat islets for systematic variation of OCR/DNA over a wide range. The probability of DR increased with increasing transplanted OCR and OCR/DNA. On coordinates of OCR versus OCR/DNA, data fell into regions in which DR occurred in all, some, or none of the animals with a sharp threshold of around 150-nmol/min mg DNA. A model incorporating both parameters predicted transplantation outcome with sensitivity and specificity of 93% and 94%, respectively. Marginal mass was not constant, depended on OCR/DNA, and increased from 2,800 to over 100,000 islet equivalents/kg body weight as OCR/DNA decreased. We conclude that measurements of OCR and OCR/DNA are useful for predicting transplantation outcome in this model system, and OCR/DNA can be used to estimate the marginal mass required for reversing diabetes. Because human clinical islet preparations in a previous study had OCR/DNA values in the range of 100–150-nmol/min mg DNA, our findings suggest that substantial improvement in transplantation outcome may accompany increasedOCR/DNAin clinical islet preparations. PMID:20233002

  7. Encapsulated Islet Transplantation: Where Do We Stand?

    Science.gov (United States)

    Vaithilingam, Vijayaganapathy; Bal, Sumeet; Tuch, Bernard E

    2017-01-01

    Transplantation of pancreatic islets encapsulated within immuno-protective microcapsules is a strategy that has the potential to overcome graft rejection without the need for toxic immunosuppressive medication. However, despite promising preclinical studies, clinical trials using encapsulated islets have lacked long-term efficacy, and although generally considered clinically safe, have not been encouraging overall. One of the major factors limiting the long-term function of encapsulated islets is the host's immunological reaction to the transplanted graft which is often manifested as pericapsular fibrotic overgrowth (PFO). PFO forms a barrier on the capsule surface that prevents the ingress of oxygen and nutrients leading to islet cell starvation, hypoxia and death. The mechanism of PFO formation is still not elucidated fully and studies using a pig model have tried to understand the host immune response to empty alginate microcapsules. In this review, the varied strategies to overcome or reduce PFO are discussed, including alginate purification, altering microcapsule geometry, modifying alginate chemical composition, co-encapsulation with immunomodulatory cells, administration of pharmacological agents, and alternative transplantation sites. Nanoencapsulation technologies, such as conformal and layer-by-layer coating technologies, as well as nanofiber, thin-film nanoporous devices, and silicone based NanoGland devices are also addressed. Finally, this review outlines recent progress in imaging technologies to track encapsulated cells, as well as promising perspectives concerning the production of insulin-producing cells from stem cells for encapsulation.

  8. Posttransplant oxygen inhalation improves the outcome of subcutaneous islet transplantation: A promising clinical alternative to the conventional intrahepatic site.

    Science.gov (United States)

    Komatsu, H; Rawson, J; Barriga, A; Gonzalez, N; Mendez, D; Li, J; Omori, K; Kandeel, F; Mullen, Y

    2018-04-01

    Subcutaneous tissue is a promising site for islet transplantation, due to its large area and accessibility, which allows minimally invasive procedures for transplantation, graft monitoring, and removal of malignancies as needed. However, relative to the conventional intrahepatic transplantation site, the subcutaneous site requires a large number of islets to achieve engraftment success and diabetes reversal, due to hypoxia and low vascularity. We report that the efficiency of subcutaneous islet transplantation in a Lewis rat model is significantly improved by treating recipients with inhaled 50% oxygen, in conjunction with prevascularization of the graft bed by agarose-basic fibroblast growth factor. Administration of 50% oxygen increased oxygen tension in the subcutaneous site to 140 mm Hg, compared to 45 mm Hg under ambient air. In vitro, islets cultured under 140 mm Hg oxygen showed reduced central necrosis and increased insulin release, compared to those maintained in 45 mm Hg oxygen. Six hundred syngeneic islets subcutaneously transplanted into the prevascularized graft bed reversed diabetes when combined with postoperative 50% oxygen inhalation for 3 days, a number comparable to that required for intrahepatic transplantation; in the absence of oxygen treatment, diabetes was not reversed. Thus, we show oxygen inhalation to be a simple and promising approach to successfully establishing subcutaneous islet transplantation. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  9. Oxygenation of the Intraportally Transplanted Pancreatic Islet.

    Science.gov (United States)

    Suszynski, Thomas M; Avgoustiniatos, Efstathios S; Papas, Klearchos K

    2016-01-01

    Intraportal islet transplantation (IT) is not widely utilized as a treatment for type 1 diabetes. Oxygenation of the intraportally transplanted islet has not been studied extensively. We present a diffusion-reaction model that predicts the presence of an anoxic core and a larger partly functional core within intraportally transplanted islets. Four variables were studied: islet diameter, islet fractional viability, external oxygen partial pressure ( P ) (in surrounding portal blood), and presence or absence of a thrombus on the islet surface. Results indicate that an islet with average size and fractional viability exhibits an anoxic volume fraction (AVF) of 14% and a function loss of 72% at a low external P . Thrombus formation increased AVF to 30% and function loss to 92%, suggesting that the effect of thrombosis may be substantial. External P and islet diameter accounted for the greatest overall impact on AVF and loss of function. At our institutions, large human alloislets (>200 μ m diameter) account for ~20% of total islet number but ~70% of total islet volume; since most of the total transplanted islet volume is accounted for by large islets, most of the intraportal islet cells are likely to be anoxic and not fully functional.

  10. Oxygenation of the Intraportally Transplanted Pancreatic Islet

    Directory of Open Access Journals (Sweden)

    Thomas M. Suszynski

    2016-01-01

    Full Text Available Intraportal islet transplantation (IT is not widely utilized as a treatment for type 1 diabetes. Oxygenation of the intraportally transplanted islet has not been studied extensively. We present a diffusion-reaction model that predicts the presence of an anoxic core and a larger partly functional core within intraportally transplanted islets. Four variables were studied: islet diameter, islet fractional viability, external oxygen partial pressure (P (in surrounding portal blood, and presence or absence of a thrombus on the islet surface. Results indicate that an islet with average size and fractional viability exhibits an anoxic volume fraction (AVF of 14% and a function loss of 72% at a low external P. Thrombus formation increased AVF to 30% and function loss to 92%, suggesting that the effect of thrombosis may be substantial. External P and islet diameter accounted for the greatest overall impact on AVF and loss of function. At our institutions, large human alloislets (>200 μm diameter account for ~20% of total islet number but ~70% of total islet volume; since most of the total transplanted islet volume is accounted for by large islets, most of the intraportal islet cells are likely to be anoxic and not fully functional.

  11. Clinical islet isolation and transplantation outcomes with deceased cardiac death donors are similar to neurological determination of death donors.

    Science.gov (United States)

    Andres, Axel; Kin, Tatsuya; O'Gorman, Doug; Livingstone, Scott; Bigam, David; Kneteman, Norman; Senior, Peter; Shapiro, A M James

    2016-01-01

    In islet transplantation, deceased cardiac death (DCD) donation has been identified as a potential extended source. There are currently no studies comparing outcomes between these categories, and our goal was to compare islet isolation success rates and transplantation outcomes between DCD and neurological determination of death (NDD) donors. Islet isolations from 15 DCD and 418 NDD were performed in our centre between September 2008 and September 2014. Donor variables, islet yields, metabolic function of isolated isled and insulin requirements at 1-month post-transplant were compared. Compared to NDD, pancreata from DCD were more often procured locally and donors required less vasopressive support (P islet yields were similar between NDD and DCD (576 vs. 608 × 10(3) islet equivalent, P = 0.628 and 386 vs. 379, P = 0.881, respectively). The metabolic function was similar between NDD and DCD, as well as the mean decrease in insulin requirement at 1-month post-transplantation (NDD: 64.82%; DCD: 60.17% reduction, P = 0.517). These results support the broader use of DCD pancreata for islet isolation. A much larger DCD islet experience will be required to truly determine noninferiority of both short- and long-term outcomes. © 2015 Steunstichting ESOT.

  12. Pancreatic Islet Cell Transplantation: A new era in transplantation

    OpenAIRE

    Warnock, Garth L.; Rajotte, Ray V.

    1992-01-01

    Transplantation of insulin-producing tissue offers a physiologic approach to restoration of glycemic control. Whereas transplantation of vascularized pancreatic grafts has recently achieved encouraging results, pancreatic islet cell transplantation holds the promise of low morbidity and reduced requirements for agressive immunosuppression for recipients. Islet cell transplantation was recently demonstrated to induce euglycemia with insulin independence.

  13. Long-term outcomes of clinical transplantation of pancreatic islets with uncontrolled donors after cardiac death: a multicenter experience in Japan.

    Science.gov (United States)

    Anazawa, T; Saito, T; Goto, M; Kenmochi, T; Uemoto, S; Itoh, T; Yasunami, Y; Kenjo, A; Kimura, T; Ise, K; Tsuchiya, T; Gotoh, M

    2014-01-01

    Pancreatic islet transplantation has emerged as an effective treatment for type 1 diabetes mellitus, but its use is limited due to an insufficient supply of cadaveric pancreata. In Japan, uncontrolled donors after cardiac death (DCD) are not deemed to be suitable for whole-organ pancreatic transplantation, and can provide a source of pancreas for islet transplantation. However, the long-term outcomes and utility of uncontrolled DCD in the clinical setting remain controversial. Here, we summarize the long-term outcomes of islet transplantation employing uncontrolled DCD as reported to the Japan Islet Transplantation Registry. Sixty-four isolations and 34 transplantations of pancreatic islets were conducted in 18 subjects with type 1 diabetes mellitus under the cover of immunosuppression with basiliximab, sirolimus, and tacrolimus. All donors were uncontrolled DCD at the time of harvesting. The mean follow-up time was 76 months. Of the 18 recipients, 8, 4, and 6 recipients received 1, 2, and 3 islet infusions, respectively. Overall graft survivals (defined as a C-peptide level ≥0.3 ng/mL) were 72.2%, 44.4%, and 22.2% at 1, 2, and 5 years, respectively, whereas the corresponding graft survivals after multiple infusions were 90.0%, 70.0%, and 30.0%, respectively. Three of these recipients achieved insulin independence in 14, 79, and 215 days. HbA1c levels and the requirement of exogenous insulin were improved before loss of graft function. All recipients became free of severe hypoglycemia unawareness, however, at least 5 of 14 patients who had graft failure experienced recurrence of severe hypoglycemia after the loss of graft function. Islet transplantation from DCD can relieve glucose instability and problems with hypoglycemia when the graft is functioning. However, islets from uncontrolled DCD may be associated with reduced long-term graft survival. Further improvements in the clinical outcome by modification of islet isolation/transplantation protocols are

  14. OBSTACLES IN THE APPLICATION OF MICROENCAPSULATION IN ISLET TRANSPLANTATION

    NARCIS (Netherlands)

    DEVOS, P; WOLTERS, GHJ; FRITSCHY, WM; VANSCHILFGAARDE, R

    Several factors stand in the way of successful clinical transplantation of alginate-polylysine-alginate microencapsulated pancreatic islets. These obstacles can be classified into three categories. The first regards the technical aspects of the production process. Limiting factors are the

  15. Pancreatic Islet Transplantation

    Science.gov (United States)

    ... auto-transplantation is performed following total pancreatectomy—the surgical removal of the whole pancreas—in patients with severe and chronic, or long lasting, pancreatitis that cannot be managed by other treatments. This procedure is not considered experimental. Patients with ...

  16. Photoacoustic imaging of angiogenesis in subdermal islet transplant sites

    Science.gov (United States)

    Shi, Wei; Pawlick, Rena; Bruni, Antonio; Rafiei, Yasmin; Pepper, Andrew R.; Gala-Lopez, Boris; Choi, Min; Malcolm, Andrew; Zemp, Roger J.; Shapiro, A. M. James

    2016-03-01

    Exogenous insulin administration is the mainstay treatment therapy for patients with Type-1 diabetes mellitus (T1DM). However, for select patients, clinical islet transplantation is an alternative therapeutic treatment. In this procedure, islets are transplanted into the hepatic portal vein, and despite improved success within the last decade, obstacles are still associated with this approach. It has been discovered that the subcutaneous space may be an effective alternative site for islet transplantation, and may provide advantages of easy access and potential for simple monitoring. The ability to monitor islet viability and the transplant microenvironment may be key to future success in islet transplantation. A subcutaneous device-less technique has been developed to facilitate angiogenesis in the islet transplant site, however, a method for monitoring the potential engraftment site have yet to be explored fully. Here we demonstrate the ability to track angiogenesis in mice with 1, 2, 3 and 4 weeks post-catheter implant on both sides of the abdomen using a FujiFilm VisualSonics Vevo-LAZR system. Quantitative analysis on vessel densities exhibited gradual vessel growth successfully induced by catheter implantation. Our study demonstrates the ability of employing photoacoustic and micro-ultrasound imaging to track angiogenesis around the catheter site prior to islet transplantation.

  17. Introducing a New Experimental Islet Transplantation Model using Biomimetic Hydrogel and a Simple High Yield Islet Isolation Technique.

    Science.gov (United States)

    Mohammadi Ayenehdeh, Jamal; Niknam, Bahareh; Hashemi, Seyed Mahmoud; Rahavi, Hossein; Rezaei, Nima; Soleimani, Masoud; Tajik, Nader

    2017-07-01

    Islet transplantation could be an ideal alternative treatment to insulin therapy for type 1 diabetes Mellitus (T1DM). This clinical and experimental field requires a model that covers problems such as requiring a large number of functional and viable islets, the optimal transplantation site, and the prevention of islet dispersion. Hence, the methods of choice for isolation of functional islets and transplantation are crucial. The present study has introduced an experimental model that overcomes some critical issues in islet transplantation, including in situ pancreas perfusion by digestive enzymes through common bile duct. In comparison with conventional methods, we inflated the pancreas in Petri dishes with only 1 ml collagenase type XI solution, which was followed by hand-picking isolation or Ficoll gradient separation to purify the islets. Then we used a hydrogel composite in which the islets were embedded and transplanted into the peritoneal cavity of the streptozotocin-induced diabetic C57BL/6 mice. As compared to the yield of the classical methods, in our modified technique, the mean yield of isolation was about 130-200 viable islets/mouse pancreas. In vitro glucose-mediated insulin secretion assay indicated an appropriate response in isolated islets. In addition, data from in vivo experiments revealed that the allograft remarkably maintained blood glucose levels under 400 mg/dl and hydrogel composite prevents the passage of immune cells. In the model presented here, the rapid islet isolation technique and the application of biomimetic hydrogel wrapping of islets could facilitate islet transplantation procedures.

  18. Intraportal islet transplantation: the impact of the liver microenvironment.

    Science.gov (United States)

    Delaune, Vaihere; Berney, Thierry; Lacotte, Stéphanie; Toso, Christian

    2017-03-01

    The portal vein remains the preferred site for pancreatic islet transplantation due to its easy access and low morbidity. However, despite great progress in isolation and transplantation protocols over the past few years, it is still associated with the early loss of some 50-70% of transplanted islets. The complex liver microenvironment itself presumably plays an important role in this loss. The present review focuses on the specifics of the liver microenvironment, notably the localized hepatic ischemia/reperfusion injury following transplantation, the low oxygenation of the portal vein, the instant blood-mediated inflammatory reaction, the endogenous liver immune system, and the gut-liver axis, and how they can each have an impact on the transplanted islets. It identifies the potential, or already applied, clinical interventions for improving intraportal islet survival, and pinpoints those promising areas still lacking preclinical research. Future interventions on clinical intraportal islet transplantation need to take into account the global context of the liver microenvironment, with multi-point interventions being most likely to improve early islet survival and engraftment. © 2017 The Authors. Transplant International published by John Wiley & Sons Ltd on behalf of Steunstichting ESOT.

  19. Evaluation of Porcine Pancreatic Islets Transplanted in the Kidney Capsules of Diabetic Mice Using a Clinically Approved Superparamagnetic Iron Oxide (SPIO) and a 1.5T MR Scanner

    International Nuclear Information System (INIS)

    Kim, Hoe Suk; Kim, Hyoung Su; Park, Kyong Soo; Moon, Woo Kyung

    2010-01-01

    To evaluate transplanted porcine pancreatic islets in the kidney capsules of diabetic mice using a clinically approved superparamagnetic iron oxide (SPIO) and a 1.5T MR scanner. Various numbers of porcine pancreatic islets labeled with Resovist, a carboxydextran-coated SPIO, were transplanted into the kidney capsules of normal mice and imaged with a 3D FIESTA sequence using a 1.5T clinical MR scanner. Labeled (n = 3) and unlabeled (n = 2) islets were transplanted into the kidney capsules of streptozotocin-induced diabetic mice. Blood glucose levels and MR signal intensities were monitored for 30 days post-transplantation. There were no significant differences in viability or insulin secretion between labeled and unlabeled islets. A strong correlation (γ 2 > 0.94) was evident between the number of transplanted islets and T 2 relaxation times quantified by MRI. Transplantation with labeled or unlabeled islets helped restore normal sustained glucose levels in diabetic mice, and nephrectomies induced the recurrence of diabetes. The MR signal intensity of labeled pancreatic islets decreased by 80% over 30 days. The transplantation of SPIO-labeled porcine islets into the kidney capsule of diabetic mice allows to restore normal glucose levels, and these islets can be visualized and quantified using a 1.5T clinical MR scanner

  20. Organ culture studies for pancreatic islet transplantation

    International Nuclear Information System (INIS)

    Reemtsma, K.; Weber, C.J.; Pi-Sunyer, F.X.; Lerner, R.; Zimmerman, E.; Hardy, M.A.

    1979-01-01

    Data support the usefulness of tissue culture in isolation and preservation of islets prior to transplantation. Rodent islet viability in culture was demonstrated histologically and by functional analyses of hormone production. For reasons that remain to be defined, acinar cells disappeared rapidly in tissue culture, yielding an implant preparation relatively rich in islets and devoid of pancreatic exocrine elements. Isografts of cultured and noncultured islets were well tolerated intraperitoneally and intramuscularly; and prompt and lasting reversal of short- and long-standing experimental diabetes was observed regularly. In vitro studies of rodent islet viability after immunosuppressive treatment of donors or islet cultures showed insulin production comparable to that of control experiments, suggesting that immunologic modification of donors or islets might be feasible in eventual human islet allotransplantation

  1. Considerations for successful transplantation of encapsulated pancreatic islets

    NARCIS (Netherlands)

    de Vos, P; Hamel, AF; Tatarkiewicz, K

    Encapsulation of pancreatic islets allows for transplantion in the absence of immunosuppression. The technology is based on the principle that transplanted tissue is protected for the host immune system by an artificial membrane. Encapsulation offers a solution to the shortage of donors in clinical

  2. Who Should Be Considered for Islet Transplantation Alone?

    Science.gov (United States)

    Othonos, Nantia; Choudhary, Pratik

    2017-04-01

    Episodic hypoglycemia is an almost inevitable consequence of exogenous insulin treatment of type 1 diabetes, and in up to 30% of patients, this can lead to impaired awareness of hypoglycemia. This predisposes to recurrent severe hypoglycemia and has a huge impact on quality of life. Although many patients can get resolution of severe hypoglycemia through novel education and technology, some patients continue to have ongoing life-threatening hypoglycemia. Islet transplantation offers an alternative therapeutic option for these patients, in whom these conventional approaches have been unsuccessful. This review discusses the selection process of identifying suitable candidates based on recent clinical data. Results from studies of islet transplantation suggest the optimal recipient characteristics for successful islet transplantation include age >35 years, insulin requirements 85 kg. Islet transplantation can completely resolve hypoglycemia and near-normalize glucose levels, achieving insulin independence for a limited period of time in up to 40% of patients. The selection of appropriate candidates, optimizing donor selection, the use of an optimized protocol for islet cell extraction, and immunosuppression therapy have been proved to be the key criteria for a favorable outcome in islet transplantation.

  3. Long-term effects of islet transplantation.

    Science.gov (United States)

    Holmes-Walker, D Jane; Kay, Thomas W H

    2016-10-01

    Islet transplantation has made great progress in recent years. This is a remarkable technical feat but raises the question of what the long-term benefits and risks are for type I diabetes recipients. Graft survival continues to improve, and recent multicenter studies show that islet transplantation is particularly effective to prevent hypoglycemic events even in those who do not become insulin-independent and to achieve excellent glycemic control. Concerns include histocompatability leucocyte antigen (HLA) sensitization and other risks including from immunosuppression that islet transplantation shares with other forms of allotransplantation. Reversal of hypoglycemia unawareness and protection from severe hypoglycemia events are two of the main benefits of islet transplantation and they persist for the duration of graft function. Islet transplantation compares favorably with other therapies for those with hypoglycemia unawareness, although new technologies have not been tested head-to-head with transplantation. HLA sensitization increases with time after transplantation especially if immunosuppression is ceased and is a risk for those who may require future transplantation as well as being associated with loss of graft function.

  4. Pharmacological strategies for protection of extrahepatic islet transplantation.

    Science.gov (United States)

    Omori, K; Komatsu, H; Rawson, J; Mullen, Y

    2015-06-01

    The safety and effectiveness of islet transplantation has been proven through world-wide trials. However, acute and chronic islet loss has hindered the ultimate objective of becoming a widely used treatment option for type 1 diabetes. A large islet loss is attributed, in part, to the liver being a less-than-optimal site for transplantation. Over half of the transplanted islets are destroyed shortly after transplantation due to direct exposure to blood and non-specific inflammation. Successfully engrafted islets are continuously exposed to the liver micro-environment, a unique immune system, low oxygen tension, toxins and high glucose, which is toxic to islets, leading to premature islet dysfunction/death. Investigations have continued to search for alternate sites to transplant islets that provide a better environment for prolonged function and survival. This article gathers courses and conditions that lead to islet loss, from organ procurement through islet transplantation, with special emphasis on hypoxia, oxidative stress, and antigen non-specific inflammation, and reviews strategies using pharmacological agents that have shown effectiveness in protecting islets, including a new treatment approach utilizing siRNA. Pharmacological agents that support islet survival and promote β-cell proliferation are also included. Treatment of donor pancreata and/or islets with these agents should increase the effectiveness of islets transplanted into extrahepatic sites. Furthermore, the development of methods designed to release these agents over an extended period, will further increase their efficacy. This requires the combined efforts of both islet transplant biologists and bioengineers.

  5. Serum Cytokines as Biomarkers in Islet Cell Transplantation for Type 1 Diabetes

    NARCIS (Netherlands)

    van der Torren, Cornelis R; Verrijn Stuart, Annemarie A; Lee, DaHae; Meerding, Jenny; van de Velde, Ursule; Pipeleers, Daniel; Gillard, Pieter; Keymeulen, Bart; de Jager, Wilco; Roep, Bart O

    2016-01-01

    BACKGROUND: Islet cell transplantation holds a potential cure for type 1 diabetes, but many islet recipients do not reach long-lasting insulin independence. In this exploratory study, we investigated whether serum cytokines, chemokines and adipokines are associated with the clinical outcome of islet

  6. Islet oxygen consumption rate (OCR) dose predicts insulin independence for first clinical islet allotransplants

    Science.gov (United States)

    Kitzmann, JP; O’Gorman, D; Kin, T; Gruessner, AC; Senior, P; Imes, S; Gruessner, RW; Shapiro, AMJ; Papas, KK

    2014-01-01

    Human islet allotransplant (ITx) for the treatment of type 1 diabetes is in phase III clinical registration trials in the US and standard of care in several other countries. Current islet product release criteria include viability based on cell membrane integrity stains, glucose stimulated insulin release (GSIR), and islet equivalent (IE) dose based on counts. However, only a fraction of patients transplanted with islets that meet or exceed these release criteria become insulin independent following one transplant. Measurements of islet oxygen consumption rate (OCR) have been reported as highly predictive of transplant outcome in many models. In this paper we report on the assessment of clinical islet allograft preparations using islet oxygen consumption rate (OCR) dose (or viable IE dose) and current product release assays in a series of 13 first transplant recipients. The predictive capability of each assay was examined and successful graft function was defined as 100% insulin independence within 45 days post-transplant. Results showed that OCR dose was most predictive of CTO. IE dose was also highly predictive, while GSIR and membrane integrity stains were not. In conclusion, OCR dose can predict CTO with high specificity and sensitivity and is a useful tool for evaluating islet preparations prior to clinical ITx. PMID:25131089

  7. Islet alloautotransplantation: Allogeneic pancreas transplantation followed by transplant pancreatectomy and islet transplantation.

    Science.gov (United States)

    Nijhoff, M F; Dubbeld, J; van Erkel, A R; van der Boog, P J M; Rabelink, T J; Engelse, M A; de Koning, E J P

    2018-04-01

    Simultaneous pancreas-kidney (SPK) transplantation is an important treatment option for patients with type 1 diabetes (T1D) and end-stage renal disease (ESRD). Due to complications, in up to 10% of patients, allograft pancreatectomy is necessary shortly after transplantation. Usually the donor pancreas is discarded. Here, we report on a novel procedure to rescue endocrine tissue after allograft pancreatectomy. A 39-year-old woman with T1D and ESRD who had undergone SPK transplantation required emergency allograft pancreatectomy due to bleeding at the vascular anastomosis. Islets were isolated from the removed pancreas allograft, and almost 480 000 islet equivalents were infused into the portal vein. The patient recovered fully. After 3 months, near-normal mixed meal test (fasting glucose 7.0 mmol/L, 2-hour glucose 7.5 mmol/L, maximal stimulated C-peptide 3.25 nmol/L, without insulin use in the preceding 36 hours) was achieved. Glycated hemoglobin while taking a low dose of long-acting insulin was 32.7 mmol/mol hemoglobin (5.3%). When a donor pancreas is lost after transplantation, rescue β cell therapy by islet alloautotransplantation enables optimal use of scarce donor pancreata to optimize glycemic control without additional HLA alloantigen exposure. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  8. A macroporous heparin-releasing silk fibroin scaffold improves islet transplantation outcome by promoting islet revascularisation and survival.

    Science.gov (United States)

    Mao, Duo; Zhu, Meifeng; Zhang, Xiuyuan; Ma, Rong; Yang, Xiaoqing; Ke, Tingyu; Wang, Lianyong; Li, Zongjin; Kong, Deling; Li, Chen

    2017-09-01

    Islet transplantation is considered the most promising therapeutic option with the potential to cure diabetes. However, efficacy of current clinical islet transplantation is limited by long-term graft dysfunction and attrition. We have investigated the therapeutic potential of a silk fibroin macroporous (SF) scaffold for syngeneic islet transplantation in diabetic mice. The SF scaffold was prepared via lyophilisation, which enables incorporation of active compounds including cytokines, peptide and growth factors without compromising their biological activity. For the present study, a heparin-releasing SF scaffold (H-SF) in order to evaluate the versatility of the SF scaffold for biological functionalisation. Islets were then co-transplanted with H-SF or SF scaffolds in the epididymal fat pad of diabetic mice. Mice from both H-SF and SF groups achieved 100% euglycaemia, which was maintained for 1year. More importantly, the H-SF-islets co-transplantation led to more rapid reversal of hyperglycaemia, complete normalisation of glucose responsiveness and lower long-term blood glucose levels. This superior transplantation outcome is attributable to H-SF-facilitated islet revascularisation and cell proliferation since significant increase of islet endocrine and endothelial cells proliferation was shown in grafts retrieved from H-SF-islets co-transplanted mice. Better intra-islet vascular reformation was also evident, accompanied by VEGF upregulation. In addition, when H-SF was co-transplanted with islets extracted from vegfr2-luc transgenic mice in vivo, sustained elevation of bioluminescent signal that corresponds to vegfr2 expression was collected, implicating a role of heparin-dependent activation of endogenous VEGF/VEGFR2 pathway in promoting islet revascularisation and proliferation. In summary, the SF scaffolds provide an open platform as scaffold development for islet transplantation. Furthermore, given the pro-angiogenic, pro-survival and minimal post-transplantation

  9. Nonhuman Primate Models of Type 1 Diabetes Mellitus for Islet Transplantation

    Directory of Open Access Journals (Sweden)

    Haitao Zhu

    2014-01-01

    Full Text Available Islet transplantation is an attractive treatment of type 1 diabetes mellitus (T1DM. Animal models of diabetes mellitus (DM contribute a lot to the experimental studies of islet transplantation and to evaluations of isolated islet grafts for future clinical applications. Diabetic nonhuman primates (NHPs represent the suitable models of DMs to better evaluate the effectiveness of islet transplantation, to assess new strategies for controlling blood glucose (BG, relieving immune rejection, or prolonging islet survival, and eventually to translate the preclinical data into tangible clinical practice. This review introduces some NHP models of DM, clarifies why and how the models should be used, and elucidates the usefulness and limitations of the models in islet transplantation.

  10. Islet cell transplantation for the treatment of type 1 diabetes: recent advances and future challenges

    Directory of Open Access Journals (Sweden)

    Bruni A

    2014-06-01

    Full Text Available Anthony Bruni, Boris Gala-Lopez, Andrew R Pepper, Nasser S Abualhassan, AM James Shapiro Clinical Islet Transplant Program and Department of Surgery, University of Alberta, Edmonton, AB, Canada Abstract: Islet transplantation is a well-established therapeutic treatment for a subset of patients with complicated type I diabetes mellitus. Prior to the Edmonton Protocol, only 9% of the 267 islet transplant recipients since 1999 were insulin independent for >1 year. In 2000, the Edmonton group reported the achievement of insulin independence in seven consecutive patients, which in a collaborative team effort propagated expansion of clinical islet transplantation centers worldwide in an effort to ameliorate the consequences of this disease. To date, clinical islet transplantation has established improved success with insulin independence rates up to 5 years post-transplant with minimal complications. In spite of marked clinical success, donor availability and selection, engraftment, and side effects of immunosuppression remain as existing obstacles to be addressed to further improve this therapy. Clinical trials to improve engraftment, the availability of insulin-producing cell sources, as well as alternative transplant sites are currently under investigation to expand treatment. With ongoing experimental and clinical studies, islet transplantation continues to be an exciting and attractive therapy to treat type I diabetes mellitus with the prospect of shifting from a treatment for some to a cure for all. Keywords: islet transplantation, type I diabetes mellitus, Edmonton Protocol, engraftment, immunosuppression

  11. Islet transplantation using donors after cardiac death: report of the Japan Islet Transplantation Registry.

    Science.gov (United States)

    Saito, Takuro; Gotoh, Mitsukazu; Satomi, Susumu; Uemoto, Shinji; Kenmochi, Takashi; Itoh, Toshinori; Kuroda, Yoshikazu; Yasunami, Youichi; Matsumoto, Shnichi; Teraoka, Satoshi

    2010-10-15

    This report summarizes outcomes of islet transplantation employing donors after cardiac death (DCD) between 2004 and 2007 as reported to the Japan Islet Transplantation Registry. Sixty-five islet isolations were performed for 34 transplantations in 18 patients with insulin-dependent diabetes mellitus, including two patients who had prior kidney transplantation. All but one donor (64/65) was DCD at the time of harvesting. Factors influencing criteria for islet release included duration of low blood pressure of the donor, cold ischemic time, and usage of Kyoto solution for preservation. Multivariate analysis selected usage of Kyoto solution as most important. Of the 18 recipients, 8, 4, and 6 recipients received 1, 2, and 3 islet infusions, respectively. Overall graft survival defined as C-peptide level more than or equal to 0.3 ng/mL was 76.5%, 47.1%, and 33.6% at 1, 2, and 3 years, respectively, whereas corresponding graft survival after multiple transplantations was 100%, 80.0%, and 57.1%, respectively. All recipients remained free of severe hypoglycemia while three achieved insulin independence for 14, 79, and 215 days. HbA1c levels and requirement of exogenous insulin were significantly improved in all patients. Islet transplantation employing DCD can ameliorate severe hypoglycemic episodes, significantly improve HbA1c levels, sustain significant levels of C-peptide, and achieve insulin independence after multiple transplantations. Thus, DCD can be an important resource for islet transplantation if used under strict releasing criteria and in multiple transplantations, particularly in countries where heart-beating donors are not readily available.

  12. The role of endothelial cells on islet function and revascularization after islet transplantation.

    Science.gov (United States)

    Del Toro-Arreola, Alicia; Robles-Murillo, Ana Karina; Daneri-Navarro, Adrian; Rivas-Carrillo, Jorge David

    2016-01-02

    Islet transplantation has become a widely accepted therapeutic option for selected patients with type 1 diabetes mellitus. However, in order to achieve insulin independence a great number of islets are often pooled from 2 to 4 pancreata donors. Mostly, it is due to the massive loss of islets immediately after transplant. The endothelium plays a key role in the function of native islets and during the revascularization process after islet transplantation. However, if a delayed revascularization occurs, even the remaining islets will also undergo to cell death and late graft dysfunction. Therefore, it is essential to understand how the signals are released from endothelial cells, which might regulate both differentiation of pancreatic progenitors and thereby maintenance of the graft function. New strategies to facilitate islet engraftment and a prompt revascularization could be designed to intervene and might lead to improve future results of islet transplantation.

  13. Pediatric pancreas transplantation, including total pancreatectomy with islet autotransplantation.

    Science.gov (United States)

    Bondoc, Alexander J; Abu-El-Haija, Maisam; Nathan, Jaimie D

    2017-08-01

    Unlike other solid-organ transplants, whole pancreas transplantation in children is relatively rare, and it occurs more frequently in the context of multivisceral or composite organ transplantation. Because children only infrequently suffer severe sequelae of type 1 diabetes mellitus, pancreas transplantation is rarely indicated in the pediatric population. More commonly, pediatric pancreas transplant occurs in the setting of incapacitating acute recurrent or chronic pancreatitis, specifically islet autotransplantation after total pancreatectomy. In this clinical scenario, total pancreatectomy removes the nidus of chronic pain and debilitation, while autologous islet transplantation aims to preserve endocrine function. The published experiences with pediatric total pancreatectomy with islet autotransplantation (TPIAT) in children has demonstrated excellent outcomes including liberation from chronic opioid use, as well as improved mental and physical quality of life with good glycemic control. Given the complexity of the operation, risk of postoperative complication, and long-term physiologic changes, appropriate patient selection and comprehensive multidisciplinary care teams are critical to ensuring optimal outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. A novel method for murine intrahepatic islet transplantation via cecal vein.

    Science.gov (United States)

    Byun, Nari; Kim, Hyun-Je; Min, Byoung-Hoon; Shin, Jun-Seop; Yoon, Il-Hee; Kim, Jong-Min; Kim, Yong-Hee; Park, Chung-Gyu

    2015-12-01

    Islet transplantation is one of the most beneficial treatment modality to treat type 1 diabetic patients with frequent hypoglycemic unawareness. In clinical setting, human islets are infused via portal vein and are settled in the end-portal venules in the liver. However, mouse islets are transplanted into kidney subcapsule or liver through direct portal vein. These conventional transplantation methods have several drawbacks such as different physiological environments around the transplanted islets in kidney subcapsule from the liver and high mortality rate in direct portal vein approach. In this study, we introduced murine intrahepatic islet transplantation method via cecal vein to have the same surgical operation route in humans as well as guaranteeing low mortality rate after islet transplantation. With this protocol, consistent normoglycemia can be obtained in diabetic mice, while keeping operation-related mortality extremely low. This approach with easier accessibility and low mortality will make murine intrahepatic islet transplantation a useful model for studying immunological mechanisms such as strong innate and adaptive immune responses that occur in human islet transplantation. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Enhancing human islet transplantation by localized release of trophic factors from PLG scaffolds.

    Science.gov (United States)

    Hlavaty, K A; Gibly, R F; Zhang, X; Rives, C B; Graham, J G; Lowe, W L; Luo, X; Shea, L D

    2014-07-01

    Islet transplantation represents a potential cure for type 1 diabetes, yet the clinical approach of intrahepatic delivery is limited by the microenvironment. Microporous scaffolds enable extrahepatic transplantation, and the microenvironment can be designed to enhance islet engraftment and function. We investigated localized trophic factor delivery in a xenogeneic human islet to mouse model of islet transplantation. Double emulsion microspheres containing exendin-4 (Ex4) or insulin-like growth factor-1 (IGF-1) were incorporated into a layered scaffold design consisting of porous outer layers for islet transplantation and a center layer for sustained factor release. Protein encapsulation and release were dependent on both the polymer concentration and the identity of the protein. Proteins retained bioactivity upon release from scaffolds in vitro. A minimal human islet mass transplanted on Ex4-releasing scaffolds demonstrated significant improvement and prolongation of graft function relative to blank scaffolds carrying no protein, and the release profile significantly impacted the duration over which the graft functioned. Ex4-releasing scaffolds enabled better glycemic control in animals subjected to an intraperitoneal glucose tolerance test. Scaffolds releasing IGF-1 lowered blood glucose levels, yet the reduction was insufficient to achieve euglycemia. Ex4-delivering scaffolds provide an extrahepatic transplantation site for modulating the islet microenvironment to enhance islet function posttransplant. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.

  16. Construction of EMSC-islet co-localizing composites for xenogeneic porcine islet transplantation.

    Science.gov (United States)

    Kim, Jung-Sik; Chung, Hyunwoo; Byun, Nari; Kang, Seong-Jun; Lee, Sunho; Shin, Jun-Seop; Park, Chung-Gyu

    2018-03-04

    Pancreatic islet transplantation is an ultimate solution for treating patients with type 1 diabetes (T1D). The pig is an ideal donor of islets for replacing scarce human islets. Besides immunological hurdles, non-immunological hurdles including fragmentation and delayed engraftment of porcine islets need solutions to succeed in porcine islet xenotransplantation. In this study, we suggest a simple but effective modality, a cell/islet co-localizing composite, to overcome these challenges. Endothelial-like mesenchymal stem cells (EMSCs), differentiated from bone-marrow derived mouse mesenchymal stem cells (MSCs), and MSCs evenly coated the surface of porcine islets (>85%) through optimized culture conditions. Both MSCs and EMSCs significantly reduced the fragmentation of porcine islets and increased the islet masses, designated as islet equivalents (IEQs). In fibrin in vitro and in vivo angiogenesis analysis, constructed EMSC-islet composites showed higher angiogenic potentials than naked islets, MSC-islet composites, or human endothelial cell-islet composites. This novel delivery method of porcine islets may have beneficial effects on the engraftment of transplanted islets by prevention of fragmentation and enhancement of revascularization. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. The Spleen as an Optimal Site for Islet Transplantation and a Source of Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Naoaki Sakata

    2018-05-01

    Full Text Available This review demonstrates the unique potential of the spleen as an optimal site for islet transplantation and as a source of mesenchymal stem cells. Islet transplantation is a cellular replacement therapy used to treat severe diabetes mellitus; however, its clinical outcome is currently unsatisfactory. Selection of the most appropriate transplantation site is a major factor affecting the clinical success of this therapy. The spleen has long been studied as a candidate site for islet transplantation. Its advantages include physiological insulin drainage and regulation of immunity, and it has recently also been shown to contribute to the regeneration of transplanted islets. However, the efficacy of transplantation in the spleen is lower than that of intraportal transplantation, which is the current representative method of clinical islet transplantation. Safer and more effective methods of islet transplantation need to be established to allow the spleen to be used for clinical transplantation. The spleen is also of interest as a mesenchymal stem cell reservoir. Splenic mesenchymal stem cells contribute to the repair of damaged tissue, and their infusion may thus be a promising therapy for autoimmune diseases, including type 1 diabetes mellitus and Sjogren’s syndrome.

  18. The Spleen as an Optimal Site for Islet Transplantation and a Source of Mesenchymal Stem Cells.

    Science.gov (United States)

    Sakata, Naoaki; Yoshimatsu, Gumpei; Kodama, Shohta

    2018-05-07

    This review demonstrates the unique potential of the spleen as an optimal site for islet transplantation and as a source of mesenchymal stem cells. Islet transplantation is a cellular replacement therapy used to treat severe diabetes mellitus; however, its clinical outcome is currently unsatisfactory. Selection of the most appropriate transplantation site is a major factor affecting the clinical success of this therapy. The spleen has long been studied as a candidate site for islet transplantation. Its advantages include physiological insulin drainage and regulation of immunity, and it has recently also been shown to contribute to the regeneration of transplanted islets. However, the efficacy of transplantation in the spleen is lower than that of intraportal transplantation, which is the current representative method of clinical islet transplantation. Safer and more effective methods of islet transplantation need to be established to allow the spleen to be used for clinical transplantation. The spleen is also of interest as a mesenchymal stem cell reservoir. Splenic mesenchymal stem cells contribute to the repair of damaged tissue, and their infusion may thus be a promising therapy for autoimmune diseases, including type 1 diabetes mellitus and Sjogren’s syndrome.

  19. Islet transplantation in diabetic rats normalizes basal and exercise-induced energy metabolism

    NARCIS (Netherlands)

    Houwing, Harmina; Benthem, L.; Suylichem, P.T.R. van; Leest, J. van der; Strubbe, J.H.; Steffens, A.B.

    Transplantation of islets of Langerhans in diabetic rats normalizes resting glucose and insulin levels, but it remains unclear whether islet transplantation restores resting and exercise-induced energy metabolism. Therefore, we compared energy metabolism in islet transplanted rats with energy

  20. Diabetes Is Reversed in a Murine Model by Marginal Mass Syngeneic Islet Transplantation Using a Subcutaneous Cell Pouch Device.

    Science.gov (United States)

    Pepper, Andrew R; Pawlick, Rena; Gala-Lopez, Boris; MacGillivary, Amanda; Mazzuca, Delfina M; White, David J G; Toleikis, Philip M; Shapiro, A M James

    2015-11-01

    Islet transplantation is a successful β-cell replacement therapy for selected patients with type 1 diabetes mellitus. Although high rates of early insulin independence are achieved routinely, long-term function wanes over time. Intraportal transplantation is associated with procedural risks, requires multiple donors, and does not afford routine biopsy. Stem cell technologies may require potential for retrievability, and graft removal by hepatectomy is impractical. There is a clear clinical need for an alternative, optimized transplantation site. The subcutaneous space is a potential substitute, but transplantation of islets into this site has routinely failed to reverse diabetes. However, an implanted device, which becomes prevascularized before transplantation, may alter this equation. Syngeneic mouse islets were transplanted subcutaneously within Sernova Corp's Cell Pouch (CP). All recipients were preimplanted with CPs 4 weeks before diabetes induction and transplantation. After transplantation, recipients were monitored for glycemic control and glucose tolerance. Mouse islets transplanted into the CP routinely restored glycemic control with modest delay and responded well to glucose challenge, comparable to renal subcapsular islet grafts, despite a marginal islet dose, and normoglycemia was maintained until graft explantation. In contrast, islets transplanted subcutaneously alone failed to engraft. Islets within CPs stained positively for insulin, glucagon, and microvessels. The CP is biocompatible, forms an environment suitable for islet engraftment, and offers a potential alternative to the intraportal site for islet and future stem cell therapies.

  1. Islet Microencapsulation: Strategies and Clinical Status in Diabetes.

    Science.gov (United States)

    Omami, Mustafa; McGarrigle, James J; Reedy, Mick; Isa, Douglas; Ghani, Sofia; Marchese, Enza; Bochenek, Matthew A; Longi, Maha; Xing, Yuan; Joshi, Ira; Wang, Yong; Oberholzer, José

    2017-07-01

    Type 1 diabetes mellitus (T1DM) is an autoimmune disease that results from the destruction of insulin-producing pancreatic β cells in the islets of Langerhans. Islet cell transplantation has become a successful therapy for specific patients with T1DM with hypoglycemic unawareness. The reversal of T1DM by islet transplantation is now performed at many major medical facilities throughout the world. However, many challenges must still be overcome in order to achieve continuous, long-term successful transplant outcomes. Two major obstacles to this therapy are a lack of islet cells for transplantation and the need for life-long immunosuppressive treatment. Microencapsulation is seen as a technology that can overcome both these limitations of islet cell transplantation. This review depicts the present state of microencapsulated islet transplantation. Microencapsulation can play a significant role in overcoming the need for immunosuppression and lack of donor islet cells. This review focuses on microencapsulation and the clinical status of the technology in combating T1DM.

  2. Antigen-Encoding Bone Marrow Terminates Islet-Directed Memory CD8+ T-Cell Responses to Alleviate Islet Transplant Rejection

    DEFF Research Database (Denmark)

    Coleman, Miranda; Jessup, Claire F.; Bridge, Jennifer A.

    2016-01-01

    in islet transplantation, and this will extend to application of personalized approaches using stem cell–derived replacement β-cells. New approaches are required to limit memory autoimmune attack of transplanted islets or replacement β-cells. Here, we show that transfer of bone marrow encoding cognate......Islet-specific memory T cells arise early in type 1 diabetes (T1D), persist for long periods, perpetuate disease, and are rapidly reactivated by islet transplantation. As memory T cells are poorly controlled by “conventional” therapies, memory T cell–mediated attack is a substantial challenge......-cell responses, and this can alleviate destruction of antigen-expressing islets. This addresses a key challenge facing islet transplantation and, importantly, the clinical application of personalized β-cell replacement therapies using patient-derived stem cells....

  3. Transplantation of co-aggregates of Sertoli cells and islet cells into liver without immunosuppression.

    Science.gov (United States)

    Takemoto, Naohiro; Liu, Xibao; Takii, Kento; Teramura, Yuji; Iwata, Hiroo

    2014-02-15

    Transplantation of islets of Langerhans (islets) was used to treat insulin-dependent diabetes mellitus. However, islet grafts must be maintained by administration of immunosuppressive drugs, which can lead to complications in the long term. An approach that avoids immunosuppressive drug use is desirable. Co-aggregates of Sertoli cells and islet cells from BALB/c mice that were prepared by the hanging drop method were transplanted into C57BL/6 mouse liver through the portal vein as in human clinical islet transplantation. The core part of the aggregates contained mainly Sertoli cells, and these cells were surrounded by islet cells. The co-aggregates retained the functions of both Sertoli and islet cells. When 800 co-aggregates were transplanted into seven C57BL/6 mice via the portal vein, six of seven recipient mice demonstrated quasi-normoglycemia for more than 100 days. The hanging drop method is suitable for preparing aggregates of Sertoli and islet cells for transplantation. Notably, transplantation of these allogeneic co-aggregates into mice with chemically induced diabetes via the portal vein resulted in long-term graft survival without systemic immunosuppression.

  4. National Institutes of Health–Sponsored Clinical Islet Transplantation Consortium Phase 3 Trial: Manufacture of a Complex Cellular Product at Eight Processing Facilities

    Science.gov (United States)

    Balamurugan, A.N.; Szot, Gregory L.; Kin, Tatsuya; Liu, Chengyang; Czarniecki, Christine W.; Barbaro, Barbara; Bridges, Nancy D.; Cano, Jose; Clarke, William R.; Eggerman, Thomas L.; Hunsicker, Lawrence G.; Kaufman, Dixon B.; Khan, Aisha; Lafontant, David-Erick; Linetsky, Elina; Luo, Xunrong; Markmann, James F.; Naji, Ali; Korsgren, Olle; Oberholzer, Jose; Turgeon, Nicole A.; Brandhorst, Daniel; Chen, Xiaojuan; Friberg, Andrew S.; Lei, Ji; Wang, Ling-jia; Wilhelm, Joshua J.; Willits, Jamie; Zhang, Xiaomin; Hering, Bernhard J.; Posselt, Andrew M.; Stock, Peter G.; Shapiro, A.M. James

    2016-01-01

    Eight manufacturing facilities participating in the National Institutes of Health–sponsored Clinical Islet Transplantation (CIT) Consortium jointly developed and implemented a harmonized process for the manufacture of allogeneic purified human pancreatic islet (PHPI) product evaluated in a phase 3 trial in subjects with type 1 diabetes. Manufacturing was controlled by a common master production batch record, standard operating procedures that included acceptance criteria for deceased donor organ pancreata and critical raw materials, PHPI product specifications, certificate of analysis, and test methods. The process was compliant with Current Good Manufacturing Practices and Current Good Tissue Practices. This report describes the manufacturing process for 75 PHPI clinical lots and summarizes the results, including lot release. The results demonstrate the feasibility of implementing a harmonized process at multiple facilities for the manufacture of a complex cellular product. The quality systems and regulatory and operational strategies developed by the CIT Consortium yielded product lots that met the prespecified characteristics of safety, purity, potency, and identity and were successfully transplanted into 48 subjects. No adverse events attributable to the product and no cases of primary nonfunction were observed. PMID:27465220

  5. Nanoparticle delivery of donor antigens for transplant tolerance in allogeneic islet transplantation.

    Science.gov (United States)

    Bryant, Jane; Hlavaty, Kelan A; Zhang, Xiaomin; Yap, Woon-Teck; Zhang, Lei; Shea, Lonnie D; Luo, Xunrong

    2014-10-01

    Human islet cell transplantation is a promising treatment for type 1 diabetes; however, long-term donor-specific tolerance to islet allografts remains a clinically unmet goal. We have previously shown that recipient infusions of apoptotic donor splenocytes chemically treated with 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide (donor ECDI-SP) can mediate long-term acceptance of full major histocompatibility complex (MHC)-mismatched murine islet allografts without the use of immunosuppression. In this report, we investigated the use of poly(lactide-co-glycolide) (PLG) particles in lieu of donor ECDI-SP as a synthetic, cell-free carrier for delivery of donor antigens for the induction of transplant tolerance in full MHC-mismatched murine allogeneic islet transplantation. Infusions of donor antigen-coupled PLG particles (PLG-dAg) mediated tolerance in ∼20% of recipient mice, and the distribution of cellular uptake of PLG-dAg within the spleen was similar to that of donor ECDI-SP. PLG-dAg mediated the contraction of indirectly activated T cells but did not modulate the direct pathway of allorecognition. Combination of PLG-dAg with a short course of low dose immunosuppressant rapamycin at the time of transplant significantly improved the tolerance efficacy to ∼60%. Furthermore, altering the timing of PLG-dAg administration to a schedule that is more feasible for clinical transplantation resulted in equal tolerance efficacy. Thus, the combination therapy of PLG-dAg infusions with peritransplant rapamycin represents a clinically attractive, biomaterials-based and cell-free method for inducing long-term donor-specific tolerance for allogeneic cell transplantation, such as for allogeneic islet transplantation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Beneficial effect of D-allose for isolated islet culture prior to islet transplantation.

    Science.gov (United States)

    Kashiwagi, Hirotaka; Asano, Eisuke; Noguchi, Chisato; Sui, Li; Hossain, Akram; Akamoto, Shintaro; Okano, Keiichi; Tokuda, Masaaki; Suzuki, Yasuyuki

    2016-01-01

    Pretransplant restoration of islets damaged during isolation remains to be solved. In this study, we examined the effect of D-allose on islets isolated from rat pancreata prior to islet transplantation. Rat islets isolated from fresh pancreata were cultured overnight in Roswell Park Memorial Institute 1640 solution in the absence (group 1) or presence (group 2) of D-allose. Then we assessed stimulation index of insulin, and cure rate after islet transplantation to diabetic nude mice. We also measured malondialdehyde level and caspase 3 activity of islets after the overnight culture for assessment of the oxidative stress and the apoptosis. D-allose significantly improved insulin secretion of islets. The stimulation index in group 2 was significantly higher than in group 1. Cure rate after transplantation in group 2 was higher than in group 1 especially in the first week. The malondialdehyde level in group 2 was significantly lower than in group 1. But the caspase 3 activities in both groups did not differ. D-allose treatment of isolated islet culture prior to transplantation restored islet function and increased successful transplant rate. The results of this study suggested that D-allose improved function of damaged islets through its anti-oxidative activity. © 2015 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  7. Islet Oxygen Consumption Rate (OCR) Dose Predicts Insulin Independence in Clinical Islet Autotransplantation.

    Science.gov (United States)

    Papas, Klearchos K; Bellin, Melena D; Sutherland, David E R; Suszynski, Thomas M; Kitzmann, Jennifer P; Avgoustiniatos, Efstathios S; Gruessner, Angelika C; Mueller, Kathryn R; Beilman, Gregory J; Balamurugan, Appakalai N; Loganathan, Gopalakrishnan; Colton, Clark K; Koulmanda, Maria; Weir, Gordon C; Wilhelm, Josh J; Qian, Dajun; Niland, Joyce C; Hering, Bernhard J

    2015-01-01

    Reliable in vitro islet quality assessment assays that can be performed routinely, prospectively, and are able to predict clinical transplant outcomes are needed. In this paper we present data on the utility of an assay based on cellular oxygen consumption rate (OCR) in predicting clinical islet autotransplant (IAT) insulin independence (II). IAT is an attractive model for evaluating characterization assays regarding their utility in predicting II due to an absence of confounding factors such as immune rejection and immunosuppressant toxicity. Membrane integrity staining (FDA/PI), OCR normalized to DNA (OCR/DNA), islet equivalent (IE) and OCR (viable IE) normalized to recipient body weight (IE dose and OCR dose), and OCR/DNA normalized to islet size index (ISI) were used to characterize autoislet preparations (n = 35). Correlation between pre-IAT islet product characteristics and II was determined using receiver operating characteristic analysis. Preparations that resulted in II had significantly higher OCR dose and IE dose (p<0.001). These islet characterization methods were highly correlated with II at 6-12 months post-IAT (area-under-the-curve (AUC) = 0.94 for IE dose and 0.96 for OCR dose). FDA/PI (AUC = 0.49) and OCR/DNA (AUC = 0.58) did not correlate with II. OCR/DNA/ISI may have some utility in predicting outcome (AUC = 0.72). Commonly used assays to determine whether a clinical islet preparation is of high quality prior to transplantation are greatly lacking in sensitivity and specificity. While IE dose is highly predictive, it does not take into account islet cell quality. OCR dose, which takes into consideration both islet cell quality and quantity, may enable a more accurate and prospective evaluation of clinical islet preparations.

  8. Islet Oxygen Consumption Rate (OCR Dose Predicts Insulin Independence in Clinical Islet Autotransplantation.

    Directory of Open Access Journals (Sweden)

    Klearchos K Papas

    Full Text Available Reliable in vitro islet quality assessment assays that can be performed routinely, prospectively, and are able to predict clinical transplant outcomes are needed. In this paper we present data on the utility of an assay based on cellular oxygen consumption rate (OCR in predicting clinical islet autotransplant (IAT insulin independence (II. IAT is an attractive model for evaluating characterization assays regarding their utility in predicting II due to an absence of confounding factors such as immune rejection and immunosuppressant toxicity.Membrane integrity staining (FDA/PI, OCR normalized to DNA (OCR/DNA, islet equivalent (IE and OCR (viable IE normalized to recipient body weight (IE dose and OCR dose, and OCR/DNA normalized to islet size index (ISI were used to characterize autoislet preparations (n = 35. Correlation between pre-IAT islet product characteristics and II was determined using receiver operating characteristic analysis.Preparations that resulted in II had significantly higher OCR dose and IE dose (p<0.001. These islet characterization methods were highly correlated with II at 6-12 months post-IAT (area-under-the-curve (AUC = 0.94 for IE dose and 0.96 for OCR dose. FDA/PI (AUC = 0.49 and OCR/DNA (AUC = 0.58 did not correlate with II. OCR/DNA/ISI may have some utility in predicting outcome (AUC = 0.72.Commonly used assays to determine whether a clinical islet preparation is of high quality prior to transplantation are greatly lacking in sensitivity and specificity. While IE dose is highly predictive, it does not take into account islet cell quality. OCR dose, which takes into consideration both islet cell quality and quantity, may enable a more accurate and prospective evaluation of clinical islet preparations.

  9. Animal Models of Diabetes Mellitus for Islet Transplantation

    Directory of Open Access Journals (Sweden)

    Naoaki Sakata

    2012-01-01

    Full Text Available Due to current improvements in techniques for islet isolation and transplantation and protocols for immunosuppressants, islet transplantation has become an effective treatment for severe diabetes patients. Many diabetic animal models have contributed to such improvements. In this paper, we focus on 3 types of models with different mechanisms for inducing diabetes mellitus (DM: models induced by drugs including streptozotocin (STZ, pancreatomized models, and spontaneous models due to autoimmunity. STZ-induced diabetes is one of the most commonly used experimental diabetic models and is employed using many specimens including rodents, pigs or monkeys. The management of STZ models is well established for islet studies. Pancreatomized models reveal different aspects compared to STZ-induced models in terms of loss of function in the increase and decrease of blood glucose and therefore are useful for evaluating the condition in total pancreatomized patients. Spontaneous models are useful for preclinical studies including the assessment of immunosuppressants because such models involve the same mechanisms as type 1 DM in the clinical setting. In conclusion, islet researchers should select suitable diabetic animal models according to the aim of the study.

  10. Beta-Cell Replacement: Pancreas and Islet Cell Transplantation.

    Science.gov (United States)

    Niclauss, Nadja; Meier, Raphael; Bédat, Benoît; Berishvili, Ekaterine; Berney, Thierry

    2016-01-01

    Pancreas and islet transplantation are 2 types of beta-cell replacement therapies for type 1 diabetes mellitus. Since 1966, when pancreas transplantation was first performed, it has evolved to become a highly efficient procedure with high success rates, thanks to advances in surgical technique and immunosuppression. Pancreas transplantation is mostly performed as simultaneous pancreas-kidney transplantation in patients with end-stage nephropathy secondary to diabetes. In spite of its efficiency, pancreas transplantation is still a major surgical procedure burdened by high morbidity, which called for the development of less invasive and hazardous ways of replacing beta-cell function in the past. Islet transplantation was developed in the 1970s as a minimally invasive procedure with initially poor outcomes. However, since the report of the 'Edmonton protocol' in 2000, the functional results of islet transplantation have substantially and constantly improved and are about to match those of whole pancreas transplantation. Islet transplantation is primarily performed alone in nonuremic patients with severe hypoglycemia. Both pancreas transplantation and islet transplantation are able to abolish hypoglycemia and to prevent or slow down the development of secondary complications of diabetes. Pancreas transplantation and islet transplantation should be seen as two complementary, rather than competing, therapeutic approaches for beta-cell replacement that are able to optimize organ donor use and patient care. © 2016 S. Karger AG, Basel.

  11. Sequential kidney/islet transplantation using prednisone-free immunosuppression.

    Science.gov (United States)

    Kaufman, Dixon B; Baker, Marshall S; Chen, Xiaojuan; Leventhal, Joseph R; Stuart, Frank P

    2002-08-01

    Islet transplantation is becoming established as a treatment option for type I diabetes in select patients. Individuals with type I diabetes who have previously received a successful kidney allograft may be good candidates for islet transplantation. They have already assumed the risks of chronic immunosuppression, so the added procedural risk of a subsequent islet transplant would be minimal. Furthermore, because of the preimmunosuppressed state it is possible that islet-after-kidney transplantation may result in a more efficient early islet engraftment. Consequently, insulin independence might be achieved with significantly fewer islets than the approximately 8-10,000 islet equivalents/kg/b.w. currently required. A mass that usually demands two or more cadaveric donors. A case of successful islet-after-kidney transplantation is described using the steroid-free Edmonton immunosuppression protocol. Characteristics of the final islet product are: a) islet equivalents: 265,888 (4100 islet equivalents/kg/b.w.); b) islet purity: 75-80%; c) viability: >95% (trypan blue exclusion); and d) mean islet potency (static low-high glucose challenge): 4.16 +/- 1.91-fold increase. Post-transplant the patient's hypoglycemic episodes abated. Exogenous insulin requirements were eliminated at week 12 post-transplant as basal and Ensure (Abbott Laboratories, Abbott Park, IL, USA) oral glucose stimulated C-peptide levels peaked and stabilized. Twenty-four-hour continuous glucose monitoring confirmed moment-to-moment glycemic control, and periodic nonfasting finger stick glucose determinations over the next month confirmed glycemia was controlled. Hemoglobin A1c levels declined from a pretransplant level of 6.9% to 5.3%. Renal allograft function remained changed.

  12. Microwell Scaffolds for the Extrahepatic Transplantation of Islets of Langerhans

    Science.gov (United States)

    Buitinga, Mijke; Truckenmüller, Roman; Engelse, Marten A.; Moroni, Lorenzo; Ten Hoopen, Hetty W. M.; van Blitterswijk, Clemens A.; de Koning, Eelco JP.; van Apeldoorn, Aart A.; Karperien, Marcel

    2013-01-01

    Allogeneic islet transplantation into the liver has the potential to restore normoglycemia in patients with type 1 diabetes. However, the suboptimal microenvironment for islets in the liver is likely to be involved in the progressive islet dysfunction that is often observed post-transplantation. This study validates a novel microwell scaffold platform to be used for the extrahepatic transplantation of islet of Langerhans. Scaffolds were fabricated from either a thin polymer film or an electrospun mesh of poly(ethylene oxide terephthalate)-poly(butylene terephthalate) (PEOT/PBT) block copolymer (composition: 4000PEOT30PBT70) and were imprinted with microwells, ∼400 µm in diameter and ∼350 µm in depth. The water contact angle and water uptake were 39±2° and 52.1±4.0 wt%, respectively. The glucose flux through electrospun scaffolds was three times higher than for thin film scaffolds, indicating enhanced nutrient diffusion. Human islets cultured in microwell scaffolds for seven days showed insulin release and insulin content comparable to those of free-floating control islets. Islet morphology and insulin and glucagon expression were maintained during culture in the microwell scaffolds. Our results indicate that the microwell scaffold platform prevents islet aggregation by confinement of individual islets in separate microwells, preserves the islet’s native rounded morphology, and provides a protective environment without impairing islet functionality, making it a promising platform for use in extrahepatic islet transplantation. PMID:23737999

  13. Transplanted human pancreatic islets after long-term insulin independence

    DEFF Research Database (Denmark)

    Muller, Y D; Gupta, Shashank; Morel, P

    2013-01-01

    Long-term insulin independence after islets of Langerhans transplantation is rarely achieved. The aims of this study were to identify the histological and immunological features of islets transplanted in a type 1 diabetic patient who died of a cerebral hemorrhage after >13 years insulin independe...

  14. Small Islets Transplantation Superiority to Large Ones: Implications from Islet Microcirculation and Revascularization

    Directory of Open Access Journals (Sweden)

    Wenjuan Li

    2014-01-01

    Full Text Available Pancreatic islet transplantation is a promising therapy to regain glycemic control in diabetic patients. The selection of ideal grafts is the basis to guarantee short-term effectivity and longevity of the transplanted islets. Contradictory to the traditional notion, recent findings implied the superiority of small islets for better transplantation outcomes rather than the large and intact ones. However, the mechanisms remain to be elucidated. Recent evidences emphasized the major impact of microcirculation on islet β-cell mass and function. And potentials in islet graft revascularization are crucial for their survival and preserved function in the recipient. In this study, we verified the distinct histological phenotype and functionality of small islets versus large ones both in vitro and in vivo. With efforts to exploring the differences in microcirculation and revascularization of islet grafts, we further evaluated local expressions of angiotensin and vascular endothelial growth factor A (VEGF-A at different levels. Our findings reveal that, apart from the higher density of insulin-producing β-cells, small islets express less angiotensin and more angiotrophic VEGF-A. We therefore hypothesized a logical explanation of the small islet superiority for transplantation outcome from the aspects of facilitated microcirculation and revascularization intrinsically in small islets.

  15. Islet transplantation in multicenter networks: the GRAGIL example

    International Nuclear Information System (INIS)

    Thierry Berney; Pierre-Yves Benhamou; Laurence Kessler; Philippe Morel

    2006-01-01

    Purpose of review: The enthusiasm generated by the results of the Edmonton protocol of islet transplantation is inciting a great number of institutions to start such programs. However, the procedure of islet isolation and purification is costly, complex and technically challenging. In order to share costs and to avoid facing the steep learning curve of the procedure, many centers interested in islet transplantation have looked into collaborating with experienced groups serving as core islet isolation facilities. Recent findings: The proof of principle that remote islet processing and shipment could be successfully implemented with obtainng the Portland/Minneapolis, Huddinge/Giessen and Houston/Miami partnerships. Moreover, in order to increase both the donor pool and the number of patients gaining access to islet transplantation, multicenter networks, such as the Swiss-French GRAGIL consortium and the 4-country Nordic Network in Scandinavia have been built. The GRAGIL group has been fully operational since 1999, allowing the transplantation of 27 islet preparations processed in Geneva, Switzerland into 20 recipients in France over the course of 4.5 years. Organizational issues in the design of such networks are discussed based on the example of the GRAGIL experience. Summary: The feasibility and the efficiency of islet transplantation in multicenter networks have been demonstrated. This strategy allows to increase the donor pool and the accessibility to islet transplantation in an extended population area. (authors)

  16. Fibroblasts accelerate islet revascularization and improve long-term graft survival in a mouse model of subcutaneous islet transplantation.

    Directory of Open Access Journals (Sweden)

    Marcos Perez-Basterrechea

    Full Text Available Pancreatic islet transplantation has been considered for many years a promising therapy for beta-cell replacement in patients with type-1 diabetes despite that long-term clinical results are not as satisfactory. This fact points to the necessity of designing strategies to improve and accelerate islets engraftment, paying special attention to events assuring their revascularization. Fibroblasts constitute a cell population that collaborates on tissue homeostasis, keeping the equilibrium between production and degradation of structural components as well as maintaining the required amount of survival factors. Our group has developed a model for subcutaneous islet transplantation using a plasma-based scaffold containing fibroblasts as accessory cells that allowed achieving glycemic control in diabetic mice. Transplanted tissue engraftment is critical during the first days after transplantation, thus we have gone in depth into the graft-supporting role of fibroblasts during the first ten days after islet transplantation. All mice transplanted with islets embedded in the plasma-based scaffold reversed hyperglycemia, although long-term glycemic control was maintained only in the group transplanted with the fibroblasts-containing scaffold. By gene expression analysis and histology examination during the first days we could conclude that these differences might be explained by overexpression of genes involved in vessel development as well as in β-cell regeneration that were detected when fibroblasts were present in the graft. Furthermore, fibroblasts presence correlated with a faster graft re-vascularization, a higher insulin-positive area and a lower cell death. Therefore, this work underlines the importance of fibroblasts as accessory cells in islet transplantation, and suggests its possible use in other graft-supporting strategies.

  17. Fibroblasts accelerate islet revascularization and improve long-term graft survival in a mouse model of subcutaneous islet transplantation.

    Science.gov (United States)

    Perez-Basterrechea, Marcos; Esteban, Manuel Martinez; Alvarez-Viejo, Maria; Fontanil, Tania; Cal, Santiago; Sanchez Pitiot, Marta; Otero, Jesus; Obaya, Alvaro Jesus

    2017-01-01

    Pancreatic islet transplantation has been considered for many years a promising therapy for beta-cell replacement in patients with type-1 diabetes despite that long-term clinical results are not as satisfactory. This fact points to the necessity of designing strategies to improve and accelerate islets engraftment, paying special attention to events assuring their revascularization. Fibroblasts constitute a cell population that collaborates on tissue homeostasis, keeping the equilibrium between production and degradation of structural components as well as maintaining the required amount of survival factors. Our group has developed a model for subcutaneous islet transplantation using a plasma-based scaffold containing fibroblasts as accessory cells that allowed achieving glycemic control in diabetic mice. Transplanted tissue engraftment is critical during the first days after transplantation, thus we have gone in depth into the graft-supporting role of fibroblasts during the first ten days after islet transplantation. All mice transplanted with islets embedded in the plasma-based scaffold reversed hyperglycemia, although long-term glycemic control was maintained only in the group transplanted with the fibroblasts-containing scaffold. By gene expression analysis and histology examination during the first days we could conclude that these differences might be explained by overexpression of genes involved in vessel development as well as in β-cell regeneration that were detected when fibroblasts were present in the graft. Furthermore, fibroblasts presence correlated with a faster graft re-vascularization, a higher insulin-positive area and a lower cell death. Therefore, this work underlines the importance of fibroblasts as accessory cells in islet transplantation, and suggests its possible use in other graft-supporting strategies.

  18. Facilitated Engraftment of Isolated Islets Coated With Expanded Vascular Endothelial Cells for Islet Transplantation.

    Science.gov (United States)

    Barba-Gutierrez, D Alonso; Daneri-Navarro, A; Villagomez-Mendez, J Jesus Alejandro; Kanamune, J; Robles-Murillo, A Karina; Sanchez-Enriquez, S; Villafan-Bernal, J Rafael; Rivas-Carrillo, J D

    2016-03-01

    Diabetes is complex disease, which involves primary metabolic changes followed by immunological and vascular pathophysiological adjustments. However, it is mostly characterized by an unbalanced decreased number of the β-cells unable to maintain the metabolic requirements and failure to further regenerate newly functional pancreatic islets. The objective of this study was to analyze the properties of the endothelial cells to facilitate the islet cells engraftment after islet transplantation. We devised a co-cultured engineer system to coat isolated islets with vascular endothelial cells. To assess the cell integration of cell-engineered islets, we stained them for endothelial marker CD31 and nuclei counterstained with DAPI dye. We comparatively performed islet transplantations into streptozotocin-induced diabetic mice and recovered the islet grafts for morphometric analyses on days 3, 7, 10, and 30. Blood glucose levels were measured continuously after islet transplantation to monitor the functional engraftment and capacity to achieve metabolic control. Cell-engineered islets showed a well-defined rounded shape after co-culture when compared with native isolated islets. Furthermore, the number of CD31-positive cells layered on the islet surface showed a direct proportion with engraftment capacities and less TUNEL-positive cells on days 3 and 7 after transplantation. We observed that vascular endothelial cells could be functional integrated into isolated islets. We also found that islets that are coated with vascular endothelial cells increased their capacity to engraft. These findings indicate that islets coated with endothelial cells have a greater capacity of engraftment and thus establish a definitely vascular network to support the metabolic requirements. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Molecular Imaging: A Promising Tool to Monitor Islet Transplantation

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2011-01-01

    Full Text Available Replacement of insulin production by pancreatic islet transplantation has great potential as a therapy for type 1 diabetes mellitus. At present, the lack of an effective approach to islet grafts assessment limits the success of this treatment. The development of molecular imaging techniques has the potential to fulfill the goal of real-time noninvasive monitoring of the functional status and viability of the islet grafts. We review the application of a variety of imaging modalities for detecting endogenous and transplanted beta-cell mass. The review also explores the various molecular imaging strategies for assessing islet delivery, the metabolic effects on the islet grafts as well as detection of immunorejection. Here, we highlight the use of combined imaging and therapeutic interventions in islet transplantation and the in vivo monitoring of stem cells differentiation into insulin-producing cells.

  20. Salvage Islet Auto Transplantation After Relaparatomy.

    Science.gov (United States)

    Balzano, Gianpaolo; Nano, Rita; Maffi, Paola; Mercalli, Alessia; Melzi, Raffaelli; Aleotti, Francesca; Gavazzi, Francesca; Berra, Cesare; De Cobelli, Francesco; Venturini, Massimo; Magistretti, Paola; Scavini, Marina; Capretti, Giovanni; Del Maschio, Alessandro; Secchi, Antonio; Zerbi, Alessandro; Falconi, Massimo; Piemonti, Lorenzo

    2017-10-01

    To assess feasibility, safety, and metabolic outcome of islet auto transplantation (IAT) in patients undergoing completion pancreatectomy because of sepsis or bleeding after pancreatic surgery. From November 2008 to October 2016, approximately 22 patients were candidates to salvage IAT during emergency relaparotomy because of postpancreatectomy sepsis (n = 11) or bleeding (n = 11). Feasibility, efficacy, and safety of salvage IAT were compared with those documented in a cohort of 36 patients who were candidate to simultaneous IAT during nonemergency preemptive completion pancreatectomy through the pancreaticoduodenectomy. The percentage of candidates that received the infusion of islets was significantly lower in salvage IAT than simultaneous IAT (59.1% vs 88.9%, P = 0.008), mainly because of a higher rate of inadequate islet preparations. Even if microbial contamination of islet preparation was significantly higher in candidates to salvage IAT than in those to simultaneous IAT (78.9% vs 20%, P < 0.001), there was no evidence of a higher rate of complications related to the procedure. Median follow-up was 5.45 ± 0.52 years. Four (36%) of 11 patients reached insulin independence, 6 patients (56%) had partial graft function, and 1 patient (9%) had primary graft nonfunction. At the last follow-up visit, median fasting C-peptide was 0.43 (0.19-0.93) ng/mL; median insulin requirement was 0.38 (0.04-0.5) U/kg per day, and median HbA1c was 6.6% (5.9%-8.1%). Overall mortality, in-hospital mortality, metabolic outcome, graft survival, and insulin-free survival after salvage IAT were not different from those documented after simultaneous IAT. Our data demonstrate the feasibility, efficacy, and safety of salvage IAT after relaparotomy.

  1. Has the gap between pancreas and islet transplantation closed?

    Science.gov (United States)

    Niclauss, Nadja; Morel, Philippe; Berney, Thierry

    2014-09-27

    Both pancreas and islet transplantations are therapeutic options for complicated type 1 diabetes. Until recent years, outcomes of islet transplantation have been significantly inferior to those of whole pancreas. Islet transplantation is primarily performed alone in patients with severe hypoglycemia, and recent registry reports have suggested that results of islet transplantation alone in this indication may be about to match those of pancreas transplant alone in insulin independence. Figures of 50% insulin independence at 5 years for either procedure have been cited. In this article, we address the question whether islet transplantation has indeed bridged the gap with whole pancreas. Looking at the evidence to answer this question, we propose that although pancreas may still be more efficient in taking recipients off insulin than islets, there are in fact numerous "gaps" separating both procedures that must be taken into the equation. These "gaps" relate to organ utilization, organ allocation, indication for transplantation, and morbidity. In-depth analysis reveals that islet transplantation, in fact, has an edge on whole pancreas in some of these aspects. Accordingly, attempts should be made to bridge these gaps from both sides to achieve the same level of success with either procedure. More realistically, it is likely that some of these gaps will remain and that both procedures will coexist and complement each other, to ensure that β cell replacement can be successfully implemented in the greatest possible number of patients with type 1 diabetes.

  2. Islet cell transplantation for the treatment of type 1 diabetes: recent advances and future challenges

    Science.gov (United States)

    Bruni, Anthony; Gala-Lopez, Boris; Pepper, Andrew R; Abualhassan, Nasser S; Shapiro, AM James

    2014-01-01

    Islet transplantation is a well-established therapeutic treatment for a subset of patients with complicated type I diabetes mellitus. Prior to the Edmonton Protocol, only 9% of the 267 islet transplant recipients since 1999 were insulin independent for >1 year. In 2000, the Edmonton group reported the achievement of insulin independence in seven consecutive patients, which in a collaborative team effort propagated expansion of clinical islet transplantation centers worldwide in an effort to ameliorate the consequences of this disease. To date, clinical islet transplantation has established improved success with insulin independence rates up to 5 years post-transplant with minimal complications. In spite of marked clinical success, donor availability and selection, engraftment, and side effects of immunosuppression remain as existing obstacles to be addressed to further improve this therapy. Clinical trials to improve engraftment, the availability of insulin-producing cell sources, as well as alternative transplant sites are currently under investigation to expand treatment. With ongoing experimental and clinical studies, islet transplantation continues to be an exciting and attractive therapy to treat type I diabetes mellitus with the prospect of shifting from a treatment for some to a cure for all. PMID:25018643

  3. Application of Rotating Wall Vessel (RWV) Cell Culture for Pancreas Islet Cell Transplantation

    Science.gov (United States)

    Rutzky, Lynne P.

    1998-01-01

    Type I insulin-dependent diabetes mellitus (IDDM) remains a major cause of morbidity and mortality in both pediatric and adult populations, despite significant advances in medical management. While insulin therapy treats symptoms of acute diabetes, it fails to prevent chronic complications such as microvascular disease, blindness, neuropathy, and chronic renal failure. Strict control of blood glucose concentrations delays but does not prevent the onset and progression of secondary complications. Although, whole pancreas transplantation restores physiological blood glucose levels, a continuous process of allograft rejection causes vascular and exocrine-related complications. Recent advances in methods for isolation and purification of pancreatic islets make transplantation of islet allografts an attractive alternative to whole pancreas transplantation. However, immunosuppressive drugs are necessary to prevent rejection of islet allografts and many of these drugs are known to be toxic to the islets. Since auto-transplants of isolated islets following total pancreatectomy survive and function in vivo, it is apparent that a major obstacle to successful clinical islet transplantation is the immunogenicity of the islet allografts.

  4. Identification of transplanted pancreatic islet cells by radioactive Dithizone-[131I]-Histamine conjugate. Preliminary report

    International Nuclear Information System (INIS)

    Garnuszek, P.; Licinska, I.; Mazurek, A.P.; Mrozek, A.; Wardawa, A.; Fiedor, P.S.

    2000-01-01

    Background: The unique mechanism of dithizone action in the interior of the viable pancreatic islet suggests the possible development of a specific radiopharmaceutical that may have a potential clinical application in the diagnosis of the pancreatic organ allografts or islets rejection. The radiodiagnostic properties of the newly developed radioactive analogue of dithizone, i.e. Dithizone-[131I]-Histamine conjugate have been evaluated in the present study. METHODS: The four islet cells transplantation models were chosen for this purpose. The most important feature of the Dithizone-[131I]-Histamine conjugate is its possessed ability of zinc chelation. As was presented in the recent study, the conjugate stains pink-reddish the isolated pancreatic islets in vitro. Among the studied transplantation models, only the islets grafting under testis capsule enabled determination of the pancreatic islets in rats by radioactive Dithizone-[131I]-Histamine conjugate. The level of the radioactivity in the recipient testis (right) was almost two times higher compared to the controls (0.24 v. 0.13% ID/g, respectively). CONCLUSIONS: These preliminary data demonstrate the ability of the developed radioactive analogue of dithizone for in vivo identification of transplanted pancreatic islets, and suggests a potential clinical application of the radiodithizone in the diagnosis of the pancreatic islet rejection. (author)

  5. Islet Transplantation in Type 1 Diabetes: Ongoing Challenges, Refined Procedures, and Long-Term Outcome

    Science.gov (United States)

    Shapiro, A.M. James

    2012-01-01

    Remarkable progress has been made in islet transplantation over a span of 40 years. Once just an experimental curiosity in mice, this therapy has moved forward, and can now provide robust therapy for highly selected patients with type 1 diabetes (T1D), refractory to stabilization by other means. This progress could not have occurred without extensive dynamic international collaboration. Currently, 1,085 patients have undergone islet transplantation at 40 international sites since the Edmonton Protocol was reported in 2000 (752 allografts, 333 autografts), according to the Collaborative Islet Transplant Registry. The long-term results of islet transplantation in selected centers now match registry data of pancreas-alone transplantation, with 6 sites reporting five-year insulin independence rates ≥50%. Islet transplantation has been criticized for the use of multiple donor pancreas organs, but progress has also occurred in single-donor success, with 10 sites reporting increased single-donor engraftment. The next wave of innovative clinical trial interventions will address instant blood-mediated inflammatory reaction (IBMIR), apoptosis, and inflammation, and will translate into further marked improvements in single-donor success. Effective control of auto- and alloimmunity is the key to long-term islet function, and high-resolution cellular and antibody-based assays will add considerable precision to this process. Advances in immunosuppression, with new antibody-based targeting of costimulatory blockade and other T-B cellular signaling, will have further profound impact on the safety record of immunotherapy. Clinical trials will move forward shortly to test out new human stem cell derived islets, and in parallel trials will move forward, testing pig islets for compatibility in patients. Induction of immunological tolerance to self-islet antigens and to allografts is a difficult challenge, but potentially within our grasp. PMID:23804275

  6. Anti-Inflammatory Strategies in Intrahepatic Islet Transplantation: A Comparative Study in Preclinical Models.

    Science.gov (United States)

    Citro, Antonio; Cantarelli, Elisa; Pellegrini, Silvia; Dugnani, Erica; Piemonti, Lorenzo

    2018-02-01

    The identification of pathway(s) playing a pivotal role in peritransplant detrimental inflammatory events represents the crucial step toward a better management and outcome of pancreatic islet transplanted patients. Recently, we selected the CXCR1/2 inhibition as a relevant strategy in enhancing pancreatic islet survival after transplantation. Here, the most clinically used anti-inflammatory compounds (IL1-receptor antagonist, steroids, and TNF-α inhibitor) alone or in combination with a CXCR1/2 inhibitor were evaluated in their ability to improve engraftment or delay graft rejection. To rule out bias related to transplantation site, we used well-established preclinical syngeneic (250 C57BL/6 equivalent islets in C57BL/6) and allogeneic (400 Balb/c equivalent islets in C57BL6) intrahepatic islet transplantation platforms. In mice, we confirmed that targeting the CXCR1/2 pathway is crucial in preserving islet function and improving engraftment. In the allogeneic setting, CXCR1/2 inhibitor alone could reduce the overall recruitment of transplant-induced leukocytes and significantly prolong the time to graft rejection both as a single agent and in combination with immunosuppression. No other anti-inflammatory compounds tested (IL1-receptor antagonist, steroids, and TNF-α inhibitor) alone or in combination with CXCR1/2 inhibitor improve islet engraftment and significantly delay graft rejection in the presence of MMF + FK-506 immunosuppressive treatment. These findings indicate that only the CXCR1/2-mediated axis plays a crucial role in controlling the islet damage and should be a target for intervention to improve the efficiency of islet transplantation.

  7. Autologous islet transplantation with remote islet isolation after pancreas resection for chronic pancreatitis.

    Science.gov (United States)

    Tai, Denise S; Shen, Na; Szot, Gregory L; Posselt, Andrew; Feduska, Nicholas J; Habashy, Andrew; Clerkin, Barbara; Core, Erin; Busuttil, Ronald W; Hines, O Joe; Reber, Howard A; Lipshutz, Gerald S

    2015-02-01

    Autologous islet transplantation is an elegant and effective method for preserving euglycemia in patients undergoing near-total or total pancreatectomy for severe chronic pancreatitis. However, few centers worldwide perform this complex procedure, which requires interdisciplinary coordination and access to a sophisticated Food and Drug Administration-licensed islet-isolating facility. To investigate outcomes from a single institutional case series of near-total or total pancreatectomy and autologous islet transplantation using remote islet isolation. Retrospective cohort study between March 1, 2007, and December 31, 2013, at tertiary academic referral centers among 9 patients (age range, 13-47 years) with chronic pancreatitis and reduced quality of life after failed medical management. Pancreas resection, followed by transport to a remote facility for islet isolation using a modified Ricordi technique, with immediate transplantation via portal vein infusion. Islet yield, pain assessment, insulin requirement, costs, and transport time. Eight of nine patients had successful islet isolation after near-total or total pancreatectomy. Four of six patients with total pancreatectomy had islet yields exceeding 5000 islet equivalents per kilogram of body weight. At 2 months after surgery, all 9 patients had significantly reduced pain or were pain free. Of these patients, 2 did not require insulin, and 1 required low doses. The mean transport cost was $16,527, and the mean transport time was 3½ hours. Pancreatic resection with autologous islet transplantation for severe chronic pancreatitis is a safe and effective final alternative to ameliorate debilitating pain and to help prevent the development of surgical diabetes. Because many centers lack access to an islet-isolating facility, we describe our experience using a regional 2-center collaboration as a successful model to remotely isolate cells, with outcomes similar to those of larger case series.

  8. Islet Cell Transplantation: MedlinePlus Health Topic

    Science.gov (United States)

    ... and Kidney Diseases) Learn More Beta Cell Breakthroughs (American Diabetes Association) Innovative Approaches to Treating Type 1 Diabetes Addressed in Beta-Cell Replacement Presentations (American Diabetes Association) Islet Transplantation (American Diabetes Association) Also in Spanish ...

  9. A bilaminated decellularized scaffold for islet transplantation: Structure, properties and functions in diabetic mice.

    Science.gov (United States)

    Wang, Xi; Wang, Kai; Zhang, Wei; Qiang, Ming; Luo, Ying

    2017-09-01

    Ectopic transplantation of islets provides a beta cell-replacement approach that may allow the recovery of physiological regulation of the blood sugar level in patients with Type I diabetes (T1D). In development of new extrahepatic islet transplantation protocols in support of the islet engraftment, it is pivotal to develop scaffold materials with multifaceted functions to provide beneficial microenvironment, mediate host response in favor of vascularization/islet integration and maintain long-term islet function at the transplantation site. In this study, a new composite bilaminar decellularized scaffold (CDS) was fabricated with differential structural, degradation and mechanical properties by the combination of a fast-degrading porous collagen matrix and a mechanically supportive porcine pericardium. When investigated in the epididymal fat pad in syngeneic mouse models, it was shown that CDS could serve as superior scaffolds to promote islet adhesion and viability, and islet-CDS constructs also allowed rapid reversal of the hyperglycemic condition in the host. The engraftment and effects of islets were achieved at low islet numbers, accompanied by minimal adverse tissue reactions and optimal islet integration with the surrounding fat tissue. The bioactive surface, mechanical/chemical durability and biocompatibility of the CDS may all have played important roles in facilitating the engraftment of islets. Our study provided new insights into scaffold's function in the interplay of cells, materials and host tissue and the extracellular matrix-based scaffolds have potential for clinical translation in the beta cell-replacement therapy to treat T1D. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Single-donor islet transplantation and long-term insulin independence in select patients with type 1 diabetes mellitus.

    Science.gov (United States)

    Al-Adra, David P; Gill, Richdeep S; Imes, Sharleen; O'Gorman, Doug; Kin, Tatsuya; Axford, Sara J; Shi, Xinzhe; Senior, Peter A; Shapiro, A M James

    2014-11-15

    Islet transplantation is a recognized treatment option for select patients with type I diabetes mellitus. However, islet infusions from multiple donors are often required to achieve insulin independence. Ideally, insulin independence would be achieved routinely with only a single donor. Identification of factors associated with insulin independence after single-donor islet transplantation may help to select recipient-donor combinations with the highest probability of success. Subjects undergoing islet transplantation at a single center (Edmonton, Canada) between March 1999 and August 2013 were included. Recipient, donor, and transplant characteristics were collected and compared between recipients who became insulin independent after one islet transplantation and those who did not. Thirty-one patients achieved insulin independence after a single-donor islet transplantation, and 149 did not. Long-term insulin-free survival was not different between the groups. Factors significantly associated with single-donor success included recipient age, insulin requirement at baseline, donor weight, donor body mass index, islet transplant mass, and peritransplant heparin and insulin administration. On multivariate analysis, pretransplantation daily insulin requirements, the use of peritransplantation heparin and insulin infusions, and islet transplant mass remained significant. We have identified clinically relevant differences defining the achievement of insulin independence after single-donor transplantation. Based on these differences, a preoperative insulin requirement of less than 0.6 U/kg per day and receiving more than 5,646 islet equivalents (IEQ)/kg have a sensitivity of 84% and 71% and specificity of 50% and 50%, respectively, for insulin independence after single-donor islet transplantation. With ideal patient selection, this finding could potentially increase single-donor transplantation success and may be especially relevant for presensitized subjects or those who

  11. Autologous Pancreatic Islet Transplantation in Human Bone Marrow

    Science.gov (United States)

    Maffi, Paola; Balzano, Gianpaolo; Ponzoni, Maurilio; Nano, Rita; Sordi, Valeria; Melzi, Raffaella; Mercalli, Alessia; Scavini, Marina; Esposito, Antonio; Peccatori, Jacopo; Cantarelli, Elisa; Messina, Carlo; Bernardi, Massimo; Del Maschio, Alessandro; Staudacher, Carlo; Doglioni, Claudio; Ciceri, Fabio; Secchi, Antonio; Piemonti, Lorenzo

    2013-01-01

    The liver is the current site of choice for pancreatic islet transplantation, even though it is far from being ideal. We recently have shown in mice that the bone marrow (BM) may be a valid alternative to the liver, and here we report a pilot study to test feasibility and safety of BM as a site for islet transplantation in humans. Four patients who developed diabetes after total pancreatectomy were candidates for the autologous transplantation of pancreatic islet. Because the patients had contraindications for intraportal infusion, islets were infused in the BM. In all recipients, islets engrafted successfully as shown by measurable posttransplantation C-peptide levels and histopathological evidence of insulin-producing cells or molecular markers of endocrine tissue in BM biopsy samples analyzed during follow-up. Thus far, we have recorded no adverse events related to the infusion procedure or the presence of islets in the BM. Islet function was sustained for the maximum follow-up of 944 days. The encouraging results of this pilot study provide new perspectives in identifying alternative sites for islet infusion in patients with type 1 diabetes. Moreover, this is the first unequivocal example of successful engraftment of endocrine tissue in the BM in humans. PMID:23733196

  12. Immunogenicity of Anti-HLA Antibodies in Pancreas and Islet Transplantation.

    Science.gov (United States)

    Chaigne, Benjamin; Geneugelijk, Kirsten; Bédat, Benoît; Ahmed, Mohamed Alibashe; Hönger, Gideon; De Seigneux, Sophie; Demuylder-Mischler, Sandrine; Berney, Thierry; Spierings, Eric; Ferrari-Lacraz, Sylvie; Villard, Jean

    2016-11-01

    The aim of the current study was to characterize the anti-HLA antibodies before and after pancreatic islet or pancreas transplantation. We assessed the risk of anti-donor-specific antibody (DSA) sensitization in a single-center, retrospective clinical study at Geneva University Hospital. Data regarding clinical characteristics, graft outcome, HLA mismatch, donor HLA immunogenicity, and anti-HLA antibody characteristics were collected. Between January 2008 and July 2014, 18 patients received islet transplants, and 26 patients received a pancreas transplant. Eleven out of 18 patients (61.1%) in the islet group and 12 out of 26 patients (46.2%) in the pancreas group had anti-HLA antibodies. Six patients (33.3%) developed DSAs against HLA of the islets, and 10 patients (38.4%) developed DSAs against HLA of the pancreas. Most of the DSAs were at a low level. Several parameters such as gender, number of times cells were transplanted, HLA mismatch, eplet mismatch and PIRCHE-II numbers, rejection, and infection were analyzed. Only the number of PIRCHE-II was associated with the development of anti-HLA class II de novo DSAs. Overall, the development of de novo DSAs did not influence graft survival as estimated by insulin independence. Our results indicated that pretransplant DSAs at low levels do not restrict islet or pancreas transplantation [especially islet transplantation (27.8% vs. 15.4.%)]. De novo DSAs do occur at a similar rate in both pancreas and islet transplant recipients (mainly of class II), and the immunogenicity of donor HLA is a parameter that should be taken into consideration. When combined with an immunosuppressive regimen and close follow-up, development of low levels of DSAs was not found to result in reduced graft survival or graft function in the current study.

  13. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration

    OpenAIRE

    Juang, Jyuhn-Huarng; Kuo, Chien-Hung; Peng, Shih-Jung; Tang, Shiue-Cheng

    2015-01-01

    The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histolo...

  14. Effect of liver histopathology on islet cell engraftment in the model mimicking autologous islet cell transplantation.

    Science.gov (United States)

    Desai, Chirag S; Khan, Khalid M; Ma, Xiaobo; Li, Henghong; Wang, Juan; Fan, Lijuan; Chen, Guoling; Smith, Jill P; Cui, Wanxing

    2017-11-02

    The inflammatory milieu in the liver as determined by histopathology is different in individual patients undergoing autologous islet cell transplantation. We hypothesized that inflammation related to fatty-liver adversely impacts islet survival. To test this hypothesis, we used a mouse model of fatty-liver to determine the outcome of syngeneic islet transplantation after chemical pancreatectomy. Mice (C57BL/6) were fed a high-fat-diet from 6 weeks of age until attaining a weight of ≥28 grams (6-8 weeks) to produce a fatty liver (histologically > 30% fat);steatosis was confirmed with lipidomic profile of liver tissue. Islets were infused via the intra-portal route in fatty-liver and control mice after streptozotocin induction of diabetes. Outcomes were assessed by the rate of euglycemia, liver histopathology, evaluation of liver inflammation by measuring tissue cytokines IL-1β and TNF-α by RT-PCR and CD31 expression by immunohistochemistry. The difference in the euglycemic fraction between the normal liver group (90%, 9/10) and the fatty-liver group (37.5%, 3/8) was statistically significant at the 18 th day post- transplant and was maintained to the end of the study (day 28) (p = 0.019, X 2 = 5.51). Levels of TNF-α and IL-1β were elevated in fatty-liver mice (p = 0.042, p = 0.037). Compared to controls cytokine levels were elevated after islet cell transplantation and in transplanted fatty-liver mice as compared to either fatty- or islet transplant group alone (p = NS). A difference in the histochemical pattern of CD31 could not be determined. Fatty-liver creates an inflammatory state which adversely affects the outcome of autologous islet cell transplantation.

  15. Redox-Dependent Inflammation in Islet Transplantation Rejection

    Directory of Open Access Journals (Sweden)

    Jessie M. Barra

    2018-04-01

    Full Text Available Type 1 diabetes is an autoimmune disease that results in the progressive destruction of insulin-producing pancreatic β-cells inside the islets of Langerhans. The loss of this vital population leaves patients with a lifelong dependency on exogenous insulin and puts them at risk for life-threatening complications. One method being investigated to help restore insulin independence in these patients is islet cell transplantation. However, challenges associated with transplant rejection and islet viability have prevented long-term β-cell function. Redox signaling and the production of reactive oxygen species (ROS by recipient immune cells and transplanted islets themselves are key players in graft rejection. Therefore, dissipation of ROS generation is a viable intervention that can protect transplanted islets from immune-mediated destruction. Here, we will discuss the newly appreciated role of redox signaling and ROS synthesis during graft rejection as well as new strategies being tested for their efficacy in redox modulation during islet cell transplantation.

  16. Redox-Dependent Inflammation in Islet Transplantation Rejection

    Science.gov (United States)

    Barra, Jessie M.; Tse, Hubert M.

    2018-01-01

    Type 1 diabetes is an autoimmune disease that results in the progressive destruction of insulin-producing pancreatic β-cells inside the islets of Langerhans. The loss of this vital population leaves patients with a lifelong dependency on exogenous insulin and puts them at risk for life-threatening complications. One method being investigated to help restore insulin independence in these patients is islet cell transplantation. However, challenges associated with transplant rejection and islet viability have prevented long-term β-cell function. Redox signaling and the production of reactive oxygen species (ROS) by recipient immune cells and transplanted islets themselves are key players in graft rejection. Therefore, dissipation of ROS generation is a viable intervention that can protect transplanted islets from immune-mediated destruction. Here, we will discuss the newly appreciated role of redox signaling and ROS synthesis during graft rejection as well as new strategies being tested for their efficacy in redox modulation during islet cell transplantation. PMID:29740396

  17. Serum Cytokines as Biomarkers in Islet Cell Transplantation for Type 1 Diabetes.

    Directory of Open Access Journals (Sweden)

    Cornelis R van der Torren

    Full Text Available Islet cell transplantation holds a potential cure for type 1 diabetes, but many islet recipients do not reach long-lasting insulin independence. In this exploratory study, we investigated whether serum cytokines, chemokines and adipokines are associated with the clinical outcome of islet transplantation.Thirteen islet transplant patients were selected on basis of good graft function (reaching insulin independence or insufficient engraftment (insulin requiring from our cohort receiving standardized grafts and immune suppressive therapy. Patients reaching insulin independence were divided in those with continued (>12 months versus transient (<6 months insulin independence. A panel of 94 proteins including cytokines and adipokines was measured in sera taken before and at one year after transplantation using a validated multiplex immunoassay platform.Ninety serum proteins were detectable in concentrations varying markedly among patients at either time point. Thirteen markers changed after transplantation, while another seven markers changed in a clinical subpopulation. All other markers remained unaffected after transplantation under generalized immunosuppression. Patterns of cytokines could distinguish good graft function from insufficient function including IFN-α, LIF, SCF and IL-1RII before and after transplantation, by IL-16, CCL3, BDNF and M-CSF only before and by IL-22, IL-33, KIM-1, S100A12 and sCD14 after transplantation. Three other proteins (Leptin, Cathepsin L and S100A12 associated with loss of temporary graft function before or after transplantation.Distinct cytokine signatures could be identified in serum that predict or associate with clinical outcome. These serum markers may help guiding patient selection and choice of immunotherapy, or act as novel drug targets in islet transplantation.

  18. Encapsulation of pancreatic islets for transplantation in diabetes : the untouchable islets

    NARCIS (Netherlands)

    de Vos, P; Marchetti, P

    The aim of encapsulation of pancreatic islets is to transplant in the absence of immunosuppression. It is based on the principle that transplanted tissue is protected from the host immune system by an artificial membrane. Encapsulation allows for application of insulin-secreting cells of animal or

  19. Roles of Toll-like receptors in allogeneic islet transplantation.

    Science.gov (United States)

    Ro, Han; Hong, Juho; Kim, Beom Seok; Lee, Eun Won; Kim, Myung-Gyu; Han, Kyu Hyun; Yeom, Hye-Jung; Lee, Eun Mi; Jeong, Jong Cheol; Oh, Kook-Hwan; Ahn, Curie; Yang, Jaeseok

    2012-11-27

    Toll-like receptors (TLRs) are involved in the rejection of solid organ allografts. However, the roles of TLRs in islets are still controversial. We investigated the roles of TLRs in donor islets together with those in recipients in allogeneic islet transplantation. To assess the roles of TLRs in either donor islets or recipients, allogeneic islet transplantation was performed using myeloid differentiation factor 88 (MyD88)-knockout (KO), TLR4-KO, or Toll/interleukin-1 receptor domain-containing adaptor-inducing interferon-β (TRIF)-KO mice. Both polyriboinosinic polyribocytidylic acid and lipopolysaccharide (LPS) stimulation induced the mRNA expression of regulated and normal T cell expressed and secreted, interferon-γ-inducible protein-10, monocyte chemotactic protein-1, interleukin-8, and inducible nitric oxide synthase in murine islets, whereas the induction was attenuated in TRIF-KO, interferon-β promoter stimulator-1-KO, and TLR4-KO mice. When islets from MyD88-KO, TLR4-KO, or TRIF-KO C57BL/6 mice were transplanted to BALB/c recipients, graft survival was not better than that of wild-type (WT) islets. However, the survival of the MyD88-KO islet allograft was significantly prolonged when combined with anti-CD40L. In parallel, LPS stimulation in donor islets interfered with anti-CD40L blockade-mediated long-term survival of islet allografts in TLR4-KO recipients. LPS stimulation increased the perigraft infiltration of both T cells and macrophages. Then again, when islets from WT BALB/c mice were transplanted to MyD88-KO, TRIF-KO, or WT C57BL/6 mice, there was no difference in graft survival, although some of the MyD88-KO recipients obtained long-term graft survival. However, anti-CD40L prolonged graft survival significantly in MyD88-KO recipients. The absence of MyD88 in either donors or recipients decreased the perigraft infiltration of inflammatory cells when combined with anti-CD40L. TLRs in both donor islets and recipients are involved in islet allograft

  20. Successful pregnancy and delivery after simultaneous islet-kidney transplantation.

    Science.gov (United States)

    Assalino, Michela; Podetta, Michele; Demuylder-Mischler, Sandrine; Francini, Katyuska; Pernin, Nadine; Randin, Jean-Pierre; Bosco, Domenico; Andres, Axel; Berney, Thierry

    2018-04-19

    Allogeneic islet of Langerhans transplantation is a recognized beta-cell replacement therapy for patients affected by type 1 diabetes mellitus. Type 1 diabetes mellitus is a condition associated with an increased risk of adverse outcomes for pregnant women and fetuses. We report the case of a 29-year-old woman with type 1 diabetes mellitus, who underwent successful allogeneic islet transplantation with simultaneous kidney transplantation. She achieved durable insulin independence after 2 islet infusions. Pregnancy was desired and planned 2 years after the last islet infusion. Multidisciplinary monitoring of pregnancy was carried out and the immunosuppressive regimen was adapted. Euglycemia was maintained throughout pregnancy without the need for exogenous insulin. After an uneventful pregnancy, she delivered on term an otherwise healthy male child with imperforate anus that was immediately surgically corrected. In conclusion, allogeneic islet transplantation is a suitable treatment for women of childbearing age with complicated type 1 diabetes mellitus, allowing physiologic glycemic control during pregnancy with a low risk of graft loss. This target can be achieved only by a tight multidisciplinary follow-up, including immunosuppressive therapy adaptation and adequate diabetes and obstetrical monitoring. © 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.

  1. Amyloid Deposition in Transplanted Human Pancreatic Islets: A Conceivable Cause of Their Long-Term Failure

    Directory of Open Access Journals (Sweden)

    Arne Andersson

    2008-01-01

    Full Text Available Following the encouraging report of the Edmonton group, there was a rejuvenation of the islet transplantation field. After that, more pessimistic views spread when long-term results of the clinical outcome were published. A progressive loss of the β-cell function meant that almost all patients were back on insulin therapy after 5 years. More than 10 years ago, we demonstrated that amyloid deposits rapidly formed in human islets and in mouse islets transgenic for human IAPP when grafted into nude mice. It is, therefore, conceivable to consider amyloid formation as one potential candidate for the long-term failure. The present paper reviews attempts in our laboratories to elucidate the dynamics of and mechanisms behind the formation of amyloid in transplanted islets with special emphasis on the impact of long-term hyperglycemia.

  2. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration.

    Science.gov (United States)

    Juang, Jyuhn-Huarng; Kuo, Chien-Hung; Peng, Shih-Jung; Tang, Shiue-Cheng

    2015-02-01

    The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histology with cell tracing to reveal the participation of Schwann cells and pericytes in mouse islet transplantation. Longitudinal studies of the grafts under the kidney capsule identify that the donor Schwann cells and pericytes re-associate with the engrafted islets at the peri-graft and perivascular domains, respectively, indicating their adaptability in transplantation. Based on the morphological proximity and cellular reactivity, we propose that the new islet microenvironment should include the peri-graft Schwann cell sheath and perivascular pericytes as an integral part of the new tissue.

  3. Improving pancreatic islet in vitro functionality and transplantation efficiency by using heparin mimetic peptide nanofiber gels.

    Science.gov (United States)

    Uzunalli, Gozde; Tumtas, Yasin; Delibasi, Tuncay; Yasa, Oncay; Mercan, Sercan; Guler, Mustafa O; Tekinay, Ayse B

    2015-08-01

    Pancreatic islet transplantation is a promising treatment for type 1 diabetes. However, viability and functionality of the islets after transplantation are limited due to loss of integrity and destruction of blood vessel networks. Thus, it is important to provide a proper mechanically and biologically supportive environment for enhancing both in vitro islet culture and transplantation efficiency. Here, we demonstrate that heparin mimetic peptide amphiphile (HM-PA) nanofibrous network is a promising platform for these purposes. The islets cultured with peptide nanofiber gel containing growth factors exhibited a similar glucose stimulation index as that of the freshly isolated islets even after 7 days. After transplantation of islets to STZ-induced diabetic rats, 28 day-long monitoring displayed that islets that were transplanted in HM-PA nanofiber gels maintained better blood glucose levels at normal levels compared to the only islet transplantation group. In addition, intraperitoneal glucose tolerance test revealed that animals that were transplanted with islets within peptide gels showed a similar pattern with the healthy control group. Histological assessment showed that islets transplanted within peptide nanofiber gels demonstrated better islet integrity due to increased blood vessel density. This work demonstrates that using the HM-PA nanofiber gel platform enhances the islets function and islet transplantation efficiency both in vitro and in vivo. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Isolation of Human Islets for Autologous Islet Transplantation in Children and Adolescents with Chronic Pancreatitis

    Directory of Open Access Journals (Sweden)

    Rita Bottino

    2012-01-01

    Full Text Available Chronic pancreatitis is an inflammatory disease of the pancreas that causes permanent changes in the function and structure of the pancreas. It is most commonly a complication of cystic fibrosis or due to a genetic predisposition. Chronic pancreatitis generally presents symptomatically as recurrent abdominal pain, which becomes persistent over time. The pain eventually becomes disabling. Once specific medical treatments and endoscopic interventions are no longer efficacious, total pancreatectomy is the alternative of choice for helping the patient achieve pain control. While daily administrations of digestive enzymes cannot be avoided, insulin-dependent diabetes can be prevented by transplanting the isolated pancreatic islets back to the patient. The greater the number of islets infused, the greater the chance to prevent or at least control the effects of surgical diabetes. We present here a technical approach for the isolation and preservation of the islets proven to be efficient to obtain high numbers of islets, favoring the successful treatment of young patients.

  5. Financial issues constraining the use of pancreata recovered for islet transplantation: a white paper.

    Science.gov (United States)

    Markmann, J F; Kaufman, D B; Ricordi, C; Schwab, P M; Stock, P G

    2008-08-01

    Islet transplantation is a very promising therapy for select patients with type 1 diabetes. Continued clinical investigation is required to define the long-term safety and efficacy outcomes before the procedure will be accepted as a standard of care even for those with the most severe manifestations of diabetes. Threatening successful accomplishment of these and other innovative studies designed to advance the field are the complex financial cost accounting issues that pose undue burden on organ procurement organizations and transplant centers trying to manage the costs of the pancreata from deceased donors needed to isolate islets. Compounding the problem is the recent ruling by CMS regarding 'intent to transplant' (CMS-1543-R Dec. 21, 2006: Allocation of Donor Acquisition Costs Incurred by Organ Procurement Organizations) that does not account for the clinical need to complete the manufacturing process for islets before suitability and transplant intent of the pancreata involved can be determined. We provide a consensus document supported by a diverse group of stakeholders in islet transplantation to suggest actions to address this problem.

  6. Comparison of therapeutic characteristics of islet cell transplantation simultaneous with pancreatic mesenchymal stem cell transplantation in rats with Type 1 diabetes mellitus.

    Science.gov (United States)

    Unsal, Ilknur Ozturk; Ginis, Zeynep; Pinarli, Ferda Alparslan; Albayrak, Aynur; Cakal, Erman; Sahin, Mustafa; Delibasi, Tuncay

    2015-06-01

    Although, pancreas islet call transplantation is a new, promising method for type 1 diabetic patients, it remains as an experimental procedure applied in selected patients. The present study aimed to investigate effect of pancreatic mesenchymal stem cell transplantation simultaneous with islet cell transplantation on islet liveliness and thus on the treatment of diabetes in type 1 diabetic rats. The study used Wistar Albino Rats and was performed in a total of four groups [control (G1), mesenchymal stem cell (G2), islet (G3) and islet + mesencymal stem cell (G4)] each including 8 rats. Blood glucose level of the rats, in which diabetes model has been created using streptozotocin, was measured after 72 h. Blood samples were obtained from the rats 30 days after transplantation and then, their livers and pancreases were kept in 10% formaldehyde and the experiment was ended. Following staining with H&E, they were morphologically evaluated under a light microscope. Change in mean blood glucose level was statistically significant in G3 and G4 versus G1 and G2 (p = 0.001, p islet cells in the pancreases of the rats was higher in G4; difference between the groups was statistically significant (p Transplantation of islet cells together with mesenchymal stem cells showed beneficial effects in terms of prolonging survival of islet grafts suggesting that transplantation of mesenchymal stem cells together with islet cells during clinical islet transplantation may be beneficial in increasing the number of noninsulin-dependent patients in Type 1 diabetes.

  7. Comparison of the Ovary and Kidney as Sites for Islet Transplantation in Diabetic Rats.

    Science.gov (United States)

    Karakose, M; Pinarli, F A; Arslan, M S; Boyuk, G; Boztok, B; Albayrak, A; Ulus, A T; Cakal, E; Delibasi, T

    2016-01-01

    Currently, the most commonly used site for clinical islet transplantation is the liver although it is far from being an ideal site. Low oxygen tension and the induction of an inflammatory response impair islet implantation and lead to significant early loss of islet. The present study aimed to investigate and compare the efficacy of islet transplantation to the ovary and kidney subcapsule in diabetic rats. The study was performed with 3 groups of rats (control, ovary, and kidney subcapsule) including 6 Sprague female rats each. Diabetes model was created with the use of streptozotocin, and blood glucose levels of the rats were measured after 72 hours. Thirty days after the transplantation, blood samples were obtained from the rats, and then pancreas, kidney, and ovary specimens were fixed in 10% formaldehyde and the experiment completed. After staining with hematoxylin and eosin, the tissue samples were morphologically evaluated by a specialist histopathologist. Changes in mean blood glucose and C-peptide levels were statistically significant in the ovary and kidney subcapsule groups. Histologic examination revealed that granulosus insulin-bearing cells were detected in the islet grafts of both ovary and kidney subcapsule groups. The renal subcapsule group had inflammation signs on histologic examination. The islet cells of both ovary and renal subcapsule groups had no vacuolization. We showed that the ovary might be a new site for islet transplantation. Further research should be done on whether the initial results of this study can be reproduced in larger numbers of animal models and eventually in humans. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Effects of fluid dynamic stress on fracturing of cell-aggregated tissue during purification for islets of Langerhans transplantation

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    Shintaku, H; Kawano, S [Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan); Okitsu, T [Transplantation Unit, Kyoto University Hospital, Kawara-cho Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Matsumoto, S [Baylor Research Institute Islet Cell Laboratory, 1400 Eight Avenue, Fort Worth, TX 76104 (United States); Suzuki, T; Kanno, I; Kotera, H [Department of Microengineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)], E-mail: shintaku@me.es.osaka-u.ac.jp

    2008-06-07

    Among clinical treatments for type 1 diabetes mellitus, the transplantation of islets of Langerhans to the portal vein of the hepar is a commonly used treatment for glucose homeostasis. Islet purification using the density gradient of a solution in a centrifuge separator is required for safety and efficiency. In the purification, the number of tissues to be transplanted is reduced by removing the acinar tissue and gathering the islet from the digest of pancreas. However, the mechanical effects on the fracture of islets in the centrifuge due to fluid dynamic stress are a serious problem in the purification process. In this study, a preliminary experiment using a cylindrical rotating viscometer with a simple geometry is conducted in order to systematically clarify the effect of fluid dynamic stress on the fracture of islets. The effects of fluid dynamic stress on the islet configuration is quantitatively measured for various flow conditions, and a predictive fracture model is developed based on the experimental results. Furthermore, in the practical purification process in the COBE (Gambro BCT), which is widely used in clinical applications, we perform a numerical analysis of the fluid dynamic stress based on Navier-Stokes equations to estimate the stress conditions for islets. Using the fracture model and numerical analysis, the islet fracture characteristics using the COBE are successfully investigated. The results obtained in this study provide crucial information for the purification of islets by centrifuge in practical and clinical applications.

  9. Effects of fluid dynamic stress on fracturing of cell-aggregated tissue during purification for islets of Langerhans transplantation

    International Nuclear Information System (INIS)

    Shintaku, H; Kawano, S; Okitsu, T; Matsumoto, S; Suzuki, T; Kanno, I; Kotera, H

    2008-01-01

    Among clinical treatments for type 1 diabetes mellitus, the transplantation of islets of Langerhans to the portal vein of the hepar is a commonly used treatment for glucose homeostasis. Islet purification using the density gradient of a solution in a centrifuge separator is required for safety and efficiency. In the purification, the number of tissues to be transplanted is reduced by removing the acinar tissue and gathering the islet from the digest of pancreas. However, the mechanical effects on the fracture of islets in the centrifuge due to fluid dynamic stress are a serious problem in the purification process. In this study, a preliminary experiment using a cylindrical rotating viscometer with a simple geometry is conducted in order to systematically clarify the effect of fluid dynamic stress on the fracture of islets. The effects of fluid dynamic stress on the islet configuration is quantitatively measured for various flow conditions, and a predictive fracture model is developed based on the experimental results. Furthermore, in the practical purification process in the COBE (Gambro BCT), which is widely used in clinical applications, we perform a numerical analysis of the fluid dynamic stress based on Navier-Stokes equations to estimate the stress conditions for islets. Using the fracture model and numerical analysis, the islet fracture characteristics using the COBE are successfully investigated. The results obtained in this study provide crucial information for the purification of islets by centrifuge in practical and clinical applications

  10. Effect of the Diabetic State on Islet Engraftment and Function in a Large Animal Model of Islet-Kidney Transplantation.

    Science.gov (United States)

    Vallabhajosyula, Prashanth; Hirakata, Atsushi; Weiss, Matthew; Griesemer, Adam; Shimizu, Akira; Hong, Hanzhou; Habertheuer, Andreas; Tchipashvili, Vaja; Yamada, Kazuhiko; Sachs, David H

    2017-11-01

    In islet transplantation, in addition to immunologic and ischemic factors, the diabetic/hyperglycemic state of the recipient has been proposed, although not yet validated, as a possible cause of islet toxicity, contributing to islet loss during the engraftment period. Using a miniature swine model of islet transplantation, we have now assessed the effect of a persistent state of hyperglycemia on islet engraftment and subsequent function. An islet-kidney (IK) model previously described by our laboratory was utilized. Three experimental donor animals underwent total pancreatectomy and autologous islet transplantation underneath the renal capsule to prepare an IK at a load of ≤1,000 islet equivalents (IE)/kg donor weight, leading to a chronic diabetic state during the engraftment period (fasting blood glucose >250 mg/dL). Three control donor animals underwent partial pancreatectomy (sufficient to maintain normoglycemia during islet engraftment period) and IK preparation. As in vivo functional readout for islet engraftment, the IKs were transplanted across an immunologic minor or class I mismatch barrier into diabetic, nephrectomized recipients at an islet load of ∼4,500 IE/kg recipient weight. A 12-d course of cyclosporine was administered for tolerance induction. All experimental donors became diabetic and showed signs of end organ injury, while control donors maintained normoglycemia. All recipients of IK from both experimental and control donors achieved glycemic control over long-term follow-up, with reversal of diabetic nephropathy and with similar glucose tolerance tests. In this preclinical, large animal model, neither islet engraftment nor subsequent long-term islet function after transplantation appear to be affected by the diabetic state.

  11. Delayed revascularization of islets after transplantation by IL-6 blockade in pig to non-human primate islet xenotransplantation model.

    Science.gov (United States)

    Min, Byoung-Hoon; Shin, Jun-Seop; Kim, Jong-Min; Kang, Seong-Jun; Kim, Hyun-Je; Yoon, Il-Hee; Park, Su-Kyoung; Choi, Ji-Won; Lee, Min-Suk; Park, Chung-Gyu

    2018-01-01

    Pancreatic islet transplantation is currently proven as a promising treatment for type 1 diabetes patients with labile glycemic control and severe hypoglycemia unawareness. Upon islet transplantation, revascularization is essential for proper functioning of the transplanted islets. As IL-6 is important for endothelial cell survival and systemic inflammation related to xenograft, the effect of IL-6 receptor antagonist, tocilizumab, on revascularization of the transplanted islets was examined in pig to non-human primate islet xenotransplantation model. Also, the endothelial cell origin in a new vessel of the transplanted pig islets was determined. Pig islets were isolated from designated pathogen-free (DPF) SNU miniature pigs and transplanted via portal vein into five streptozotocin-induced diabetic monkeys. One group (n = 2, basal group) was treated with anti-thymoglobulin (ATG), anti-CD40 antibody (2C10R4), sirolimus, and tacrolimus, and the other group was additionally given tocilizumab on top of basal immunosuppression (n = 3, Tocilizumab group). To confirm IL-6 blocking effect, C-reactive protein (CRP) levels and serum IL-6 concentration were measured. Scheduled biopsy of the margin of the posterior segment right lobe inferior of the liver was performed at 3 weeks after transplantation to assess the degree of revascularization of the transplanted islets. Immunohistochemical staining using anti-insulin, anti-CD31 antibodies, and lectin IB4 was conducted to find the origin of endothelial cells in the islet graft. CRP significantly increased at 1~2 days after transplantation in Basal group, but not in Tocilizumab group, and higher serum IL-6 concentration was measured in latter group, showing the biological potency of tocilizumab. In Basal group, well-developed endothelial cells were observed on the peri- and intraislet area, whereas the number of CD31 + cells in the intraislet space was significantly reduced in Tocilizumab group. Finally, new endothelial

  12. Experimental treatment of diabetic mice with microencapsulated rat islet cells transplantation

    International Nuclear Information System (INIS)

    Luo Yun; Xue Yilong; Li Yanling; Li Xinjian

    2006-01-01

    To observe treatment effects of diabetic mice with microcapsulated and non-microcapsulated rat islet cell transplantation, pancreas of SD rat was perfused with collagenase through cloledchus, and then the pancreatic tissues were isolated and digested. Histopaque-1077 was used to purify the digested pancreas. Islet cells were collected and implanted into the peritoneal cavity of diabetic mice. The isolated islets had a response upon glucose stimulation. When the microcapsulated islets and non- microcapsulated islets were transplanted into diabetic mices the high blood glucose level could be decreased to normal. The normal blood glucose level in the diabetic mice transpanted with microcapsulated islets could be maintained for over 30 days,but it could be mainlained only for 2-3 days in the diabetic mice transplanted with non-microcapsulated islets. Thus it is believed that microcapsulated islet cell transplantation exerts good effect on diabetic mice and the microcapsules possessed good immunoisolating function. (authors)

  13. Role of Natural Killer Cells in the Innate Immune System After Intraportal Islet Transplantation in Mice.

    Science.gov (United States)

    Saeki, Y; Ishiyama, K; Ishida, N; Tanaka, Y; Ohdan, H

    Both liver natural killer (NK) and NK T cells of the innate immune system play a crucial role in islet graft loss after intraportal islet transplantation, although a relationship between NK and NK T cells in islet loss has not been proven. In this study, we investigated the role of NK cells in the innate immune system in islet graft loss after intraportal islet transplantation. To investigate the involvement of liver NK cells in islet destruction, we assessed the differences in graft survival after intraportal islet transplantation between CD1d -/- diabetic mice and NK cell-depleted CD1d -/- diabetic mice. The transplantation of 400 islets into the liver was sufficient to reverse hyperglycemia in wild-type diabetic mice (100%, 4/4). However, normoglycemia could not be achieved when 200 islets were transplanted (0%, 0/4). In contrast, intraportal transplantation of 200 islets in NK cell-depleted CD1d -/- diabetic mice ameliorated hyperglycemia in 71% of cases (5/7), whereas transplantation of the same number of islets in CD1d -/- diabetic mice did not (0%, 0/4). Histologic findings also confirmed that intact islets were observed in NK cell-depleted CD1d -/- diabetic mice, but were difficult to observe in CD1d -/- diabetic mice. The involvement of liver NK cells in the innate immune system related to islet graft loss after intraportal islet transplantation is revealed by improved graft survival and function in NK cell-depleted CD1d -/- diabetic mice. Our data reveal that regulation of NK cell activity is particularly important when insufficient islet numbers are used for transplantation. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Human pancreatic islet transplantation: an update and description of the establishment of a pancreatic islet isolation laboratory.

    Science.gov (United States)

    Rheinheimer, Jakeline; Bauer, Andrea C; Silveiro, Sandra P; Estivalet, Aline A F; Bouças, Ana P; Rosa, Annelise R; Souza, Bianca M de; Oliveira, Fernanda S de; Cruz, Lavínia A; Brondani, Letícia A; Azevedo, Mirela J; Lemos, Natália E; Carlessi, Rodrigo; Assmann, Taís S; Gross, Jorge L; Leitão, Cristiane B; Crispim, Daisy

    2015-04-01

    Type 1 diabetes mellitus (T1DM) is associated with chronic complications that lead to high morbidity and mortality rates in young adults of productive age. Intensive insulin therapy has been able to reduce the likelihood of the development of chronic diabetes complications. However, this treatment is still associated with an increased incidence of hypoglycemia. In patients with "brittle T1DM", who have severe hypoglycemia without adrenergic symptoms (hypoglycemia unawareness), islet transplantation may be a therapeutic option to restore both insulin secretion and hypoglycemic perception. The Edmonton group demonstrated that most patients who received islet infusions from more than one donor and were treated with steroid-free immunosuppressive drugs displayed a considerable decline in the initial insulin independence rates at eight years following the transplantation, but showed permanent C-peptide secretion, which facilitated glycemic control and protected patients against hypoglycemic episodes. Recently, data published by the Collaborative Islet Transplant Registry (CITR) has revealed that approximately 50% of the patients who undergo islet transplantation are insulin independent after a 3-year follow-up. Therefore, islet transplantation is able to successfully decrease plasma glucose and HbA1c levels, the occurrence of severe hypoglycemia, and improve patient quality of life. The goal of this paper was to review the human islet isolation and transplantation processes, and to describe the establishment of a human islet isolation laboratory at the Endocrine Division of the Hospital de Clínicas de Porto Alegre - Rio Grande do Sul, Brazil.

  15. Immunosuppressive effect of compound K on islet transplantation in an STZ-induced diabetic mouse model.

    Science.gov (United States)

    Ma, Peng-Fei; Jiang, Jie; Gao, Chang; Cheng, Pan-Pan; Li, Jia-Li; Huang, Xin; Lin, Ying-Ying; Li, Qing; Peng, Yuan-Zheng; Cai, Mei-Chun; Shao, Wei; Zhu, Qi; Han, Sai; Qin, Qing; Xia, Jun-Jie; Qi, Zhong-Quan

    2014-10-01

    Islet transplantation is a therapeutic option for type 1 diabetes, but its long-term success is limited by islet allograft survival. Many factors imperil islet survival, especially the adverse effects and toxicity due to clinical immunosuppressants. Compound (Cpd) K is a synthesized analog of highly unsaturated fatty acids from Isatis tinctoria L. (Cruciferae). Here we investigated the therapeutic effect of Cpd K in diabetic mice and found that it significantly prolonged islet allograft survival with minimal adverse effects after 10 days. Furthermore, it reduced the proportion of CD4(+) and CD8(+) T cells in spleen and lymph nodes, inhibited inflammatory cell infiltration in allografts, suppressed serum interleukin-2 and interferon-γ secretion, and increased transforming growth factor-β and Foxp3 mRNA expression. Surprisingly, Cpd K and rapamycin had a synergistic effect. Cpd K suppressed proliferation of naïve T cells by inducing T-cell anergy and promoting the generation of regulatory T cells. In addition, nuclear factor-κB signaling was also blocked. Taken together, these findings indicate that Cpd K may have a potential immunosuppressant effect on islet transplantation. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  16. On the use of [18F]DOPA as an imaging biomarker for transplanted islet mass

    International Nuclear Information System (INIS)

    Eriksson, Olof; Mintz, Akiva; Liu, Chengyang; Yu, Ming; Naji, Ali; Alavi, Abass

    2014-01-01

    Islet transplantation is being developed as a potential cure for patients with type 1 diabetes. There is a need for non-invasive imaging techniques for the quantification of transplanted islets, as current transplantation sites are associated with a substantial loss of islet viability. The dopaminergic metabolic pathway is present in the islets; therefore, we propose Fluorine-18 labeled L-3,4-dihydroxyphenylalanine ([ 18 F]DOPA) as a biomarker for transplanted islet mass. The expression of enzymes involved in the dopaminergic metabolic pathway was investigated in both native and transplanted human islets. The specific uptake of [ 18 F]DOPA in islets and immortalized beta cells was studied in vitro by selective blocking of dopa decarboxylase (DDC). Initial in vivo positron emission tomography (PET) imaging of viable subcutaneous human islets was performed using [ 18 F]DOPA. DDC and vesicular monoamine transporter 2 are co-localized with insulin in the native human pancreas, and the expression is retained after transplantation. Islet uptake of the [ 18 F]DOPA could be modulated by inhibiting DDC, indicating that the uptake followed the normal dopaminergic metabolic pathway. In vivo imaging revealed [ 18 F]DOPA uptake at the site of the functional islet graft. Based on the in vitro and in vivo results presented in this study, we propose to further validate [ 18 F]DOPA-PET as a sensitive imaging modality for imaging extrahepatically transplanted islets. (author)

  17. Harnessing the Foreign Body Reaction in Marginal Mass Device-less Subcutaneous Islet Transplantation in Mice.

    Science.gov (United States)

    Pepper, Andrew R; Pawlick, Rena; Bruni, Antonio; Gala-Lopez, Boris; Wink, John; Rafiei, Yasmin; Bral, Mariusz; Abualhassan, Nasser; Shapiro, A M James

    2016-07-01

    Islet transplantation is a successful β-cell replacement therapy for selected patients with type 1 diabetes mellitus. However, despite early insulin independence, long-term graft attrition gradually reverts recipients to exogenous insulin dependency. Undoubtedly, as insulin producing stem cell therapies progress, a transplant site that is retrievable is desirable. This prerequisite is currently incompatible with intrahepatic islet transplantation. Herein, we evaluate the functional capacity of a prevascularized subcutaneous site to accommodate marginal islet mass transplantation in mice. Syngeneic mouse islets (150) were transplanted either under the kidney capsule (KC), into a prevascularized subcutaneous device-less (DL) site, or into the unmodified subcutaneous (SC) tissue. The DL site was created 4 weeks before diabetes induction and islet transplantation through the transient placement of a 5-Fr vascular catheter. Recipient mice were monitored for glycemic control and intraperitoneal glucose tolerance. A marginal islet mass transplanted into the DL site routinely reversed diabetes (n = 13 of 18) whereas all SC islet recipients failed to restore glycemic control (n = 0 of 10, P islet-KC mice (n = 15 of 16) became euglycemic posttransplant. The DL recipients' glucose profiles were comparable to KC islet grafts, postintrapertioneal glucose tolerance testing, whereas SC recipients remained hyperglycemic postglucose challenge. All normoglycemic mice maintained graft function for 100 days until graft retrieval. DL and KC islet grafts stained positively for insulin, microvessels, and a collagen scaffold. The device-less prevascularized approach supports marginal mass islet engraftment in mice.

  18. Long-term Efficacy and Biocompatibility of Encapsulated Islet Transplantation With Chitosan-Coated Alginate Capsules in Mice and Canine Models of Diabetes.

    Science.gov (United States)

    Yang, Hae Kyung; Ham, Dong-Sik; Park, Heon-Seok; Rhee, Marie; You, Young Hye; Kim, Min Jung; Shin, Juyoung; Kim, On-You; Khang, Gilson; Hong, Tae Ho; Kim, Ji-Won; Lee, Seung-Hwan; Cho, Jae-Hyoung; Yoon, Kun-Ho

    2016-02-01

    Clinical application of encapsulated islet transplantation is hindered by low biocompatibility of capsules leading to pericapsular fibrosis and decreased islet viability. To improve biocompatibility, we designed a novel chitosan-coated alginate capsules and compared them to uncoated alginate capsules. Alginate capsules were formed by crosslinking with BaCl2, then they were suspended in chitosan solution for 10 minutes at pH 4.5. Xenogeneic islet transplantation, using encapsulated porcine islets in 1,3-galactosyltransferase knockout mice, and allogeneic islet transplantation, using encapsulated canine islets in beagles, were performed without immunosuppressants. The chitosan-alginate capsules showed similar pore size, islet viability, and insulin secretory function compared to alginate capsules, in vitro. Xenogeneic transplantation of chitosan-alginate capsules demonstrated a trend toward superior graft survival (P = 0.07) with significantly less pericapsular fibrosis (cell adhesion score: 3.77 ± 0.41 vs 8.08 ± 0.05; P transplantation. Allogeneic transplantation of chitosan-alginate capsules normalized the blood glucose level up to 1 year with little evidence of pericapsular fibrotic overgrowth on graft explantation. The efficacy and biocompatibility of chitosan-alginate capsules were demonstrated in xenogeneic and allogeneic islet transplantations using small and large animal models of diabetes. This capsule might be a potential candidate applicable in the treatment of type 1 diabetes mellitus patients, and further studies in nonhuman primates are required.

  19. Current principles and practice in autologous intraportal islet transplantation: a meta-analysis of the technical considerations.

    Science.gov (United States)

    Kumar, Rohan; Chung, Wen Yuan; Dennison, Ashley Robert; Garcea, Giuseppe

    2016-04-01

    Autologous islet transplantation (IAT) following pancreatectomy is now a recognized, albeit highly specialized procedure carried out in a small number of centers worldwide. Current clinical principles and best practice with emphasis on examining the technical aspects of surgery in centers with significant IAT experience are reviewed. Literature search for studies discussing any technical aspect of pancreatectomy with intraportal IAT was included. Thirty-five papers were included; all were single-center case series. The indications, surgical approach to pancreatectomy with IAT, islet yield, static pancreas preservation prior to islet digestion, portal vein access, absolute islet infusion volumes, and portal venous pressure changes during transfusion evaluated. IAT is considered a "last resort" when alternative approaches have been exhausted. Pre-morbid histology and prior surgical drainage adversely influence islet yields and may influence the clinical decision to perform pancreatectomy and IAT. Following pancreas digestion, absolute numbers of islets recovered and smaller islet size predict rates of insulin independence following IAT. Islet volumes and portal venous pressure changes are important factors for the development of complications. Surgical access for IAT includes intra-operative, immediate or delayed infusion via an "exteriorized" vein, and radiological percutaneous approaches. Delayed infusion can be combined with pancreas preservation techniques prior to islet isolation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Extracellular Matrix and Growth Factors Improve the Efficacy of Intramuscular Islet Transplantation.

    Directory of Open Access Journals (Sweden)

    Haruyuki Tsuchiya

    Full Text Available The efficacy of intramuscular islet transplantation is poor despite being technically simple, safe, and associated with reduced rates of severe complications. We evaluated the efficacy of combined treatment with extracellular matrix (ECM and growth factors in intramuscular islet transplantation.Male BALB/C mice were used for the in vitro and transplantation studies. The following three groups were evaluated: islets without treatment (islets-only group, islets embedded in ECM with growth factors (Matrigel group, and islets embedded in ECM without growth factors [growth factor-reduced (GFR Matrigel group]. The viability and insulin-releasing function of islets cultured for 96 h were significantly improved in Matrigel and GFR Matrigel groups compared with the islets-only group.Blood glucose and serum insulin levels immediately following transplantation were significantly improved in the Matrigel and GFR Matrigel groups and remained significantly improved in the Matrigel group at postoperative day (POD 28. On histological examination, significantly decreased numbers of TdT-mediated deoxyuridine triphosphate-biotin nick end labeling-positive islet cells and significantly increased numbers of Ki67-positive cells were observed in the Matrigel and GFR Matrigel groups at POD 3. Peri-islet revascularization was most prominent in the Matrigel group at POD 14.The efficacy of intramuscular islet transplantation was improved by combination treatment with ECM and growth factors through the inhibition of apoptosis, increased proliferation of islet cells, and promotion of revascularization.

  1. Extracellular Matrix and Growth Factors Improve the Efficacy of Intramuscular Islet Transplantation.

    Science.gov (United States)

    Tsuchiya, Haruyuki; Sakata, Naoaki; Yoshimatsu, Gumpei; Fukase, Masahiko; Aoki, Takeshi; Ishida, Masaharu; Katayose, Yu; Egawa, Shinichi; Unno, Michiaki

    2015-01-01

    The efficacy of intramuscular islet transplantation is poor despite being technically simple, safe, and associated with reduced rates of severe complications. We evaluated the efficacy of combined treatment with extracellular matrix (ECM) and growth factors in intramuscular islet transplantation. Male BALB/C mice were used for the in vitro and transplantation studies. The following three groups were evaluated: islets without treatment (islets-only group), islets embedded in ECM with growth factors (Matrigel group), and islets embedded in ECM without growth factors [growth factor-reduced (GFR) Matrigel group]. The viability and insulin-releasing function of islets cultured for 96 h were significantly improved in Matrigel and GFR Matrigel groups compared with the islets-only group. Blood glucose and serum insulin levels immediately following transplantation were significantly improved in the Matrigel and GFR Matrigel groups and remained significantly improved in the Matrigel group at postoperative day (POD) 28. On histological examination, significantly decreased numbers of TdT-mediated deoxyuridine triphosphate-biotin nick end labeling-positive islet cells and significantly increased numbers of Ki67-positive cells were observed in the Matrigel and GFR Matrigel groups at POD 3. Peri-islet revascularization was most prominent in the Matrigel group at POD 14. The efficacy of intramuscular islet transplantation was improved by combination treatment with ECM and growth factors through the inhibition of apoptosis, increased proliferation of islet cells, and promotion of revascularization.

  2. Imatinib prevents beta cell death in vitro but does not improve islet transplantation outcome.

    Science.gov (United States)

    King, Aileen J F; Griffiths, Lisa A; Persaud, Shanta J; Jones, Peter M; Howell, Simon L; Welsh, Nils

    2016-05-01

    Introduction Improving islet transplantation outcome could not only bring benefits to individual patients but also widen the patient pool to which this life-changing treatment is available. Imatinib has previously been shown to protect beta cells from apoptosis in a variety of in vitro and in vivo models. The aim of this study was to investigate whether imatinib could be used to improve islet transplantation outcome. Methods Islets were isolated from C57Bl/6 mice and pre-cultured with imatinib prior to exposure to streptozotocin and cytokines in vitro. Cell viability and glucose-induced insulin secretion were measured. For transplantation experiments, islets were pre-cultured with imatinib for either 72 h or 24 h prior to transplantation into streptozotocin-diabetic C57Bl/6 mice. In one experimental series mice were also administered imatinib after islet transplantation. Results Imatinib partially protected islets from beta cell death in vitro. However, pre-culturing islets in imatinib or administering the drug to the mice in the days following islet transplantation did not improve blood glucose concentrations more than control-cultured islets. Conclusion Although imatinib protected against beta cell death from cytokines and streptozotocin in vitro, it did not significantly improve syngeneic islet transplantation outcome.

  3. Bibliometric analysis of the top-cited articles on islet transplantation.

    Science.gov (United States)

    Pu, Qiang-Hong; Lyu, Qiu-Ju; Liu, Huan; Fan, Kai-Hua

    2017-11-01

    To identify and characterize the top-cited articles in the field of islet transplantation. We used the Science Citation Index Expanded database to identify the most frequently cited articles published after 1900. Articles were evaluated using the following characteristics: citation number, publication year, study design, references, country and institution of origin, authorship, and journal. Keyword analysis and citation networks were used to analyze research trends. The most frequently cited articles received between 146 and 2988 citations; the median was 291. All of the most frequently cited articles were published between 1972 and 2012, and 85 articles were published after 1990. The most popular study design involved basic science (75 articles). The leading countries were the United States (US) and Canada, and the leading institutions were the University of Alberta, Canada, and the University of Minnesota, in the US. Journals specializing in diabetes or transplantation published more than half of the articles (n = 53, 52%), with the journal Diabetes publishing the largest number (n = 30). No association was found between a journal's impact factor and the number of top-cited articles it published. There was no correlation between the number of citations and the number of years since publication, authors, participating institutions, or countries involved. Top-cited articles focused on 2 themes: the use of antirejection immunotherapy or biocompatible encapsulations to prolong graft survival, and assessments of the efficacy of islet transplants, in particular, islet allografts. Our study can help researchers to identify and decipher the characteristics of top-cited articles in the field of islet transplantation. Just as clinically successful allografts are carried out using the Edmonton protocol, autografts and xenografts should be similarly strengthened to solve problems relating to immune rejection and islet sources, respectively.

  4. Insulin-Like growth factor-II (IGF-II) prevents proinflammatory cytokine-induced apoptosis and significantly improves islet survival after transplantation.

    Science.gov (United States)

    Hughes, Amy; Mohanasundaram, Daisy; Kireta, Svjetlana; Jessup, Claire F; Drogemuller, Chris J; Coates, P Toby H

    2013-03-15

    The early loss of functional islet mass (50-70%) due to apoptosis after clinical transplantation contributes to islet allograft failure. Insulin-like growth factor (IGF)-II is an antiapoptotic protein that is highly expressed in β-cells during development but rapidly decreases in postnatal life. We used an adenoviral (Ad) vector to overexpress IGF-II in isolated rat islets and investigated its antiapoptotic action against exogenous cytokines interleukin-1β- and interferon-γ-induced islet cell death in vitro. Using an immunocompromised marginal mass islet transplant model, the ability of Ad-IGF-II-transduced rat islets to restore euglycemia in nonobese diabetic/severe combined immunodeficient diabetic recipients was assessed. Ad-IGF-II transduction did not affect islet viability or function. Ad-IGF-II cytokine-treated islets exhibited decreased cell death (40% ± 2.8%) versus Ad-GFP and untransduced control islets (63.2% ± 2.5% and 53.6% ± 2.3%, respectively). Ad-IGF-II overexpression during cytokine treatment resulted in a marked reduction in terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive apoptotic cells (8.3% ± 1.4%) versus Ad-GFP control (41% ± 4.2%) and untransduced control islets (46.5% ± 6.2%). Western blot analysis confirmed that IGF-II inhibits apoptosis via activation of the phosphatidylinositol 3-kinase/Akt signaling pathway. Transplantation of IGF-II overexpressing islets under the kidney capsule of diabetic mice restored euglycemia in 77.8% of recipients compared with 18.2% and 47.5% of Ad-GFP and untransduced control islet recipients, respectively (Pislet transplant outcomes in vivo. Antiapoptotic gene transfer is a potentially powerful tool to improve islet survival after transplantation.

  5. Glycemia, Hypoglycemia, and Costs of Simultaneous Islet-Kidney or Islet After Kidney Transplantation Versus Intensive Insulin Therapy and Waiting List for Islet Transplantation.

    Science.gov (United States)

    Gerber, Philipp A; Locher, Rebecca; Zuellig, Richard A; Tschopp, Oliver; Ajdler-Schaeffler, Evelyne; Kron, Philipp; Oberkofler, Christian; Brändle, Michael; Spinas, Giatgen A; Lehmann, Roger

    2015-10-01

    Long-term data of patients with type 1 diabetes mellitus (T1D) after simultaneous islet-kidney (SIK) or islet-after-kidney transplantation (IAK) are rare and have never been compared to intensified insulin therapy (IIT). Twenty-two patients with T1D and end-stage renal failure undergoing islet transplantation were compared to 70 patients matched for age and diabetes duration treated with IIT and to 13 patients with kidney transplantation alone or simultaneous pancreas-kidney after loss of pancreas function (waiting list for IAK [WLI]). Glycemic control, severe hypoglycemia, insulin requirement, and direct medical costs were analyzed. Glycated hemoglobin decreased significantly from 8.2 ± 1.5 to 6.7 ± 0.9% at the end of follow-up (mean 7.2 ± 2.5 years) in the SIK/IAK and remained constant in IIT (7.8 ± 1.0% and 7.6 ± 1.0) and WLI (7.8 ± 0.8 and 7.9 ± 1.0%). Daily insulin requirement decreased from 0.53 ± 0.15 to 0.29 ± 0.26 U/kg and remained constant in IIT (0.59 ± 0.19 and 0.58 ± 0.23 U/kg) and in WLI (0.76 ± 0.28 and 0.73 ± 0.11 U/kg). Severe hypoglycemia dropped in SIK/IAK from 4.5 ± 9.7 to 0.3 ± 0.7/patient-year and remained constant in IIT (0.1 ± 0.7 and 0.2 ± 0.8/patient-year). Detailed cost analysis revealed US $57,525 of additional cost for islet transplantation 5 years after transplantation. Based on a 5- and 10-year analysis, cost neutrality is assumed to be achieved 15 years after transplantation. This long-term cohort with more than 7 years of follow-up shows that glycemic control in patients with T1D after SIK/IAK transplantation improved, and the rate of severe hypoglycemia decreased significantly as compared to control groups. Cost analysis revealed that islet transplantation is estimated to be cost neutral at 15 years after transplantation.

  6. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration

    Directory of Open Access Journals (Sweden)

    Jyuhn-Huarng Juang

    2015-02-01

    Full Text Available The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histology with cell tracing to reveal the participation of Schwann cells and pericytes in mouse islet transplantation. Longitudinal studies of the grafts under the kidney capsule identify that the donor Schwann cells and pericytes re-associate with the engrafted islets at the peri-graft and perivascular domains, respectively, indicating their adaptability in transplantation. Based on the morphological proximity and cellular reactivity, we propose that the new islet microenvironment should include the peri-graft Schwann cell sheath and perivascular pericytes as an integral part of the new tissue.

  7. Survival of Free and Encapsulated Human and Rat Islet Xenografts Transplanted into the Mouse Bone Marrow

    Science.gov (United States)

    Meier, Raphael P. H.; Seebach, Jörg D.; Morel, Philippe; Mahou, Redouan; Borot, Sophie; Giovannoni, Laurianne; Parnaud, Geraldine; Montanari, Elisa; Bosco, Domenico; Wandrey, Christine; Berney, Thierry; Bühler, Leo H.; Muller, Yannick D.

    2014-01-01

    Bone marrow was recently proposed as an alternative and potentially immune-privileged site for pancreatic islet transplantation. The aim of the present study was to assess the survival and rejection mechanisms of free and encapsulated xenogeneic islets transplanted into the medullary cavity of the femur, or under the kidney capsule of streptozotocin-induced diabetic C57BL/6 mice. The median survival of free rat islets transplanted into the bone marrow or under the kidney capsule was 9 and 14 days, respectively, whereas that of free human islets was shorter, 7 days (bone marrow) and 10 days (kidney capsule). Infiltrating CD8+ T cells and redistributed CD4+ T cells, and macrophages were detected around the transplanted islets in bone sections. Recipient mouse splenocytes proliferated in response to donor rat stimulator cells. One month after transplantation under both kidney capsule or into bone marrow, encapsulated rat islets had induced a similar degree of fibrotic reaction and still contained insulin positive cells. In conclusion, we successfully established a small animal model for xenogeneic islet transplantation into the bone marrow. The rejection of xenogeneic islets was associated with local and systemic T cell responses and macrophage recruitment. Although there was no evidence for immune-privilege, the bone marrow may represent a feasible site for encapsulated xenogeneic islet transplantation. PMID:24625569

  8. Survival of free and encapsulated human and rat islet xenografts transplanted into the mouse bone marrow.

    Directory of Open Access Journals (Sweden)

    Raphael P H Meier

    Full Text Available Bone marrow was recently proposed as an alternative and potentially immune-privileged site for pancreatic islet transplantation. The aim of the present study was to assess the survival and rejection mechanisms of free and encapsulated xenogeneic islets transplanted into the medullary cavity of the femur, or under the kidney capsule of streptozotocin-induced diabetic C57BL/6 mice. The median survival of free rat islets transplanted into the bone marrow or under the kidney capsule was 9 and 14 days, respectively, whereas that of free human islets was shorter, 7 days (bone marrow and 10 days (kidney capsule. Infiltrating CD8+ T cells and redistributed CD4+ T cells, and macrophages were detected around the transplanted islets in bone sections. Recipient mouse splenocytes proliferated in response to donor rat stimulator cells. One month after transplantation under both kidney capsule or into bone marrow, encapsulated rat islets had induced a similar degree of fibrotic reaction and still contained insulin positive cells. In conclusion, we successfully established a small animal model for xenogeneic islet transplantation into the bone marrow. The rejection of xenogeneic islets was associated with local and systemic T cell responses and macrophage recruitment. Although there was no evidence for immune-privilege, the bone marrow may represent a feasible site for encapsulated xenogeneic islet transplantation.

  9. A novel redox-active metalloporphyrin reduces reactive oxygen species and inflammatory markers but does not improve marginal mass engraftment in a murine donation after circulatory death islet transplantation model.

    Science.gov (United States)

    Bruni, Antonio; Pepper, Andrew R; Gala-Lopez, Boris; Pawlick, Rena; Abualhassan, Nasser; Crapo, James D; Piganelli, Jon D; Shapiro, A M James

    2016-07-03

    Islet transplantation is a highly effective treatment for stabilizing glycemic control for select patients with type-1 diabetes. Despite improvements to clinical transplantation, single-donor transplant success has been hard to achieve routinely, necessitating increasing demands on viable organ availability. Donation after circulatory death (DCD) may be an alternative option to increase organ availability however, these organs tend to be more compromised. The use of metalloporphyrin anti-inflammatory and antioxidant (MnP) compounds previously demonstrated improved in vivo islet function in preclinical islet transplantation. However, the administration of MnP (BMX-001) in a DCD islet isolation and transplantation model has yet to be established. In this study, murine donors were subjected to a 15-min warm ischemic (WI) period prior to isolation and culture with or without MnP. Subsequent to one-hour culture, islets were assessed for in vitro viability and in vivo function. A 15-minute WI period significantly reduced islet yield, regardless of MnP-treatment relative to yields from standard isolation. MnP-treated islets did not improve islet viability compared to DCD islets alone. MnP-treatment did significantly reduce the presence of extracellular reactive oxygen species (ROS) (p islets (200 islets) transplanted under the renal capsule exhibited similar in vivo outcomes regardless of WI or MnP-treatment. DCD islet grafts harvested 7 d post-transplant exhibited sustained TNF-α and IL-10, while MnP-treated islet-bearing grafts demonstrated reduced IL-10 levels. Taken together, 15-minute WI in murine islet isolation significantly impairs islet yield. DCD islets do indeed demonstrate in vivo function, though MnP therapy was unable to improve viability and engraftment outcomes.

  10. The Spleen Is an Ideal Site for Inducing Transplanted Islet Graft Expansion in Mice.

    Directory of Open Access Journals (Sweden)

    Takeshi Itoh

    Full Text Available Alternative islet transplantation sites have the potential to reduce the marginal number of islets required to ameliorate hyperglycemia in recipients with diabetes. Previously, we reported that T cell leukemia homeobox 1 (Tlx1+ stem cells in the spleen effectively regenerated into insulin-producing cells in the pancreas of non-obese diabetic mice with end-stage disease. Thus, we investigated the spleen as a potential alternative islet transplantation site. Streptozotocin-induced diabetic C57BL/6 mice received syngeneic islets into the portal vein (PV, beneath the kidney capsule (KC, or into the spleen (SP. The marginal number of islets by PV, KC, or SP was 200, 100, and 50, respectively. Some plasma inflammatory cytokine levels in the SP group were significantly lower than those of the PV group after receiving a marginal number of islets, indicating reduced inflammation in the SP group. Insulin contents were increased 280 days after islet transplantation compared with those immediately following transplantation (p<0.05. Additionally, Tlx1-related genes, including Rrm2b and Pla2g2d, were up-regulated, which indicates that islet grafts expanded in the spleen. The spleen is an ideal candidate for an alternative islet transplantation site because of the resulting reduced inflammation and expansion of the islet graft.

  11. Modular tissue engineering for the vascularization of subcutaneously transplanted pancreatic islets.

    Science.gov (United States)

    Vlahos, Alexander E; Cober, Nicholas; Sefton, Michael V

    2017-08-29

    The transplantation of pancreatic islets, following the Edmonton Protocol, is a promising treatment for type I diabetics. However, the need for multiple donors to achieve insulin independence reflects the large loss of islets that occurs when islets are infused into the portal vein. Finding a less hostile transplantation site that is both minimally invasive and able to support a large transplant volume is necessary to advance this approach. Although the s.c. site satisfies both these criteria, the site is poorly vascularized, precluding its utility. To address this problem, we demonstrate that modular tissue engineering results in an s.c. vascularized bed that enables the transplantation of pancreatic islets. In streptozotocin-induced diabetic SCID/beige mice, the injection of 750 rat islet equivalents embedded in endothelialized collagen modules was sufficient to restore and maintain normoglycemia for 21 days; the same number of free islets was unable to affect glucose levels. Furthermore, using CLARITY, we showed that embedded islets became revascularized and integrated with the host's vasculature, a feature not seen in other s.c. Collagen-embedded islets drove a small (albeit not significant) shift toward a proangiogenic CD206 + MHCII - (M2-like) macrophage response, which was a feature of module-associated vascularization. While these results open the potential for using s.c. islet delivery as a treatment option for type I diabetes, the more immediate benefit may be for the exploration of revascularized islet biology.

  12. Islet graft survival and function: concomitant culture and transplantation with vascular endothelial cells in diabetic rats.

    Science.gov (United States)

    Pan, Xiaoming; Xue, Wujun; Li, Yang; Feng, Xinshun; Tian, Xiaohui; Ding, Chenguang

    2011-12-15

    Human islet transplantation is a great potential therapy for type I diabetes. To investigate islet graft survival and function, we recently showed the improved effects after co-culture and co-transplantation with vascular endothelial cells (ECs) in diabetic rats. ECs were isolated, and the viability of isolated islets was assessed in two groups (standard culture group and co-culture group with ECs). Then streptozotocin-induced diabetic rats were divided into four groups before islet transplantation as follows: group A with infusion of islet grafts; group B with combined vascular ECs and islet grafts; groups C and D as controls with single ECs infusion and phosphate-buffered saline injection, respectively. Blood glucose and insulin concentrations were measured daily. Expression of vascular endothelial growth factor was investigated by immunohistochemical staining. The mean microvascular density was also calculated. More than 90% of acridine orange-propidium iodide staining positive islets demonstrated normal morphology while co-cultured with ECs for 7 days. Compared with standard control, insulin release assays showed a significantly higher simulation index in co-culture group except for the first day (Ptransplantation, there was a significant difference in concentrations of blood glucose and insulin among these groups after 3 days (Pislet group (P=0.04). Co-culture with ECs in vitro could improve the survival and function of isolated rat islet, and co-transplantation of islets with ECs could effectively prolong the islet graft survival in diabetic rats.

  13. Utilization of organs from donors after circulatory death for vascularized pancreas and islet of Langerhans transplantation: recommendations from an expert group.

    Science.gov (United States)

    Berney, Thierry; Boffa, Catherine; Augustine, Titus; Badet, Lionel; de Koning, Eelco; Pratschke, Johann; Socci, Carlo; Friend, Peter

    2016-07-01

    Donation after circulatory death (DCD) donors are increasingly being used as a source of pancreas allografts for vascularized organ and islet transplantation. We provide practice guidelines aiming to increase DCD pancreas utilization. We review risk assessment and donor selection criteria. We report suggested factors in donor and recipient clinical management and provide an overview of the activities and outcomes of vascularized pancreas and islet transplantation. © 2015 Steunstichting ESOT.

  14. Transplantation of micro- and macroencapsulated piglet islets into mice and monkeys.

    Science.gov (United States)

    Elliott, R B; Escobar, L; Calafiore, R; Basta, G; Garkavenko, O; Vasconcellos, A; Bambra, C

    2005-01-01

    Neonatal porcine islets within alginate microcapsules transplanted intraperitoneally (IP) or within semi-permeable macrocapsules (TheraCyte) and transplanted subcutaneously (SC) survive and reverse diabetes for up to 16 weeks in diabetic autoimmune nonobese diabetic (NOD) mice. The islets in microcapsules transplanted IP into nondiabetic cynomolgus monkeys survived for 8 weeks. Similar results were shown with islets transplanted in TheraCytes. Neither species showed adverse effects or evidence of infection with porcine endogenous retroviruses or other endemic pig viruses. Proof of principle is illustrated for successful xenotransplantation in humans.

  15. A Metabolomic Approach (1H HRMAS NMR Spectroscopy) Supported by Histology to Study Early Post-transplantation Responses in Islet-transplanted Livers

    OpenAIRE

    Vivot, Kevin; Benahmed, Malika A.; Seyfritz, Elodie; Bietiger, William; Elbayed, Karim; Ruhland, Elisa; Langlois, Allan; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Gies, Jean-Pierre; Namer, Izzie-Jacques; Sigrist, S?verine; Reix, Nathalie

    2016-01-01

    Intrahepatic transplantation of islets requires a lot of islets because more than 50% of the graft is lost during the 24 hours following transplantation. We analyzed, in a rat model, early post-transplantation inflammation using systemic inflammatory markers, or directly in islet-transplanted livers by immunohistochemistry. 1H HRMAS NMR was employed to investigate metabolic responses associated with the transplantation. Inflammatory markers (Interleukin-6, ?2-macroglobulin) are not suitable t...

  16. Lung-Derived Microscaffolds Facilitate Diabetes Reversal after Mouse and Human Intraperitoneal Islet Transplantation.

    Science.gov (United States)

    Abualhassan, Nasser; Sapozhnikov, Lena; Pawlick, Rena L; Kahana, Meygal; Pepper, Andrew R; Bruni, Antonio; Gala-Lopez, Boris; Kin, Tatsuya; Mitrani, Eduardo; Shapiro, A M James

    2016-01-01

    There is a need to develop three-dimensional structures that mimic the natural islet tissue microenvironment. Endocrine micro-pancreata (EMPs) made up of acellular organ-derived micro-scaffolds seeded with human islets have been shown to express high levels of key beta-cell specific genes and secrete quantities of insulin per cell similar to freshly isolated human islets in a glucose-regulated manner for more than three months in vitro. The aim of this study was to investigate the capacity of EMPs to restore euglycemia in vivo after transplantation of mouse or human islets in chemically diabetic mice. We proposed that the organ-derived EMPs would restore the extracellular components of the islet microenvironment, generating favorable conditions for islet function and survival. EMPs seeded with 500 mouse islets were implanted intraperitoneally into streptozotocin-induced diabetic mice and reverted diabetes in 67% of mice compared to 13% of controls (p = 0.018, n = 9 per group). Histological analysis of the explanted grafts 60 days post-transplantation stained positive for insulin and exhibited increased vascular density in a collagen-rich background. EMPs were also seeded with human islets and transplanted into the peritoneal cavity of immune-deficient diabetic mice at 250 islet equivalents (IEQ), 500 IEQ and 1000 IEQ. Escalating islet dose increased rates of normoglycemia (50% of the 500 IEQ group and 75% of the 1000 IEQ group, n = 3 per group). Human c-peptide levels were detected 90 days post-transplantation in a dose-response relationship. Herein, we report reversal of diabetes in mice by intraperitoneal transplantation of human islet seeded on EMPs with a human islet dose as low as 500 IEQ.

  17. Inactivation of p27kip1 Promoted Nonspecific Inflammation by Enhancing Macrophage Proliferation in Islet Transplantation.

    Science.gov (United States)

    Li, Yang; Ding, Xiaoming; Fan, Ping; Guo, Jian; Tian, Xiaohui; Feng, Xinshun; Zheng, Jin; Tian, Puxun; Ding, Chenguang; Xue, Wujun

    2016-11-01

    Islet transplantation suffers from low efficiency caused by nonspecific inflammation-induced graft loss after transplantation. This study reports increased islet loss and enhanced inflammatory response in p27-deficient mice (p27-/-) and proposes a possible mechanism. Compared with wild type, p27-/- mice showed more severe functional injury of islet, with increased serum levels of inflammatory cytokines IL-1 and TNF-α, inducing macrophage proliferation. Furthermore, the increased number, proapoptotic proteins, and nuclear factor-kappa b (NF-κB) phosphorylation status of the infiltrating macrophages were accompanied by increased TNF-α mRNA level of islet graft site in p27-/- mice. Moreover, in vitro, we found that macrophages were still activated and cocultured with islet and promoted islet loss even blocking the direct effect of TNF-α on islets. Malondialdehyde (MDA, an end product of lipid peroxidation) in islet and media were increased after cocultured with macrophages. p27 deficiency also increased macrophage proliferation and islet injury. Therefore, p27 inactivation promotes injury islet graft loss via the elevation of proliferation and inflammatory cytokines secretion in infiltrating macrophages which induced nonspecific inflammation independent of TNF-α/nuclear factor-kappa b pathway. This potentially represents a promising therapeutic target in improving islet graft survival.

  18. Intraportal islet oxygenation.

    Science.gov (United States)

    Suszynski, Thomas M; Avgoustiniatos, Efstathios S; Papas, Klearchos K

    2014-05-01

    Islet transplantation (IT) is a promising therapy for the treatment of diabetes. The large number of islets required to achieve insulin independence limit its cost-effectiveness and the number of patients who can be treated. It is believed that >50% of islets are lost in the immediate post-IT period. Poor oxygenation in the early post-IT period is recognized as a possible reason for islet loss and dysfunction but has not been extensively studied. Several key variables affect oxygenation in this setting, including (1) local oxygen partial pressure (pO(2)), (2) islet oxygen consumption, (3) islet size (diameter, D), and (4) presence or absence of thrombosis on the islet surface. We discuss implications of oxygen-limiting conditions on intraportal islet viability and function. Of the 4 key variables, the islet size appears to be the most important determinant of the anoxic and nonfunctional islet volume fractions. Similarly, the effect of thrombus formation on the islet surface may be substantial. At the University of Minnesota, average size distribution data from clinical alloislet preparations (n = 10) indicate that >150-µm D islets account for only ~30% of the total islet number, but >85% of the total islet volume. This suggests that improved oxygen supply to the islets may have a profound impact on islet survivability and function since most of the β-cell volume is within large islets which are most susceptible to oxygen-limiting conditions. The assumption that the liver is a suitable islet transplant site from the standpoint of oxygenation should be reconsidered. © 2014 Diabetes Technology Society.

  19. Improving the use of donor organs in pancreas and islet of Langerhans transplantation

    NARCIS (Netherlands)

    Hilling, Denise Eline

    2012-01-01

    Pancreas transplantation and islet of Langerhans transplantation are potential solutions to treat patients with type 1 diabetes. However, pancreas grafts are scarce and there is a shortage of donor pancreata relative to the number of patients needing a transplant. The aim of this thesis was to

  20. Isolation, transplantation, and functional studies of adult porcine islets of Langerhans

    DEFF Research Database (Denmark)

    Nielsen, Thomas Buschmann; Yderstræde, Knud Bonnet; Beck-Nielsen, Henning

    2002-01-01

    that was only partially increased by additional challenge with arginine. More than 50% of DNA and 90% of the insulin content was lost during a one-week culture period. With some batch-to-batch variation, in 15 of 25 cases, 4,000 to 7,000 porcine islets cured streptozotocin diabetic nude mice within three weeks......Transplantation of islets of Langerhans is a possible treatment for type-I diabetes mellitus. However, there is a shortage of donors for such transplantations and the pig may be an alternative source of donor organs. The aims of the study reported here were to establish a method for adult porcine...... following transplantation. In conclusion, it is possible to isolate viable islets from adult pigs, using a semiautomatic set-up. With batch-to-batch variation, the islets are able to revert diabetes mellitus when transplanted to diabetic nude mice....

  1. Impact of Procedure-Related Complications on Long-term Islet Transplantation Outcome.

    Science.gov (United States)

    Caiazzo, Robert; Vantyghem, Marie-Christine; Raverdi, Violeta; Bonner, Caroline; Gmyr, Valery; Defrance, Frederique; Leroy, Clara; Sergent, Geraldine; Hubert, Thomas; Ernst, Oliver; Noel, Christian; Kerr-Conte, Julie; Pattou, François

    2015-05-01

    Pancreatic islet transplantation offers a promising biotherapy for the treatment of type 1 diabetes, but this procedure has met significant challenges over the years. One such challenge is to address why primary graft function still remains inconsistent after islet transplantation. Several variables have been shown to affect graft function, but the impact of procedure-related complications on primary and long-term graft functions has not yet been explored. Twenty-six patients with established type 1 diabetes were included in this study. Each patient had two to three intraportal islet infusions to obtain 10,000 islet equivalent (IEQ)/kg in body weight, equaling a total of 68 islet infusions. Islet transplantation consisted of three sequential fresh islet infusions within 3 months. Islet infusions were performed surgically or under ultrasound guidance, depending on patient morphology, availability of the radiology suite, and patient medical history. Prospective assessment of adverse events was recorded and graded using "Common Terminology Criteria for adverse events in Trials of Adult Pancreatic Islet Transplantation." There were no deaths or patients dropouts. Early complications occurred in nine of 68 procedures. β score 1 month after the last graft and optimal graft function (β score ≥7) rate were significantly lower in cases of procedure-related complications (P = 0.02, P = 0.03). Procedure-related complications negatively impacted graft function (P = 0.009) and was an independent predictive factor of long-term graft survival (P = 0.033) in multivariate analysis. Complications occurring during radiologic or surgical intraportal islet transplantation significantly impair primary graft function and graft survival regardless of their severity.

  2. Mesenchymal stem cell and derived exosome as small RNA carrier and Immunomodulator to improve islet transplantation.

    Science.gov (United States)

    Wen, Di; Peng, Yang; Liu, Di; Weizmann, Yossi; Mahato, Ram I

    2016-09-28

    Human bone marrow mesenchymal stem cells (hBMSCs) and their exosomes can suppress immune reaction and deliver small RNAs. Thus, they may improve islet transplantation by delivering small RNAs for promoting islet function and inhibiting immune rejection. Here, we proposed an hBMSC and its exosome-based therapy to overcome immune rejection and poor islet function, both of which hinder the success of islet transplantation. We found overexpressed siFas and anti-miR-375 in plasmid encoding shFas and anti-miR-375 transfected hBMSC-derived exosomes, which silenced Fas and miR-375 of human islets and improved their viability and function against inflammatory cytokines. This plasmid transfected hBMSCs downregulated Fas and miR-375 of human islets in a humanized NOD scid gamma (NSG) mouse model, whose immune reaction was inhibited by injecting hBMSC and peripheral blood mononuclear cell (PBMC) co-cultured exosomes. These exosomes suppressed immune reaction by inhibiting PBMC proliferation and enhancing regulatory T cell (Treg) function. Collectively, our studies elucidated the mechanisms of RNA delivery from hBMSCs to human islets and the immunosuppressive effect of hBMSC and peripheral blood mononuclear cell co-cultured exosomes for improving islet transplantation. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Kidney Versus Islet Allograft Survival After Induction of Mixed Chimerism With Combined Donor Bone Marrow Transplantation.

    Science.gov (United States)

    Oura, Tetsu; Ko, Dicken S C; Boskovic, Svjetlan; O'Neil, John J; Chipashvili, Vaja; Koulmanda, Maria; Hotta, Kiyohiko; Kawai, Kento; Nadazdin, Ognjenka; Smith, R Neal; Cosimi, A B; Kawai, Tatsuo

    2016-01-01

    We have previously reported successful induction of transient mixed chimerism and long-term acceptance of renal allografts in MHC mismatched nonhuman primates. In this study, we attempted to extend this tolerance induction approach to islet allografts. A total of eight recipients underwent MHC mismatched combined islet and bone marrow (BM) transplantation after induction of diabetes by streptozotocin. Three recipients were treated after a nonmyeloablative conditioning regimen that included low-dose total body and thymic irradiation, horse Atgam (ATG), six doses of anti-CD154 monoclonal antibody (mAb), and a 1-month course of cyclosporine (CyA) (Islet A). In Islet B, anti-CD8 mAb was administered in place of CyA. In Islet C, two recipients were treated with Islet B, but without ATG. The results were compared with previously reported results of eight cynomolgus monkeys that received combined kidney and BM transplantation (Kidney A) following the same conditioning regimen used in Islet A. The majority of kidney/BM recipients achieved long-term renal allograft survival after induction of transient chimerism. However, prolonged islet survival was not achieved in similarly conditioned islet/BM recipients (Islet A), despite induction of comparable levels of chimerism. In order to rule out islet allograft loss due to CyA toxicity, three recipients were treated with anti-CD8 mAb in place of CyA. Although these recipients developed significantly superior mixed chimerism and more prolonged islet allograft survival (61, 103, and 113 days), islet function was lost soon after the disappearance of chimerism. In Islet C recipients, neither prolonged chimerism nor islet survival was observed (30 and 40 days). Significant improvement of mixed chimerism induction and islet allograft survival were achieved with a CyA-free regimen that included anti-CD8 mAb. However, unlike the kidney allograft, islet allograft tolerance was not induced with transient chimerism. Induction of more

  4. Cross-sensitization between xeno- and allo-antigens on subsequent allogeneic and xenogeneic pancreatic islet transplantation in a murine model.

    Science.gov (United States)

    Kim, Hyun-Je; Byun, Nari; Kwon, Ohsang; Park, Chung-Gyu

    2016-11-18

    The number of patients in need of organ transplantation is continuously on the rise. However, because of organ donor shortage, xenotransplantation has been highlighted as an alternative. Among the various porcine organs and tissues, porcine islets are considered to be the best-matching implantable candidates for clinical application based on recent progress in nonhuman primate pre-clinical studies. Nevertheless, before initiation of clinical trials, it should be confirmed whether the requisite xeno-antigen sensitization would have a deleterious effect on subsequent allo-transplantation or vice versa. Therefore, in the present study, the survival rate of islets grafted in naïve recipients was compared with that in cross-sensitized recipients. Enzyme-linked immunosorbent spot, fluorescence-activated cell sorting, and immunohistochemistry were conducted to assess the cellular and humoral immune responses. The survival days of Balb/c mouse islets transplanted into B6 mice that had been previously sensitized with porcine cells (i.e., xeno-sensitized) showed no significant difference from that of naïve B6 mice. Moreover, the survival days of porcine islets transplanted into allo-antigen (Balb/c)-sensitized B6 recipients was not significantly different from that in naïve B6 mice. Furthermore, our data provide the first demonstration that the cellular xenogeneic immune response (against porcine antigen) measured by an enzyme-linked immunosorbent spot assay is not cross-reactive to the allogeneic immune responses in a murine islet transplantation model. These results suggest that clinical application of islet xenotransplantation is not likely to have a deleterious effect on subsequent allogeneic islet transplantation. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Islet transplantation as safe and efficacious method to restore glycemic control and to avoid severe hypoglycemia after donor organ failure in pancreas transplantation.

    Science.gov (United States)

    Gerber, Philipp A; Hochuli, Michel; Benediktsdottir, Bara D; Zuellig, Richard A; Tschopp, Oliver; Glenck, Michael; de Rougemont, Olivier; Oberkofler, Christian; Spinas, Giatgen A; Lehmann, Roger

    2018-01-01

    The aim of this study was to assess safety and efficacy of islet transplantation after initial pancreas transplantation with subsequent organ failure. Patients undergoing islet transplantation at our institution after pancreas organ failure were compared to a control group of patients with pancreas graft failure, but without islet transplantation and to a group receiving pancreas retransplantation. Ten patients underwent islet transplantation after initial pancreas transplantation failed and were followed for a median of 51 months. The primary end point of HbA1c islet transplantation and in all three patients in the pancreas retransplantation group, but by none of the patients in the group without retransplantation (n = 7). Insulin requirement was reduced by 50% after islet transplantation. Kidney function (eGFR) declined with a rate of -1.0 mL ± 1.2 mL/min/1.73 m 2 per year during follow-up after islet transplantation, which tended to be slower than in the group without retransplantation (P = .07). Islet transplantation after deceased donor pancreas transplant failure is a method that can safely improve glycemic control and reduce the incidence of severe hypoglycemia and thus establish similar glycemic control as after initial pancreas transplantation, despite the need of additional exogenous insulin. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Preclinical evaluation of a 68Ga-labeled biotin analogue for applications in islet transplantation

    International Nuclear Information System (INIS)

    Eriksson, Olof; Carlsson, Fredrik; Blom, Elisabeth; Sundin, Anders; Långström, Bengt; Korsgren, Olle; Velikyan, Irina

    2012-01-01

    Introduction: Islet transplantation is a promising treatment for type 1 diabetes mellitus, but the fate of the cells after intraportal infusion is unclear. It is therefore imperative to develop novel techniques for noninvasive imaging and quantification of events following islet transplantation. Methods: Small islet-like microbeads, avidin-covered agarose resins (AARs), were used as a model system for islet transplantation. Capability for specific [ 68 Ga]Ga-DOTA-(PEG) 2 -biotin uptake and retention for either AARs or human islets conjugated with avidin by means of a heparin scaffold was studied in vitro. Biodistribution of the novel positron emission tomography (PET) tracer [ 68 Ga]Ga-DOTA-(PEG) 2 -biotin was evaluated in mice treated by intraportal transplantation of AARs by μPET/computed tomography and ex vivo organ distribution and compared with control mice. Results: AARs had high capability to bind [ 68 Ga]Ga-DOTA-(PEG) 2 -biotin, close to 50% of administrated tracer/μl in vitro (>0.25 MBq/μl). Avidin-tagged human islets could bind on average 2.2% of administered tracer/μl. Specificity (>90%) and retention (>90% after 1 h) were high for both AARs and avidin-tagged islets. Hepatic tracer uptake and retention were increased in mice transplanted with AARs [standardized uptake value (SUV)=2.6] compared to the untreated group (SUV=1.4). In vivo uptake of tracer to AARs was blocked by preadministration of unlabeled biotin. Conclusions: Avidin-tagged islet-like objects can be tracked in hepatic volume after intraportal transplantation by using [ 68 Ga]Ga-DOTA-(PEG) 2 -biotin and PET.

  7. Single-donor islet transplantation in type 1 diabetes: patient selection and special considerations

    Directory of Open Access Journals (Sweden)

    Tatum JA

    2017-02-01

    Full Text Available Jacob A Tatum,* Max O Meneveau,* Kenneth L Brayman Department of Surgery, Division of Transplantation, The University of Virginia Health System, Charlottesville, VA, USA *These authors contributed equally to this work. Abstract: Type 1 diabetes mellitus is an autoimmune disorder of the endocrine pancreas that currently affects millions of people in the United States. Although the disease can be managed with exogenous insulin administration, the ultimate cure for the condition lies in restoring a patient’s ability to produce their own insulin. Islet cell allotransplantation provides a means of endogenous insulin production. Though far from perfected, islet transplants are now a proven treatment for type 1 diabetics. However, proper patient selection is critical for achieving optimal outcomes. Given the shortage of transplantable organs, selecting appropriate candidates for whom the procedure will be of greatest benefit is essential. Although many of those who receive islets do not retain insulin independence, grafts do play a significant role in preventing hypoglycemic episodes that can be quite detrimental to quality of life and potentially fatal. Additionally, islet transplant requires lifelong immunosuppression. Antibodies, both preformed and following islet infusion, may play important roles in graft outcomes. Finally, no procedure is without inherent risk and islet transfusions can have serious consequences for recipients’ livers in the form of both vascular and metabolic complications. Therefore, patient-specific factors that should be taken into account before islet transplantation include aims of therapy, sensitization, and potential increased risk for hepatic and portal-venous sequelae. Keywords: islet transplantation, diabetes mellitus type 1, brittle diabetes, single donor, patient

  8. Physiologic Doses of Bilirubin Contribute to Tolerance of Islet Transplants by Suppressing the Innate Immune Response.

    Science.gov (United States)

    Adin, Christopher A; VanGundy, Zachary C; Papenfuss, Tracey L; Xu, Feng; Ghanem, Mostafa; Lakey, Jonathan; Hadley, Gregg A

    2017-01-24

    Bilirubin has been recognized as a powerful cytoprotectant when used at physiologic doses and was recently shown to have immunomodulatory effects in islet allograft transplantation, conveying donor-specific tolerance in a murine model. We hypothesized that bilirubin, an antioxidant, acts to suppress the innate immune response to islet allografts through two mechanisms: 1) by suppressing graft release of damage-associated molecular patterns (DAMPs) and inflammatory cytokines, and 2) by producing a tolerogenic phenotype in antigen-presenting cells. Bilirubin was administered intraperitoneally before pancreatic procurement or was added to culture media after islet isolation in AJ mice. Islets were exposed to transplant-associated nutrient deprivation and hypoxia. Bilirubin significantly decreased islet cell death after isolation and hypoxic stress. Bilirubin supplementation of islet media also decreased the release of DAMPs (HMGB1), inflammatory cytokines (IL-1β and IL-6), and chemokines (MCP-1). Cytoprotection was mediated by the antioxidant effects of bilirubin. Treatment of macrophages with bilirubin induced a regulatory phenotype, with increased expression of PD-L1. Coculture of these macrophages with splenocytes led to expansion of Foxp3+ Tregs. In conclusion, exogenous bilirubin supplementation showed cytoprotective and antioxidant effects in a relevant model of islet isolation and hypoxic stress. Suppression of DAMP release, alterations in cytokine profiles, and tolerogenic effects on macrophages suggest that the use of this natural antioxidant may provide a method of preconditioning to improve outcomes after allograft transplantation.

  9. Long-Term Follow-Up of the Edmonton Protocol of Islet Transplantation in the United States.

    Science.gov (United States)

    Brennan, D C; Kopetskie, H A; Sayre, P H; Alejandro, R; Cagliero, E; Shapiro, A M J; Goldstein, J S; DesMarais, M R; Booher, S; Bianchine, P J

    2016-02-01

    We report the long-term follow-up of the efficacy and safety of islet transplantation in seven type 1 diabetic subjects from the United States enrolled in the multicenter international Edmonton Protocol who had persistent islet function after completion of the Edmonton Protocol. Subjects were followed up to 12 years with serial testing for sustained islet allograft function as measured by C-peptide. All seven subjects demonstrated continued islet function longer than a decade from the time of first islet transplantation. One subject remained insulin independent without the need for diabetic medications or supplemental transplants. One subject who was insulin-independent for over 8 years experienced graft failure 10.9 years after the first islet transplant. The remaining six subjects demonstrated continued islet function upon trial completion, although three had received a supplemental islet transplant each. At trial completion, five subjects were receiving insulin and two remained insulin independent, although one was treated with liraglutide. The median hemoglobin A1c was 6.3% (45 mmol/mol). All subjects experienced progressive decline in the C-peptide/glucose ratio. No patients experienced severe hypoglycemia, opportunistic infection, or lymphoma. Thus, although the rate and duration of insulin independence was low, the Edmonton Protocol was safe in the long term. Alternative approaches to islet transplantation are under investigation. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  10. Design of a vascularized synthetic poly(ethylene glycol) macroencapsulation device for islet transplantation.

    Science.gov (United States)

    Weaver, Jessica D; Headen, Devon M; Hunckler, Michael D; Coronel, Maria M; Stabler, Cherie L; García, Andrés J

    2018-07-01

    The use of immunoisolating macrodevices in islet transplantation confers the benefit of safety and translatability by containing transplanted cells within a single retrievable device. To date, there has been limited development and characterization of synthetic poly(ethylene glycol) (PEG)-based hydrogel macrodevices for islet encapsulation and transplantation. Herein, we describe a two-component synthetic PEG hydrogel macrodevice system, designed for islet delivery to an extrahepatic islet transplant site, consisting of a hydrogel core cross-linked with a non-degradable PEG dithiol and a vasculogenic outer layer cross-linked with a proteolytically sensitive peptide to promote degradation and enhance localized vascularization. Synthetic PEG macrodevices exhibited equivalent passive molecular transport to traditional microencapsulation materials (e.g., alginate) and long-term stability in the presence of proteases in vitro and in vivo, out to 14 weeks in rats. Encapsulated islets demonstrated high viability within the device in vitro and the incorporation of RGD adhesive peptides within the islet encapsulating PEG hydrogel improved insulin responsiveness to a glucose challenge. In vivo, the implementation of a vasculogenic, degradable hydrogel layer at the outer interface of the macrodevice enhanced vascular density within the rat omentum transplant site, resulting in improved encapsulated islet viability in a syngeneic diabetic rat model. These results highlight the benefits of the facile PEG platform to provide controlled presentation of islet-supportive ligands, as well as degradable interfaces for the promotion of engraftment and overall graft efficacy. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Loss of end-differentiated β-cell phenotype following pancreatic islet transplantation.

    Science.gov (United States)

    Anderson, S J; White, M G; Armour, S L; Maheshwari, R; Tiniakos, D; Muller, Y D; Berishvili, E; Berney, T; Shaw, J A M

    2018-03-01

    Replacement of pancreatic β-cells through deceased donor islet transplantation is a proven therapy for preventing recurrent life-threatening hypoglycemia in type 1 diabetes. Although near-normal glucose levels and insulin independence can be maintained for many years following successful islet transplantation, restoration of normal functional β-cell mass has remained elusive. It has recently been proposed that dedifferentiation/plasticity towards other endocrine phenotypes may play an important role in stress-induced β-cell dysfunction in type 2 diabetes. Here we report loss of end-differentiated β-cell phenotype in 2 intraportal islet allotransplant recipients. Despite excellent graft function and sustained insulin independence, all examined insulin-positive cells had lost expression of the end-differentiation marker, urocortin-3, or appeared to co-express the α-cell marker, glucagon. In contrast, no insulin + /urocortin-3 - cells were seen in nondiabetic deceased donor control pancreatic islets. Loss of end-differentiated phenotype may facilitate β-cell survival during the stresses associated with islet isolation and culture, in addition to sustained hypoxia following engraftment. As further refinements in islet isolation and culture are made in parallel with exploration of alternative β-cell sources, graft sites, and ultimately fully vascularized bioengineered insulin-secreting microtissues, differentiation status immunostaining provides a novel tool to assess whether fully mature β-cell phenotype has been maintained. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  12. Altered Expression of Somatostatin Receptors in Pancreatic Islets from NOD Mice Cultured at Different Glucose Concentrations In Vitro and in Islets Transplanted to Diabetic NOD Mice In Vivo

    Directory of Open Access Journals (Sweden)

    Eva Ludvigsen

    2011-01-01

    Full Text Available Somatostatin acts via five receptors (sst1-5. We investigated if the changes in pancreatic islet sst expression in diabetic NOD mice compared to normoglycemic mice are a consequence of hyperglycemia or the ongoing immune reaction in the pancreas. Pancreatic islets were isolated from NOD mice precultured for 5 days and further cultured for 3 days at high or low glucose before examined. Islets were also isolated from NOD mice and transplanted to normal or diabetic mice in a number not sufficient to cure hyperglycemia. After three days, the transplants were removed and stained for sst1-5 and islet hormones. Overall, changes in sst islet cell expression were more common in islets cultured in high glucose concentration in vitro as compared to the islet transplantation in vivo to diabetic mice. The beta and PP cells exhibited more frequent changes in sst expression, while the alpha and delta cells were relatively unaffected by the high glucose condition. Our findings suggest that the glucose level may alter sst expressed in islets cells; however, immune mechanisms may counteract such changes in islet sst expression.

  13. Engraftment Site and Effectiveness of the Pan-Caspase Inhibitor F573 to Improve Engraftment in Mouse and Human Islet Transplantation in Mice.

    Science.gov (United States)

    Pepper, Andrew R; Bruni, Antonio; Pawlick, Rena; Wink, John; Rafiei, Yasmin; Gala-Lopez, Boris; Bral, Mariusz; Abualhassan, Nasser; Kin, Tatsuya; Shapiro, A M James

    2017-10-01

    Islet transplantation is an effective therapy in type 1 diabetes and recalcitrant hypoglycemia. However, there is an ongoing need to circumvent islet loss posttransplant. We explore herein the potential of the pan-caspase inhibitor F573 to mitigate early apoptosis-mediated islet death within portal and extrahepatic portal sites in mice. Mouse or human islets were cultured in standard media ±100 μM F573 and subsequently assessed for viability and apoptosis via terminal deoxynucleotidyl transferase dUTP nick end labeling staining and caspase-3 activation. Diabetic mice were transplanted with syngeneic islets placed under the kidney capsule (KC) or into the subcutaneous deviceless (DL) site at a marginal islet dose (150 islets), or into the portal vein (PV) at a full dose (500 islets). Human islets were transplanted under the KC of diabetic immunodeficient mice at a marginal dose (500 islet equivalents). Islets were cultured in the presence of F573, and F573 was administered subcutaneously on days 0 to 5 posttransplant. Control mice were transplanted with nontreated islets and were injected with saline. Graft function was measured by nonfasting blood glucose and glucose tolerance testing. F573 markedly reduced human and mouse islet apoptosis after in vitro culture (P islet function when transplanted under the KC (P islet marginal KC transplants. Conversely, F573 significantly improved mouse islet engraftment in the PV and DL site (P islet apoptosis and improves engraftment most effectively in the portal and DL subcutaneous sites.

  14. The role of interventional radiology and imaging in pancreatic islet cell transplantation

    International Nuclear Information System (INIS)

    Dixon, S.; Tapping, C.R.; Walker, J.N.; Bratby, M.; Anthony, S.; Boardman, P.; Phillips-Hughes, J.; Uberoi, R.

    2012-01-01

    Pancreatic islet cell transplantation (PICT) is a novel treatment for patients with insulin-dependent diabetes who have inadequate glycaemic control or hypoglycaemic unawareness, and who suffer from the microvascular/macrovascular complications of diabetes despite aggressive medical management. Islet transplantation primarily aims to improve the quality of life for type 1 diabetic patients by achieving insulin independence, preventing hypoglycaemic episodes, and reversing hypoglycaemic unawareness. The islet cells for transplantation are extracted and purified from the pancreas of brain-stem dead, heart-beating donors. They are infused into the recipient's portal vein, where they engraft into the liver to release insulin in order to restore euglycaemia. Initial strategies using surgical access to the portal vein have been superseded by percutaneous access using interventional radiology techniques, which are relatively straightforward to perform. It is important to be vigilant during the procedure in order to prevent major complications, such as haemorrhage, which can be potentially life-threatening. In this article we review the history of islet cell transplantation, present an illustrated review of our experience with islet cell transplantation by describing the role of imaging and interventional radiology, and discuss current research into imaging techniques for monitoring graft function.

  15. Factors Influencing Quantification of in Vivo Bioluminescence Imaging: Application to Assessment of Pancreatic Islet Transplants

    Directory of Open Access Journals (Sweden)

    John Virostko

    2004-10-01

    Full Text Available The aim of this study is to determine and characterize factors influencing in vivo bioluminescence imaging (BLI and apply them to the specific application of imaging transplanted pancreatic islets. Noninvasive quantitative assessment of transplanted pancreatic islets poses a formidable challenge. Murine pancreatic islets expressing firefly luciferase were transplanted under the renal capsule or into the portal vein of nonobese diabetic–severe combined immunodeficiency mice and the bioluminescence was quantified with a cooled charge coupled device camera and digital photon image analysis. The important, but often neglected, effects of wound healing, mouse positioning, and transplantation site on bioluminescence measurements were investigated by imaging a constant emission, isotropic light-emitting bead (λ = 600 implanted at the renal or hepatic site. The renal beads emitted nearly four times more light than hepatic beads with a smaller spot size, indicating that light absorption and scatter are greatly influenced by the transplant site and must be accounted for in BLI measurements. Detected luminescence decreased with increasing angle between the mouse surface normal and optical axis. By defining imaging parameters such as postsurgical effects, animal positioning, and light attenuation as a function of transplant site, this study develops BLI as a useful imaging modality for quantitative assessment of islets post-transplantation.

  16. Effect of total lymphoid irradiation (TLI) and donor bone marrow (BM) on islet transplantation in baboons

    International Nuclear Information System (INIS)

    Nash, J.R.; Smit, J.A.; Myburgh, M.A.; Bell, P.R.F.

    1981-01-01

    The susceptibility of isolated islet allografts to rejection and the limited success of established immunosuppressive technique in influencing it is well known. However, the recent demonstration of the efficacy of TLI and BM in the induction of transplantation tolerance has been a major advance. In this study, we investigated the efficacy of similar irradiation schedules on the prolongation of islet allograft survival in the same animal model

  17. Automated digital image analysis of islet cell mass using Nikon's inverted eclipse Ti microscope and software to improve engraftment may help to advance the therapeutic efficacy and accessibility of islet transplantation across centers.

    Science.gov (United States)

    Gmyr, Valery; Bonner, Caroline; Lukowiak, Bruno; Pawlowski, Valerie; Dellaleau, Nathalie; Belaich, Sandrine; Aluka, Isanga; Moermann, Ericka; Thevenet, Julien; Ezzouaoui, Rimed; Queniat, Gurvan; Pattou, Francois; Kerr-Conte, Julie

    2015-01-01

    Reliable assessment of islet viability, mass, and purity must be met prior to transplanting an islet preparation into patients with type 1 diabetes. The standard method for quantifying human islet preparations is by direct microscopic analysis of dithizone-stained islet samples, but this technique may be susceptible to inter-/intraobserver variability, which may induce false positive/negative islet counts. Here we describe a simple, reliable, automated digital image analysis (ADIA) technique for accurately quantifying islets into total islet number, islet equivalent number (IEQ), and islet purity before islet transplantation. Islets were isolated and purified from n = 42 human pancreata according to the automated method of Ricordi et al. For each preparation, three islet samples were stained with dithizone and expressed as IEQ number. Islets were analyzed manually by microscopy or automatically quantified using Nikon's inverted Eclipse Ti microscope with built-in NIS-Elements Advanced Research (AR) software. The AIDA method significantly enhanced the number of islet preparations eligible for engraftment compared to the standard manual method (p image analysis utilizing the Nikon Instruments software is an unbiased, simple, and reliable teaching tool to comprehensively assess the individual size of each islet cell preparation prior to transplantation. Implementation of this technology to improve engraftment may help to advance the therapeutic efficacy and accessibility of islet transplantation across centers.

  18. INSULIN-SECRETION BY RAT ISLET ISOGRAFTS OF A DEFINED ENDOCRINE VOLUME AFTER TRANSPLANTATION TO 3 DIFFERENT SITES

    NARCIS (Netherlands)

    VANSUYLICHEM, PTR; STRUBBE, JH; HOUWING, H; WOLTERS, GHJ; VANSCHILFGAARDE, R

    1992-01-01

    We have analysed the graft function of rat islet isografts of identical and well-defined endocrine volumes after transplantation to three different sites (kidney, liver and spleen). Graft endocrine mass was determined by measuring the total islet volume prior to transplantation and was chosen to be

  19. Insulin secretion by rat islet isografts of a defined endocrine volume after transplantation to three different sites

    NARCIS (Netherlands)

    Suylichem, P.T.R. van; Strubbe, J.H.; Houwing, H.; Wolters, G.H.J.; Schilfgaarde, R. van

    1992-01-01

    We have analysed the graft function of rat islet isografts of identical and well-defined endocrine volumes after transplantation to three different sites (kidney, liver and spleen). Graft endocrine mass was determined by measuring the total islet volume prior to transplantation and was chosen to be

  20. Preimplantation of an immunoprotective device can lower the curative dose of islets to that of free islet transplantation: studies in a rodent model.

    Science.gov (United States)

    Sörenby, Anne K; Kumagai-Braesch, Makiko; Sharma, Amit; Hultenby, Kjell R; Wernerson, Annika M; Tibell, Annika B

    2008-07-27

    Islet graft survival inside macroencapsulation devices is suboptimal. We hypothesized that induction of neovascularization by preimplantation of devices would improve the physiological conditions, thereby lowering the number of islets required for cure. Several rat islets were transplanted to TheraCyte immunoprotective devices implanted subcutaneously in diabetic athymic mice. Cure rates in the groups with preimplanted devices were significantly better than in those with freshly implanted devices (375 islets: 8/8 vs. 1/6, P=0.003; 125 islets: 6/6 vs. 0/7, P=0.001). Morphometric evaluations of the 125 islet groups showed higher fractional and absolute volumes of endocrine tissue in the group with preimplanted devices (P<0.001 and P=0.035, respectively). In the following dose titration study, using preimplanted devices, as low as 50 islets cured diabetic mice (100% cure, n=6). We conclude that preimplantation significantly lowers the curative dose of macroencapsulated islets to levels resembling those of free islets transplanted under the renal capsule.

  1. Progression of nephropathy after islet of langerhans transplantation in alloxan-induced diabetic rats

    Directory of Open Access Journals (Sweden)

    César Tadeu Spadella

    1997-03-01

    Full Text Available We studied the effects of islet of Langerhans transplantation (IT on the kidney lesions of rats with alloxan-induced diabetes. Forty-five inbred male Lewis rats were randomly assigned to 3 experimental groups: group Gl included 15 non-diabetic control rats (NC, group GIT included 15 alloxan-induced diabetic rats (DC, and group III included 15 alloxan-induced diabetic rats that received pancreatic islet transplantation prepared by nonenzymatic method from normal donor Lewis rats and injected into the portal vein (IT. Each group was further divided into 3 subgroups of 5 rats which were sacrificed at 1, 3, and 6 months of follow-up, respectively. Clinical and laboratorial parameters were recorded in the mentioned periods in the 3 experimental groups. For histology, the kidneys of all rats of each subgroup were studied and 50 glomeruli and 50 tubules of each kidney were analyzed using light microscopy by two different investigators in a double blind study. The results showed progressive glomerular basement membrane thickening (GBMT, mesangial enlargement (ME, and Bowman's capsule thickening (BCT in the 3 experimental groups throughout the follow-up. These alterations were significantly more severe in DC rats at 6 months when compared to NC rats (p < 0.01. However, the degree of GBMT, ME, and BCT observed in DC rats was not statistically different from IT rats at 1, 3, and 6 months. In addition, Armanni-Ebstein lesions of the tubules (AE and tubular lumen protein (PRO observed in DC rats were also observed in IT rats all over the study. These lesions were never present in NC rats. We conclude that IT did not prevent progression of kidney lesions in alloxan-induced diabetic rats within 6 months after transplantation.

  2. Stem Cells as a Tool to Improve Outcomes of Islet Transplantation

    Directory of Open Access Journals (Sweden)

    Emily Sims

    2012-01-01

    Full Text Available The publication of the promising results of the Edmonton protocol in 2000 generated optimism for islet transplantation as a potential cure for Type 1 Diabetes Mellitus. Unfortunately, follow-up data revealed that less than 10% of patients achieved long-term insulin independence. More recent data from other large trials like the Collaborative Islet Transplant Registry show incremental improvement with 44% of islet transplant recipients maintaining insulin independence at three years of follow-up. Multiple underlying issues have been identified that contribute to islet graft failure, and newer research has attempted to address these problems. Stem cells have been utilized not only as a functional replacement for β cells, but also as companion or supportive cells to address a variety of different obstacles that prevent ideal graft viability and function. In this paper, we outline the manners in which stem cells have been applied to address barriers to the achievement of long-term insulin independence following islet transplantation.

  3. A Metabolomic Approach (1H HRMAS NMR Spectroscopy) Supported by Histology to Study Early Post-transplantation Responses in Islet-transplanted Livers.

    Science.gov (United States)

    Vivot, Kevin; Benahmed, Malika A; Seyfritz, Elodie; Bietiger, William; Elbayed, Karim; Ruhland, Elisa; Langlois, Allan; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Gies, Jean-Pierre; Namer, Izzie-Jacques; Sigrist, Séverine; Reix, Nathalie

    2016-01-01

    Intrahepatic transplantation of islets requires a lot of islets because more than 50% of the graft is lost during the 24 hours following transplantation. We analyzed, in a rat model, early post-transplantation inflammation using systemic inflammatory markers, or directly in islet-transplanted livers by immunohistochemistry. 1 H HRMAS NMR was employed to investigate metabolic responses associated with the transplantation. Inflammatory markers (Interleukin-6, α2-macroglobulin) are not suitable to follow islet reactions as they are not islet specific. To study islet specific inflammatory events, immunohistochemistry was performed on sections of islet transplanted livers for thrombin (indicator of the instant blood-mediated inflammatory reaction (IBMIR)) and granulocytes and macrophages. We observed a specific correlation between IBMIR and granulocyte and macrophage infiltration after 12 h. In parallel, we identified a metabolic response associated with transplantation: after 12 h, glucose, alanine, aspartate, glutamate and glutathione were significantly increased. An increase of glucose is a marker of tissue degradation, and could be explained by immune cell infiltration. Alanine, aspartate and glutamate are inter-connected in a common metabolic pathway known to be activated during hypoxia. An increase of glutathione revealed the presence of antioxidant protection. In this study, IBMIR visualization combined with 1 H HRMAS NMR facilitated the characterization of cellular and molecular pathways recruited following islet transplantation.

  4. A Metabolomic Approach (1H HRMAS NMR Spectroscopy) Supported by Histology to Study Early Post-transplantation Responses in Islet-transplanted Livers

    Science.gov (United States)

    Vivot, Kevin; Benahmed, Malika A.; Seyfritz, Elodie; Bietiger, William; Elbayed, Karim; Ruhland, Elisa; Langlois, Allan; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Gies, Jean-Pierre; Namer, Izzie-Jacques; Sigrist, Séverine; Reix, Nathalie

    2016-01-01

    Intrahepatic transplantation of islets requires a lot of islets because more than 50% of the graft is lost during the 24 hours following transplantation. We analyzed, in a rat model, early post-transplantation inflammation using systemic inflammatory markers, or directly in islet-transplanted livers by immunohistochemistry. 1H HRMAS NMR was employed to investigate metabolic responses associated with the transplantation. Inflammatory markers (Interleukin-6, α2-macroglobulin) are not suitable to follow islet reactions as they are not islet specific. To study islet specific inflammatory events, immunohistochemistry was performed on sections of islet transplanted livers for thrombin (indicator of the instant blood-mediated inflammatory reaction (IBMIR)) and granulocytes and macrophages. We observed a specific correlation between IBMIR and granulocyte and macrophage infiltration after 12 h. In parallel, we identified a metabolic response associated with transplantation: after 12 h, glucose, alanine, aspartate, glutamate and glutathione were significantly increased. An increase of glucose is a marker of tissue degradation, and could be explained by immune cell infiltration. Alanine, aspartate and glutamate are inter-connected in a common metabolic pathway known to be activated during hypoxia. An increase of glutathione revealed the presence of antioxidant protection. In this study, IBMIR visualization combined with 1H HRMAS NMR facilitated the characterization of cellular and molecular pathways recruited following islet transplantation. PMID:27766032

  5. Feasibility of baculovirus-mediated reporter gene delivery for efficient monitoring of islet transplantation in vivo

    International Nuclear Information System (INIS)

    Liu, Shuai; Pan, Yu; Lv, Jing; Wu, Haifei; Tian, Jingyan; Zhang, Yifan

    2014-01-01

    Objective: The objective of this study was to explore the feasibility of baculovirus vector-mediated sodium iodide symporter (NIS) gene delivery to monitor islet transplantation. Methods: Baculovirus vectors expressing green fluorescent protein (GFP) or NIS (Bac-GFP and Bac-NIS) were established using the Bac-to-Bac baculovirus expression system. The GFP expression of Bac-GFP-infected rat islets was observed in vitro by fluorescence microscopy. Iodine uptake and inhibition of iodine uptake by NaClO 4 in Bac-NIS-infected islets were dynamically monitored in vitro. Bac-GFP- or Bac-NIS-infected islets were implanted into the left axillary cavity of NOD-SCID mice, and fluorescence imaging and 125 I NanoSPECT/CT imaging were subsequently performed in vivo. Results: Bac-GFP efficiently infected rat islets (over 95% infected at MOI = 40), and the expression of GFP lasted approximately two weeks. NaClO 4 could inhibit iodine uptake by Bac-NIS-infected islets. In vivo imaging revealed that the fluorescence intensity of the transplant sites in Bac-GFP-infected groups was significantly higher than in the non-infected group. Grafts could be clearly observed by 125 I NanoSPECT/CT imaging for up to 8 h. Conclusion: Baculovirus vectors are powerful vehicles for studying rat islets in gene delivery. It is feasible to use a baculovirus vector to delivery an NIS gene for non-invasive monitoring transplanted islets in vivo by the expression of the target gene

  6. Engraftment versus immunosuppression: cost-benefit analysis of immunosuppression after intrahepatic murine islet transplantation.

    Science.gov (United States)

    Marzorati, Simona; Melzi, Raffaella; Citro, Antonio; Cantarelli, Elisa; Mercalli, Alessia; Scavini, Marina; Piemonti, Lorenzo

    2014-05-27

    Immunosuppression (IS) in islet transplantation (Tx) is a double-edged sword: it prevents immunoreaction but has the potential to impair islet engraftment. The aim of this study was to identify in murine animal models the IS platform with the best balance between these two opposite effects. To study the impact of IS on islet engraftment diabetic C57BL/6 mice were transplanted with 350 syngeneic islets through the portal vein and treated once-daily with either rapamycin (RAPA; 0.1-0.5-1 mg/kg ip), tacrolimus (FK506; 0.1-0.5-1 mg/kg ip), mycophenolate mofetil (MMF; 60-120-300 mg/kg oral) or vehicle for 14 days. Islet function was evaluated by measuring not-fasting glycemia and by performing an IVGTT on days 15 and 30 post-Tx. RAPA ≥0.5 mg/Kg, FK506 ≥0.5 mg/Kg, and MMF ≥120 mg/kg had detrimental effects on islet engraftment but not on the function of islets already engrafted in the liver. The effect on engraftment was irreversible and persisted even after IS withdrawal. The lower dose of IS that did not affect engraftment was tested for preventing rejection in the full mismatch allogeneic Tx BALB/c to C57BL/6 model. RAPA and/or FK506 were inefficient in preventing rejection, even when anti-IL2R mAb was added to the IS regimen. On the other hand, MMF alone or in association with FK506 significantly prolonged the time to islet rejection. IS showed profound dose-dependent deleterious effects on islet cell engraftment. The MMF/FK506 combination proved the best balance with less toxicity at the time of engraftment and more efficacy in controlling graft rejection.

  7. Advances in pancreatic islet transplantation for the treatment of diabetes%胰岛移植治疗糖尿病的现状和进展

    Institute of Scientific and Technical Information of China (English)

    彭丹凤; 贾伟平

    2012-01-01

    胰岛移植是治疗糖尿病尤其是1型糖尿病的一种简单有效的方法,相较与胰腺移植,它较为简单和方便,但存在组织来源匮乏和免疫移植排斥等障碍.新的胰岛分离纯化方法提高了供移植的胰岛的纯度和活性.成体干细胞研究、异种移植研究,有望解决移植的供源问题.Edmonton方案在胰岛移植的临床应用中具有里程碑意义.新型的免疫抑制剂和免疫诱导剂的研究可以提高临床胰岛移植的成功率.%Objective Pancreatic islet transplantation is effective in treating diabetes, especially in type 1 diabetes. It can provide diabetes management with good glycemic control and insulin independence. Compared to pancreas transplantation, islet transplantation is technically much simplier and safer. However, currently its clinical use is highly restricted by a series of influence factors, including lack of sufficient donor organs and the side effects of immunosuppressive therapy. With recent advances in methods of islet isolation and purification, we can get better donor organs. Deriving islet cells from other sources such as pigs, human pancreatic duct cells, fetal pancreatic stem cells, and embryonic stem cells will overcome shortage of donor organs. The use of the Edmonton protocol has been proved to be the key procedure of clinical islet transplantation. And study of new immunosuppressive drugs and immunomodulators can provide higher rate of success for clinical islet transplantation.

  8. Effects of Energy Dissipation Rate on Islets of Langerhans: Implications for Isolation and Transplantation

    Science.gov (United States)

    Shenkman, Rustin M.; Godoy-Silva, Ruben; Papas, Klearchos K.; Chalmers, Jeffrey J.

    2010-01-01

    Acute physical stresses can occur in the procurement and isolation process and potentially can contribute to islet death or malfunction upon transplantation. A contractional flow device, previously used to subject suspended cells to well-defined hydrodynamic forces, has been modified and used to assess the vulnerability of porcine islets of Langerhans to hydrodynamic forces. The flow profiles and velocity gradients in this modified device were modeled using commercial CFD software and characterized, as in previous studies, with the scalar parameter, energy dissipation rate (EDR). Porcine islets were stressed in a single pass at various stress levels (i.e., values of EDR). Membrane integrity, oxygen uptake rate, caspase 3/7 activity, and insulin release were not affected by the levels of fluid stress tested up to an EDR of 2 × 103 W/m3. Visual observation of the stressed islets suggested that cells at the islet exterior were peeled away at EDR greater than 10,000 W/m3, however, this observation could not be confirmed using image analysis software, which determined the ratio of surface perimeter to total area. The result of this study suggests an upper limit in fluid stress to which islets can be subjected. Such upper limits assist in the design and operation of future islet processing equipment and processes. PMID:19191351

  9. Labeling transplanted mice islet with polyvinylpyrrolidone coated superparamagnetic iron oxide nanoparticles for in vivo detection by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Huang Hai; Xie Qiuping; Kang Muxing; Zhang Bo; Wu Yulian [Department of Surgery, 2nd Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009 (China); Zhang Hui; Chen Jin; Zhai Chuanxin; Yang Deren [State Key Lab of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Jiang Biao, E-mail: wuyulian@medmail.com.c, E-mail: yulianwu2003@yahoo.c [Department of Radiology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009 (China)

    2009-09-09

    Superparamagnetic iron oxide nanoparticles (SPIO) are emerging as a novel probe for noninvasive cell tracking with magnetic resonance imaging (MRI) and have potential wide usage in medical research. In this study, we have developed a method using high-temperature hydrolysis of chelate metal alkoxide complexes to synthesize polyvinylpyrrolidone coated iron oxide nanoparticles (PVP-SPIO), as a biocompatible magnetic agent that can efficiently label mice islet {beta}-cells. The size, crystal structure and magnetic properties of the as-synthesized nanoparticles have been characterized. The newly synthesized PVP-SPIO with high stability, crystallinity and saturation magnetization can be efficiently internalized into {beta}-cells, without affecting viability and function. The imaging of 100 PVP-SPIO-labeled mice islets in the syngeneic renal subcapsular model of transplantation under a clinical 3.0 T MR imager showed high spatial resolution in vivo. These results indicated the great potential application of the PVP-SPIO as an MRI contrast agent for monitoring transplanted islet grafts in the clinical management of diabetes in the near future.

  10. Labeling transplanted mice islet with polyvinylpyrrolidone coated superparamagnetic iron oxide nanoparticles for in vivo detection by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Huang Hai; Xie Qiuping; Kang Muxing; Zhang Bo; Wu Yulian; Zhang Hui; Chen Jin; Zhai Chuanxin; Yang Deren; Jiang Biao

    2009-01-01

    Superparamagnetic iron oxide nanoparticles (SPIO) are emerging as a novel probe for noninvasive cell tracking with magnetic resonance imaging (MRI) and have potential wide usage in medical research. In this study, we have developed a method using high-temperature hydrolysis of chelate metal alkoxide complexes to synthesize polyvinylpyrrolidone coated iron oxide nanoparticles (PVP-SPIO), as a biocompatible magnetic agent that can efficiently label mice islet β-cells. The size, crystal structure and magnetic properties of the as-synthesized nanoparticles have been characterized. The newly synthesized PVP-SPIO with high stability, crystallinity and saturation magnetization can be efficiently internalized into β-cells, without affecting viability and function. The imaging of 100 PVP-SPIO-labeled mice islets in the syngeneic renal subcapsular model of transplantation under a clinical 3.0 T MR imager showed high spatial resolution in vivo. These results indicated the great potential application of the PVP-SPIO as an MRI contrast agent for monitoring transplanted islet grafts in the clinical management of diabetes in the near future.

  11. Pancreatic β-Cell-Derived IP-10/CXCL10 Isletokine Mediates Early Loss of Graft Function in Islet Cell Transplantation.

    Science.gov (United States)

    Yoshimatsu, Gumpei; Kunnathodi, Faisal; Saravanan, Prathab Balaji; Shahbazov, Rauf; Chang, Charles; Darden, Carly M; Zurawski, Sandra; Boyuk, Gulbahar; Kanak, Mazhar A; Levy, Marlon F; Naziruddin, Bashoo; Lawrence, Michael C

    2017-11-01

    Pancreatic islets produce and secrete cytokines and chemokines in response to inflammatory and metabolic stress. The physiological role of these "isletokines" in health and disease is largely unknown. We observed that islets release multiple inflammatory mediators in patients undergoing islet transplants within hours of infusion. The proinflammatory cytokine interferon-γ-induced protein 10 (IP-10/CXCL10) was among the highest released, and high levels correlated with poor islet transplant outcomes. Transgenic mouse studies confirmed that donor islet-specific expression of IP-10 contributed to islet inflammation and loss of β-cell function in islet grafts. The effects of islet-derived IP-10 could be blocked by treatment of donor islets and recipient mice with anti-IP-10 neutralizing monoclonal antibody. In vitro studies showed induction of the IP-10 gene was mediated by calcineurin-dependent NFAT signaling in pancreatic β-cells in response to oxidative or inflammatory stress. Sustained association of NFAT and p300 histone acetyltransferase with the IP-10 gene required p38 and c-Jun N-terminal kinase mitogen-activated protein kinase (MAPK) activity, which differentially regulated IP-10 expression and subsequent protein release. Overall, these findings elucidate an NFAT-MAPK signaling paradigm for induction of isletokine expression in β-cells and reveal IP-10 as a primary therapeutic target to prevent β-cell-induced inflammatory loss of graft function after islet cell transplantation. © 2017 by the American Diabetes Association.

  12. Effect of the Diabetic State on Islet Engraftment and Function in a Large Animal Model of Islet–Kidney Transplantation

    Science.gov (United States)

    Hirakata, Atsushi; Weiss, Matthew; Griesemer, Adam; Shimizu, Akira; Hong, Hanzhou; Habertheuer, Andreas; Tchipashvili, Vaja; Yamada, Kazuhiko; Sachs, David H.

    2018-01-01

    In islet transplantation, in addition to immunologic and ischemic factors, the diabetic/hyperglycemic state of the recipient has been proposed, although not yet validated, as a possible cause of islet toxicity, contributing to islet loss during the engraftment period. Using a miniature swine model of islet transplantation, we have now assessed the effect of a persistent state of hyperglycemia on islet engraftment and subsequent function. An islet–kidney (IK) model previously described by our laboratory was utilized. Three experimental donor animals underwent total pancreatectomy and autologous islet transplantation underneath the renal capsule to prepare an IK at a load of ≤1,000 islet equivalents (IE)/kg donor weight, leading to a chronic diabetic state during the engraftment period (fasting blood glucose >250 mg/dL). Three control donor animals underwent partial pancreatectomy (sufficient to maintain normoglycemia during islet engraftment period) and IK preparation. As in vivo functional readout for islet engraftment, the IKs were transplanted across an immunologic minor or class I mismatch barrier into diabetic, nephrectomized recipients at an islet load of ∼4,500 IE/kg recipient weight. A 12-d course of cyclosporine was administered for tolerance induction. All experimental donors became diabetic and showed signs of end organ injury, while control donors maintained normoglycemia. All recipients of IK from both experimental and control donors achieved glycemic control over long-term follow-up, with reversal of diabetic nephropathy and with similar glucose tolerance tests. In this preclinical, large animal model, neither islet engraftment nor subsequent long-term islet function after transplantation appear to be affected by the diabetic state. PMID:29338381

  13. Pancreas-After-Islet Transplantation in Nonuremic Type 1 Diabetes: A Strategy for Restoring Durable Insulin Independence.

    Science.gov (United States)

    Wisel, S A; Gardner, J M; Roll, G R; Harbell, J; Freise, C E; Feng, S; Kang, S M; Hirose, R; Kaufman, D B; Posselt, A M; Stock, P G

    2017-09-01

    Islet transplantation offers a minimally invasive approach for β cell replacement in diabetic patients with hypoglycemic unawareness. Attempts at insulin independence may require multiple islet reinfusions from distinct donors, increasing the risk of allogeneic sensitization. Currently, solid organ pancreas transplant is the only remaining surgical option following failed islet transplantation in the United States; however, the immunologic impact of repeated exposure to donor antigens on subsequent pancreas transplantation is unclear. We describe a case series of seven patients undergoing solid organ pancreas transplant following islet graft failure with long-term follow-up of pancreatic graft survival and renal function. Despite highly variable panel reactive antibody levels prior to pancreas transplant (mean 27 ± 35%), all seven patients achieved stable and durable insulin independence with a mean follow-up of 6.7 years. Mean hemoglobin A1c values improved significantly from postislet, prepancreas levels (mean 8.1 ± 1.5%) to postpancreas levels (mean 5.3 ± 0.1%; p = 0.0022). Three patients experienced acute rejection episodes that were successfully managed with thymoglobulin and methylprednisolone, and none of these preuremic type 1 diabetic recipients developed stage 4 or 5 chronic kidney disease postoperatively. These results support pancreas-after-islet transplantation with aggressive immunosuppression and protocol biopsies as a viable strategy to restore insulin independence after islet graft failure. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  14. Transplantation of bone marrow derived cells promotes pancreatic islet repair in diabetic mice

    International Nuclear Information System (INIS)

    Gao Xiaodong; Song Lujun; Shen Kuntang; Wang Hongshan; Niu Weixin; Qin Xinyu

    2008-01-01

    The transplantation of bone marrow (BM) derived cells to initiate pancreatic regeneration is an attractive but as-yet unrealized strategy. Presently, BM derived cells from green fluorescent protein transgenic mice were transplanted into diabetic mice. Repair of diabetic islets was evidenced by reduction of hyperglycemia, increase in number of islets, and altered pancreatic histology. Cells in the pancreata of recipient mice co-expressed BrdU and insulin. Double staining revealed β cells were in the process of proliferation. BrdU + insulin - PDX-1 + cells, Ngn3 + cells and insulin + glucagon + cells, which showed stem cells, were also found during β-cell regeneration. The majority of transplanted cells were mobilized to the islet and ductal regions. In recipient pancreas, transplanted cells simultaneously expressed CD34 but did not express insulin, PDX-1, Ngn3, Nkx2.2, Nkx6.1, Pax4, Pax6, and CD45. It is concluded that BM derived cells especially CD34 + cells can promote repair of pancreatic islets. Moreover, both proliferation of β cells and differentiation of pancreatic stem cells contribute to the regeneration of β cells

  15. Transplantation of islet allografts and xenografts in totally pancreatectomized diabetic dogs using the hybrid artificial pancreas.

    Science.gov (United States)

    Monaco, A P; Maki, T; Ozato, H; Carretta, M; Sullivan, S J; Borland, K M; Mahoney, M D; Chick, W L; Muller, T E; Wolfrum, J

    1991-01-01

    Previously the authors reported on a Hybrid Artificial Pancreas device that maintained patent vascular anastomoses in normal dogs and, when seeded with allogeneic canine islets, maintained normal fasting blood sugars (FBS) in diabetic pancreatectomized dogs. Eventual failure of these devices was believed to be related to loss of islet viability and/or insufficient islet mass. The current study evaluates the effect of increased islet mass produced by implantation of two islet-seeded devices in pancreatectomized dogs and compares the results with those from dogs that received a single device. Twelve of fifteen dogs receiving single devices showed initial function as determined by elimination or reduction of exogenous insulin requirement; four showed initial function and seven showed extended function (100 to 284 days). Excessive weight loss (more than 20%), despite normal FBS and insulin dependence, required that four animals in this latter group be killed. Devices seeded with xenogeneic islets have met with limited success. One dog that received two bovine islet-seeded devices achieved function for more than 100 days; the remaining bovine-seeded devices (n = 8) functioned for only 3 to 16 days. Porcine islet-seeded devices were assessed by intravenous glucose tolerance tests (IVGTT). Recipients of two devices seeded with allogeneic islets demonstrated improved IVGTT results when compared to those from pancreatectomized dogs and recipients of single devices but were abnormal when compared to intact animals. Histologic examination of device and autopsy material from all failed experiments was performed and showed no mononuclear cell infiltration of the islet chamber or vascular graft material, only a few incidence of device thrombosis, and varying degrees of islet viability as judged by morphologic and immunohistochemical evaluation. The authors believe they have demonstrated progress toward the development and clinical applicability of the Hybrid Artificial Pancreas

  16. In Vitro and In Vivo Investigation of the Angiogenic Effects of Liraglutide during Islet Transplantation.

    Directory of Open Access Journals (Sweden)

    Allan Langlois

    Full Text Available This study investigated the angiogenic properties of liraglutide in vitro and in vivo and the mechanisms involved, with a focus on Hypoxia Inducible Factor-1α (HIF-1α and mammalian target of rapamycin (mTOR.Rat pancreatic islets were incubated in vitro with 10 μmol/L of liraglutide (Lira for 12, 24 and 48 h. Islet viability was studied by fluorescein diacetate/propidium iodide staining and their function was assessed by glucose stimulation. The angiogenic effect of liraglutide was determined in vitro by the measure of vascular endothelial growth factor (VEGF secretion using enzyme-linked immunosorbent assay and by the evaluation of VEGF and platelet-derived growth factor-α (PDGFα expression with quantitative polymerase chain reaction technic. Then, in vitro and in vivo, angiogenic property of Lira was evaluated using immunofluorescence staining targeting the cluster of differentiation 31 (CD31. To understand angiogenic mechanisms involved by Lira, HIF-1α and mTOR activation were studied using western blotting. In vivo, islets (1000/kg body-weight were transplanted into diabetic (streptozotocin Lewis rats. Metabolic control was assessed for 1 month by measuring body-weight gain and fasting blood glucose.Islet viability and function were respectively preserved and enhanced (p<0.05 with Lira, versus control. Lira increased CD31-positive cells, expression of VEGF and PDGFα (p<0.05 after 24 h in culture. Increased VEGF secretion versus control was also observed at 48 h (p<0.05. Moreover, Lira activated mTOR (p<0.05 signalling pathway. In vivo, Lira improved vascular density (p<0.01, body-weight gain (p<0.01 and reduced fasting blood glucose in transplanted rats (p<0.001.The beneficial effects of liraglutide on islets appeared to be linked to its angiogenic properties. These findings indicated that glucagon-like peptide-1 analogues could be used to improve transplanted islet revascularisation.

  17. Beating diabetes: strategies to improve pancreatic islet transplantation

    NARCIS (Netherlands)

    Hilderink, J.

    2013-01-01

    Type 1 diabetes is a chronic disease that is caused by nearly complete destruction of insulin producing beta-cells in the islets of Langerhans, affecting approximately 25 million people worldwide. Prior to the discovery of insulin, diabetes most certainly led to death. To date, patients with type 1

  18. Evolution of β-Cell Replacement Therapy in Diabetes Mellitus: Islet Cell Transplantation

    Science.gov (United States)

    Jahansouz, Cyrus; Jahansouz, Cameron; Kumer, Sean C.; Brayman, Kenneth L.

    2011-01-01

    Diabetes mellitus remains one of the leading causes of morbidity and mortality worldwide. According to the Centers for Disease Control and Prevention, approximately 23.6 million people in the United States are affected. Of these individuals, 5 to 10% have been diagnosed with Type 1 diabetes mellitus (T1DM), an autoimmune disease. Although it often appears in childhood, T1DM may manifest at any age, leading to significant morbidity and decreased quality of life. Since the 1960s, the surgical treatment for diabetes mellitus has evolved to become a viable alternative to insulin administration, beginning with pancreatic transplantation. While islet cell transplantation has emerged as another potential alternative, its role in the treatment of T1DM remains to be solidified as research continues to establish it as a truly viable alternative for achieving insulin independence. In this paper, the historical evolution, procurement, current status, benefits, risks, and ongoing research of islet cell transplantation are explored. PMID:22013505

  19. The relative contribution of insulin secretory capacity, insulin action, and incretins to metabolic control after islet transplantation in dogs

    NARCIS (Netherlands)

    van der Burg, MPM; van Suylichem, PTR; Guicherit, OR; Frolich, M; Lemkes, HHPJ; Gooszen, HG

    Adequate metabolic control is central to the concept of islet transplantation, but has received limited attention. We studied metabolic control in 8 dogs at 6-9 months after intrasplenic autografting of similar to 25% of the normal mass islets - as compared to 30 controls. A similar posttransplant

  20. Glucoregulation after canine islet transplantation : Contribution of insulin secretory capacity, insulin action, and the entero-insular axis

    NARCIS (Netherlands)

    vanderBurg, MPM; van Suylichem, PTR; Guicherit, OR; Frolich, M; Lemkes, HHPJ; Gooszen, HG

    1997-01-01

    The physiological glucoregulatory mechanisms after islet transplantation have been incompletely investigated, We studied the insulin secretory capacity (ISC) by intravenous arginine stimulation during 35-mM glucose clamps, insulin action during hyperinsulinemic euglycemic clamps, and mixed-meal

  1. Regulation of the JNK3 signaling pathway during islet isolation: JNK3 and c-fos as new markers of islet quality for transplantation.

    Directory of Open Access Journals (Sweden)

    Saida Abdelli

    Full Text Available Stress conditions generated throughout pancreatic islet processing initiate the activation of pro-inflammatory pathways and beta-cell destruction. Our goal is to identify relevant and preferably beta-specific markers to assess the activation of beta-cell stress and apoptotic mechanisms, and therefore the general quality of the islet preparation prior to transplantation. Protein expression and activation were analyzed by Western blotting and kinase assays. ATP measurements were performed by a luminescence-based assay. Oxygen consumption rate (OCR was measured based on standard protocols using fiber optic sensors. Total RNA was used for gene expression analyzes. Our results indicate that pancreas digestion initiates a potent stress response in the islets by activating two stress kinases, c-Jun N-terminal Kinase (JNK and p38. JNK1 protein levels remained unchanged between different islet preparations and following culture. In contrast, levels of JNK3 increased after islet culture, but varied markedly, with a subset of preparations bearing low JNK3 expression. The observed changes in JNK3 protein content strongly correlated with OCR measurements as determined by the Spearman's rank correlation coefficient rho [Formula: see text] in the matching islet samples, while inversely correlating with c-fos mRNA expression [Formula: see text]. In conclusion, pancreas digestion recruits JNK and p38 kinases that are known to participate to beta-cell apoptosis. Concomitantly, the islet isolation alters JNK3 and c-fos expression, both strongly correlating with OCR. Thus, a comparative analysis of JNK3 and c-fos expression before and after culture may provide for novel markers to assess islet quality prior to transplantation. JNK3 has the advantage over all other proposed markers to be islet-specific, and thus to provide for a marker independent of non-beta cell contamination.

  2. Type 1 diabetes : The autoimmune process and islet transplantation

    OpenAIRE

    Jacobson, Stella

    2010-01-01

    Type 1 diabetes (T1D) is an autoimmune disease characterized by the selective loss of the insulin-producing β-cells residing in the islets of Langerhans in the pancreas. Cytokines are involved in diabetes development in the nonobese diabetic (NOD) mouse model. NOD mice over-expressing the suppressor of cytokine signaling (SOCS-1) specifically in the β-cells are protected from T1D. Previous studies showed that immune cells infiltrated the pancreas of SOCS-1-transgenic (tg)...

  3. Transplantation of islet cells across major histocompatibility barriers after total lymphoid irradiation and infusion of allogeneic bone marrow cells

    International Nuclear Information System (INIS)

    Britt, L.D.; Scharp, D.W.; Lacy, P.E.; Slavin, S.

    1982-01-01

    Diabetic Lewis rats (AgB1/L) were evaluated as recipients of allogeneic Wistar-Furth (AgB2/2) isolated adult islets without the use of standard recipient immunosuppression. One group was treated with fractionated total lymphoid irradiation (TLI) and Wistar-Furth bone marrow cell reconstitution to proven chimerism prior to islet transplantation. This group returned to a prediabetic state following Wistar-Furth islet transplantation without any evidence of rejection for 100 days posttransplant. A second group of Lewis rats received only TLI without bone marrow treatment. They gave a varying result following islet transplantation with one recipient showing evidence of prolonged islet survival. A third chimeric control group did not receive isolated islets and did not alter their diabetic state. A fourth group was not given TLI nor donor bone marrow cells and uniformly rejected their allogeneic islets by 7 days. Thus, allogeneic adult islets will survive across major rat histocompatibility barriers using TLI and donor bone marrow chimerism as the only form of immunosuppression

  4. Anticarbohydrate Antibody Repertoires in Patients Transplanted with Fetal Pig Islets Revealed by Glycan Arrays

    DEFF Research Database (Denmark)

    Blixt, Klas Ola; Kumagai-Braesch, A.; Tibell, A.

    2009-01-01

    Ten patients with type I diabetes were transplanted with porcine fetal islet-like cell clusters (ICC) between 1990 and 1993. A significant rise in the anti-a-Gal antibody titers was seen posttransplant, but also non-a-Gal-specific antibodies were detected in some patients. We have reanalyzed...... the carbohydrate specificity of antibodies in the sera from seven of these patients taken before transplantation, 1, 6 and 12 months posttransplantation using a glycan array with 200 structurally defined glycans. The main findings were: (i) prepig ICC transplantation patients had antibodies reactive with terminal...... compounds; (ii) the titers of all carbohydrate-specific antibodies detected before transplantation rose after transplantation; (iii) the kinetics of the antibody responses differed between patients; (iv) in some patients antibodies reacting with Gala1,3Lex and several structures terminated with Neu5Gc...

  5. Impact of anti-insulin antibodies on islet transplantation outcome: data from the GRAGIL Network.

    Science.gov (United States)

    Lablanche, Sandrine; Borot, Sophie; Thaunat, Olivier; Bayle, Francois; Badet, Lionel; Morelon, Emmanuel; Thivolet, Charles; Wojtusciszyn, Anne; Frimat, Luc; Kessler, Laurence; Penfornis, Alfred; Brault, Coralie; Colin, Cyrille; Bosco, Domenico; Berney, Thierry; Benhamou, Pierre Y

    2014-08-27

    In patients with type 1 diabetes, insulin antibodies (IA), altering the pharmacokinetics of circulating insulin, might be associated with high glucose concentration, prolonged hypoglycemia, and higher insulin requirement. The impact of IA on islet transplantation has never been explored. Our aim was to evaluate islet transplantation results at 1 year according to the presence of IA. Our work is a retrospective, case-control study, comparing IA-negative and IA-positive patients among the cohort of patients with type 1 diabetes transplanted within the Swiss-French GRAGIL network between 2003 and 2010. Data about IA were available for 17 patients. Before islet transplantation, 10 patients (59%) were screened positive for IA. At 12 months after transplantation, IA-positive patients reached insulin independence less frequently than IA-negative patients (cumulative incidence of insulin independence, 22.2% vs. 71.4%; P=0.02); β score was ≥7 in 43% of IA-negative patients versus 0% in IA-positive patients (P=0.022). When comparing IA-positive patients with IA-negative patients, insulin dose was 0.15 U/kg (0.10-0.18 U/kg) versus 0.01 U/kg (0-0.09 U/kg) (P=0.2); HbA1c was 6.1% (5.8%-6.3%) versus 6.1% (5.9%-6.8%) (P=0.16); basal C-peptide level was 460 ρmol/L (350-510 ρmol/L) versus 265 ρmol/L (177-405 ρmol/L) (P=0.28); occurrence of hypoglycemia was 12.5% versus 16.5% (P=0.9); and homeostatic model assessment insulin resistance was 1.25 (1-2.4) versus 0.7 (0.52-0.92) (P=0.01). After islet transplantation, IA-positive patients achieved insulin independence less frequently, exhibiting lower β score and higher homeostatic model assessment insulin resistance compared with IA-negative patients. However, in both groups, islet transplantation restored good glycemic control and drastically reduced hypoglycemia and insulin requirements.

  6. Rotational Transport of Islets: The Best Way for Islets to Get around?

    Directory of Open Access Journals (Sweden)

    Rupert Oberhuber

    2013-01-01

    Full Text Available Islet transplantation is a valid treatment option for patients suffering from type 1 diabetes mellitus. To assure optimal islet cell quality, specialized islet isolation facilities have been developed. Utilization of such facilities necessitates transportation of islet cells to distant institutions for transplantation. Despite its importance, a clinically feasible solution for the transport of islets has still not been established. We here compare the functionality of isolated islets from C57BL/6 mice directly after the isolation procedure as well as after two simulated transport conditions, static versus rotation. Islet cell quality was assessed using real-time live confocal microscopy. In vivo islet function after syngeneic transplantation was determined by weight and blood sugar measurements as well as by intraperitoneal glucose tolerance tests. Vascularization of islets was documented by fluorescence microscopy and immunohistochemistry. All viability parameters documented comparable cell viability in the rotary group and the group transplanted immediately after isolation. Functional parameters assessed in vivo displayed no significant difference between these two groups. Moreover, vascularization of islets was similar in both groups. In conclusion, rotary culture conditions allows the maintenance of highest islet quality for at least 15 h, which is comparable to that of freshly isolated islets.

  7. Efficacy of DHMEQ, a NF-κB inhibitor, in islet transplantation: II. Induction DHMEQ treatment ameliorates subsequent alloimmune responses and permits long-term islet allograft acceptance.

    Science.gov (United States)

    Watanabe, Masaaki; Yamashita, Kenichiro; Kamachi, Hirofumi; Kuraya, Daisuke; Koshizuka, Yasuyuki; Shibasaki, Susumu; Asahi, Yoh; Ono, Hitoshi; Emoto, Shin; Ogura, Masaomi; Yoshida, Tadashi; Ozaki, Michitaka; Umezawa, Kazuo; Matsushita, Michiaki; Todo, Satoru

    2013-09-15

    Long-term graft deterioration remains a major obstacle in the success of pancreatic islet transplantation (PITx). Antigen-independent inflammatory and innate immune responses strengthen subsequent antigen-dependent immunity; further, activation of nuclear factor (NF)-κB plays a key role during these responses. In this study, we tested our hypothesis that, by the inhibition of NF-κB activation, the suppression of these early responses after PITx could facilitate graft acceptance. Full major histocompatibility complex (MHC)-mismatched BALB/c (H-2) mice islets were transplanted into streptozotocin-induced diabetic C57BL/6 (B6: H-2) mice. The NF-κB inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) was administered for either 3 or 14 days after PITx. To some PITx recipients, tacrolimus was also administered. Islet allograft survival, alloimmune responses, and in vitro effects of DHMEQ on dendritic cells (DCs) were assessed. With a vehicle treatment, 600 islet allografts were promptly rejected after PITx. In contrast, 3-day treatment with DHMEQ, followed by 2-week treatment with tacrolimus, allowed permanent acceptance of islet allografts. The endogenous danger-signaling molecule high mobility group complex 1 (HMGB1) was elevated in sera shortly after PITx, whereas DHMEQ administration abolished this elevation. DHMEQ suppressed HMGB1-driven cellular activation and proinflammatory cytokine secretion in mouse bone marrow-derived DCs and significantly reduced the capacity of DCs to prime allogeneic T-cell proliferation in vitro. Finally, the DHMEQ plus tacrolimus regimen reverted the diabetic state with only 300 islet allografts. Inhibition of NF-κB activation by DHMEQ shortly after PITx suppresses HMGB1, which activates DCs and strengthens the magnitude of alloimmune responses; this permits long-term islet allograft acceptance, even in case of fewer islet allografts.

  8. Strategies to improve outcome after islet transplantation using the GLP-1 receptor agonist, extendin-4

    OpenAIRE

    Sharma, Amit

    2007-01-01

    Transplantation of pancreatic islets into the liver via the portal vein has emerged as a treatment option for patients with type I diabetes mellitus. However, loss of functional beta cell mass during isolation and following implantation is a major obstacle in obtaining good long-term results. Exendin-4, a glucagonlike peptide-1 (GLP-1) receptor agonist, improves glucose homeostasis in patients with diabetes. It also has anti-apoptotic and beta cell proliferative properties t...

  9. Processing of superparamagnetic iron contrast agent ferucarbotran in transplanted pancreatic islets

    Czech Academy of Sciences Publication Activity Database

    Zacharovová, K.; Berková, Z.; Jirák, D.; Herynek, V.; Vancová, Marie; Dovolilová, E.; Saudek, F.

    2012-01-01

    Roč. 7, č. 6 (2012), s. 485-493 ISSN 1555-4309 Institutional research plan: CEZ:AV0Z60220518 Keywords : magnetic resonance imaging * pancreatic islets * transplantation * superparamagnetic iron oxide nanoparticles * ferucarbotran * β cells * diabetes * immunohistochemistry * transmission electron microscopy Subject RIV: CE - Biochemistry Impact factor: 2.872, year: 2012 http://onlinelibrary.wiley.com/doi/10.1002/cmmi.1477/full

  10. In Vitro and In Vivo Investigation of the Angiogenic Effects of Liraglutide during Islet Transplantation

    Science.gov (United States)

    Langlois, Allan; Mura, Carole; Bietiger, William; Seyfritz, Elodie; Dollinger, Camille; Peronet, Claude; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Sigrist, Séverine

    2016-01-01

    Introduction This study investigated the angiogenic properties of liraglutide in vitro and in vivo and the mechanisms involved, with a focus on Hypoxia Inducible Factor-1α (HIF-1α) and mammalian target of rapamycin (mTOR). Materials and Methods Rat pancreatic islets were incubated in vitro with 10 μmol/L of liraglutide (Lira) for 12, 24 and 48 h. Islet viability was studied by fluorescein diacetate/propidium iodide staining and their function was assessed by glucose stimulation. The angiogenic effect of liraglutide was determined in vitro by the measure of vascular endothelial growth factor (VEGF) secretion using enzyme-linked immunosorbent assay and by the evaluation of VEGF and platelet-derived growth factor-α (PDGFα) expression with quantitative polymerase chain reaction technic. Then, in vitro and in vivo, angiogenic property of Lira was evaluated using immunofluorescence staining targeting the cluster of differentiation 31 (CD31). To understand angiogenic mechanisms involved by Lira, HIF-1α and mTOR activation were studied using western blotting. In vivo, islets (1000/kg body-weight) were transplanted into diabetic (streptozotocin) Lewis rats. Metabolic control was assessed for 1 month by measuring body-weight gain and fasting blood glucose. Results Islet viability and function were respectively preserved and enhanced (p<0.05) with Lira, versus control. Lira increased CD31-positive cells, expression of VEGF and PDGFα (p<0.05) after 24 h in culture. Increased VEGF secretion versus control was also observed at 48 h (p<0.05). Moreover, Lira activated mTOR (p<0.05) signalling pathway. In vivo, Lira improved vascular density (p<0.01), body-weight gain (p<0.01) and reduced fasting blood glucose in transplanted rats (p<0.001). Conclusion The beneficial effects of liraglutide on islets appeared to be linked to its angiogenic properties. These findings indicated that glucagon-like peptide-1 analogues could be used to improve transplanted islet revascularisation

  11. First update of the International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--Chapter 3: Porcine islet product manufacturing and release testing criteria.

    Science.gov (United States)

    Rayat, Gina R; Gazda, Lawrence S; Hawthorne, Wayne J; Hering, Bernhard J; Hosking, Peter; Matsumoto, Shinichi; Rajotte, Ray V

    2016-01-01

    sterility culture results are positive. In terms of the characterization of porcine islet products and product release criteria, the information on the porcine islet products should be acquired from a sample of the final product to be used for transplantation and must include the morphology of the islets, specific identity, purity, viability, and potency of the product. In addition, information on the quantity of the islet products should also be provided in a standardized fashion and this should be in terms of islet equivalents and/or cell numbers. The current consensus was created to provide guidelines that manufacturing facilities may find helpful in the manufacture of and the release criteria for porcine islet products including encapsulated islets and combined islet products. Our intent with the above recommendations is to provide a framework for individual porcine islet manufacturing facilities to ensure a high level of safety for the initiation of Phase 1/2 clinical trials on porcine islet xenotransplantation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Prolongation of experimental islet transplant survival by fractionated splenic irradiation

    International Nuclear Information System (INIS)

    Kolb, E.; Casanova, M.; Largiader, F.

    1980-01-01

    Experiments designed to delay the rejection of intrasplenic pancreatic fragment allotransplants in dogs showed increased transplant survival times from 3.1 days (controls) to 5.5 days with fractionated splenic irradiation and to 7.5 days with combined local irradiation and immunosuppressive chemotherapy. Drug treatment alone had no beneficial effect

  13. Cytomegalovirus prevalence and transmission after islet allograft transplant in patients with type 1 diabetes mellitus.

    Science.gov (United States)

    Hafiz, Muhammad M; Poggioli, Raffaella; Caulfield, Aileen; Messinger, Shari; Geiger, Milene C; Baidal, David A; Froud, Tatiana; Ferreira, Jacqueline V; Tzakis, Andreas G; Ricordi, Camillo; Alejandro, Rodolfo

    2004-10-01

    Cytomegalovirus (CMV) serological status of transplant donors and recipients has important implications on antiviral prophylaxis, morbidity/mortality, donor selection and hospital stay. We evaluated CMV prevalence in our islet transplant candidates (ITC) in comparison with organ donors. We correlated the CMV serological status of our ITC with serology for Epstein-Barr virus and Parvovirus B19, auto-antibodies, patient's age, age at DM onset, duration of DM, gender, race, ABO group, HLA haplotype and C-peptide levels. Cytomegalovirus transmission after islet transplant using the Edmonton regimen was also evaluated. Cytomegalovirus seropositivity varied according to patient group, age, gender and race. Type 1 DM patients had reduced odds of CMV seropositivity when compared with organ donors. In all groups studied, older patients, females, and non-Caucasians were more likely to be CMV seropositive. In addition, no CMV reactivation, infection or disease was observed among our transplanted patients using this steroid-free regimen even after donor/recipient CMV mismatch.

  14. Pravastatin Improves Glucose Regulation and Biocompatibility of Agarose Encapsulated Porcine Islets following Transplantation into Pancreatectomized Dogs

    Directory of Open Access Journals (Sweden)

    Lawrence S. Gazda

    2014-01-01

    Full Text Available The encapsulation of porcine islets is an attractive methodology for the treatment of Type I diabetes. In the current study, the use of pravastatin as a mild anti-inflammatory agent was investigated in pancreatectomized diabetic canines transplanted with porcine islets encapsulated in agarose-agarose macrobeads and given 80 mg/day of pravastatin (n=3 while control animals did not receive pravastatin (n=3. Control animals reached preimplant insulin requirements on days 18, 19, and 32. Pravastatin-treated animals reached preimplant insulin requirements on days 22, 27, and 50. Two animals from each group received a second macrobead implant: control animals remained insulin-free for 15 and 21 days (AUC = 3003 and 5078 mg/dL/24 hr days 1 to 15 and reached preimplant insulin requirements on days 62 and 131. Pravastatin treated animals remained insulin-free for 21 and 34 days (AUC = 1559 and 1903 mg/dL/24 hr days 1 to 15 and reached preimplant insulin requirements on days 38 and 192. Total incidence (83.3% versus 64.3% and total severity (22.7 versus 18.3 of inflammation on tissue surfaces were higher in the control group at necropsy. These findings support pravastatin therapy in conjunction with the transplantation of encapsulated xenogeneic islets for the treatment of diabetes mellitus.

  15. Pancreatectomy and autologous islet transplantation for painful chronic pancreatitis: indications and outcomes.

    Science.gov (United States)

    Bellin, Melena D; Sutherland, David E R; Robertson, R Paul

    2012-08-01

    Total pancreatectomy with intrahepatic autoislet transplantation (TP/IAT) is a definitive treatment for relentlessly painful chronic pancreatitis. Pain relief is reported to be achieved in approximately 80% of patients. Overall, 30% to 40% achieve insulin independence, and 70% of recipients remain insulin independent for > 2 years, sometimes longer if > 300 000 islets are successfully transplanted. Yet, this approach to chronic pancreatitis is underemphasized in the general medical and surgical literature and vastly underused in the United States. This review emphasizes the history and metabolic outcomes of TP/IAT and considers its usefulness in the context of other, more frequently used approaches, such as operative intervention with partial pancreatectomy and/or lateral pancreaticojejunostomy (Puestow procedure), as well as endoscopic retrograde cholangiopancreatography with pancreatic duct modification and stent placement. Distal pancreatectomy and Puestow procedures compromise isolation of islet mass, and adversely affect islet autotransplant outcomes. Therefore, when endoscopic measures fail to relieve pain in severe chronic pancreatitis, we recommend early intervention with TP/IAT.

  16. Sustained NF-κB activation and inhibition in β-cells have minimal effects on function and islet transplant outcomes.

    Directory of Open Access Journals (Sweden)

    Aileen J F King

    Full Text Available The activation of the transcription factor NF-κB leads to changes in expression of many genes in pancreatic β-cells. However, the role of NF-κB activation in islet transplantation has not been fully elucidated. The aim of the present study was to investigate whether the state of NF-κB activation would influence the outcome of islet transplantation. Transgenic mice expressing a dominant active IKKβ (constitutively active or a non-degradable form of IκBα (constitutive inhibition under control of the rat insulin promoter were generated. Islets from these mice were transplanted into streptozotocin diabetic mice in suboptimal numbers. Further, the effects of salicylate (an inhibitor of NF-κB treatment of normal islets prior to transplantation, and the effects of salicylate administration to mice prior to and after islet implantation were evaluated. Transplantation outcomes were not affected using islets expressing a non-degradable form of IκBα when compared to wild type controls. However, the transplantation outcomes using islets isolated from mice expressing a constitutively active mutant of NF-κB were marginally worse, although no aberrations of islet function in vitro could be detected. Salicylate treatment of normal islets or mice had no effect on transplantation outcome. The current study draws attention to the complexities of NF-κB in pancreatic beta cells by suggesting that they can adapt with normal or near normal function to both chronic activation and inhibition of this important transcription factor.

  17. Dual role of interleukin-1β in islet amyloid formation and its β-cell toxicity: Implications for type 2 diabetes and islet transplantation.

    Science.gov (United States)

    Park, Yoo Jin; Warnock, Garth L; Ao, Ziliang; Safikhan, Nooshin; Meloche, Mark; Asadi, Ali; Kieffer, Timothy J; Marzban, Lucy

    2017-05-01

    Islet amyloid, formed by aggregation of human islet amyloid polypeptide (hIAPP), contributes to β-cell failure in type 2 diabetes, cultured and transplanted islets. We previously showed that biosynthetic hIAPP aggregates induce β-cell Fas upregulation and activation of the Fas apoptotic pathway. We used cultured human and hIAPP-expressing mouse islets to investigate: (1) the role of interleukin-1β (IL-1β) in amyloid-induced Fas upregulation; and (2) the effects of IL-1β-induced β-cell dysfunction on pro-islet amyloid polypeptide (proIAPP) processing and amyloid formation. Human and h IAPP -expressing mouse islets were cultured to form amyloid without or with the IL-1 receptor antagonist (IL-1Ra) anakinra, in the presence or absence of recombinant IL-1β. Human islets in which amyloid formation was prevented (amyloid inhibitor or Ad-prohIAPP-siRNA) were cultured similarly. β-cell function, apoptosis, Fas expression, caspase-8 activation, islet IL-1β, β-cell area, β-/α-cell ratio, amyloid formation, and (pro)IAPP forms were assessed. hIAPP aggregates were found to increase IL-1β levels in cultured human islets that correlated with β-cell Fas upregulation, caspase-8 activation and apoptosis, all of which were reduced by IL-1Ra treatment or prevention of amyloid formation. Moreover, IL-1Ra improved culture-induced β-cell dysfunction and restored impaired proIAPP processing, leading to lower amyloid formation. IL-1β treatment potentiated impaired proIAPP processing and increased amyloid formation in cultured human and h IAPP -expressing mouse islets, which were prevented by IL-1Ra. IL-1β plays a dual role by: (1) mediating amyloid-induced Fas upregulation and β-cell apoptosis; (2) inducing impaired proIAPP processing thereby potentiating amyloid formation. Blocking IL-1β may provide a new strategy to preserve β cells in conditions associated with islet amyloid formation. © 2017 John Wiley & Sons Ltd.

  18. Islet Transplantation Provides Superior Glycemic Control With Less Hypoglycemia Compared With Continuous Subcutaneous Insulin Infusion or Multiple Daily Insulin Injections.

    Science.gov (United States)

    Holmes-Walker, Deborah Jane; Gunton, Jenny E; Hawthorne, Wayne; Payk, Marlene; Anderson, Patricia; Donath, Susan; Loudovaris, Tom; Ward, Glenn M; Kay, Thomas Wh; OʼConnell, Philip J

    2017-06-01

    The aim was to compare efficacy of multiple daily injections (MDI), continuous subcutaneous insulin infusion (CSII) and islet transplantation to reduce hypoglycemia and glycemic variability in type 1 diabetes subjects with severe hypoglycemia. This was a within-subject, paired comparison of MDI and CSII and CSII with 12 months postislet transplantation in 10 type 1 diabetes subjects referred with severe hypoglycemia, suitable for islet transplantation. Individuals were assessed with HbA1c, Edmonton Hypoglycemia Score (HYPOscore), continuous glucose monitoring (CGM) and in 8 subjects measurements of glucose variability using standard deviation of glucose (SD glucose) from CGM and continuous overlapping net glycemic action using a 4 hour interval (CONGA4). After changing from MDI to CSII before transplantation, 10 subjects reduced median HYPOscore from 2028 to 1085 (P transplantation, there were significant reductions in all baseline parameters versus CSII, respectively, HbA1c (6.4% cf 8.2%), median HYPOscore (0 cf 1085), mean glucose (7.1 cf 8.6 mmol L), SD glucose (1.7 cf 3.2 mmol/L), and CONGA4 (1.6 cf 3.0). In subjects with severe hypoglycemia suitable for islet transplantation, CSII decreased hypoglycemia frequency and glycemic variability compared with MDI whereas islet transplantation resolved hypoglycemia and further improved glycemic variability regardless of insulin independence.

  19. Using the cost-effectiveness of allogeneic islet transplantation to inform induced pluripotent stem cell-derived β-cell therapy reimbursement.

    Science.gov (United States)

    Archibald, Peter R T; Williams, David J

    2015-11-01

    In the present study a cost-effectiveness analysis of allogeneic islet transplantation was performed and the financial feasibility of a human induced pluripotent stem cell-derived β-cell therapy was explored. Previously published cost and health benefit data for islet transplantation were utilized to perform the cost-effectiveness and sensitivity analyses. It was determined that, over a 9-year time horizon, islet transplantation would become cost saving and 'dominate' the comparator. Over a 20-year time horizon, islet transplantation would incur significant cost savings over the comparator (GB£59,000). Finally, assuming a similar cost of goods to islet transplantation and a lack of requirement for immunosuppression, a human induced pluripotent stem cell-derived β-cell therapy would dominate the comparator over an 8-year time horizon.

  20. Glycemic Stability Through Islet-After-Kidney Transplantation Using an Alemtuzumab-Based Induction Regimen and Long-Term Triple-Maintenance Immunosuppression.

    Science.gov (United States)

    Nijhoff, M F; Engelse, M A; Dubbeld, J; Braat, A E; Ringers, J; Roelen, D L; van Erkel, A R; Spijker, H S; Bouwsma, H; van der Boog, P J M; de Fijter, J W; Rabelink, T J; de Koning, E J P

    2016-01-01

    Pancreatic islet transplantation is performed in a select group of patients with type 1 diabetes mellitus. Immunosuppressive regimens play an important role in long-term islet function. We aimed to investigate the efficacy of islet transplantation in patients with type 1 diabetes and a previous kidney transplantation using an alemtuzumab-based induction regimen and triple maintenance immunosuppression. Patients with type 1 diabetes, who had received a kidney transplant previously, were treated with alemtuzumab as induction therapy for their first islet transplantation and basiliximab induction therapy for subsequent islet transplantations. Maintenance immunosuppression consisted of triple immunosuppression (tacrolimus, mycophenolate mofetil, and prednisolone). Thirteen patients (age 50.9 ± 9.2 years, duration of diabetes 35 ± 9 years) received a total of 22 islet transplantations. One- and 2-year insulin independence was 62% and 42%, respectively; graft function was 100% and 92%, respectively. HbA1c dropped from 57.2 ± 13.1 (7.4 ± 1.2%) to 44.5 ± 11.8 mmol/molHb (6.2 ± 0.9%) (p = 0.003) after 2 years. Six of 13 patients suffered from severe hypoglycemia before islet transplantation. After transplantation, severe hypoglycemia was restricted to the only patient who lost graft function. Creatinine clearance was unchanged. Islet-after-kidney transplantation in patients with type 1 diabetes using an alemtuzumab-based induction regimen leads to considerable islet allograft function and improvement in glycemic control. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  1. Developmental endothelial locus-1 modulates platelet-monocyte interactions and instant blood-mediated inflammatory reaction in islet transplantation.

    Science.gov (United States)

    Kourtzelis, Ioannis; Kotlabova, Klara; Lim, Jong-Hyung; Mitroulis, Ioannis; Ferreira, Anaisa; Chen, Lan-Sun; Gercken, Bettina; Steffen, Anja; Kemter, Elisabeth; Klotzsche-von Ameln, Anne; Waskow, Claudia; Hosur, Kavita; Chatzigeorgiou, Antonios; Ludwig, Barbara; Wolf, Eckhard; Hajishengallis, George; Chavakis, Triantafyllos

    2016-04-01

    Platelet-monocyte interactions are strongly implicated in thrombo-inflammatory injury by actively contributing to intravascular inflammation, leukocyte recruitment to inflamed sites, and the amplification of the procoagulant response. Instant blood-mediated inflammatory reaction (IBMIR) represents thrombo-inflammatory injury elicited upon pancreatic islet transplantation (islet-Tx), thereby dramatically affecting transplant survival and function. Developmental endothelial locus-1 (Del-1) is a functionally versatile endothelial cell-derived homeostatic factor with anti-inflammatory properties, but its potential role in IBMIR has not been previously addressed. Here, we establish Del-1 as a novel inhibitor of IBMIR using a whole blood-islet model and a syngeneic murine transplantation model. Indeed, Del-1 pre-treatment of blood before addition of islets diminished coagulation activation and islet damage as assessed by C-peptide release. Consistently, intraportal islet-Tx in transgenic mice with endothelial cell-specific overexpression of Del-1 resulted in a marked decrease of monocytes and platelet-monocyte aggregates in the transplanted tissues, relative to those in wild-type recipients. Mechanistically, Del-1 decreased platelet-monocyte aggregate formation, by specifically blocking the interaction between monocyte Mac-1-integrin and platelet GPIb. Our findings reveal a hitherto unknown role of Del-1 in the regulation of platelet-monocyte interplay and the subsequent heterotypic aggregate formation in the context of IBMIR. Therefore, Del-1 may represent a novel approach to prevent or mitigate the adverse reactions mediated through thrombo-inflammatory pathways in islet-Tx and perhaps other inflammatory disorders involving platelet-leukocyte aggregate formation.

  2. Combined Microencapsulated Islet Transplantation and Revascularization of Aortorenal Bypass in a Diabetic Nephropathy Rat Model

    Directory of Open Access Journals (Sweden)

    Yunqiang He

    2016-01-01

    Full Text Available Objective. Revascularization of aortorenal bypass is a preferred technique for renal artery stenosis (RAS in diabetic nephropathy (DN patients. Restenosis of graft vessels also should be considered in patients lacking good control of blood glucose. In this study, we explored a combined strategy to prevent the recurrence of RAS in the DN rat model. Methods. A model of DN was established by intraperitoneal injection of streptozotocin. Rats were divided into 4 groups: SR group, MIT group, Com group, and the untreated group. The levels of blood glucose and urine protein were measured, and changes in renal pathology were observed. The expression of monocyte chemoattractant protein-1 (MCP-1 in graft vessels was assessed by immunohistochemical staining. Histopathological staining was performed to assess the pathological changes of glomeruli and tubules. Results. The levels of urine protein and the expression of MCP-1 in graft vessels were decreased after islet transplantation. The injury of glomerular basement membrane and podocytes was significantly ameliorated. Conclusions. The combined strategy of revascularization and microencapsulated islet transplantation had multiple protective effects on diabetic nephropathy, including preventing atherosclerosis in the graft vessels and alleviating injury to the glomerular filtration barrier. This combined strategy may be helpful for DN patients with RAS.

  3. The Study of Non-Viral Nanoscale Delivery Systems for Islet Transplantation

    Science.gov (United States)

    Gutierrez, Diana

    Due to safety concerns associated with using viral systems clinically to expand islet cells and make them available to many more patients, significant emphasis has been placed on producing a safe and effective non-viral delivery system for biological research and gene therapy. To obtain this goal, we propose the use of an innovative technology that utilizes gold nanoparticles (AuNPs) as a non-viral method of delivery. Our laboratory was one of the first to describe the use of AuNPs in human islets and observe AuNPs can penetrate into the core of islets to deliver a gene to the vast majority of the cells, without damaging the cell. Gold nanoparticles proved to be a biocompatible delivery system both in vitro and in vivo. Thus far, gene therapy and molecular biology have focused primarily on delivering DNA of a specific gene into cells. The risk of this approach is that the DNA can be permanently incorporated into the genome and lead to damages in the cell that could result in overexpression of cancerous tumor cells. This risk does not exist with the use of mRNA. Many researchers believe mRNA is too unstable to be used as a molecular tool to overexpress specific proteins. With advances in nanotechnology, and better understanding of the translation process, methods have been developed that allow for expression of specific proteins by intracellular delivery of protein-encoding mRNA. We used AuNPs conjugated to mCherry mRNA to establish a proof of concept of the feasibility of using AuNP-mRNA to achieve increased expression of a specific protein within cells. To do this, we conjugated mCherry mRNA to AuNPs and tested the feasibility for increasing delivery efficacy and preserve functionality of human pancreatic islets. We believe that with this novel technology we can create AuNPs that allow specific mRNA to enter islets and lead to the production of a specific protein within the cell, with the aim to induce beta cell proliferation. In a previous experiment with single

  4. Phase 3 Trial of Transplantation of Human Islets in Type 1 Diabetes Complicated by Severe Hypoglycemia

    Science.gov (United States)

    Hering, Bernhard J.; Clarke, William R.; Bridges, Nancy D.; Eggerman, Thomas L.; Alejandro, Rodolfo; Bellin, Melena D.; Chaloner, Kathryn; Czarniecki, Christine W.; Goldstein, Julia S.; Hunsicker, Lawrence G.; Kaufman, Dixon B.; Korsgren, Olle; Larsen, Christian P.; Luo, Xunrong; Markmann, James F.; Naji, Ali; Oberholzer, Jose; Posselt, Andrew M.; Rickels, Michael R.; Ricordi, Camillo; Robien, Mark A.; Senior, Peter A.; Shapiro, A.M. James; Stock, Peter G.; Turgeon, Nicole A.

    2016-01-01

    OBJECTIVE Impaired awareness of hypoglycemia (IAH) and severe hypoglycemic events (SHEs) cause substantial morbidity and mortality in patients with type 1 diabetes (T1D). Current therapies are effective in preventing SHEs in 50–80% of patients with IAH and SHEs, leaving a substantial number of patients at risk. We evaluated the effectiveness and safety of a standardized human pancreatic islet product in subjects in whom IAH and SHEs persisted despite medical treatment. RESEARCH DESIGN AND METHODS This multicenter, single-arm, phase 3 study of the investigational product purified human pancreatic islets (PHPI) was conducted at eight centers in North America. Forty-eight adults with T1D for >5 years, absent stimulated C-peptide, and documented IAH and SHEs despite expert care were enrolled. Each received immunosuppression and one or more transplants of PHPI, manufactured on-site under good manufacturing practice conditions using a common batch record and standardized lot release criteria and test methods. The primary end point was the achievement of HbA1c transplant. RESULTS The primary end point was successfully met by 87.5% of subjects at 1 year and by 71% at 2 years. The median HbA1c level was 5.6% (38 mmol/mol) at both 1 and 2 years. Hypoglycemia awareness was restored, with highly significant improvements in Clarke and HYPO scores (P > 0.0001). No study-related deaths or disabilities occurred. Five of the enrollees (10.4%) experienced bleeds requiring transfusions (corresponding to 5 of 75 procedures), and two enrollees (4.1%) had infections attributed to immunosuppression. Glomerular filtration rate decreased significantly on immunosuppression, and donor-specific antibodies developed in two patients. CONCLUSIONS Transplanted PHPI provided glycemic control, restoration of hypoglycemia awareness, and protection from SHEs in subjects with intractable IAH and SHEs. Safety events occurred related to the infusion procedure and immunosuppression, including bleeding

  5. ER Stress and β-Cell Pathogenesis of Type 1 and Type 2 Diabetes and Islet Transplantation

    OpenAIRE

    Kataoka, Hitomi Usui; Noguchi, Hirofumi

    2013-01-01

    Endoplasmic reticulum (ER) stress affects the pathogenesis of diabetes. ER stress plays important roles, both in type 1 and type 2 diabetes, because pancreatic β-cells possess highly developed ER for insulin secretion. This review summarizes the relationship between ER stress and the pathogenesis of type 1 and type 2 diabetes. In addition, the association between islet transplantation and ER stress is discussed.

  6. Recent progress in the use and tracking of transplanted islets as a personalized treatment for type 1 diabetes

    NARCIS (Netherlands)

    Paredes-Juarez, Genaro A; de Vos, Paul; Bulte, Jeff W M

    2017-01-01

    Introduction: Type 1 diabetes mellitus (T1DM) is an autoimmune disease in which the pancreas produces insufficient amounts of insulin. T1DM patients require exogenous sources of insulin to maintain euglycemia. Transplantation of naked or microencapsulated pancreatic islets represents an alternative

  7. Australia and New Zealand Islets and Pancreas Transplant Registry Annual Report 2017—Pancreas Waiting List, Recipients, and Donors

    Science.gov (United States)

    Webster, Angela C; Hedley, James; Patekar, Abhijit; Robertson, Paul; Kelly, Patrick J

    2017-01-01

    Abstract This is a registry report from the Australia and New Zealand Islet and Pancreas Transplant Registry. We report data for all solid organ pancreas transplant activity from inception in 1984 to end of 2016. Data analysis was performed using Stata Software version 14 (StataCorp, College Station, Tex). From 1984 to 2016 a total of 756 solid organ pancreas transplants have been performed in Australia and New Zealand, in 738 individuals. In 2016, 55 people received a pancreas transplant. These transplants were performed in Auckland (4), Monash (22), and Westmead (29). In 2016, 50 transplants were simultaneous pancreas kidney, 4 were pancreas after kidney, and 1 was a pancreas transplant alone. PMID:29026874

  8. Transplantation of macroencapsulated human islets within the bioartificial pancreas βAir to patients with type 1 diabetes mellitus.

    Science.gov (United States)

    Carlsson, Per-Ola; Espes, Daniel; Sedigh, Amir; Rotem, Avi; Zimerman, Baruch; Grinberg, Helena; Goldman, Tali; Barkai, Uriel; Avni, Yuval; Westermark, Gunilla T; Carlbom, Lina; Ahlström, Håkan; Eriksson, Olof; Olerud, Johan; Korsgren, Olle

    2017-12-29

    Macroencapsulation devices provide the dual possibility of immunoprotecting transplanted cells while also being retrievable, the latter bearing importance for safety in future trials with stem cell-derived cells. However, macroencapsulation entails a problem with oxygen supply to the encapsulated cells. The βAir device solves this with an incorporated refillable oxygen tank. This phase 1 study evaluated the safety and efficacy of implanting the βAir device containing allogeneic human pancreatic islets into patients with type 1 diabetes. Four patients were transplanted with 1-2 βAir devices, each containing 155 000-180 000 islet equivalents (ie, 1800-4600 islet equivalents per kg body weight), and monitored for 3-6 months, followed by the recovery of devices. Implantation of the βAir device was safe and successfully prevented immunization and rejection of the transplanted tissue. However, although beta cells survived in the device, only minute levels of circulating C-peptide were observed with no impact on metabolic control. Fibrotic tissue with immune cells was formed in capsule surroundings. Recovered devices displayed a blunted glucose-stimulated insulin response, and amyloid formation in the endocrine tissue. We conclude that the βAir device is safe and can support survival of allogeneic islets for several months, although the function of the transplanted cells was limited (Clinicaltrials.gov: NCT02064309). © 2018 The Authors. American Journal of Transplantation published by Wiley Periodicals, Inc. on behalf of The American Society of Transplantation and the American Society of Transplant Surgeons.

  9. Pleckstrin homology-like domain family A, member 3 (PHLDA3 deficiency improves islets engraftment through the suppression of hypoxic damage.

    Directory of Open Access Journals (Sweden)

    Naoaki Sakata

    Full Text Available Islet transplantation is a useful cell replacement therapy that can restore the glycometabolic function of severe diabetic patients. It is known that many transplanted islets failed to engraft, and thus, new approaches for overcoming graft loss that may improve the outcome of future clinical islet transplantations are necessary. Pleckstrin homology-like domain family A, member 3 (PHLDA3 is a known suppressor of neuroendocrine tumorigenicity, yet deficiency of this gene increases islet proliferation, prevents islet apoptosis, and improves their insulin-releasing function without causing tumors. In this study, we examined the potential use of PHLDA3-deficient islets in transplantation. We observed that: 1 transplanting PHLDA3-deficient islets into diabetic mice significantly improved their glycometabolic condition, 2 the improved engraftment of PHLDA3-deficient islets resulted from increased cell survival during early transplantation, and 3 Akt activity was elevated in PHLDA3-deficient islets, especially under hypoxic conditions. Thus, we determined that PHLDA3-deficient islets are more resistant against stresses induced by islet isolation and transplantation. We conclude that use of islets with suppressed PHLDA3 expression could be a novel and promising treatment for improving engraftment and consequent glycemic control in islet transplantation.

  10. Islet Transplantation

    Science.gov (United States)

    ... Easy Advocacy Checklists for Association Events Messaging Tools Recruiting Advocates Local Market Planning Training Webinars News & Events ... cells from attack by the immune system. Several methods are already under study. If successful, the person ...

  11. Effect of a new drug releasing system on microencapsulated islet transplantation

    Science.gov (United States)

    Lu, Binjie; Gao, Qingkun; Liu, Rui; Ren, Ming; Wu, Yan; Jiang, Zaixing; Zhou, Yi

    2015-01-01

    Objective: This study aimed to develop a novel release system for grafted islets. Materials and methods: A graphene oxide-FTY720 release system was constructed to test the drug loading and releasing capacity. The recipient rats were divided into four groups as following: Experiment group A (EG A) and B (EG B); Control group A (CG A) and B (CG B). In each group, (2000±100) IEQ microencapsulated islets were implanted into the abdominal cavity of the recipients with oral FTY720, local graphene oxide-FTY720 injection, without immunosuppressants, and with graphene oxide-saturated solution respectively. We detected the immunological data, the blood glucose level, and pericapsular overgrowth to show the transplantation effect. Results: 31% of adsorptive FTY720 was released within 6 h, and 82% of FTY720 was released within 48 h. From day 5 to 8, the amount of PBL in EG B was significantly less than those in EG A (PGraphene oxide-FTY720 complex showed a drug releasing effect. Local application of graphene-FTY720 releasing system could decrease the amount of peripheral blood lymphocytes (PBL) and the percentage of CD3 and CD8 T lymphocytes in blood for longer time than oral drug application. This releasing system could achieve a better blood glucose control. PMID:26722425

  12. Robot-assisted pancreatoduodenectomy with preservation of the vascular supply for autologous islet cell isolation and transplantation: a case report

    Directory of Open Access Journals (Sweden)

    Giulianotti Piero

    2012-03-01

    Full Text Available Abstract Introduction For patients with chronic pancreatitis presenting with medically intractable abdominal pain, surgical intervention may be the only treatment option. However, extensive pancreatic resections are typically performed open and are associated with a substantial amount of postoperative pain, wound complications and long recovery time. Minimally invasive surgery offers an avenue to improve results; however, current limitations of laparoscopic surgery render its application in the setting of chronic pancreatitis technically demanding. Additionally, pancreatic resections are associated with a high incidence of diabetes. Transplantation of islets isolated from the resected pancreas portion offers a way to prevent post-surgical diabetes; however, preservation of the vascular supply during pancreatic resection, which determines islet cell viability, is technically difficult using current laparoscopic approaches. With recent advances in the surgical field, robotic surgery now provides a means to overcome these obstacles to achieve the end goals of pain relief and preserved endocrine function. We present the first report of a novel, minimally invasive robotic approach for resection of the pancreatic head that preserves vascular supply and enables the isolation of a high yield of viable islets for transplantation. Case presentation A 35-year old Caucasian woman presented with intractable chronic abdominal pain secondary to chronic pancreatitis, with a stricture of her main pancreatic duct at the level of the ampulla of Vater and distal dilatation. She was offered a robotic-assisted pylorus-preserving pancreatoduodenectomy and subsequent islet transplantation, to both provide pain relief and preserve insulin-secretory reserves. Conclusion We present a novel, minimally invasive robotic approach for resection of the pancreatic head with complete preservation of the vascular supply, minimal warm ischemia time (less than three minutes and

  13. Genetically modified human bone marrow derived mesenchymal stem cells for improving the outcome of human islet transplantation.

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    Vaibhav Mundra

    Full Text Available The objective of this study was to determine the potential of human bone marrow derived mesenchymal stem cells (hBMSCs as gene carriers for improving the outcome of human islet transplantation. hBMSCs were characterized for the expression of phenotypic markers and transduced with Adv-hVEGF-hIL-1Ra to overexpress human vascular endothelial growth factor (hVEGF and human interleukin-1 receptor antagonist (hIL-1Ra. Human islets were co-cultured with hBMSCs overexpressing hVEGF and hIL-1Ra. Islet viability was determined by membrane fluorescent method and glucose stimulation test. Transduced hBMSCs and human islets were co-transplanted under the kidney capsule of NOD.Cg-Prkdc(scid Il2rg(tm1Wjl /SzJ (NSG diabetic mice and blood glucose levels were measured over time to demonstrate the efficacy of genetically modified hBMSCs. At the end of study, immunofluorescent staining of kidney section bearing islets was performed for insulin and von Willebrand Factor (vWF. hBMSCs were positive for the expression of CD73, CD90, CD105, CD146 and Stro-1 surface markers as determined by flow cytometry. Transduction of hBMSCs with adenovirus did not affect their stemness and differentiation potential as confirmed by mRNA levels of stem cell markers and adipogenic differentiation of transduced hBMSCs. hBMSCs were efficiently transduced with Adv-hVEGF-hIL-1Ra to overexpress hVEGF and hIL-1Ra. Live dead cell staining and glucose stimulation test have shown that transduced hBMSCs improved the viability of islets against cytokine cocktail. Co-transplantation of human islets with genetically modified hBMSCs improved the glycemic control of diabetic NSG mice as determined by mean blood glucose levels and intraperitoneal glucose tolerance test. Immunofluorescent staining of kidney sections was positive for human insulin and vWF. In conclusion, our results have demonstrated that hBMSCs may be used as gene carriers and nursing cells to improve the outcome of islet

  14. Induction of tolerance and prolongation of islet allograft survival by syngeneic hematopoietic stem cell transplantation in mice.

    Science.gov (United States)

    Yang, Shi-feng; Xue, Wu-jun; Lu, Wan-hong; Xie, Li-yi; Yin, Ai-ping; Zheng, Jin; Sun, Ji-ping; Li, Yang

    2015-10-01

    Syngeneic or autologous hematopoietic stem cells transplantation (HSCT) has been proposed to treat autoimmune diseases because of its immunosuppressive and immunomodulatory effects, which can also contribute to posttransplant antirejection therapy. In this study, we explored the tolerogenic effect of syngeneic HSCT on prolonging islet allograft survival. C57BL/6 mice received syngeneic HSCT plus preconditioning with sublethal irradiation. Then islets of BALB/c mice were transplanted into the renal subcapsular of C57BL/6 mice after chemically induced into diabetes. HSCT mice exhibited improved islet allograft survival and increased serum insulin compared to control mice. Islet allografts of HSCT mice displayed lower level lymphocyte infiltration and stronger insulin staining than control mice. T cells of HSCT mice proliferated poorly in response to allogeneic splenocytes compared to control mice. Mice appeared reversed interferon-γ (IFN-γ)/interleukin-4 (IL-4) ratio to a Th2 immune deviation after syngeneic HSCT. The percentage of CD8(+) T cells was lower, while percentage of CD4(+)CD25(+)Foxp3(+) T regulatory cells (Tregs) was higher in HSCT mice than control mice. HSCT mice showed higher percentage of CTLA-4(+) T cells and expression of CTLA-4 mRNA than control mice. Targeting of CTLA-4 by intraperitoneal injection of anti-CTLA-4 mAb abrogated the effect of syngeneic HSCT on prolonging islet allograft survival, inhibiting activity of T cells in response to alloantigen, promoting Th1 to Th2 immune deviation and up regulating CD4(+)CD25(+)Foxp3(+) Tregs. Syngeneic HSCT plus preconditioning of sublethal irradiation induces tolerance and improves islet allograft survival in fully mismatched mice model. Th1 to Th2 immune deviation, increased CD4(+)CD25(+)Foxp3(+) Tregs and up-regulation of CTLA-4 maybe contribute to the tolerogenic effect induced by syngeneic HSCT. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. MSC in clinics: Liver Transplantation

    OpenAIRE

    DETRY, Olivier

    2014-01-01

    For several years, mesenchymal stem cells (MSC) have been evaluated in vivo and in vitro for their immunomodulatory, anti-inflammatory, anti- ischemia-reperfusion injury and “tissue repair” properties. These characteristics could make them interesting in various clinical applications, and particularly in organ transplantation. Taking advantage of our centre expertise and experience concerning MSC use in graft-versus-host disease after bone marrow transplantation and using already functioning ...

  16. Entrapment of cultured pancreas islets in three-dimensional collagen matrices.

    Science.gov (United States)

    Chao, S H; Peshwa, M V; Sutherland, D E; Hu, W S

    1992-01-01

    In vitro culture of islets of Langerhans decreases their immunogenicity, presumably by eliminating passenger leukocytes and other Ia+ presenting cells within the islets. Islets cultivated in petri dishes either at 37 degrees C or at 25 degrees C gradually disintegrate during culture in a time-dependent manner which is related to the free-floating condition of the islets. Also, a fraction of the islets disperse as single cells and beta-cell aggregates or adhere to the bottom of the culture dishes. Thus, the retrieval rate of transplantable islets is dampened due to their disintegration and spontaneous dispersion in conventional petri dish cultures. Entrapment of freshly harvested islets of Langerhans in a three-dimensional collagen matrix was studied as an alternative method for islet cultivation. The contraction of collagen fibrils during in vitro culture counteracts the dispersion of islets and helps in maintaining their integrity while in culture. It was observed that the entrapped islets maintain satisfactory morphology, viability, and capability of glucose-dependent insulin secretion for over 2 wk. The oxygen consumption rate and glucose metabolism of these islets was not deranged when entrapped in collagen. Also, the retrieval of islets is easier and more efficient than that observed in conventional culture systems. Our results indicate that culture of islets in three-dimensional collagen gels can potentially develop into an ideal system applicable to clinical transplantation of cultured islets or beta-cell aggregates.

  17. Relative reductions in soluble CD30 levels post-transplant predict acute graft function in islet allograft recipients receiving three different immunosuppression protocols.

    Science.gov (United States)

    Hire, Kelly; Hering, Bernhard; Bansal-Pakala, Pratima

    2010-08-01

    Despite advances in islet transplantation, challenges remain in monitoring for anti-islet immune responses. Soluble CD30 (sCD30) has been investigated as a predictor of acute rejection in kidney, lung, and heart transplantation as well as in a single study in human islet cell recipients. In this study, sCD30 levels were retrospectively assessed in 19 allograft recipients treated with three different immunosuppression induction therapies. Soluble CD30 levels were assessed at pre-transplant; early post-transplant (day 4-day 7); one-month post-transplant; and late post-transplant (day 90-day 120) and then correlated with eventual graft outcomes at 1-year follow-up. Results showed no correlation between mean serum sCD30 levels at any point in time pre- or post-transplant and graft function at 1-year follow-up. However, analysis demonstrated that mean sCD30 levels at day 28 or day 90-day 120 decreased from pre-transplant levels in recipients with long-term islet allograft function compared to recipients with partial or non-graft function (a decrease of 43.6+/-25.6% compared to 16.7+/-35.2%, psCD30 levels post-transplant overall. A larger reduction post-transplant correlated with full graft function. The results demonstrate that a relative reduction in sCD30 levels post-transplant may be applicable as a biomarker to monitor graft function in islet allograft recipients. Additionally, knowledge of the impact of various immunosuppression protocols on the timing and extent of changes in post-transplant sCD30 levels could aid in patient-specific tailoring of immunosuppression. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. Age and Early Graft Function Relate With Risk-Benefit Ratio of Allogenic Islet Transplantation Under Antithymocyte Globulin-Mycophenolate Mofetil-Tacrolimus Immune Suppression.

    Science.gov (United States)

    Lee, DaHae; Keymeulen, Bart; Hilbrands, Robert; Ling, Zhidong; Van de Velde, Ursule; Jacobs-Tulleneers-Thevissen, Daniel; Maleux, Geert; Lapauw, Bruno; Crenier, Laurent; De Block, Christophe; Mathieu, Chantal; Pipeleers, Daniel; Gillard, Pieter

    2017-09-01

    Induction therapy with a T cell-depleting agent followed by mycophenolate mofetil and tacrolimus is presently the most frequently used immune suppression (IS) regimen in islet transplantation. This study assesses its safety and tolerability in nonuremic type 1 diabetic recipients. Fifty-one patients (age, between 29 and 63 years) with high glycemic variability and problematic hypoglycemia received intraportal islet grafts under anti-thymocyte globulin-mycophenolate mofetil-tacrolimus protocol. They were followed up for over 48 months for function of the implant and adverse events. Severe hypoglycemia and diabetic ketoacidosis were absent in patients with functioning graft. Immune suppressive therapy was maintained for 48 months in 29 recipients with sustained function (group A), whereas 16 patients stopped earlier due to graft failure (group B) and in 6 for other reasons. Group A was significantly older at the time of implantation and achieved higher graft function at posttransplantation month 6 under similar dose of IS. Prevalence of IS-related side effects was similar in groups A and B, occurring predominantly during the first year posttransplantation. IS-related serious adverse events (SAE) were reported in 47% of patients, with 4 presenting with cytomegalovirus infection and 4 (age, 42-59 years) diagnosed with cancer. Except in 1 patient with cancer, all SAEs resolved after appropriate treatment. These risk/benefit data serve as a basis for clinical decision-making before entering an intraportal islet transplantation protocol. A longer benefit is observed in recipients of higher age (≥40 years), but it is not associated with more side effects and SAE.

  19. Porcine endogenous retroviral nucleic acid in peripheral tissues is associated with migration of porcine cells post islet transplant.

    Science.gov (United States)

    Binette, Tanya M; Seeberger, Karen L; Lyon, James G; Rajotte, Ray V; Korbutt, Gregory S

    2004-07-01

    Porcine islets represent an alternative source of insulin-producing tissue, however, porcine endogenous retrovirus (PERV) remains a concern. In this study, SCID mice were transplanted with nonencapsulated (non-EC), microencapsulated (EC) or macroencapsulated (in a TheraCyte trade mark device) neonatal porcine islets (NPIs), and peripheral tissues were screened for presence of viral DNA and mRNA. To understand the role of an intact immune system in PERV incidence, mice with established NPI grafts were reconstituted with splenocytes. Peripheral tissues were screened for PERV and porcine DNA using PCR. Tissues with positive DNA were analyzed for PERV mRNA using RT-PCR. No significant difference was observed between non-EC and EC transplants regarding presence of PERV or porcine-specific DNA or mRNA. In reconstituted animals, little PERV or porcine DNA, and no PERV mRNA was detected. No PERV or porcine-specific DNA was observed in animals implanted with a TheraCyte trade mark device. In conclusion, an intact immune system significantly lowered the presence of PERV. Microencapsulation of islets did not alter PERV presence, however, macroencapsulation in the TheraCyte device did. Lower PERV incidence coincided with lower porcine DNA in peripheral tissues, linking the presence of PERV to migration of porcine cells.

  20. Evaluation of a collagen-chitosan hydrogel for potential use as a pro-angiogenic site for islet transplantation.

    Directory of Open Access Journals (Sweden)

    Joanne E McBane

    Full Text Available Islet transplantation to treat type 1 diabetes (T1D has shown varied long-term success, due in part to insufficient blood supply to maintain the islets. In the current study, collagen and collagen:chitosan (10:1 hydrogels, +/- circulating angiogenic cells (CACs, were compared for their ability to produce a pro-angiogenic environment in a streptozotocin-induced mouse model of T1D. Initial characterization showed that collagen-chitosan gels were mechanically stronger than the collagen gels (0.7 kPa vs. 0.4 kPa elastic modulus, respectively, had more cross-links (9.2 vs. 7.4/µm(2, and were degraded more slowly by collagenase. After gelation with CACs, live/dead staining showed greater CAC viability in the collagen-chitosan gels after 18 h compared to collagen (79% vs. 69%. In vivo, collagen-chitosan gels, subcutaneously implanted for up to 6 weeks in a T1D mouse, showed increased levels of pro-angiogenic cytokines over time. By 6 weeks, anti-islet cytokine levels were decreased in all matrix formulations ± CACs. The 6-week implants demonstrated increased expression of VCAM-1 in collagen-chitosan implants. Despite this, infiltrating vWF(+ and CXCR4(+ angiogenic cell numbers were not different between the implant types, which may be due to a delayed and reduced cytokine response in a T1D versus non-diabetic setting. The mechanical, degradation and cytokine data all suggest that the collagen-chitosan gel may be a suitable candidate for use as a pro-angiogenic ectopic islet transplant site.

  1. Physicochemical characterization and biocompatibility of alginate-polycation microcapsules designed for islet transplantation

    Science.gov (United States)

    Tam, Susan Kimberly

    Microencapsulation represents a method for immunoprotecting transplanted therapeutic cells or tissues from graft rejection using a physical barrier. This approach is advantageous in that it eliminates the need to induce long-term immunosuppression and allows the option of transplanting non-cadaveric cell sources, such as animal cells and stem cell-derived tissues. The microcapsules that we have investigated are designed to immunoprotect islets of Langerhans (i.e. clusters of insulin-secreting cells), with the goal of treating insulin-dependent diabetes. With the aid of techniques for physicochemical analysis, this research focused on understanding which properties of the microcapsule are the most important for determining its biocompatibility. The objective of this work was to elucidate correlations between the chemical make-up, physicochemical properties, and in vivo biocompatibility of alginate-based microcapsules. Our approach was based on the hypothesis that the immune response to the microcapsules is governed by, and can therefore be controlled by, specific physicochemical properties of the microcapsule and its material components. The experimental work was divided into five phases, each associated with a specific aim : (1) To prove that immunoglobulins adsorb to the surface of alginate-polycation microcapsules, and to correlate this adsorption with the microcapsule chemistry. (2) To test interlaboratory reproducibility in making biocompatible microcapsules, and evaluate the suitability of our materials and fabrication protocols for subsequent studies. (3) To determine which physicochemical properties of alginates affect the in vivo biocompatibility of their gels. (4) To determine which physiochemical properties of alginate-polycation microcapsules are most important for determining their in vivo biocompatibility (5) To determine whether a modestly immunogenic membrane hinders or helps the ability of the microcapsule to immunoprotect islet xenografts in

  2. Real-time assessment of encapsulated neonatal porcine islets prior to clinical xenotransplantation.

    Science.gov (United States)

    Kitzmann, Jennifer P; Law, Lee; Shome, Avik; Muzina, Marija; Elliott, Robert B; Mueller, Kate R; Schuurman, Henk-Jan; Papas, Klearchos K

    2012-01-01

    Porcine islet transplantation is emerging as an attractive option for the treatment of patients with type 1 diabetes, with the possibility of providing islets of higher and more consistent quality and in larger volumes than available from human pancreata. The use of encapsulated neonatal porcine islets (ENPI) is appealing because it can address islet supply limitations while reducing the need for anti-rejection therapy. Pre-transplant characterization of ENPI viability and potency is an essential component of the production process. We applied the validated assay for oxygen consumption rate normalized for DNA content (OCR/DNA) to characterize ENPI viability. ENPI of low viscosity and high m alginate were prepared according to standard methods and characterized at various culture time points up to 5 weeks. The OCR/DNA (nmol/min·mgDNA ± SEM) of ENPI (235 ± 10, n = 9) was comparable to that of free NPI (255 ± 14, n = 13). After encapsulation, NPI OCR/DNA was sustained over a culture period of up to 5 weeks. The average OCR/DNA of ENPI cultured longer than 9 days was higher than that of freshly encapsulated NPI. This is the first characterization of ENPI by a validated and more sensitive method for product viability. The NPI encapsulation process does not compromise viability as measured by OCR/DNA, and ENPI can be cultured for up to 5 weeks with maintenance of viability. ENPI meet or exceed current adult porcine islet product release criteria (established at the University of Minnesota) for preclinical xenotransplantation in terms of OCR/DNA. © 2012 John Wiley & Sons A/S.

  3. Transplante isogênico de ilhotas de Langerhans no fígado de ratos: metodologia para separação e purificação das ilhotas de Langerhans Isogenic islet transplantation on the rat liver: Method for isolation and purification of the rat islets

    Directory of Open Access Journals (Sweden)

    Eleazar CHAIB

    2000-01-01

    Full Text Available A maior indicação do transplante de pâncreas ou de ilhotas de Langerhans é o diabetes mellitus do tipo I. O processo deve suprir as necessidades de insulina mantendo os níveis glicêmicos dentro da normalidade. Estudou-se o transplante isogênico de ilhotas de Langerhans no fígado de ratos WAG-RT1u. Com o método de separação e purificação das ilhotas de Langerhans obteve-se 2.834 ± 551,64 ilhotas com pureza de 83 ± 2,45%. O transplante de 2.834 ± 551,64 ilhotas de Langerhans no fígado destes animais, normalizou a glicemia que chegou a 35 mmol/L após indução do diabetes pela estreptozotocina, ficando em 9,62 ± 2,65 mmol/L nos primeiros 10 dias após o enxerto e 7,43 ± 0,27 mmol/L nos dias subseqüentes (P The major indication for pancreas or islet transplantation is diabetes mellitus type I. This process has to supply the insulin necessity keeping glucose under control. We have studied isogenic islet transplantation on the rat (WAG-RT1u liver. The method of isolation and purification of the islets obtained 2.834 ± 551,64 islets with purity of 83 ± 2,45%. Diabetes was induced by streptozotocin and seric glucose prior transplantation was 35 mmol/L. The islet transplantation of 2.834 ± 551,64 islets in the rat liver has normalized glucose test from 9,62 ± 2,65 mmol/L 10 days after transplantation to 7,43 ± 0,27 mmol/L later in the follow-up (P <0,05. The median survival time of the islets was 73 days. In conclusion both the method of isolation and purification of the islets and islet transplantation was effective in the control of the diabetes induced by streptozotocin with median survival time of both islet and rat more than 73 days when rats were sacrificied.

  4. Regulatory challenges in manufacturing of pancreatic islets.

    Science.gov (United States)

    Linetsky, E; Ricordi, C

    2008-03-01

    At the present time, transplantation of pancreatic islet cells is considered an experimental therapy for a selected cohort of patients with type 1 diabetes, and is conducted under an Investigational New Drug (IND) application. Encouraging results of the Edmonton Protocol published in the year 2000 sparked a renewed interest in clinical transplantation of allogeneic islets, triggering a large number of IND applications for phase I clinical trials. Promising results reported by a number of centers since then prompted the Food and Drug Administration (FDA) to consider the possibility of licensing allogeneic islets as a therapeutic treatment for patients with type 1 diabetes. However, prior to licensure, issues such as safety, purity, efficacy, and potency of the islet product must be addressed. This is complicated by the intricate nature of pancreatic islets and limited characterization prior to transplantation. In this context, control of the manufacturing process plays a critical role in the definition of the final product. Despite significant progress made in standardization of the donor organ preservation methods, reagents used, and characterization assays performed to qualify an islet cell product, control of the isolation process remains a challenge. Within the scope of the FDA regulations, islet cells meet the definition of a biologic product, somatic cell therapy, and a drug. In addition, AABB standards that address cellular therapy products apply to manufacturing facilities accredited by this organization. Control of the source material, isolation process, and final product are critical issues that must be addressed in the context of FDA and other relevant regulations applicable to islet cell products.

  5. Utilization of organs from donors after circulatory death for vascularized pancreas and islet of Langerhans transplantation : recommendations from an expert group

    NARCIS (Netherlands)

    Berney, Thierry; Boffa, Catherine; Augustine, Titus; Badet, Lionel; de Koning, Eelco; Pratschke, Johann; Socci, Carlo; Friend, Peter

    2015-01-01

    Donation after circulatory death (DCD) donors are increasingly being used as a source of pancreas allografts for vascularized organ and islet transplantation. We provide practice guidelines aiming to increase DCD pancreas utilization. We review risk assessment and donor selection criteria. We report

  6. Rapamycin combined with anti-CD45RB mAb and IL-10 or with G-CSF induces tolerance in a stringent mouse model of islet transplantation.

    Directory of Open Access Journals (Sweden)

    Nicola Gagliani

    Full Text Available BACKGROUND: A large pool of preexisting alloreactive effector T cells can cause allogeneic graft rejection following transplantation. However, it is possible to induce transplant tolerance by altering the balance between effector and regulatory T (Treg cells. Among the various Treg-cell types, Foxp3(+Treg and IL-10-producing T regulatory type 1 (Tr1 cells have frequently been associated with tolerance following transplantation in both mice and humans. Previously, we demonstrated that rapamycin+IL-10 promotes Tr1-cell-associated tolerance in Balb/c mice transplanted with C57BL/6 pancreatic islets. However, this same treatment was unsuccessful in C57BL/6 mice transplanted with Balb/c islets (classified as a stringent transplant model. We accordingly designed a protocol that would be effective in the latter transplant model by simultaneously depleting effector T cells and fostering production of Treg cells. We additionally developed and tested a clinically translatable protocol that used no depleting agent. METHODOLOGY/PRINCIPAL FINDINGS: Diabetic C57BL/6 mice were transplanted with Balb/c pancreatic islets. Recipient mice transiently treated with anti-CD45RB mAb+rapamycin+IL-10 developed antigen-specific tolerance. During treatment, Foxp3(+Treg cells were momentarily enriched in the blood, followed by accumulation in the graft and draining lymph node, whereas CD4(+IL-10(+IL-4(- T (i.e., Tr1 cells localized in the spleen. In long-term tolerant mice, only CD4(+IL-10(+IL-4(- T cells remained enriched in the spleen and IL-10 was key in the maintenance of tolerance. Alternatively, recipient mice were treated with two compounds routinely used in the clinic (namely, rapamycin and G-CSF; this drug combination promoted tolerance associated with CD4(+IL-10(+IL-4(- T cells. CONCLUSIONS/SIGNIFICANCE: The anti-CD45RB mAb+rapamycin+IL-10 combined protocol promotes a state of tolerance that is IL-10 dependent. Moreover, the combination of rapamycin+G-CSF induces

  7. Diffusion coefficient of alginate microcapsules used in pancreatic islet transplantation, a method to cure type 1 diabetes

    Science.gov (United States)

    Najdahmadi, Avid; Lakey, Jonathan R. T.; Botvinick, Elliot

    2018-02-01

    Pancreatic islet transplantation is a promising approach of providing insulin in type 1 diabetes. One strategy to protect islets from the host immune system is encapsulation within a porous biocompatible alginate membrane. This encapsulation provides mechanical support to the cells and allows selective diffusion of oxygen, nutrients and insulin while blocking immunoglobulins. These hydrogels form by diffusion of calcium ions into the polymer network and therefore they are highly sensitive to environmental changes and fluctuations in temperature. We investigated the effects of gel concentration, crosslinking time and ambient conditions on material permeability, volume, and rigidity, all of which may change the immunoisolating characteristics of alginate. To measure diffusion coefficient as a method to capture structural changes we studied the diffusion of fluorescently tagged dextrans of different molecular weight into the midplane of alginate microcapsules, the diffusion coefficient is then calculated by fitting observed fluorescence dynamics to the mathematical solution of 1-D diffusion into a sphere. These measurements were performed after incubation in different conditions as well as after an in vivo experiment in six immunocompetent mice for seven days. Additionally, the changes in gel volume after incubation at different temperatures and environmental conditions as well as changes in compression modulus of alginate gels during crosslinking were investigated. Our result show that increase of polymer concentration and crosslinking time leads to a decrease in volume and increase in compression modulus. Furthermore, we found that samples crosslinked and placed in physiological environment, experience an increase in volume. As expected, these volume changes affect diffusion rates of fluorescent dextrans, where volume expansion is correlated with higher calculated diffusion coefficient. This observation is critical to islet protection since higher permeability due

  8. Ancestral genomic duplication of the insulin gene in tilapia: An analysis of possible implications for clinical islet xenotransplantation using donor islets from transgenic tilapia expressing a humanized insulin gene.

    Science.gov (United States)

    Hrytsenko, Olga; Pohajdak, Bill; Wright, James R

    2016-07-03

    Tilapia, a teleost fish, have multiple large anatomically discrete islets which are easy to harvest, and when transplanted into diabetic murine recipients, provide normoglycemia and mammalian-like glucose tolerance profiles. Tilapia insulin differs structurally from human insulin which could preclude their use as islet donors for xenotransplantation. Therefore, we produced transgenic tilapia with islets expressing a humanized insulin gene. It is now known that fish genomes may possess an ancestral duplication and so tilapia may have a second insulin gene. Therefore, we cloned, sequenced, and characterized the tilapia insulin 2 transcript and found that its expression is negligible in islets, is not islet-specific, and would not likely need to be silenced in our transgenic fish.

  9. Trans-arterial xenotransplantation (Tx) of newborn porcine islet (NPI). A clinic trial for type I diabetes

    International Nuclear Information System (INIS)

    Wang Wei; Mo Zhaohui; Huang Zufa; Luo Xianming; Liu Sheng; Ye Bin; Li Bing; Liu Yingxin

    2002-01-01

    Objective: Liver is an important site to host transplanted islets, and implanting of islets by hepatic artery is simpler than by portal vein. Authors' study evaluated efficiency of the method and possible complication in a clinical setting. Methods: From October 1998 to June 2000, 4 type I diabetic patients received 4 x 10 6 (2 cases) and 8 x 10 6 (2 cases) of NPI through hepatic artery. Before Tx, all cases had the history with ketosis and acidosis. Exogenous insulin doses used for these cases were 25-48 units and their GHb was 9%-11%. After Tx, the NPI recipients were treated with immunosuppressants including cyclosporin 8 mg/kg for 12 months, cellcept 2 g/d for 25 days, and methylprednisolone 500 mg at 1 st day, then reduced to 50 mg for 3 days until to 10 mg for 1 month. Liver function and CD4/CD8 of the recipients were measured before and after Tx. Results: After Tx, the dose of exogenous insulin was increased to 60 mg due to methylprednisolone treatment. When methylprednisolone dose was decreased, the requirement for insulin was reduced to 32%-58% of the dose used before Tx. The reduction of required insulin for NPI recipients was proportional to the number of implanted NPI. In addition, GHb was also reduced to normal level (4%-6%) 3 months after Tx. No significant alterations of liver function and CD4 and CD8 in blood were observed after Tx. Conclusion: Trans-arterial intro-hepatic xenotransplantation of NPI is an efficient and safe therapeutic method for type I diabetes. Combination of cyclosporin, cellcept, and methylprednisolone is an effective immunosuppressive strategy for NPI xenograft transplantation

  10. Islet-like clusters derived from mesenchymal stem cells in Wharton's Jelly of the human umbilical cord for transplantation to control type 1 diabetes.

    Directory of Open Access Journals (Sweden)

    Kuo Ching Chao

    Full Text Available BACKGROUND: There is a widespread interest in developing renewable sources of islet-replacement tissue for type I diabetes mellitus. Human mesenchymal cells isolated from the Wharton's jelly of the umbilical cord (HUMSCs, which can be easily obtained and processed compared with embryonic and bone marrow stem cells, possess stem cell properties. HUMSCs may be a valuable source for the generation of islets. METHODOLOGY AND PRINCIPAL FINDINGS: HUMSCs were induced to transform into islet-like cell clusters in vitro through stepwise culturing in neuron-conditioned medium. To assess the functional stability of the islet-like cell clusters in vivo, these cell clusters were transplanted into the liver of streptozotocin-induced diabetic rats via laparotomy. Glucose tolerance was measured on week 12 after transplantation accompanied with immunohistochemistry and electron microscopy analysis. These islet-like cell clusters were shown to contain human C-peptide and release human insulin in response to physiological glucose levels. Real-time RT-PCR detected the expressions of insulin and other pancreatic beta-cell-related genes (Pdx1, Hlxb9, Nkx2.2, Nkx6.1, and Glut-2 in these islet-like cell clusters. The hyperglycemia and glucose intolerance in streptozotocin-induced diabetic rats was significantly alleviated after xenotransplantation of islet-like cell clusters, without the use of immunosuppressants. In addition to the existence of islet-like cell clusters in the liver, some special fused liver cells were also found, which characterized by human insulin and nuclei-positive staining and possessing secretory granules. CONCLUSIONS AND SIGNIFICANCE: In this study, we successfully differentiate HUMSCs into mature islet-like cell clusters, and these islet-like cell clusters possess insulin-producing ability in vitro and in vivo. HUMSCs in Wharton's Jelly of the umbilical cord seem to be the preferential source of stem cells to convert into insulin

  11. Liposome-mediated transfer of IL-1 receptor antagonist gene to dispersed islet cells does not prevent recurrence of disease in syngeneically transplanted NOD mice

    DEFF Research Database (Denmark)

    Saldeen, J; Sandler, S; Bendtzen, K

    2000-01-01

    transplanted non-obese diabetic (NOD) mice. NOD mouse islet cells were transfected using liposome-mediated gene transfer with a human IL-1ra cDNA construct and transplanted two days later to prediabetic NOD mice. Graft infiltration and destruction were monitored three, five and eight days posttransplantation...... by histology and determination of insulin and cytokine content. IL-1ra gene transfer resulted in transient expression of IL-1ra protein in islet cells in vitro as assessed by ELISA and of IL-1ra mRNA in transplanted islets as revealed by RT-PCR. However, both control and IL-1ra transfected NOD grafts exhibited......IL-1beta is cytotoxic to pancreatic beta-cells in vitro but its role in the vicinity of beta-cells in vivo is unknown. We explored whether liposome-mediated transfer of the interleukin 1 receptor antagonist (IL-1ra) gene to islet cells might prevent recurrence of disease in syngeneically...

  12. Organ procurement organization compliance with 21 CFR 1271: a challenge for allogeneic pancreatic islet cell transplantation programs.

    Science.gov (United States)

    Winters, J L; Tran, S A; Gastineau, D A; Padley, D J; Dean, P G; Kudva, Y C

    2009-06-01

    In order to protect tissue recipients, the Food and Drug Administration drafted Title 21, Section 1271 of the Code of Federal Regulations 1271 (21 CFR 1271) to address infectious disease risk. These regulations apply to tissues but not vascularized organs. Pancreatic islet cells are regulated under 21 CFR 1271. These regulations require qualification of suppliers of critical materials and services with regard to 21 CFR 1271 compliance. As part of supplier qualification, all organ procurement organizations (OPOs) in the United States were sent a questionnaire covering the key components of these regulations. Of the 57 OPOs, 29 (51%) were in compliance based upon survey results. Twelve (21%) were not compliant in one or more areas. All indicated plans to become compliant. The remaining 15 (27%) either failed or refused to complete the survey, some indicating 21 CFR 1271 did not apply to OPOs. Using 2006 data, OPOs compliant with 21 CFR 1271 recovered 50% of the organs procured in the United States. These findings represent a challenge for allogeneic islet cell transplant programs whose raw material must comply with 21 CFR 1271. OPOs should work toward understanding and complying with 21 CFR 1271. Regulatory agencies should work toward enhancing safety of the pancreas supply by facilitating compliance through harmonization of requirements.

  13. Differences in glucose-stimulated insulin secretion in vitro of islets from human, nonhuman primate, and porcine origin.

    Science.gov (United States)

    Mueller, Kate R; Balamurugan, A N; Cline, Gary W; Pongratz, Rebecca L; Hooper, Rebecca L; Weegman, Bradley P; Kitzmann, Jennifer P; Taylor, Michael J; Graham, Melanie L; Schuurman, Henk-Jan; Papas, Klearchos K

    2013-01-01

    Porcine islet xenotransplantation is considered a potential cell-based therapy for type 1 diabetes. It is currently being evaluated in diabetic nonhuman primates (NHP) to assess safety and efficacy of the islet product. However, due to a variety of distinct differences between the respective species, including the insulin secretory characteristics of islets, the suitability and predictive value of the preclinical model in the extrapolation to the clinical setting remain a critical issue. Islets isolated from human (n = 3), NHP (n = 2), adult pig (AP, n = 3), and juvenile pig (JP, n = 4) pancreata were perifused with medium at basal glucose (2.5 mm) followed by high glucose (16.7 mm) concentrations. The total glucose-stimulated insulin secretion (GSIS) was calculated from generated insulin secretion profiles. Nonhuman primate islets exhibited GSIS 3-fold higher than AP islets, while AP and JP islets exhibited GSIS 1/3 and 1/30 of human islets, respectively. The insulin content of NHP and AP islets was similar to that of human islets, whereas that of JP islets was 1/5 of human islets. Despite the fact that human, NHP, and AP islets contain similar amounts of insulin, the much higher GSIS for NHP islets than for AP and JP islets suggests the need for increased dosing of islets from JP and AP in pig-to-NHP transplantation. Porcine islet xenotransplantation to humans may require significantly higher dosing given the lower GSIS of AP islets compared to human islets. © 2013 John Wiley & Sons A/S.

  14. Cost effectiveness and value of information analyses of islet cell transplantation in the management of 'unstable' type 1 diabetes mellitus.

    Science.gov (United States)

    Wallner, Klemens; Shapiro, A M James; Senior, Peter A; McCabe, Christopher

    2016-04-09

    Islet cell transplantation is a method to stabilize type 1 diabetes patients with hypoglycemia unawareness and unstable blood glucose levels by reducing insulin dependency and protecting against severe hypoglycemia through restoring endogenous insulin secretion. This study analyses the current cost-effectiveness of this technology and estimates the value of further research to reduce uncertainty around cost-effectiveness. We performed a cost-utility analysis using a Markov cohort model with a mean patient age of 49 to simulate costs and health outcomes over a life-time horizon. Our analysis used intensive insulin therapy (IIT) as comparator and took the provincial healthcare provider perspective. Cost and effectiveness data for up to four transplantations per patient came from the University of Alberta hospital. Costs are expressed in 2012 Canadian dollars and effectiveness in quality-adjusted life-years (QALYs) and life years. To characterize the uncertainty around expected outcomes, we carried out a probabilistic sensitivity analysis within the Bayesian decision-analytic framework. We performed a value-of-information analysis to identify priority areas for future research under various scenarios. We applied a structural sensitivity analysis to assess the dependence of outcomes on model characteristics. Compared to IIT, islet cell transplantation using non-generic (generic) immunosuppression had additional costs of $150,006 ($112,023) per additional QALY, an average gain of 3.3 life years, and a probability of being cost-effective of 0.5 % (28.3 %) at a willingness-to-pay threshold of $100,000 per QALY. At this threshold the non-generic technology has an expected value of perfect information (EVPI) of $260,744 for Alberta. This increases substantially in cost-reduction scenarios. The research areas with the highest partial EVPI are costs, followed by natural history, and effectiveness and safety. Current transplantation technology provides substantial

  15. Prolongation of islet allograft survival

    International Nuclear Information System (INIS)

    Lacy, P.E.; Davie, J.M.; Finke, E.H.; Scharp, D.W.

    1979-01-01

    Pretreatment of donor rats with irradiation and silica followed by in vitro culture of the islets for 1 to 2 days prolonged survival of allografts across a minor histocompatibility barrier if hand-picked, clean islets were used for transplantation. Pretreatment of donor rats with irradiation and silica in conjunction with a single injection of antilymphocyte serum (ALS) into the recipient produced a prolongation of survival of hand-picked islets transplanted across a major histocompatibility barrier

  16. Small Bowel Transplantation: Current Clinical Status

    Directory of Open Access Journals (Sweden)

    David Sigalet

    1991-01-01

    Full Text Available With recent refinements in immunosuppression techniques, the first successful reports of small bowel transplantation in humans have now been made, increasing interest in bowel transplantation among clinicians and patients alike. This article reviews recent developments in understanding of the functional capabilities and requirements for effective immune suppression in bowel transplantation. Both experimental and clinical experience with transplantation are discussed, as are the areas which appear to offer the most promise for future developments. Finally guidelines for consideration of patient selection for this procedure are reviewed.

  17. Birth and death of human β-cells in pancreas from cadaver donors, autopsies, surgical specimens, and islets transplanted into mice

    Science.gov (United States)

    Caballero, Francisco; Siniakowicz, Karolina; Jennifer-Hollister-Lock; Duran, Luisa; Katsuta, Hitoshi; Yamada, Takatsugu; Lei, Ji; Deng, Shaoping; Westermark, Gunilla T.; Markmann, James; Bonner-Weir, Susan; Weir, Gordon C.

    2013-01-01

    There is great interest in the potential of the human endocrine pancreas for regeneration by β-cell replication or neogenesis. Our aim was to explore this potential in adult human pancreases and in both islet and exocrine tissue transplanted into mice. The design was to examine pancreases obtained from cadaver donors, autopsies and fresh surgical specimens and compare these findings with those obtained from islet and duct tissue grafted into the kidney. Islets and exocrine tissue were transplanted into normoglycemic ICR/SCID mice and studied 4 and 14 wk later. β-cell replication as assessed by double staining for insulin and Ki67 was 0.22 ± 0.03 % at 4 wk and 0.13 ± 0.03 % at 14 wk. In contrast, no evidence of β-cell replication could be found in 11 cadaver donor and 10 autopsy pancreases. However, Ki67 staining of β-cells in frozen sections obtained at surgery was comparable to that found in transplanted islets. Evidence for neogenesis in transplanted pancreatic exocrine tissue was supported by finding β-cells within the duct epithelium, and the presence of cells double stained for insulin and cytokeratin 19 (CK19). However, β-cells within the ducts never constituted more than 1% of the CK19 positive cells. With confocal microscopy, 7 of 12 examined cells expressed both markers, consistent with a neogeneic process. Mice with grafts containing islet or exocrine tissue were treated with various combinations exendin-4, gastrin and epidermal growth factor; none increased β-cell replication or stimulated neogenesis. In summary, human β-cells replicate at a low level in islets transplanted into mice and in surgical pancreatic frozen sections but rarely in cadaver donor or autopsy pancreases. The absence of β-cell replication in many adult cadaver or autopsy pancreases could, in part, be an artifact of the postmortem state. Thus, it appears that adult human β-cells maintain a low level of turnover through replication and neogenesis. PMID:23321263

  18. Birth and death of human β-cells in pancreases from cadaver donors, autopsies, surgical specimens, and islets transplanted into mice.

    Science.gov (United States)

    Caballero, Francisco; Siniakowicz, Karolina; Hollister-Lock, Jennifer; Duran, Luisa; Katsuta, Hitoshi; Yamada, Takatsugu; Lei, Ji; Deng, Shaoping; Westermark, Gunilla T; Markmann, James; Bonner-Weir, Susan; Weir, Gordon C

    2014-02-01

    There is great interest in the potential of the human endocrine pancreas for regeneration by β-cell replication or neogenesis. Our aim was to explore this potential in adult human pancreases and in both islet and exocrine tissue transplanted into mice. The design was to examine pancreases obtained from cadaver donors, autopsies, and fresh surgical specimens and compare these findings with those obtained from islet and duct tissue grafted into the kidney. Islets and exocrine tissue were transplanted into normoglycemic ICR-SCID mice and studied 4 and 14 weeks later. β-Cell replication, as assessed by double staining for insulin and Ki67, was 0.22 ± 0.03% at 4 weeks and 0.13 ± 0.03% at 14 weeks. In contrast, no evidence of β-cell replication could be found in 11 cadaver donor and 10 autopsy pancreases. However, Ki67 staining of β-cells in frozen sections obtained at surgery was comparable to that found in transplanted islets. Evidence for neogenesis in transplanted pancreatic exocrine tissue was supported by finding β-cells within the duct epithelium and the presence of cells double stained for insulin and cytokeratin 19 (CK19). However, β-cells within the ducts never constituted more than 1% of the CK19-positive cells. With confocal microscopy, 7 of 12 examined cells expressed both markers, consistent with a neogeneic process. Mice with grafts containing islet or exocrine tissue were treated with various combinations of exendin-4, gastrin, and epidermal growth factor; none increased β-cell replication or stimulated neogenesis. In summary, human β-cells replicate at a low level in islets transplanted into mice and in surgical pancreatic frozen sections, but rarely in cadaver donor or autopsy pancreases. The absence of β-cell replication in many adult cadaver or autopsy pancreases could, in part, be an artifact of the postmortem state. Thus, it appears that adult human β-cells maintain a low level of turnover through replication and neogenesis.

  19. In vivo vascularization of anisotropic channeled porous polylactide-based capsules for islet transplantation: the effects of scaffold architecture and implantation site

    Czech Academy of Sciences Publication Activity Database

    Kasoju, Naresh; Kubies, Dana; Fabryová, E.; Kříž, J.; Kumorek, Marta M.; Sticová, E.; Rypáček, František

    2015-01-01

    Roč. 64, Suppl. 1 (2015), S75-S84 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) EE2.3.30.0029; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61389013 Keywords : diabetes * islet transplantation * subcutaneous Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.643, year: 2015 http://www.biomed.cas.cz/physiolres/pdf/64%20Suppl%201/64_S75.pdf

  20. Isolated human islets require hyperoxia to maintain islet mass, metabolism, and function.

    Science.gov (United States)

    Komatsu, Hirotake; Kang, Dongyang; Medrano, Leonard; Barriga, Alyssa; Mendez, Daniel; Rawson, Jeffrey; Omori, Keiko; Ferreri, Kevin; Tai, Yu-Chong; Kandeel, Fouad; Mullen, Yoko

    2016-02-12

    Pancreatic islet transplantation has been recognized as an effective treatment for Type 1 diabetes; however, there is still plenty of room to improve transplantation efficiency. Because islets are metabolically active they require high oxygen to survive; thus hypoxia after transplant is one of the major causes of graft failure. Knowing the optimal oxygen tension for isolated islets would allow a transplant team to provide the best oxygen environment during pre- and post-transplant periods. To address this issue and begin to establish empirically determined guidelines for islet maintenance, we exposed in vitro cultured islets to different partial oxygen pressures (pO2) and assessed changes in islet volume, viability, metabolism, and function. Human islets were cultured for 7 days in different pO2 media corresponding to hypoxia (90 mmHg), normoxia (160 mmHg), and hyerpoxia (270 or 350 mmHg). Compared to normoxia and hypoxia, hyperoxia alleviated the loss of islet volume, maintaining higher islet viability and metabolism as measured by oxygen consumption and glucose-stimulated insulin secretion responses. We predict that maintaining pre- and post-transplanted islets in a hyperoxic environment will alleviate islet volume loss and maintain islet quality thereby improving transplant outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Engineering of microscale three-dimensional pancreatic islet models in vitro and their biomedical applications.

    Science.gov (United States)

    Gao, Bin; Wang, Lin; Han, Shuang; Pingguan-Murphy, Belinda; Zhang, Xiaohui; Xu, Feng

    2016-08-01

    Diabetes now is the most common chronic disease in the world inducing heavy burden for the people's health. Based on this, diabetes research such as islet function has become a hot topic in medical institutes of the world. Today, in medical institutes, the conventional experiment platform in vitro is monolayer cell culture. However, with the development of micro- and nano-technologies, several microengineering methods have been developed to fabricate three-dimensional (3D) islet models in vitro which can better mimic the islet of pancreases in vivo. These in vitro islet models have shown better cell function than monolayer cells, indicating their great potential as better experimental platforms to elucidate islet behaviors under both physiological and pathological conditions, such as the molecular mechanisms of diabetes and clinical islet transplantation. In this review, we present the state-of-the-art advances in the microengineering methods for fabricating microscale islet models in vitro. We hope this will help researchers to better understand the progress in the engineering 3D islet models and their biomedical applications such as drug screening and islet transplantation.

  2. Mesenchymal stromal cells improve human islet function through released products and extracellular matrix.

    Science.gov (United States)

    Arzouni, Ahmed A; Vargas-Seymour, Andreia; Rackham, Chloe L; Dhadda, Paramjeet; Huang, Guo-Cai; Choudhary, Pratik; Nardi, Nance; King, Aileen J F; Jones, Peter M

    2017-12-01

    The aims of the present study were (i) to determine whether the reported beneficial effects of mesenchymal stromal cells (MSCs) on mouse islet function extend to clinically relevant human tissues (islets and MSCs), enabling translation into improved protocols for clinical human islet transplantation; and (ii) to identify possible mechanisms through which human MSCs influence human islet function. Human islets were co-cultured with human adipose tissue-derived MSCs (hASCs) or pre-treated with its products - extracellular matrix (ECM) and annexin A1 (ANXA1). Mouse islets were pre-treated with mouse MSC-derived ECM. Islet insulin secretory function was assessed in vitro by radioimmunoassay. Quantitative RT-PCR was used to screen human adipMSCs for potential ligands of human islet G-protein-coupled receptors. We show that co-culture with hASCs improves human islet secretory function in vitro , as measured by glucose-stimulated insulin secretion, confirming previous reports using rodent tissues. Furthermore, we demonstrate that these beneficial effects on islet function can be partly attributed to the MSC-derived products ECM and ANXA1. Our results suggest that hASCs have the potential to improve the quality of human islets isolated for transplantation therapy of Type 1 diabetes. Furthermore, it may be possible to achieve improvements in human islet quality in a cell-free culture system by using the MSC-derived products ANXA1 and ECM. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  3. Self-Condensation Culture Enables Vascularization of Tissue Fragments for Efficient Therapeutic Transplantation

    Directory of Open Access Journals (Sweden)

    Yoshinobu Takahashi

    2018-05-01

    Full Text Available Summary: Clinical transplantation of tissue fragments, including islets, faces a critical challenge because of a lack of effective strategies that ensure efficient engraftment through the timely integration of vascular networks. We recently developed a complex organoid engineering method by “self-condensation” culture based on mesenchymal cell-dependent contraction, thereby enabling dissociated heterotypic lineages including endothelial cells to self-organize in a spatiotemporal manner. Here, we report the successful adaptation of this method for generating complex tissues from diverse tissue fragments derived from various organs, including pancreatic islets. The self-condensation of human and mouse islets with endothelial cells not only promoted functionalization in culture but also massively improved post-transplant engraftment. Therapeutically, fulminant diabetic mice were more efficiently treated by a vascularized islet transplant compared with the conventional approach. Given the general limitations of post-transplant vascularization associated with 3D tissue-based therapy, our approach offers a promising means of enhancing efficacy in the context of therapeutic tissue transplantation. : Takahashi et al. report on generating vascularized islet tissue from humans and mice. After transplantation, vascularized islets significantly improve survival of diabetic mice, demonstrating the quick normalization of blood glucose compared with conventional islet transplantation. Keywords: tissue engineering, tissue-based therapy, vascularization, islet transplantation, organoid

  4. Islet Amyloid Polypeptide: Structure, Function, and Pathophysiology

    Directory of Open Access Journals (Sweden)

    Rehana Akter

    2016-01-01

    Full Text Available The hormone islet amyloid polypeptide (IAPP, or amylin plays a role in glucose homeostasis but aggregates to form islet amyloid in type-2 diabetes. Islet amyloid formation contributes to β-cell dysfunction and death in the disease and to the failure of islet transplants. Recent work suggests a role for IAPP aggregation in cardiovascular complications of type-2 diabetes and hints at a possible role in type-1 diabetes. The mechanisms of IAPP amyloid formation in vivo or in vitro are not understood and the mechanisms of IAPP induced β-cell death are not fully defined. Activation of the inflammasome, defects in autophagy, ER stress, generation of reactive oxygen species, membrane disruption, and receptor mediated mechanisms have all been proposed to play a role. Open questions in the field include the relative importance of the various mechanisms of β-cell death, the relevance of reductionist biophysical studies to the situation in vivo, the molecular mechanism of amyloid formation in vitro and in vivo, the factors which trigger amyloid formation in type-2 diabetes, the potential role of IAPP in type-1 diabetes, the development of clinically relevant inhibitors of islet amyloidosis toxicity, and the design of soluble, bioactive variants of IAPP for use as adjuncts to insulin therapy.

  5. Improving Islet Engraftment by Gene Therapy

    Directory of Open Access Journals (Sweden)

    Xiaojie Wang

    2011-01-01

    Full Text Available Islet cell transplantation is currently the only feasible long-term treatment option for patients with type 1 diabetes. However, the majority of transplanted islets experience damage and apoptosis during the isolation process, a blood-mediated inflammatory microenvironment in the portal vein upon islet infusion, hypoxia induced by the low oxygenated milieu, and poor-revascularization-mediated lack of nutrients, and impaired hormone modulation in the local transplanted site. Strategies using genetic modification methods through overexpression or silencing of those proteins involved in promoting new formation of blood vessels or inhibition of apoptosis may overcome these hurdles and improve islet engraftment outcomes.

  6. Systematic screening of imaging biomarkers for the Islets of Langerhans, among clinically available positron emission tomography tracers

    International Nuclear Information System (INIS)

    Karlsson, Filip; Antonodimitrakis, Pantelis Clewemar; Eriksson, Olof

    2015-01-01

    Introduction: Functional imaging could be utilized for visualizing pancreatic islets of Langerhans. Therefore, we present a stepwise algorithm for screening of clinically available positron emission tomography (PET) tracers for their use in imaging of the neuroendocrine pancreas in the context of diabetes. Methods: A stepwise procedure was developed for screening potential islet imaging agents. Suitable PET-tracer candidates were identified by their molecular mechanism of targeting. Clinical abdominal examinations were retrospectively analyzed for pancreatic uptake and retention. The target protein localization in the pancreas was assessed in silico by –omics approaches and the in vitro by binding assays to human pancreatic tissue. Results: Six putative candidates were identified and screened by using the stepwise procedure. Among the tested PET tracers, only [ 11 C]5-Hydroxy-tryptophan passed all steps. The remaining identified candidates were falsified as candidates and discarded following in silico and in vitro screening. Conclusions: Of the six clinically available PET tracers identified, [ 11 C]5-HTP was found to be a promising candidate for beta cell imaging, based on intensity of in vivo pancreatic uptake in humans, and islet specificity as assessed on human pancreatic cell preparations. The flow scheme described herein constitutes a methodology for evaluating putative islet imaging biomarkers among clinically available PET tracers

  7. Detection of the immunologic rejection after xeno-islet transplantation: a study by MR imaging enhanced with superparamagnetic iron oxide marking CD4+ T cell antibody

    International Nuclear Information System (INIS)

    Nie Wei; Tang Yiya; Rong Pengfei; Ye Bin; Ye Zheng; Tong Qiongjuan; Wang Wei

    2008-01-01

    Objective: To evaluate the feasibility of the diagnosis of the early immunologic rejection after xeno-islet transplantation by MR imaging enhanced with superparamagnetic iron oxide (SPIO) marking CD4 + T cell antibody. Methods: Two thousand neonatal porcine islets (NPI)were transplanted under the left renal capsule of BALB/C nude mice. When the grafts could be observed by MRI, 10 7 human PBMC was intraperitoneal injected to nude mouse models to reconstitute the human immunologic system, 20 mice were reconstituted. Before and 3,7,14 days after reconstitution of human immunologic system on BALB/C nude mice, MRI imaging was performed half an hour after intravenous injection of nano-immunomagnetic beads via vena caudatis to observe the grafts' MRI signal. BALB/C nude mice were sacrificed after MRI scanning immediately, the histopathologic examination was assessed on grafts, the results were compared with MRI results. And calculate the sensitivity, specificity, Youden index number and coincidence of the MRI for immunologic rejection. Results: Grafts can be observed by MRI 3 weeks after islet cell transplantation (before immunologic rejection modeling), there is no abnormal MRI signal detected in nude mice' graft region after microbeads injected. Seven days after building of immunologic rejection model, MRI hypo-signal in graft site is shown in the T 2 WI sequence after nano-bioprober injected. Histopathologic assessments were employed on grafts in nude mice immediately (HE and immunohistochemistry staining), the results shown that there are a lot of T lymphocyts infiltrated in graft region, implying the occurrence of immunologic rejection. And the sensitivity, specificity, Youden index number and coincidence is: (72.96±0.24)%, 100%, 0.73±0.24, (88.46±0.13)% respectively. The correct Kappa between the MRI and the imunohistochemistry staining was 0.76. Conclusion: The cellular immunological rejection to xeno-islet grarts can be assessed with nano-bioprobe with anti-CD4

  8. Total Pancreatectomy and Islet Auto-Transplantation in Children for Chronic Pancreatitis. Indication, Surgical Techniques, Post Operative Management and Long-Term Outcomes

    Science.gov (United States)

    Chinnakotla, Srinath; Bellin, Melena D.; Schwarzenberg, Sarah J.; Radosevich, David M.; Cook, Marie; Dunn, Ty B.; Beilman, Gregory J.; Freeman, Martin L.; Balamurugan, A.N.; Wilhelm, Josh; Bland, Barbara; Jimenez-Vega, Jose M; Hering, Bernhard J.; Vickers, Selwyn M.; Pruett, Timothy L.; Sutherland, David E.R.

    2014-01-01

    Objective Describe the surgical technique, complications and long term outcomes of total pancreatectomy and islet auto transplantation (TP-IAT) in a large series of pediatric patients. Summary Background Data Surgical management of childhood pancreatitis is not clear; partial resection or drainage procedures often provide transient pain relief, but long term recurrence is common due to the diffuse involvement of the pancreas. Total pancreatectomy (TP) removes the source of the pain, while islet auto transplantation (IAT) potentially can prevent or minimize TP-related diabetes. Methods Retrospective review of 75 children undergoing TP-IAT for chronic pancreatitis who had failed medical, endoscopic or surgical treatment between 1989–2012. Results Pancreatitis pain and the severity of pain statistically improved in 90% of patients after TP-IAT (p =Puestow (p=0.018), lower body surface area (p=0.048), IEQ per Kg Body Weight (p=0.001) and total IEQ (100,000) (0.004) were associated with insulin independence. By multivariate analysis, 3 factors were associated with insulin independence after TP-IAT:(1) male gender, (2) lower body surface area and the (3) higher total IEQ per kilogram body weight. Total IEQ (100,000) was the single factor most strongly associated with insulin independence (OR = 2.62; p value < 0.001). Conclusions TP-IAT provides sustained pain relief and improved quality of life. The β cell function is dependent on islet yield. TP-IAT is an effective therapy for children with painful pancreatitis that fail medical and or endoscopic management PMID:24509206

  9. Selective Osmotic Shock (SOS)-Based Islet Isolation for Microencapsulation.

    Science.gov (United States)

    Enck, Kevin; McQuilling, John Patrick; Orlando, Giuseppe; Tamburrini, Riccardo; Sivanandane, Sittadjody; Opara, Emmanuel C

    2017-01-01

    Islet transplantation (IT) has recently been shown to be a promising alternative to pancreas transplantation for reversing diabetes. IT requires the isolation of the islets from the pancreas, and these islets can be used to fabricate a bio-artificial pancreas. Enzymatic digestion is the current gold standard procedure for islet isolation but has lingering concerns. One such concern is that it has been shown to damage the islets due to nonselective tissue digestion. This chapter provides a detailed description of a nonenzymatic method that we are exploring in our lab as an alternative to current enzymatic digestion procedures for islet isolation from human and nonhuman pancreatic tissues. This method is based on selective destruction and protection of specific cell types and has been shown to leave the extracellular matrix (ECM) of islets intact, which may thus enhance islet viability and functionality. We also show that these SOS-isolated islets can be microencapsulated for transplantation.

  10. Intraocular in vivo imaging of pancreatic islet cell physiology/pathology

    Directory of Open Access Journals (Sweden)

    Ingo B. Leibiger

    2017-09-01

    Major conclusions: Data provided by us and others demonstrate the high versatility of this imaging platform. The use of ‘reporter islets’ engrafted in the eye, reporting on the status of in situ endogenous islets in the pancreas of the same animal, allows the identification of key-events in the development and progression of diabetes. This will not only serve as a versatile research tool but will also lay the foundation for a personalized medicine approach and will serve as a screening platform for new drugs and/or treatment protocols. ‘Metabolic’ islet transplantation, in which islets engrafted in the eye replace the endogenous beta cells, will allow for the establishment of islet-specific transgenic models and ‘humanized’ mouse models as well as serving as the basis for a new clinical transplantation site for the cure of diabetes.

  11. Cotransplantation of Mesenchymal Stem Cells and Immature Dendritic Cells Potentiates the Blood Glucose Control of Islet Allografts

    Directory of Open Access Journals (Sweden)

    Guanghui Long

    2017-01-01

    Full Text Available Background. Transplantation of islets is a promising alternative to treat type 1 diabetes (T1D, but graft rejection is the major obstacle to its application in clinical practice. We evaluated the effects of mesenchymal stem cells (MSCs and immature dendritic cells (imDCs on islet transplantation in diabetic model. Methods. The streptozotocin T1D model was established in BABL/c mice. Rat islets were isolated and identified with dithizone (DTZ staining. MSCs and imDCs were isolated from bone marrow of syngenic mice. Islets, alone or along with MSCs and/or imDCs, were transplanted to the left kidney capsule of diabetic mice. The blood glucose levels and glycosylated hemoglobin levels after transplantation were monitored. Results. Cotransplantation significantly decreased blood glucose and glycosylated hemoglobin levels in the diabetes mice. Transplantation of 200 islets + 2 × 105 MSCs + 2 × 105 imDCs could not only restore normal blood glucose levels, but also significantly prolong graft survival for 12.6±3.48 days. Conclusions. Cotransplantation of allogenic islets with imDCs and/or MSCs can significantly promote graft survival, reverse hyperglycemia, and effectively control the glycosylated hemoglobin levels.

  12. What's hot, what's new in clinical organ transplantation: report from the American Transplant Congress 2015.

    Science.gov (United States)

    Sung, R S

    2015-11-01

    Innovative and exciting advances in the clinical sciences in organ transplantation were presented at the American Transplant Congress 2015. The full spectrum of transplantation was covered, with important developments in many topics. Key areas covered by presentations included living donor outcomes, optimal utilization and allocation of deceased donors, new immunosuppression regimens, antibody-mediated rejection and tolerance induction. This review highlights some of the most interesting and noteworthy clinical presentations from the meeting. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  13. [Xenogeneic cell therapeutics: Treatment of type 1 diabetes using porcine pancreatic islets and islet cells].

    Science.gov (United States)

    Godehardt, Antonia W; Schilling-Leiß, Dagmar; Sanzenbacher, Ralf; Tönjes, Ralf R

    2015-11-01

    In view of the existing shortage of human donor organs and tissues, xenogeneic cell therapeutics (xCT) offer an alternative for adequate treatment. In particular, porcine pancreatic islets and islet cells have already entered the field of experimental therapy for type-1 diabetes mellitus (T1DM) patients. Thereby, xCT depict challenging products with a glance on medical, ethical, and regulatory questions. With cross-species transplantation (xenotransplantation), the risk of immunological graft rejection as well as the risk of infectious transmission of microbial and viral pathogens must be considered. This includes the bidirectional transmission of microorganisms from graft to host as well as from host to graft. Crossing the border of species requires a critical risk-benefit evaluation as well as a thorough longtime surveillance of transplant recipients after treatment. The international legal and regulatory requirements for xCT are inter alia based on the World Health Organization criteria summarized in the Changsha Communiqué (2008). In the European Union, they were reflected by the European Medicines Agency (EMA) Guideline on Xenogeneic Cell-based Medicinal Products following the implementation of the Regulation on Advanced Therapies (ATMP). On the basis of this regulation, the first non-clinical and clinical experiences were obtained for porcine islets. The results suggest that supportive treatment of T1DM risk patients with xCT may be an alternative to established allogeneic organ transplantation in the future.

  14. Supplements in human islet culture: human serum albumin is inferior to fetal bovine serum.

    Science.gov (United States)

    Avgoustiniatos, Efstathios S; Scott, William E; Suszynski, Thomas M; Schuurman, Henk-Jan; Nelson, Rebecca A; Rozak, Phillip R; Mueller, Kate R; Balamurugan, A N; Ansite, Jeffrey D; Fraga, Daniel W; Friberg, Andrew S; Wildey, Gina M; Tanaka, Tomohiro; Lyons, Connor A; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K

    2012-01-01

    Culture of human islets before clinical transplantation or distribution for research purposes is standard practice. At the time the Edmonton protocol was introduced, clinical islet manufacturing did not include culture, and human serum albumin (HSA), instead of fetal bovine serum (FBS), was used during other steps of the process to avoid the introduction of xenogeneic material. When culture was subsequently introduced, HSA was also used for medium supplementation instead of FBS, which was typically used for research islet culture. The use of HSA as culture supplement was not evaluated before this implementation. We performed a retrospective analysis of 103 high-purity islet preparations (76 research preparations, all with FBS culture supplementation, and 27 clinical preparations, all with HSA supplementation) for oxygen consumption rate per DNA content (OCR/DNA; a measure of viability) and diabetes reversal rate in diabetic nude mice (a measure of potency). After 2-day culture, research preparations exhibited an average OCR/DNA 51% higher (p < 0.001) and an average diabetes reversal rate 54% higher (p < 0.05) than clinical preparations, despite 87% of the research islet preparations having been derived from research-grade pancreata that are considered of lower quality. In a prospective paired study on islets from eight research preparations, OCR/DNA was, on average, 27% higher with FBS supplementation than that with HSA supplementation (p < 0.05). We conclude that the quality of clinical islet preparations can be improved when culture is performed in media supplemented with serum instead of albumin.

  15. Composition and function of macroencapsulated human embryonic stem cell-derived implants: comparison with clinical human islet cell grafts.

    Science.gov (United States)

    Motté, Evi; Szepessy, Edit; Suenens, Krista; Stangé, Geert; Bomans, Myriam; Jacobs-Tulleneers-Thevissen, Daniel; Ling, Zhidong; Kroon, Evert; Pipeleers, Daniel

    2014-11-01

    β-Cells generated from large-scale sources can overcome current shortages in clinical islet cell grafts provided that they adequately respond to metabolic variations. Pancreatic (non)endocrine cells can develop from human embryonic stem (huES) cells following in vitro derivation to pancreatic endoderm (PE) that is subsequently implanted in immune-incompetent mice for further differentiation. Encapsulation of PE increases the proportion of endocrine cells in subcutaneous implants, with enrichment in β-cells when they are placed in TheraCyte-macrodevices and predominantly α-cells when they are alginate-microencapsulated. At posttransplant (PT) weeks 20-30, macroencapsulated huES implants presented higher glucose-responsive plasma C-peptide levels and a lower proinsulin-over-C-peptide ratio than human islet cell implants under the kidney capsule. Their ex vivo analysis showed the presence of single-hormone-positive α- and β-cells that exhibited rapid secretory responses to increasing and decreasing glucose concentrations, similar to isolated human islet cells. However, their insulin secretory amplitude was lower, which was attributed in part to a lower cellular hormone content; it was associated with a lower glucose-induced insulin biosynthesis, but not with lower glucagon-induced stimulation, which together is compatible with an immature functional state of the huES-derived β-cells at PT weeks 20-30. These data support the therapeutic potential of macroencapsulated huES implants but indicate the need for further functional analysis. Their comparison with clinical-grade human islet cell grafts sets references for future development and clinical translation. Copyright © 2014 the American Physiological Society.

  16. Bacterial translocation in clinical intestinal transplantation.

    Science.gov (United States)

    Cicalese, L; Sileri, P; Green, M; Abu-Elmagd, K; Kocoshis, S; Reyes, J

    2001-05-27

    Bacterial translocation (BT) has been suggested to be responsible for the high incidence of infections occurring after small bowel transplantation (SBTx). Bacterial overgrowth, alteration of the mucosal barrier function as a consequence of preservation injury or acute rejection (AR), and potent immunosuppression are all associated with BT. The aim of this study was to evaluate and quantify the correlation of BT with these events. Fifty pediatric SBTx recipients on tacrolimus and prednisone immunosuppression were analyzed. Blood, stool, and liver biopsies and peritoneal fluid were cultured (circa 4000 total specimens) when infection was clinically suspected or as part of follow-up. BT episodes were considered when microorganisms were found simultaneously in blood or liver biopsy and stool. BT (average of 2.0 episodes/patient) was evident in 44% of patients and was most frequently caused by Enterococcus, Staphylococcus, Enterobacter, and Klebsiella. The presence of a colon allograft was associated with a higher rate of BT (75% vs. 33.3%). Furthermore, the transplantation procedure (colon vs. no colon) affected the rate of BT: SBTx=40% vs. 25%, combined liver and SBTx=100% vs. 30%, multivisceral transplantation=25% vs. 50%. AR was associated with 39% of BT episodes. BT followed AR in 9.6% of the cases. In 5.2% of the cases, positive blood cultures without stool confirmation of the bacteria were seen. Prolonged cold ischemia time (CIT) affected BT rate significantly (CIT>9 hr 76% vs. CIT<9 hr 20.8%). This study shows that 1) a substantial percentage of, but not all, BT is associated with AR, 2) the presence of a colon allograft increases the risk for BT, and 3) a long CIT is associated with a high incidence of BT after SBTx.

  17. Immunization after renal transplantation: current clinical practice

    NARCIS (Netherlands)

    Struijk, G. H.; Lammers, A. J. J.; Brinkman, R. J.; Lombarts, M. J. M. H.; van Vugt, M.; van der Pant, K. A. M. I.; ten Berge, I. J. M.; Bemelman, F. J.

    2015-01-01

    The use of potent immunosuppressive drugs and increased travel by renal transplant recipients (RTR) has augmented the risk for infectious complications. Immunizations and changes in lifestyle are protective. The Kidney Disease: Improving Global Outcomes (KDIGO) Transplant Work Group has developed

  18. Clinical aspects of bone marrow transplantation

    International Nuclear Information System (INIS)

    Shmitts, N.; Gassmann, V.; Leffler, G.

    1986-01-01

    Experience of bone marrow transplantation into patients with myeloproliferative syndromes, myelodysplasias and highly malignant lymphomas is presented. Side early and late effects of transplantation are described. The frequency and severity of complications of bone marrow transplantation depend sufficiently on the disease as well as on patient's age and general condition

  19. Ex vivo expanded human regulatory T cells delay islet allograft rejection via inhibiting islet-derived monocyte chemoattractant protein-1 production in CD34+ stem cells-reconstituted NOD-scid IL2rγnull mice.

    Science.gov (United States)

    Xiao, Fang; Ma, Liang; Zhao, Min; Huang, Guocai; Mirenda, Vincenzo; Dorling, Anthony; Lechler, Robert; Lombardi, Giovanna

    2014-01-01

    Type 1 diabetes mellitus (T1DM) is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo.

  20. Ex Vivo Expanded Human Regulatory T Cells Delay Islet Allograft Rejection via Inhibiting Islet-Derived Monocyte Chemoattractant Protein-1 Production in CD34+ Stem Cells-Reconstituted NOD-scid IL2rγnull Mice

    Science.gov (United States)

    Xiao, Fang; Ma, Liang; Zhao, Min; Huang, Guocai; Mirenda, Vincenzo; Dorling, Anthony

    2014-01-01

    Type 1 diabetes mellitus (T1DM) is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo. PMID:24594640

  1. Ex vivo expanded human regulatory T cells delay islet allograft rejection via inhibiting islet-derived monocyte chemoattractant protein-1 production in CD34+ stem cells-reconstituted NOD-scid IL2rγnull mice.

    Directory of Open Access Journals (Sweden)

    Fang Xiao

    Full Text Available Type 1 diabetes mellitus (T1DM is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo.

  2. Effects of Acute Cytomegalovirus Infection on Rat Islet Allograft Survival

    NARCIS (Netherlands)

    Smelt, M. J.; Faas, M. M.; Melgert, B. N.; de Vos, P.; de Haan, Bart; de Haan, Aalzen

    2011-01-01

    Transplantation of pancreatic islets is a promising therapy for the treatment of type 1 diabetes mellitus. However, long-term islet graft survival rates are still unsatisfactory low. In this study we investigated the role of cytomegalovirus (CMV) in islet allograft failure. STZ-diabetic rats

  3. Islet grafting and imaging in a bioengineered intramuscular space.

    Science.gov (United States)

    Witkowski, Piotr; Sondermeijer, Hugo; Hardy, Mark A; Woodland, David C; Lee, Keagan; Bhagat, Govind; Witkowski, Kajetan; See, Fiona; Rana, Abbas; Maffei, Antonella; Itescu, Silviu; Harris, Paul E

    2009-11-15

    Because the hepatic portal system may not be the optimal site for islet transplantation, several extrahepatic sites have been studied. Here, we examine an intramuscular transplantation site, bioengineered to better support islet neovascularization, engraftment, and survival, and we demonstrate that at this novel site, grafted beta cell mass may be quantitated in a real-time noninvasive manner by positron emission tomography (PET) imaging. Streptozotocin-induced rats were pretreated intramuscularly with a biocompatible angiogenic scaffold received syngeneic islet transplants 2 weeks later. The recipients were monitored serially by blood glucose and glucose tolerance measurements and by PET imaging of the transplant site with [11C] dihydrotetrabenazine. Parallel histopathologic evaluation of the grafts was performed using insulin staining and evaluation of microvasularity. Reversal of hyperglycemia by islet transplantation was most successful in recipients pretreated with bioscaffolds containing angiogenic factors when compared with those who received no bioscaffolds or bioscaffolds not treated with angiogenic factors. PET imaging with [11C] dihydrotetrabenazine, insulin staining, and microvascular density patterns were consistent with islet survival, increased levels of angiogenesis, and with reversal of hyperglycemia. Induction of increased neovascularization at an intramuscular site significantly improves islet transplant engraftment and survival compared with controls. The use of a nonhepatic transplant site may avoid intrahepatic complications and permit the use of PET imaging to measure and follow transplanted beta cell mass in real time. These findings have important implications for effective islet implantation outside of the liver and offer promising possibilities for improving islet survival, monitoring, and even prevention of islet loss.

  4. Factors influencing insulin secretion from encapsulated islets

    NARCIS (Netherlands)

    de Haan, BJ; Faas, MM; de Vos, P

    2003-01-01

    Adequate regulation of glucose levels by a microencapsulated pancreatic islet graft requires a minute-to-minute regulation of blood glucose. To design such a transplant, it is mandatory to have sufficient insight in factors influencing the kinetics of insulin secretion by encapsulated islets. The

  5. In vivo evaluation of glucose permeability of an immunoisolation device intended for islet transplantation: a novel application of the microdialysis technique.

    Science.gov (United States)

    Rafael, E; Wernerson, A; Arner, P; Wu, G S; Tibell, A

    1999-01-01

    Immunoisolation devices consist of semipermeable membranes chosen to protect the islets from the immune system but still allow sufficient passage of nutrients, oxygen, and the therapeutic products, insulin. The exchange between the device and the microcirculation will influence the survival of the graft as well as the metabolic efficacy of the islet implant. Glucose is the important trigger factor for insulin secretion. In this study, we evaluate the in vivo glucose permeability of the Theracyte immunoisolation device at various times after implantation. Empty devices were implanted s.c. in rats. The glucose kinetics in the device was compared to that in the SC tissue during i.v. glucose tolerance tests (IVGTTs), using the microdialysis technique. In rats studied on day 1, or 1, 2, and 4 weeks after implantation, the peak glucose levels (Cmax) were significantly lower, the times-to-peak (TTP) were significantly longer, and the areas under the curve during the first 40 min (AUC(0-40)) were significantly smaller in the device than in the SC fat. However, at 3 months all parameters improved and Cmax, TTP, and AUC(0-40) in the device did not differ significantly from those measured in the SC fat. Thus, during the first 4 weeks the device constitutes a significant diffusion barrier, but at 3 months the exchange between the lumen of devices and the blood stream improves. Our data indicate that implantation of the device several months before transplantation of the cellular graft would improve the exchange across the membrane during the early posttransplant period. This should have positive effects on graft survival and function. We also suggest that microdialysis is a useful tool for evaluating the in vivo performance of macroencapsulation devices.

  6. PEGylated bilirubin nanoparticle as an anti-oxidative and anti-inflammatory demulcent in pancreatic islet xenotransplantation.

    Science.gov (United States)

    Kim, Min Jun; Lee, Yonghyun; Jon, Sangyong; Lee, Dong Yun

    2017-07-01

    Transplanted islets suffer hypoxic stress, which leads to nonspecific inflammation. This is the major cause of islet graft failure during the early stage of intrahepatic islet transplantation. Although bilirubin has shown potent anti-oxidative and anti-inflammatory functions, its clinical applications have been limited due to its insolubility and short half-life. To overcome this problem, novel amphiphilic bilirubin nanoparticles are designed. Hydrophilic poly(ethylene glycol) (PEG) is conjugated to the hydrophobic bilirubin molecule. Then, the PEG-bilirubin conjugates form nanoparticles via self-assembly, i.e., so-called to BRNPs. BRNPs can protect islet cells not only from chemically induced oxidative stress by scavenging reactive oxygen species molecules, but also from activated macrophages by suppressing cytokine release. Importantly, in vivo experiments demonstrate that BRNP treatment can dramatically and significantly prolong islet graft survival compared to bilirubin treatment. In addition, immunohistochemical analysis shows BRNPs have potent anti-oxidative and anti-inflammatory capabilities. Collectively, novel BRNPs can be a new potent remedy for successful islet transplantation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Fecal Microbiota Transplantation: Clinical and experimental studies

    NARCIS (Netherlands)

    van Nood, E.

    2015-01-01

    In this thesis, several aspects of donor feces infusion, also called Fecal Microbiota Transplantation (FMT), are investigated. Historically, FMTs are given mainly for antibiotic associated diarrhea, caused by the anaerobic bacteria Clostridium difficile. Clostridium difficile infections (CDI) are

  8. The first clinical liver transplantation of Brazil revisited.

    Science.gov (United States)

    Bacchella, T; Machado, M C C

    2004-05-01

    The first clinical orthotopic liver transplantation in Brazil was performed on August 5, 1968. The patient was awake after surgery and died on the seventh postoperative day due to subdural hematoma, bronchopneumonia, renal failure, and graft rejection. The report of this case is important to understand the evolution of clinical liver transplantation in Brazil, where this procedure is now routinely carried out in many medical centers.

  9. Tacrolimus inhibits the revascularization of isolated pancreatic islets.

    Directory of Open Access Journals (Sweden)

    Ryuichi Nishimura

    Full Text Available AIMS: Immunosuppressive drugs could be crucial factors for a poor outcome after islet allotransplantation. Unlike rapamycin, the effects of tacrolimus, the current standard immunosuppressant used in islet transplantation, on graft revascularization remain unclear. We examined the effects of tacrolimus on islet revascularization using a highly sensitive imaging system, and analyzed the gene expression in transplanted islets by introducing laser microdissection techniques. METHODS: Islets isolated from C57BL/6-Tg (CAG-EGFP mice were transplanted into the nonmetallic dorsal skinfold chamber on the recipients. Balb/c athymic mice were used as recipients and were divided into two groups: including a control group (n = 9 and tacrolimus-treated group (n = 7. The changes in the newly-formed vessels surrounding the islet grafts were imaged and semi-quantified using multi-photon laser-scanning microscopy and a Volocity system. Gene expression in transplanted islets was analyzed by the BioMark dynamic system. RESULTS: The revascularization process was completed within 14 days after pancreatic islet transplantation at subcutaneous sites. The newly-formed vascular volume surrounding the transplanted islets in the tacrolimus-treated group was significantly less than that in the control group (p<0.05. Although the expression of Vegfa (p<0.05 and Ccnd1 (p<0.05 was significantly upregulated in the tacrolimus-treated group compared with that of the control group, no differences were observed between the groups in terms of other types of gene expression. CONCLUSIONS: The present study demonstrates that tacrolimus inhibits the revascularization of isolated pancreatic islets without affecting the characteristics of the transplanted grafts. Further refinements of this immunosuppressive regimen, especially regarding the revascularization of islet grafts, could improve the outcome of islet allotransplantation.

  10. Induction of Protective Genes Leads to Islet Survival and Function

    Directory of Open Access Journals (Sweden)

    Hongjun Wang

    2011-01-01

    Full Text Available Islet transplantation is the most valid approach to the treatment of type 1 diabetes. However, the function of transplanted islets is often compromised since a large number of β cells undergo apoptosis induced by stress and the immune rejection response elicited by the recipient after transplantation. Conventional treatment for islet transplantation is to administer immunosuppressive drugs to the recipient to suppress the immune rejection response mounted against transplanted islets. Induction of protective genes in the recipient (e.g., heme oxygenase-1 (HO-1, A20/tumor necrosis factor alpha inducible protein3 (tnfaip3, biliverdin reductase (BVR, Bcl2, and others or administration of one or more of the products of HO-1 to the donor, the islets themselves, and/or the recipient offers an alternative or synergistic approach to improve islet graft survival and function. In this perspective, we summarize studies describing the protective effects of these genes on islet survival and function in rodent allogeneic and xenogeneic transplantation models and the prevention of onset of diabetes, with emphasis on HO-1, A20, and BVR. Such approaches are also appealing to islet autotransplantation in patients with chronic pancreatitis after total pancreatectomy, a procedure that currently only leads to 1/3 of transplanted patients being diabetes-free.

  11. Separation of empty microcapsules after microencapsulation of porcine neonatal islets.

    Science.gov (United States)

    Shin, Soojeong; Yoo, Young Je

    2013-12-01

    Pancreatic islet transplantation is used to treat diabetes mellitus that has minimal complications and avoids hypoglycemic shock. Conformal microencapsulation of pancreatic islets improves their function by blocking immunogenic molecules while protecting fragile islets. However, production of empty alginate capsules during microencapsulation causes enlargement of the transplantation volume of the encapsulated islets and interferes with efficient transfer of nutrients and insulin. In this study, empty alginate capsules were separated after microencapsulation of neonatal porcine islet-like cell clusters (NPCC) using density-gradient centrifugation. Densities of NPCC and alginate capsules were determined using Percoll. Encapsulation products following alginate removal were 97 % of products, with less than 10 % of the capsules remaining empty. The viability of this process compared with manually-selected encapsulated islets indicates the separation process does not harm islets.

  12. Continuous Quadrupole Magnetic Separation of Islets during Digestion Improves Purified Porcine Islet Viability.

    Science.gov (United States)

    Weegman, Bradley P; Kumar Sajja, Venkata Sunil; Suszynski, Thomas M; Rizzari, Michael D; Scott Iii, William E; Kitzmann, Jennifer P; Mueller, Kate R; Hanley, Thomas R; Kennedy, David J; Todd, Paul W; Balamurugan, Appakalai N; Hering, Bernhard J; Papas, Klearchos K

    2016-01-01

    Islet transplantation (ITx) is an emerging and promising therapy for patients with uncontrolled type 1 diabetes. The islet isolation and purification processes require exposure to extended cold ischemia, warm-enzymatic digestion, mechanical agitation, and use of damaging chemicals for density gradient separation (DG), all of which reduce viable islet yield. In this paper, we describe initial proof-of-concept studies exploring quadrupole magnetic separation (QMS) of islets as an alternative to DG to reduce exposure to these harsh conditions. Three porcine pancreata were split into two parts, the splenic lobe (SPL) and the combined connecting/duodenal lobes (CDL), for paired digestions and purifications. Islets in the SPL were preferentially labeled using magnetic microparticles (MMPs) that lodge within the islet microvasculature when infused into the pancreas and were continuously separated from the exocrine tissue by QMS during the collection phase of the digestion process. Unlabeled islets from the CDL were purified by conventional DG. Islets purified by QMS exhibited significantly improved viability (measured by oxygen consumption rate per DNA, p < 0.03) and better morphology relative to control islets. Islet purification by QMS can reduce the detrimental effects of prolonged exposure to toxic enzymes and density gradient solutions and substantially improve islet viability after isolation.

  13. Continuous Quadrupole Magnetic Separation of Islets during Digestion Improves Purified Porcine Islet Viability

    Directory of Open Access Journals (Sweden)

    Bradley P. Weegman

    2016-01-01

    Full Text Available Islet transplantation (ITx is an emerging and promising therapy for patients with uncontrolled type 1 diabetes. The islet isolation and purification processes require exposure to extended cold ischemia, warm-enzymatic digestion, mechanical agitation, and use of damaging chemicals for density gradient separation (DG, all of which reduce viable islet yield. In this paper, we describe initial proof-of-concept studies exploring quadrupole magnetic separation (QMS of islets as an alternative to DG to reduce exposure to these harsh conditions. Three porcine pancreata were split into two parts, the splenic lobe (SPL and the combined connecting/duodenal lobes (CDL, for paired digestions and purifications. Islets in the SPL were preferentially labeled using magnetic microparticles (MMPs that lodge within the islet microvasculature when infused into the pancreas and were continuously separated from the exocrine tissue by QMS during the collection phase of the digestion process. Unlabeled islets from the CDL were purified by conventional DG. Islets purified by QMS exhibited significantly improved viability (measured by oxygen consumption rate per DNA, p<0.03 and better morphology relative to control islets. Islet purification by QMS can reduce the detrimental effects of prolonged exposure to toxic enzymes and density gradient solutions and substantially improve islet viability after isolation.

  14. Vitality of pancreatic islets labeled for magnetic resonance imaging with iron particles.

    Science.gov (United States)

    Berkova, Z; Kriz, J; Girman, P; Zacharovova, K; Koblas, T; Dovolilova, E; Saudek, F

    2005-10-01

    We previously described an in vivo method for pancreatic islet visualization using magnetic resonance imaging with the aid of superparamagnetic nanoparticles of iron oxide (Resovist) or by magnetic beads precoated with antibodies (Dynabeads). The aim of this study was to investigate the in vitro effect of islet labeling on their quality. Isolated rat islets were cultivated for 48 hours with a contrast agent or, in the case of magnetic antibody-coated beads, for only 2 hours. The ability to secrete insulin was tested by a static insulin release assay and the results were expressed as a stimulation index. Staining with propidium iodide and acridine orange was performed to determine the ratio of live to dead cells. Stimulation indices in the Resovist islets (n = 23) vs controls (n = 14) were 15.3 and 15.0, respectively, and in the Dynabeads islets (n = 15) vs controls (n = 12) 21.3 and 19.9, respectively. The vitality of the Resovist islets vs controls determined by live/dead cells ratio was 90.8% and 91.1%, respectively (n = 20), and in the Dynabeads islets vs controls was 89.4% and 91.8%, respectively (n = 11). Islet labeling with the contrast agent as well as with specific antibodies with iron beads did not change the vitality and insulin-secreting capacity assessed in vitro (P > .05). Magnetic resonance using iron nanoparticles represents the only method for in-vivo visualization of transplanted islets so far. Our data represent an important contribution for its clinical use.

  15. Clinical outcomes of facial transplantation: a review.

    Science.gov (United States)

    Shanmugarajah, Kumaran; Hettiaratchy, Shehan; Clarke, Alex; Butler, Peter E M

    2011-01-01

    A total of 18 composite tissue allotransplants of the face have currently been reported. Prior to the start of the face transplant programme, there had been intense debate over the risks and benefits of performing this experimental surgery. This review examines the surgical, functional and aesthetic, immunological and psychological outcomes of facial transplantation thus far, based on the predicted risks outlined in early publications from teams around the world. The initial experience has demonstrated that facial transplantation is surgically feasible. Functional and aesthetic outcomes have been very encouraging with good motor and sensory recovery and improvements to important facial functions observed. Episodes of acute rejection have been common, as predicted, but easily controlled with increases in systemic immunosuppression. Psychological improvements have been remarkable and have resulted in the reintegration of patients into the outside world, social networks and even the workplace. Complications of immunosuppression and patient mortality have been observed in the initial series. These have highlighted rigorous patient selection as the key predictor of success. The overall early outcomes of the face transplant programme have been generally more positive than many predicted. This initial success is testament to the robust approach of teams. Dissemination of outcomes and ongoing refinement of the process may allow facial transplantation to eventually become a first-line reconstructive option for those with extensive facial disfigurements. Copyright © 2011 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  16. Magnetic separation of encapsulated islet cells labeled with superparamagnetic iron oxide nano particles.

    Science.gov (United States)

    Mettler, Esther; Trenkler, Anja; Feilen, Peter J; Wiegand, Frederik; Fottner, Christian; Ehrhart, Friederike; Zimmermann, Heiko; Hwang, Yong Hwa; Lee, Dong Yun; Fischer, Stefan; Schreiber, Laura M; Weber, Matthias M

    2013-01-01

    Islet cell transplantation is a promising option for the restoration of normal glucose homeostasis in patients with type 1 diabetes. Because graft volume is a crucial issue in islet transplantations for patients with diabetes, we evaluated a new method for increasing functional tissue yield in xenogeneic grafts of encapsulated islets. Islets were labeled with three different superparamagnetic iron oxide nano particles (SPIONs; dextran-coated SPION, siloxane-coated SPION, and heparin-coated SPION). Magnetic separation was performed to separate encapsulated islets from the empty capsules, and cell viability and function were tested. Islets labeled with 1000 μg Fe/ml dextran-coated SPIONs experienced a 69.9% reduction in graft volume, with a 33.2% loss of islet-containing capsules. Islets labeled with 100 μg Fe/ml heparin-coated SPIONs showed a 46.4% reduction in graft volume, with a 4.5% loss of capsules containing islets. No purification could be achieved using siloxane-coated SPIONs due to its toxicity to the primary islets. SPION labeling of islets is useful for transplant purification during islet separation as well as in vivo imaging after transplantation. Furthermore, purification of encapsulated islets can also reduce the volume of the encapsulated islets without impairing their function by removing empty capsules. © 2013 John Wiley & Sons A/S.

  17. Prospective Clinical Testing of Regulatory Dendritic Cells in Organ Transplantation

    OpenAIRE

    Thomson, Angus W.; Zahorchak, Alan F.; Ezzelarab, Mohamed B.; Butterfield, Lisa H.; Lakkis, Fadi G.; Metes, Diana M.

    2016-01-01

    Dendritic cells (DC) are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg) with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering...

  18. ALK5 inhibition maintains islet endothelial cell survival but does not enhance islet graft revascularisation or function.

    Science.gov (United States)

    King, A J F; Clarkin, C E; Austin, A L F; Ajram, L; Dhunna, J K; Jamil, M O; Ditta, S I; Ibrahim, S; Raza, Z; Jones, P M

    2015-01-01

    Islet transplantation is a potential treatment for Type 1 diabetes but long term graft function is suboptimal. The rich supply of intraislet endothelial cells diminishes rapidly after islet isolation and culture, which affects the revascularisation rate of islets after transplantation. The ALK5 pathway inhibits endothelial cell proliferation and thus inhibiting ALK5 is a potential target for improving endothelial cell survival. The aim of the study was to establish whether ALK5 inhibition prevents the loss of intraislet endothelial cells during islet culture and thus improves the functional survival of transplanted islets by enhancing their subsequent revascularisation after implantation. Islets were cultured for 48 h in the absence or presence of 2 different ALK inhibitors: SB-431542 or A-83-01. Their vascular density after culture was analysed using immunohistochemistry. Islets pre-cultured with the ALK5 inhibitors were implanted into streptozotocin-diabetic mice for either 3 or 7 days and blood glucose concentrations were monitored and vascular densities of the grafts were analysed. Islets cultured with ALK5 inhibitors had higher vascular densities than control-cultured islets. Three days after implantation, endothelial cell numbers in islet grafts were minimal, irrespective of treatment during culture. Seven days after implantation, endothelial cells were evident within the islet grafts but there was no difference between control-cultured islets and islets pre-treated with an ALK5 inhibitor. Blood glucose concentrations were no different between the treatment groups. In conclusion, inhibition of ALK5 improved intraislet endothelial cell numbers after islet culture, but this effect was lost in the early post-transplantation period. © Georg Thieme Verlag KG Stuttgart · New York.

  19. In vivo studies on insulin permeability of an immunoisolation device intended for islet transplantation using the microdialysis technique.

    Science.gov (United States)

    Rafael, E; Wernerson, A; Arner, P; Tibell, A

    1999-01-01

    In this study, insulin was injected into Theracyte immunoisolation devices to analyze changes in the permeability of the device over time after implantation. The recovery of insulin was studied after subcutaneous implantation of the devices in rats, using the microdialysis technique. The area under the insulin concentration vs. time curves (AUC) after insulin injection in devices implanted 1 day previously did not differ significantly from the AUC after subcutaneous injection. At 1, 2 and 4 weeks after implantation, the recovery of insulin was significantly reduced, but at 3 months, the AUC was not significantly different from that in the control group. Histological examination showed that the number of vascular profiles within 15 microm of the device were significantly higher at 2, 4 weeks and 3 months after transplantation when compared to numbers at 1 week. The design of the device allows transplantation of cells at a chosen time point after its implantation. Delayed filling of the device would allow neovascularization of the device surface before graft implantation and we suggest that such a schedule might improve function of the encapsulated graft.

  20. Portal Vein Embolization with Radiolabeled Polyvinyl Alcohol Particles in a Swine Model: Hepatic Distribution and Implications for Pancreatic Islet Cell Transplantation

    International Nuclear Information System (INIS)

    Owen, Richard J.; Mercer, John R.; Al-Saif, Faisal; Molinari, Michele; Ashforth, Robert A.; Rajotte, Ray V.; Conner-Spady, Barbara; Shapiro, A. M. James

    2009-01-01

    The distribution of radiolabeled polyvinyl alcohol microspheres (PVAMs) when infused into the portal vein of domestic swine was investigated, with the purpose of assessing implications for pancreatic islet cell transplantation. PVAMs measuring 100-300 μm (Contour SE) and labeled with 99m Tc were infused into the main portal vein of 12 swine, with intermittent portal venous pressure measurements. The infusion catheter was introduced antegradely via direct or indirect cannulation of the portal vein. The liver was subsequently divided into anatomical segments. Radioactivity (decay corrected) was measured for 99m Tc microsphere synthesis, dose preparation, gross organ activities, tissue samples, and blood. Particulate labeling, catheter positioning, and infusion were successful in all cases. The number of particles used was (185,000 ± 24,000) with a volume of 1 ml. Mean portal pressure at 5 min was significantly higher than baseline, but without a significant difference at 15 min. Extrahepatic tissue and serum radioactivity was negligible. A significant difference in number of radioactive particles per gram was detected between segments 6/7 and segments 5/8. Intrasegmental activity was analyzed, and for segments 2/3 a significant difference in the percentage dose per gram across samples was demonstrated (P = 0.001). Effective and stable radiolabeling of PVAMs with 99m Tc-sulfur colloid was demonstrated. Portal venous infusion of 100- to 300-μm particles showed entrapment in the sinusoidal hepatic system with transient portal pressure elevation. Preferential embolization into the right lateral and posterior segments occurs, suggesting that flow dynamics/catheter tip position plays a role in particle distribution.

  1. Overexpression of thioredoxin in islets transduced by a lentiviral vector prolongs graft survival in autoimmune diabetic NOD mice

    Directory of Open Access Journals (Sweden)

    Sytwu Huey-Kang

    2009-08-01

    Full Text Available Abstract Pancreatic islet transplantation is considered an appropriate treatment to achieve insulin independence in type I diabetic patients. However, islet isolation and transplantation-induced oxidative stress and autoimmune-mediated destruction are still the major obstacles to the long-term survival of graft islets in this potential therapy. To protect islet grafts from inflammatory damage and prolong their survival, we transduced islets with an antioxidative gene thioredoxin (TRX using a lentiviral vector before transplantation. We hypothesized that the overexpression of TRX in islets would prolong islet graft survival when transplanted into diabetic non-obese diabetic (NOD mice. Methods Islets were isolated from NOD mice and transduced with lentivirus carrying TRX (Lt-TRX or enhanced green fluorescence protein (Lt-eGFP, respectively. Transduced islets were transplanted under the left kidney capsule of female diabetic NOD mice, and blood glucose concentration was monitored daily after transplantation. The histology of the islet graft was assessed at the end of the study. The protective effect of TRX on islets was investigated. Results The lentiviral vector effectively transduced islets without altering the glucose-stimulating insulin-secretory function of islets. Overexpression of TRX in islets reduced hydrogen peroxide-induced cytotoxicity in vitro. After transplantation into diabetic NOD mice, euglycemia was maintained for significantly longer in Lt-TRX-transduced islets than in Lt-eGFP-transduced islets; the mean graft survival was 18 vs. 6.5 days (n = 9 and 10, respectively, p Conclusion We successfully transduced the TRX gene into islets and demonstrated that these genetically modified grafts are resistant to inflammatory insult and survived longer in diabetic recipients. Our results further support the concept that the reactive oxygen species (ROS scavenger and antiapoptotic functions of TRX are critical to islet survival after

  2. Human islet viability and function is maintained during high density shipment in silicone rubber membrane vessels

    Science.gov (United States)

    Kitzmann, Jennifer P; Pepper, Andrew R; Lopez, Boris G; Pawlick, Rena; Kin, Tatsuya; O’Gorman, Doug; Mueller, Kathryn R; Gruessner, Angelika C; Avgoustiniatos, Efstathios S; Karatzas, Theodore; Szot, Greg L; Posselt, Andrew M; Stock, Peter G; Wilson, John R; Shapiro, AM; Papas, Klearchos K

    2014-01-01

    The shipment of human islets from processing centers to distant laboratories is beneficial for both research and clinical applications. The maintenance of islet viability and function in transit is critically important. Gas-permeable silicone rubber membrane (SRM) vessels reduce the risk of hypoxia-induced death or dysfunction during high-density islet culture or shipment. SRM vessels may offer additional advantages: they are cost-effective (fewer flasks, less labor needed), safer (lower contamination risk), and simpler (culture vessel can also be used for shipment). Human islets(IE) were isolated from two manufacturing centers and shipped in 10cm2 surface area SRM vessels in temperature and pressure controlled containers to a distant center following at least two days of culture (n = 6). Three conditions were examined: low density (LD), high density (HD), and a micro centrifuge tube negative control (NC). LD was designed to mimic the standard culture density for human islet preparations (200 IE/cm2), while HD was designed to have a 20-fold higher tissue density, which would enable the culture of an entire human isolation in 1–3 vessels. Upon receipt, islets were assessed for viability, measured by oxygen consumption rate normalized to DNA content (OCR/DNA), and quantity, measured by DNA, and, when possible, potency and function with dynamic glucose-stimulated insulin secretion (GSIS) measurements and transplants in immunodeficient B6 rag mice. Post-shipment OCR/DNA was not reduced in HD versus LD, and was substantially reduced in the NC condition. HD islets exhibited normal function post-shipment. Based on the data we conclude that entire islet isolations (up to 400,000 IE) may be shipped using a single, larger SRM vessel with no negative effect on viability and ex vivo and in vivo function. PMID:25131090

  3. Adoptive regulatory T cell therapy: challenges in clinical transplantation.

    Science.gov (United States)

    Safinia, Niloufar; Sagoo, Pervinder; Lechler, Robert; Lombardi, Giovanna

    2010-08-01

    The identification and characterisation of regulatory T cells (Tregs) has recently opened up exciting opportunities for Treg cell therapy in transplantation. In this review, we outline the basic biology of Tregs and discuss recent advances and challenges for the identification, isolation and expansion of these cells for cell therapy. Tregs of thymic origin have been shown to be key regulators of immune responses in mice and humans, preventing autoimmunity, graft-versus-host disease and organ graft rejection in the transplantation setting. To date, a variety of different methods to isolate and expand Tregs ex vivo have been advocated. Although promising, relatively few clinical trials of human Treg cell infusion have been initiated. Many key questions about Treg cell therapy still remain and here we provide an in-depth analysis and highlight the challenges and opportunities for immune intervention with Treg-based therapeutics in clinical transplantation.

  4. Pancreatic islet cell tumor

    Science.gov (United States)

    ... cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors; Peptic ulcer - islet cell tumor; Hypoglycemia - islet cell tumor ... stomach acid. Symptoms may include: Abdominal pain Diarrhea ... and small bowel Vomiting blood (occasionally) Glucagonomas make ...

  5. Microencapsulation of Pancreatic Islets for Use in a Bioartificial Pancreas

    Science.gov (United States)

    Opara, Emmanuel C.; McQuilling, John P.; Farney, Alan C.

    2013-01-01

    Islet transplantation is the most exciting treatment option for individuals afflicted with Type 1 diabetes. However, the severe shortage of human pancreas and the need to use risky immunosuppressive drugs to prevent transplant rejection remain two major obstacles for the routine use of islet transplantation in diabetic patients. Successful development of a bioartificial pancreas using the approach of microencapsulation with perm-selective coating of islets with biopolymers for graft immunoisolation holds tremendous promise for diabetic patients because it has great potential to overcome these two barriers. In this chapter, we provide a detailed description of the microencapsulation process. PMID:23494435

  6. Depressive Symptoms, Exercise Capacity, and Clinical Outcomes After Lung Transplantation.

    Science.gov (United States)

    Smith, Patrick J; Byrd, Rebecca; Lusby, Megan; Clausen, Emily; Snyder, Laurie D

    2018-05-01

    Depressive symptoms are common among lung transplant recipients and have been associated with worse clinical outcomes. However, few studies have examined the association between depressive symptoms assessed at multiple time points or behavioral mechanisms by which posttransplant depressive symptoms may confer greater clinical risk. We therefore examined the associations between depressive symptoms, exercise capacity, chronic lung allograft dysfunction (CLAD), and mortality prospectively in a large sample of lung transplant recipients. Between July 2009 and February 2016, 251 lung transplant recipients were assessed before transplantation and again approximately 3 weeks and 3 months after transplant. Depressive symptoms were assessed using the Centers for Epidemiologic Studies of Depression scale. Functional exercise capacity was assessed using the 6-minute walk test. Cox proportional hazards models were used to examine the associations between depressive symptoms, exercise capacity, CLAD, and mortality. During a median (range) follow-up of 4.5 (0.1 to 6.3) years, 53 participants (21%) died. Greater depressive symptoms (hazard ratio [HR] = 1.39 [95% CI = 1.05 to 1.84], p = .021) and poorer exercise capacity (HR = 0.58 [95% CI = 0.38 to 0.90], p = .021) assessed 3 months after transplant were both independently associated with mortality. Although greater depressive symptoms were associated with lower exercise capacity (β = -0.14, p = .039), exercise capacity did not mediate the association between depressive symptoms and mortality. In secondary analyses, depressive symptoms were independently predictive of CLAD (HR = 1.29 [95% CI = 1.01 to 1.65], p = .045) and the composite outcome of CLAD and mortality in a clustered event model (HR = 1.30 [1.09 to 1.56], p = .005). Depressive symptoms are associated with mortality and CLAD after lung transplantation, independent of exercise capacity.

  7. Clinical trials for stem cell transplantation: when are they needed?

    Science.gov (United States)

    Van Pham, Phuc

    2016-04-27

    In recent years, both stem cell research and the clinical application of these promising cells have increased rapidly. About 1000 clinical trials using stem cells have to date been performed globally. More importantly, more than 10 stem cell-based products have been approved in some countries. With the rapid growth of stem cell applications, some countries have used clinical trials as a tool to diminish the rate of clinical stem cell applications. However, the point at which stem cell clinical trials are essential remains unclear. This commentary discusses when stem cell clinical trials are essential for stem cell transplantation therapies.

  8. Face Transplantation: On the Verge of Becoming Clinical Routine?

    Directory of Open Access Journals (Sweden)

    Ralf Smeets

    2014-01-01

    Full Text Available Introduction. Face transplantation (FT is an innovative achievement of modern reconstructive surgery and is on the verge of becoming a common surgical opportunity. This review article was compiled to provide an update on this surgical field, especially regarding clinical outcomes, benefits, and complications implied. Methods. We performed an extensive research on all English-language Medline articles, case reports, and reviews published online until September 15, 2013. Used search terms were “face transplantation,” “face transplant,” “facial transplantation,” “facial transplant,” “face allograft,” and “facial allograft.” Results. To date 27 FTs have been performed worldwide. 19 of these cases have been published in the Medline database. Long-term follow-up reports of FT cases are rare. Three deaths associated with the procedure have occurred to date. The clinical outcomes of FT are satisfying. Reinnervation of sensation has been faster than motor recovery. Extensive functional improvements have been observed. Due to strict immunosuppression protocols, no case of hyperacute or chronic rejection and no graft-versus-host disease have occurred to date. Conclusions. As studies on long-term outcomes are missing, particularly regarding immunosuppression-related complications, FT will stay experimental for the next years. Nevertheless, for a small group of patients, FT already is a feasible reconstructive option.

  9. Prospective Clinical Testing of Regulatory Dendritic Cells in Organ Transplantation.

    Science.gov (United States)

    Thomson, Angus W; Zahorchak, Alan F; Ezzelarab, Mohamed B; Butterfield, Lisa H; Lakkis, Fadi G; Metes, Diana M

    2016-01-01

    Dendritic cells (DC) are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg) with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering the incidence and severity of rejection and reducing patients' dependence on anti-rejection drugs. Generation of donor- or recipient-derived DCreg that suppress T cell responses and prolong transplant survival in rodents or non-human primates has been well-described. Recently, good manufacturing practice (GMP)-grade DCreg have been produced at our Institution for prospective use in human organ transplantation. We briefly review experience of regulatory immune therapy in organ transplantation and describe our experience generating and characterizing human monocyte-derived DCreg. We propose a phase I/II safety study in which the influence of donor-derived DCreg combined with conventional immunosuppression on subclinical and clinical rejection and host alloimmune responses will be examined in detail.

  10. Physical rehabilitation for lung transplant candidates and recipients: An evidence-informed clinical approach

    Science.gov (United States)

    Wickerson, Lisa; Rozenberg, Dmitry; Janaudis-Ferreira, Tania; Deliva, Robin; Lo, Vincent; Beauchamp, Gary; Helm, Denise; Gottesman, Chaya; Mendes, Polyana; Vieira, Luciana; Herridge, Margaret; Singer, Lianne G; Mathur, Sunita

    2016-01-01

    Physical rehabilitation of lung transplant candidates and recipients plays an important in optimizing physical function prior to transplant and facilitating recovery of function post-transplant. As medical and surgical interventions in lung transplantation have evolved over time, there has been a demographic shift of individuals undergoing lung transplantation including older individuals, those with multiple co-morbidites, and candidates with respiratory failure requiring bridging to transplantation. These changes have an impact on the rehabilitation needs of lung transplant candidates and recipients. This review provides a practical approach to rehabilitation based on research and clinical practice at our transplant centre. It focuses on functional assessment and exercise prescription during an uncomplicated and complicated clinical course in the pre-transplant, early and late post-transplant periods. The target audience includes clinicians involved in pre- and post-transplant patient care and rehabilitation researchers. PMID:27683630

  11. Immune responses to an encapsulated allogeneic islet β-cell line in diabetic NOD mice

    International Nuclear Information System (INIS)

    Black, Sasha P.; Constantinidis, Ioannis; Cui, Hong; Tucker-Burden, Carol; Weber, Collin J.; Safley, Susan A.

    2006-01-01

    Our goal is to develop effective islet grafts for treating type 1 diabetes. Since human islets are scarce, we evaluated the efficacy of a microencapsulated insulin-secreting conditionally transformed allogeneic β-cell line (βTC-tet) in non-obese diabetic mice treated with tetracycline to inhibit cell growth. Relatively low serum levels of tetracycline controlled proliferation of βTC-tet cells without inhibiting effective control of hyperglycemia in recipients. There was no significant host cellular reaction to the allografts or host cell adherence to microcapsules, and host cytokine levels were similar to those of sham-operated controls. We conclude that encapsulated allogeneic β-cell lines may be clinically relevant, because they effectively restore euglycemia and do not elicit a strong cellular immune response following transplantation. To our knowledge, this is First extensive characterization of the kinetics of host cellular and cytokine responses to an encapsulated islet cell line in an animal model of type 1 diabetes

  12. Clinical factors influencing participation in society after successful kidney transplantation

    NARCIS (Netherlands)

    van der Mei, S.F.; Groothoff, J.W.; van Sonderen, E.L.P.; van den Heuvel, W.J.A.; de Jong, P.E.; van Son, W.J.

    2006-01-01

    Background. Little information is available on the degree of actual social functioning after successful kidney transplantation. Moreover, information on factors that influence participation in social activities is scarce. The aim of this study was to examine the influence of clinical factors on

  13. Islet grafting and imaging in a bioengineered intramuscular space†

    Science.gov (United States)

    Witkowski, Piotr; Sondermeijer, Hugo; Hardy, Mark A.; Woodland, David C.; Lee, Keagan; Bhagat, Govind; Witkowski, Kajetan; See, Fiona; Rana, Abbas; Maffei, Antonella; Itescu, Silviu; Harris, Paul E.

    2011-01-01

    Background Since the hepatic portal system may not be the optimal site for islet transplantation, several extrahepatic sites have been studied. Here we examine an intramuscular transplantation site, bioengineered to better support islet neovascularization, engraftment, and survival, and demonstrate that at this novel site, grafted beta cell mass may be quantitated in a real time non-invasive manner by PET imaging. Methods Streptozotocin induced rats were pretreated intramuscularly with a biocompatible angiogenic scaffold received syngeneic islet transplants 2 weeks later. The recipients were monitored serially by blood glucose and glucose tolerance measurements and by PET imaging of the transplant site with [11C] dihydrotetrabenazine. Parallel histopathologic evaluation of the grafts was done using insulin staining and evaluation of microvasularity. Results Reversal of hyperglycemia by islet transplantation was most successful in recipients pretreated with bioscaffolds containing angiogenic factors as compared to those who received no bioscaffolds or bioscaffolds not treated with angiogenic factors. PET imaging with [11C] dihydrotetrabenazine, insulin staining and microvascular density patterns were consistent with islet survival, increased levels of angiogenesis, and with reversal of hyperglycemia. Conclusions Induction of increased neovascularization at an intramuscular site significantly improves islet transplant engraftment and survival compared to controls. The use of a non hepatic transplant site may avoid intrahepatic complications and permit the use of PET imaging to measure and follow transplanted beta-cell mass in real time. These findings have important implications for effective islet implantation outside of the liver, and offer promising possibilities for improving islet survival, monitoring, and even prevention of islet loss. PMID:19898201

  14. Prolonged survival of isolated rat islet allografts pre-irradiated with X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Toshihisa; Note, Masayuki; Nakagawara, Gizo (Fukui Medical School, Matsuoka (Japan)); Kojima, Yasuhiko

    1994-04-01

    Prior to transplantation of islets, pre-incubation, or pre-irradiation may suppress the immunogenicity of islet cells without suppressing islet function. In the presently described experiments we investigated the use of X-ray irradiation prior to transplantation to reduce islet immunogenicity. To determine whether or not the islet function was reduced after irradiation, ACI rat islets were transplanted into the subrenal capsules of isogeneic rats which had been diabetic and examined the blood glucose level over a period of 40 days. The results indicated that irradiation injury was dose-dependent and that islets irradiated with over 80 Gy lost their function. Next, allogeneic transplantation was performed using the model of ACI rats to Lewis rats without the use of any immunosuppressive agent. Non-irradiated islets were rejected within 7 days. However 20 Gy or 40 Gy irradiated islets prolonged survival (18.7[+-]5.8 days (n=6) and 26.7[+-]10.0 days (n=6), respectively). To determine the basis for this effect, MHC expression of islets was examined by the immunoperoxidase technique. Immunohistologic studies showed that 40 Gy-irradiated islets were depleted of Class II antigen positive cells while Class I antigen expression was unchanged. These results suggest that the prolongation of islets survival by X-ray irradiation may possibly be due to, in part, the depletion of donor Class II antigen positive cells. (author).

  15. Repurposing Lesogaberan to Promote Human Islet Cell Survival and β-Cell Replication

    Directory of Open Access Journals (Sweden)

    Jide Tian

    2017-01-01

    Full Text Available The activation of β-cell’s A- and B-type gamma-aminobutyric acid receptors (GABAA-Rs and GABAB-Rs can promote their survival and replication, and the activation of α-cell GABAA-Rs promotes their conversion into β-cells. However, GABA and the most clinically applicable GABA-R ligands may be suboptimal for the long-term treatment of diabetes due to their pharmacological properties or potential side-effects on the central nervous system (CNS. Lesogaberan (AZD3355 is a peripherally restricted high-affinity GABAB-R-specific agonist, originally developed for the treatment of gastroesophageal reflux disease (GERD that appears to be safe for human use. This study tested the hypothesis that lesogaberan could be repurposed to promote human islet cell survival and β-cell replication. Treatment with lesogaberan significantly enhanced replication of human islet cells in vitro, which was abrogated by a GABAB-R antagonist. Immunohistochemical analysis of human islets that were grafted into immune-deficient mice revealed that oral treatment with lesogaberan promoted human β-cell replication and islet cell survival in vivo as effectively as GABA (which activates both GABAA-Rs and GABAB-Rs, perhaps because of its more favorable pharmacokinetics. Lesogaberan may be a promising drug candidate for clinical studies of diabetes intervention and islet transplantation.

  16. First update of the International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--Chapter 5: recipient monitoring and response plan for preventing disease transmission.

    Science.gov (United States)

    Denner, Joachim; Tönjes, Ralf R; Takeuchi, Yasu; Fishman, Jay; Scobie, Linda

    2016-01-01

    Xenotransplantation of porcine cells, tissues, and organs may be associated with the transmission of porcine microorganisms to the human recipient. A previous, 2009, version of this consensus statement focused on strategies to prevent transmission of porcine endogenous retroviruses (PERVs). This version addresses potential transmission of all porcine microorganisms including monitoring of the recipient and provides suggested approaches to the monitoring and prevention of disease transmission. Prior analyses assumed that most microorganisms other than the endogenous retroviruses could be eliminated from donor animals under appropriate conditions which have been called "designated pathogen-free" (DPF) source animal production. PERVs integrated as proviruses in the genome of all pigs cannot be eliminated in that manner and represent a unique risk. Certain microorganisms are by nature difficult to eliminate even under DPF conditions; any such clinically relevant microorganisms should be included in pig screening programs. With the use of porcine islets in clinical trials, special consideration has to be given to the presence of microorganisms in the isolated islet tissue to be used and also to the potential use of encapsulation. It is proposed that microorganisms absent in the donor animals by sensitive microbiological examination do not need to be monitored in the transplant recipient; this will reduce costs and screening requirements. Valid detection assays for donor and manufacturing-derived microorganisms must be established. Special consideration is needed to preempt potential unknown pathogens which may pose a risk to the recipient. This statement summarizes the main achievements in the field since 2009 and focus on issues and solutions with microorganisms other than PERV. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Fibromyalgia and its clinical relevance in renal transplant recipients.

    Science.gov (United States)

    Erkmen Uyar, M; Sezer, S; Bal, Z; Guliyev, O; Tutal, E; Genctoy, G; Kulah, E; Ozdemir Acar, N; Haberal, M

    2015-05-01

    Recent evidence suggests that fibromyalgia syndrome (FS) is associated with inflammation and endothelial dysfunction. Our aim was to determine the prevalence of FS in renal transplant recipients and to identify possible links between FS and clinical and laboratory parameters. Ninety-nine kidney transplant recipients with normal graft functions (37.15 ± 10.83 years old, 67 male) were enrolled in the study. All subjects completed the Fibromyalgia Impact Questionnaire (FIQ). The biochemical and clinical parameters in the 1st post-transplantation year were retrospectively recorded. Cardiovascular parameters, including body composition analyses (Tanita), ambulatory blood pressure monitoring data, and pulse-wave velocity, were cross-sectionally analyzed. Mean FIQ score for the whole group was 21.4 ± 14.7. Eight patients had FIQ score >50, and these patients had significantly higher left ventricular mass index than patients with lower FIQ score (P = .048). Patients were divided according to their physical impairment score (PIS): PIS ≥5 (n = 50) and PIS FIQ (7.6% vs 9.4%; P = .0001) than in other patients. FS in renal transplant recipients was strongly associated with hypertension, arterial stiffness, obesity, and renal allograft dysfunction. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. A Practical Guide to Rodent Islet Isolation and Assessment

    Directory of Open Access Journals (Sweden)

    Carter Jeffrey D

    2009-12-01

    Full Text Available Abstract Pancreatic islets of Langerhans secrete hormones that are vital to the regulation of blood glucose and are, therefore, a key focus of diabetes research. Purifying viable and functional islets from the pancreas for study is an intricate process. This review highlights the key elements involved with mouse and rat islet isolation, including choices of collagenase, the collagenase digestion process, purification of islets using a density gradient, and islet culture conditions. In addition, this paper reviews commonly used techniques for assessing islet viability and function, including visual assessment, fluorescent markers of cell death, glucose-stimulated insulin secretion, and intracellular calcium measurements. A detailed protocol is also included that describes a common method for rodent islet isolation that our laboratory uses to obtain viable and functional mouse islets for in vitro study of islet function, beta-cell physiology, and in vivo rodent islet transplantation. The purpose of this review is to serve as a resource and foundation for successfully procuring and purifying high-quality islets for research purposes.

  19. A preclinical evaluation of alternative site for islet allotransplantation.

    Directory of Open Access Journals (Sweden)

    Chengshi Wang

    Full Text Available The bone marrow cavity (BMC has recently been identified as an alternative site to the liver for islet transplantation. This study aimed to compare the BMC with the liver as an islet allotransplantation site in diabetic monkeys. Diabetes was induced in Rhesus monkeys using streptozocin, and the monkeys were then divided into the following three groups: Group1 (islets transplanted in the liver with immunosuppressant, Group 2 (islets transplanted in the tibial BMC, and Group 3 (islets transplanted in the tibial BMC with immunosuppressant. The C-peptide and blood glucose levels were preoperatively measured. An intravenous glucose tolerance test (IVGTT was conducted to assess graft function, and complete blood cell counts were performed to assess cell population changes. Cytokine expression was measured using an enzyme-linked immune sorbent assay (ELISA and MILLIPLEX. Five monkeys in Group 3 exhibited a significantly increased insulin-independent time compared with the other groups (Group 1: 78.2 ± 19.0 days; Group 2: 58.8 ± 17.0 days; Group 3: 189.6 ± 26.2 days and demonstrated increases in plasma C-peptide 4 months after transplantation. The infusion procedure was not associated with adverse effects. Functional islets in the BMC were observed 225 days after transplantation using the dithizone (DTZ and insulin/glucagon stains. Our results showed that allogeneic islets transplanted in the BMC of diabetic Rhesus monkeys remained alive and functional for a longer time than those transplanted in the liver. This study was the first successful demonstration of allogeneic islet engraftment in the BMC of non-human primates (NHPs.

  20. Development of a renal transplant clinical pathway: one hospital's journey.

    Science.gov (United States)

    Darrikhuma, I M

    1999-05-01

    Mounting pressures to resolve multiple challenges related to quality, cost, and access in a resource-driven, customer-focused health care environment have compelled clinicians to develop innovative strategies to provide cost-effective, state-of-the-art care. Targeted patient groups include those associated with high cost, high volume, or high resource use. Patients undergoing renal transplantation fall into one or more of these categories. Recently, the management of patients with end-stage renal disease (ESRD) has come under national focus, as evidenced by the fact that Health Care Financing Administration (HCFA) has commissioned an ESRD managed care demonstration project. The purpose of this article is to describe how one case management tool--the clinical pathway--can be used to decrease costs and improve outcomes associated with renal transplantation. This discussion will include a review of the origins and components of clinical pathways and a description of how one institution developed, implemented, evaluated, and refined a renal transplantation clinical pathway.

  1. Genetically Engineered Islets and Alternative Sources of Insulin-Producing Cells for Treating Autoimmune Diabetes: Quo Vadis?

    Directory of Open Access Journals (Sweden)

    Feng-Cheng Chou

    2012-01-01

    Full Text Available Islet transplantation is a promising therapy for patients with type 1 diabetes that can provide moment-to-moment metabolic control of glucose and allow them to achieve insulin independence. However, two major problems need to be overcome: (1 detrimental immune responses, including inflammation induced by the islet isolation/transplantation procedure, recurrence autoimmunity, and allorejection, can cause graft loss and (2 inadequate numbers of organ donors. Several gene therapy approaches and pharmaceutical treatments have been demonstrated to prolong the survival of pancreatic islet grafts in animal models; however, the clinical applications need to be investigated further. In addition, for an alternative source of pancreatic β-cell replacement therapy, the ex vivo generation of insulin-secreting cells from diverse origins of stem/progenitor cells has become an attractive option in regenerative medicine. This paper focuses on the genetic manipulation of islets during transplantation therapy and summarizes current strategies to obtain functional insulin-secreting cells from stem/progenitor cells.

  2. Successful suppression of the early rejection of pig islets in monkeys

    NARCIS (Netherlands)

    Rijkelijkhuizen, JKRA; Bouwman, E; van der Burg, MPM; Ringers, J; Ossevoort, MA; Kuhn, EM; Frost, P; Jonker, M

    2000-01-01

    Primary nonfunction (PNF) is seen very frequently after xenogeneic transplantation of islets of Langerhans. In a pig-to-rat model we recently observed that no PNF occurs when the islets are kept in culture at 37 degreesC fur 1-2 weeks prior to transplantation. In order to investigate the rejection

  3. Prolongation of rat islet allograft survival by direct ultraviolet irradiation of the graft

    International Nuclear Information System (INIS)

    Lau, H.; Reemtsma, K.; Hardy, M.A.

    1984-01-01

    Ultraviolet irradiation of rat dendritic cells completely abrogated their allostimulatory capacity in a mixed lymphocyte reaction. Rat islets of Langerhans similarly irradiated remained hormonally functional when transplanted into syngeneic diabetic rats. Allogeneic transplantation across a major histocompatibility barrier of islets initially treated in vitro with ultraviolet irradiation resulted in prolonged allograft survival without the use of any immunosuppressive agents

  4. Label-Free Detection of Insulin and Glucagon within Human Islets of Langerhans Using Raman Spectroscopy

    NARCIS (Netherlands)

    Hilderink, J.; Otto, Cornelis; Slump, Cornelis H.; Lenferink, Aufrid T.M.; Engelse, M.A.; van Blitterswijk, Clemens; de Koning, E.J.P.; Karperien, Hermanus Bernardus Johannes; van Apeldoorn, Aart A.

    2013-01-01

    Intrahepatic transplantation of donor islets of Langerhans is a promising therapy for patients with type 1 diabetes. It is of critical importance to accurately monitor islet quality before transplantation, which is currently done by standard histological methods that are performed off-line and

  5. Photochemical (PUVA) treatment of isolated rat islets

    International Nuclear Information System (INIS)

    Schmidt, S.; Wilke, B.; Kloeting, I.

    1984-01-01

    Isolated rat islets were irradiated with long-wave ultraviolet light alone or in combination with the photosensitizer 8-methoxypsoralen. The influence on specific beta cell functions was determined with the aim to find out experimental conditions which allow the use of such islets for transplantation. Short-term effects: Ultraviolet light affected [ 3 H]leucine incorporation into (pro)insulin (5 J/cm 2 : 53.8 %, 10 J/cm 2 : 41.0 % of the controls) and insulin release was slightly reduced. 8-methoxypsoralen enhanced the irradiation effect. Long-term effects: A restoration of irradiation-affected beta cell function was detected after 5 days of culture unless the dose exceeded 2 J/cm 2 (0.1 μM 8-methoxypsoralen) or 1 J/cm 2 (1 μM 8-methoxypsoralen). After functional restoration islets were used for transplantation experiments. (author)

  6. Photochemical (PUVA) treatment of isolated rat islets

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, S; Wilke, B; Kloeting, I [Zentralinstitut fuer Diabetes, Karlsburg (German Democratic Republic)

    1984-05-01

    Isolated rat islets were irradiated with long-wave ultraviolet light alone or in combination with the photosensitizer 8-methoxypsoralen. The influence on specific beta cell functions was determined with the aim to find out experimental conditions which allow the use of such islets for transplantation. Short-term effects: Ultraviolet light affected (/sup 3/H)leucine incorporation into (pro)insulin (5 J/cm/sup 2/ : 53.8 %, 10 J/cm/sup 2/ : 41.0 % of the controls) and insulin release was slightly reduced. 8-methoxypsoralen enhanced the irradiation effect. Long-term effects: A restoration of irradiation-affected beta cell function was detected after 5 days of culture unless the dose exceeded 2 J/cm/sup 2/ (0.1 ..mu..M 8-methoxypsoralen) or 1 J/cm/sup 2/ (1 ..mu..M 8-methoxypsoralen). After functional restoration islets were used for transplantation experiments.

  7. The dissociation of tumor-induced weight loss from hypoglycemia in a transplantable pluripotent rat islet tumor results in the segregation of stable alpha- and beta-cell tumor phenotypes

    DEFF Research Database (Denmark)

    Madsen, O D; Karlsen, C; Nielsen, E

    1993-01-01

    in NEDH rats resulted in stable hypoglycemic insulinoma tumor lines, such as MSL-G2-IN. Occasionally, hypoglycemia as well as severe weight loss were observed in the early tumor passages of MSL-G and the subclone, NHI-5B, which carry the transfected neomycin and human insulin genes as unique clonal...... markers. By selective transplantation, it was possible to segregate stable anorectic normoglycemic tumor lines, MSL-G-AN and NHI-5B-AN, from both clones. These tumors cause an abrupt onset of anorexia when they reach a size of 400-500 mg (loss parallels...... a common clonal origin of pluripotent MSL cells, thus supporting the existence of a cell lineage relationship between islet alpha- and beta-cell during ontogeny; and 2) that our glucagonomas release an anorexigenic substance(s) of unknown nature that causes a severe weight loss comparable to that reported...

  8. Clinical outcome of combined conjunctival autograft transplantation and amniotic membrane transplantation in pterygium surgery

    Science.gov (United States)

    Malla, Tejsu; Jiang, Jing; Hu, Kai

    2018-01-01

    AIM To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques: combined conjunctival autograft and overlay amniotic membrane transplantation (CAT with AMT), conjunctival autograft transplantation (CAT) alone and amniotic membrane transplantation (AMT) alone. METHODS In this retrospective study, 142 eyes of 142 pterygium patients (104 primary, 38 recurrent) who underwent CAT (group A), AMT (group B) or CAT with AMT (group C) respectively following surgical excision were reviewed and compared based on the recurrences and post-operative complications. RESULTS The number of recurrence post-surgery were 17 (9 from primary, 8 from recurrent; the same description below), 18 (10, 8) and 2 (1, 1) in groups A, B, and C respectively; dry eyes were 22 (16, 6), 27 (18, 9) and 7 (3, 4); conjunctival inflammations were 30 (17, 13), 27 (16, 11) and 11 (6, 5). Patients in group C (either primary or recurrent or both) mainly showed significantly better results than those in group A or B (P<0.05) regarding above-mentioned clinical effects. CONCLUSION Combined CAT and overly AMT have significantly lower rates of recurrence and postoperative complications for primary and recurrent pterygium surgery than CAT or AMT alone. PMID:29600172

  9. Clinical outcome of combined conjunctival autograft transplantation and amniotic membrane transplantation in pterygium surgery

    Directory of Open Access Journals (Sweden)

    Tejsu Malla

    2018-03-01

    Full Text Available AIM: To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques: combined conjunctival autograft and overlay amniotic membrane transplantation (CAT with AMT, conjunctival autograft transplantation (CAT alone and amniotic membrane transplantation (AMT alone. METHODS: In this retrospective study, 142 eyes of 142 pterygium patients (104 primary, 38 recurrent who underwent CAT (group A, AMT (group B or CAT with AMT (group C respectively following surgical excision were reviewed and compared based on the recurrences and post-operative complications. RESULTS: The number of recurrence post-surgery were 17 (9 from primary, 8 from recurrent; the same description below, 18 (10, 8 and 2 (1, 1 in groups A, B, and C respectively; dry eyes were 22 (16, 6, 27 (18, 9 and 7 (3, 4; conjunctival inflammations were 30 (17, 13, 27 (16, 11 and 11 (6, 5. Patients in group C (either primary or recurrent or both mainly showed significantly better results than those in group A or B (P<0.05 regarding above-mentioned clinical effects. CONCLUSION: Combined CAT and overly AMT have significantly lower rates of recurrence and postoperative complications for primary and recurrent pterygium surgery than CAT or AMT alone.

  10. Adipose stem cells from chronic pancreatitis patients improve mouse and human islet survival and function.

    Science.gov (United States)

    Song, Lili; Sun, Zhen; Kim, Do-Sung; Gou, Wenyu; Strange, Charlie; Dong, Huansheng; Cui, Wanxing; Gilkeson, Gary; Morgan, Katherine A; Adams, David B; Wang, Hongjun

    2017-08-30

    Chronic pancreatitis has surgical options including total pancreatectomy to control pain. To avoid surgical diabetes, the explanted pancreas can have islets harvested and transplanted. Immediately following total pancreatectomy with islet autotransplantation (TP-IAT), many islet cells die due to isolation and transplantation stresses. The percentage of patients remaining insulin free after TP-IAT is therefore low. We determined whether cotransplantation of adipose-derived mesenchymal stem cells (ASCs) from chronic pancreatitis patients (CP-ASCs) would protect islets after transplantation. In a marginal mass islet transplantation model, islets from C57BL/6 mice were cotransplanted with CP-ASCs into syngeneic streptozotocin-treated diabetic mice. Treatment response was defined by the percentage of recipients reaching normoglycemia, and by the area under the curve for glucose and c-peptide in a glucose tolerance test. Macrophage infiltration, β-cell apoptosis, and islet graft vasculature were measured in transplanted islet grafts by immunohistochemistry. mRNA expression profiling of 84 apoptosis-related genes in islet grafts transplanted alone or with CP-ASCs was measured by the RT 2 Profiler™ Apoptosis PCR Array. The impact of insulin-like growth factor-1 (IGF-1) on islet apoptosis was determined in islets stimulated with cytokines (IL-1β and IFN-γ) in the presence and absence of CP-ASC conditioned medium. CP-ASC-treated mice were more often normoglycemic compared to mice receiving islets alone. ASC cotransplantation reduced macrophage infiltration, β-cell death, suppressed expression of TNF-α and Bcl-2 modifying factor (BMF), and upregulated expressions of IGF-1 and TNF Receptor Superfamily Member 11b (TNFRSF11B) in islet grafts. Islets cultured in conditioned medium from CP-ASCs showed reduced cell death. This protective effect was diminished when IGF-1 was blocked in the conditioned medium by the anti-IGF-1 antibody. Cotransplantation of islets with ASCs

  11. [Post-transplant recurrence of glomerulonephritis: a complex clinical case].

    Science.gov (United States)

    Bonucchi, Decenzio; Leonelli, Marco; Damiano, Francesca; Granito, Maria; Ghiandai, Giulia; De Amicis, Sara; Americo, Claudio; Ligabue, Giulia; Albertazzi, Vittorio; Cappelli, Gianni

    2010-01-01

    Lupus nephritis (LN) seldom recurs in a grafted kidney. By contrast, primary membranoproliferative glomerulonephritis (MPGN), which has been included, along with hemolytic uremic syndrome and age-related maculopathy, among the complement dysregulation diseases, has a high recurrence rate and is considered a contraindication to living-donor kidney transplant because of the poor prognosis. We report the case of a young girl with LN-related chronic renal failure who underwent a living donor transplant from her mother. After four months she had a recurrence that did not match the criteria for LN. Graft biopsies and revision of the clinical course pointed to type II MPGN on the basis of a lack of ARA criteria, persistent isolated low C3 levels, and response to plasma therapy. If confirmed by genetic analysis, the patient might benefit from treatment with the monoclonal antibody against the C5-C9 complex, eculizumab.

  12. Clinical analysis of polycythemia after kidney transplantation: 65 cases report

    Directory of Open Access Journals (Sweden)

    Chao ZHANG

    2014-01-01

    Full Text Available Objective To analyze the clinical characteristics, risk factors, treatment and turnover of the polycythemia after kidney transplantation. Methods The clinical data of 329 renal transplantation recipients who had undergone kidney transplantation in the Transplant Center of 309 Hospital of PLA from Jan. 2008 to Jan. 2012, were retrospectively analyzed. Posttransplant erythrocytosis (PTE was found in 65 recipients (PTE group, and no PTE was found in 264 recipients (control group. The pre- and post-operative parameters, the therapeutic effect of different treatments, and outcomes were compared between PTE group and control group. Results Patients in PTE group were younger, and the ratio of males was higher compared with that of control group (P0.05. PTE incidence was higher in recipients (24.3%, n=185 who had accepted cyclosporine than those recipients (13.9%, n=144 who had accepted tacrolimus, and the difference was statistically significant (P0.05, but the relapse rate and the embolism rate due to concurrent thrombus were lower in conservative treatment group than in venesection group with statistical significance (P<0.05. Conclusion PTE is more common in male recipients with good graft function. Smoking, high nutritional status, concomitant hypertension and diabetes are the risk factors for PTE. Administration of tacrolimus may reduce the PTE incidence. Compared with venesection treatment, conservative treatment may be more effective in treating PTE with lower relapse rate and embolism rate due to concurrent thrombus. DOI: 10.11855/j.issn.0577-7402.2013.12.10

  13. Regional differences in islet distribution in the human pancreas--preferential beta-cell loss in the head region in patients with type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Xiaojun Wang

    Full Text Available While regional heterogeneity in islet distribution has been well studied in rodents, less is known about human pancreatic histology. To fill gaps in our understanding, regional differences in the adult human pancreas were quantitatively analyzed including the pathogenesis of type 2 diabetes (T2D. Cadaveric pancreas specimens were collected from the head, body and tail regions of each donor, including subjects with no history of diabetes or pancreatic diseases (n = 23 as well as patients with T2D (n = 12. The study further included individuals from whom islets were isolated (n = 7 to study islet yield and function in a clinical setting of islet transplantation. The whole pancreatic sections were examined using an innovative large-scale image capture and unbiased detailed quantitative analyses of the characteristics of islets from each individual (architecture, size, shape and distribution. Islet distribution/density is similar between the head and body regions, but is >2-fold higher in the tail region. In contrast to rodents, islet cellular composition and architecture were similar throughout the pancreas and there was no difference in glucose-stimulated insulin secretion in islets isolated from different regions of the pancreas. Further studies revealed preferential loss of large islets in the head region in patients with T2D. The present study has demonstrated distinct characteristics of the human pancreas, which should provide a baseline for the future studies integrating existing research in the field and helping to advance bi-directional research between humans and preclinical models.

  14. Rat pancreatic islet size standardization by the "hanging drop" technique.

    Science.gov (United States)

    Cavallari, G; Zuellig, R A; Lehmann, R; Weber, M; Moritz, W

    2007-01-01

    Rejection and hypoxia are the main factors that limit islet engraftment in the recipient liver in the immediate posttransplant period. Recently authors have reported a negative relationship of graft function and islet size, concluding that small islets are superior to large islets. Islets can be dissociated into single cells and reaggregated into so called "pseudoislets," which are functionally equivalent to intact islets but exhibit reduced immunogenicity. The aim of our study was develop a technique that enabled one to obtain pseudoislets of defined, preferably small, dimensions. Islets were harvested from Lewis rats by the collagenase digestion procedure. After purification, the isolated islets were dissociated into single cells by trypsin digestion. Fractions with different cell numbers were seeded into single drops onto cell culture dishes, which were inverted and incubated for 5 to 8 days under cell culture conditions. Newly formed pseudoislets were analyzed for dimension, morphology, and cellular composition. The volume of reaggregated pseudoislets strongly correlated with the cell number (r(2) = .995). The average diameter of a 250-cell aggregate was 95 +/- 8 microm (mean +/- SD) compared with 122 +/- 46 microm of freshly isolated islets. Islet cell loss may be minimized by performing reaggregation in the presence of medium glucose (11 mmol/L) and the GLP-1 analogue Exendin-4. Morphology, cellular composition, and architecture of reaggregated islets were comparable to intact islets. The "hanging drop" culture method allowed us to obtain pseudoislets of standardized size and regular shape, which did not differ from intact islets in terms of cellular composition or architecture. Further investigations are required to minimize cell loss and test in vivo function of transplanted pseudoislets.

  15. Human Islet Amyloid Polypeptide

    DEFF Research Database (Denmark)

    Kosicka, Iga

    2014-01-01

    Diabetes mellitus type II is a metabolic disease affecting millions of people worldwide. The disease is associated with occurence of insoluble, fibrillar, protein aggregates in islets of Langerhans in the pancreas - islet amyloid. The main constituent of these protein fibers is the human islet...... of diabetes type II, while revealing the structure(s) of islet amyloid fibrils is necessary for potential design of therapeutic agents....

  16. Preservation of beta cell function in adult human pancreatic islets for several months in vitro

    DEFF Research Database (Denmark)

    Brunstedt, J; Andersson, A; Frimodt-Møller, C

    1979-01-01

    Islets of Langerhans were isolated from four human kidney donors, aged 16 to 21 years by the collagenase method described for isolation of rodent islets. So far the human islets have been kept in tissue culture, without attachment, in medium RPMI 1640 supplemented with 10% calf serum for more tha...... technique presents a valuable tool for studying chronic effects of metabolites and hormones on islet function, as well as for islet storage prior to transplantation into humans.......Islets of Langerhans were isolated from four human kidney donors, aged 16 to 21 years by the collagenase method described for isolation of rodent islets. So far the human islets have been kept in tissue culture, without attachment, in medium RPMI 1640 supplemented with 10% calf serum for more than...

  17. Autologous Mesenchymal Stem Cell and Islet Cotransplantation: Safety and Efficacy.

    Science.gov (United States)

    Wang, Hongjun; Strange, Charlie; Nietert, Paul J; Wang, Jingjing; Turnbull, Taylor L; Cloud, Colleen; Owczarski, Stefanie; Shuford, Betsy; Duke, Tara; Gilkeson, Gary; Luttrell, Louis; Hermayer, Kathie; Fernandes, Jyotika; Adams, David B; Morgan, Katherine A

    2018-01-01

    Islet engraftment after transplantation is impaired by high rates of islet/β cell death caused by cellular stressors and poor graft vascularization. We studied whether cotransplantation of ex vivo expanded autologous bone marrow-derived mesenchymal stem cells (MSCs) with islets is safe and beneficial in chronic pancreatitis patients undergoing total pancreatectomy with islet autotransplantation. MSCs were harvested from the bone marrow of three islet autotransplantation patients and expanded at our current Good Manufacturing Practices (cGMP) facility. On the day of islet transplantation, an average dose of 20.0 ± 2.6 ×10 6 MSCs was infused with islets via the portal vein. Adverse events and glycemic control at baseline, 6, and 12 months after transplantation were compared with data from 101 historical control patients. No adverse events directly related to the MSC infusions were observed. MSC patients required lower amounts of insulin during the peritransplantation period (p = .02 vs. controls) and had lower 12-month fasting blood glucose levels (p = .02 vs. controls), smaller C-peptide declines over 6 months (p = .01 vs. controls), and better quality of life compared with controls. In conclusion, our pilot study demonstrates that autologous MSC and islet cotransplantation may be a safe and potential strategy to improve islet engraftment after transplantation. (Clinicaltrials.gov registration number: NCT02384018). Stem Cells Translational Medicine 2018;7:11-19. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  18. Clinical and epidemiological aspects of cornea transplant patients of a reference hospital 1

    Science.gov (United States)

    Cruz, Giovanna Karinny Pereira; de Azevedo, Isabelle Campos; Carvalho, Diana Paula de Souza Rego Pinto; Vitor, Allyne Fortes; Santos, Viviane Euzébia Pereira; Ferreira, Marcos Antonio

    2017-01-01

    ABSTRACT Objective: clinically characterizing cornea transplant patients and their distribution according to indicated and post-operative conditions of cornea transplantation, as well as estimating the average waiting time. Method: a cross-sectional, descriptive and analytical study performed for all cornea transplants performed at a reference service (n=258). Data were analyzed using Statistical Package for the Social Sciences, version 20.0. Results: the main indicator for cornea transplant was keratoconus. The mean waiting time for the transplant was approximately 5 months and 3 weeks for elective transplants and 9 days for urgent cases. An association between the type of corneal disorder with gender, age, previous surgery, eye classification, glaucoma and anterior graft failure were found. Conclusion: keratoconus was the main indicator for cornea transplant. Factors such as age, previous corneal graft failure (retransplantation), glaucoma, cases of surgeries prior to cornea transplant (especially cataract surgery) may be related to the onset corneal endothelium disorders. PMID:28614429

  19. Optimal formation of genetically modified and functional pancreatic islet spheroids by using hanging-drop strategy.

    Science.gov (United States)

    Kim, H J; Alam, Z; Hwang, J W; Hwang, Y H; Kim, M J; Yoon, S; Byun, Y; Lee, D Y

    2013-03-01

    Rejection and hypoxia are important factors causing islet loss at an early stage after pancreatic islet transplantation. Recently, islets have been dissociated into single cells for reaggregation into so-called islet spheroids. Herein, we used a hanging-drop strategy to form islet spheroids to achieve functional equivalence to intact islets. To obtain single islet cells, we dissociated islets with trypsin-EDTA digestion for 10 minutes. To obtain spheroids, we dropped various numbers of single cells (125, 250, or 500 cells/30 μL drop) onto a Petri dish, that was inverted for incubation in humidified air containing 5% CO(2) at 37 °C for 7 days. The aggregated spheroids in the droplets were harvested for further culture. The size of the aggregated islet spheroids depended on the number of single cells (125-500 cells/30 μL droplet). Their morphology was similar to that of intact islets without any cellular damage. When treated with various concentrations of glucose to evaluate responsiveness, their glucose-mediated stimulation index value was similar to that of intact islets, an observation that was attributed to strong cell-to-cell interactions in islet spheroids. However, islet spheroids aggregated in general culture dishes showed abnormal glucose responsiveness owing to weak cell-to-cell interactions. Cell-to-cell interactions in islet spheroids were confirmed with an anti-connexin-36 monoclonal antibody. Finally, nonviral poly(ethylene imine)-mediated interleukin-10 cytokine gene delivered beforehand into dissociated single cells before formation of islet spheroids increased the gene transfection efficacy and interleukin-10 secretion from islet spheroids >4-fold compared with intact islets. These results demonstrated the potential application of genetically modified, functional islet spheroids with of controlled size and morphology using an hanging-drop technique. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Current and Future Perspectives on Alginate Encapsulated Pancreatic Islet.

    Science.gov (United States)

    Strand, Berit L; Coron, Abba E; Skjak-Braek, Gudmund

    2017-04-01

    Transplantation of pancreatic islets in immune protective capsules holds the promise as a functional cure for type 1 diabetes, also about 40 years after the first proof of principal study. The concept is simple in using semipermeable capsules that allow the ingress of oxygen and nutrients, but limit the access of the immune system. Encapsulated human islets have been evaluated in four small clinical trials where the procedure has been evaluated as safe, but lacking long-term efficacy. Host reactions toward the biomaterials used in the capsules may be one parameter limiting the long-term function of the graft in humans. The present article briefly discusses important capsule properties such as stability, permeability and biocompatibility, as well as possible strategies to overcome current challenges. Also, recent progress in capsule development as well as the production of insulin-producing cells from human stem cells that gives promising perspectives for the transplantation of encapsulated insulin-producing tissue is briefly discussed. Stem Cells Translational Medicine 2017;6:1053-1058. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  1. A simple assay for the detection of antibodies to endocrine islet cell surface antigens

    International Nuclear Information System (INIS)

    Contreas, G.; Madsen, O.D.; Vissing, H.; Lernmark, Aa.

    1986-01-01

    A simple and sensitive immunoradiometric assay for the detection of islet cell surface antibodies (CIRMA) has been developed. Live, transformed islet cells derived from a liver metastasis of a transplantable islet cell tumor were grown in removable microtiter wells and incubated with antibody. Cell-bound antibodies were quantitated using 125 I-labelled second antibodies. The assay was used to detect islet cell antibodies present in sera from non-diabetic and diabetic BB rats and proved to be particularly effective for screening hybridoma supernatants in order to identify monoclonal antibodies recognizing islet cell surface antigens. (Auth.)

  2. Islet neogenesis potential of human adult stem cells and its applications in cell replacement therapy for diabetes

    Directory of Open Access Journals (Sweden)

    Bhonde RR

    2008-11-01

    Full Text Available In recent years regenerative biology has reached to greater heights due to its therapeutic potential in treating degenerative diseases; as they are not curable by modern medicine. With the advent of research in stem cells and developmental biology the regenerative potential of adult resident stem cells is becoming clearer. The long term objective of regenerative medicine or cell therapy is to treat patients with their own stem cells. These stem cells could be derived from the diseased organs such as skin, liver, pancreas etc. or from reservoirs of multipotent stem cells such as bone marrow or cord blood.Manipulating the ability of tissue resident stem cells as well as from multipotent reservoirs such as bone marrow, umbilical cord and cord blood to give rise to endocrine cells may open new avenues in the treatment of diabetes. A better understanding of stem cell biology would almost certainly allow for the establishment of efficient and reliable cell transplantation experimental programs in the clinic. We show here that multipotent mesenchymal stem cells can be isolated from various sources such as the bone marrow, placenta, umbilical cord. Upon stimulation with specific growth factors they differentiate into islet like clusters (ILCs. When ILCs obtained from the above mentioned sources were transplanted in experimental diabetic mice, restoration of normoglycemia was observed within three weeks of transplantation with concomitant increase in the body weight. These euglycemic mice exhibited normal glucose tolerance test indicating normal utilization of glucose. Allthough the MSCs isolated from all the sources had the same characteristics; they showed significant differences in their islet differentiation potential. ILCs isolated for the human bone marrow did not show any pancreatic hormones in vitro, but upon transplantation they matured into insulin and somatostatin producing hormones. Placental MSCs as well as ILCs showed insulin trascripts

  3. Magnetic resonance imaging of mouse islet grafts labeled with novel chitosan-coated superparamagnetic iron oxide nanoparticles.

    Directory of Open Access Journals (Sweden)

    Jyuhn-Huarng Juang

    Full Text Available To better understand the fate of islet isografts and allografts, we utilized a magnetic resonance (MR imaging technique to monitor mouse islets labeled with a novel MR contrast agent, chitosan-coated superparamagnetic iron oxide (CSPIO nanoparticles.After being incubated with and without CSPIO (10 µg/ml, C57BL/6 mouse islets were examined under transmission electron microscope (TEM and their insulin secretion was measured. Cytotoxicity was examined in α (αTC1 and β (NIT-1 and βTC cell lines as well as islets. C57BL/6 mice were used as donors and inbred C57BL/6 and Balb/c mice were used as recipients of islet transplantation. Three hundred islets were transplanted under the left kidney capsule of each mouse and then MR was performed in the recipients periodically. At the end of study, the islet graft was removed for histology and TEM studies.After incubation of mouse islets with CSPIO (10 µg/mL, TEM showed CSPIO in endocytotic vesicles of α- and β-cells at 8 h. Incubation with CSPIO did not affect insulin secretion from islets and death rates of αTC1, NIT-1 and βTC cell lines as well as islets. After syngeneic and allogeneic transplantation, grafts of CSPIO-labeled islets were visualized on MR scans as persistent hypointense areas. At 8 weeks after syngeneic transplantation and 31 days after allogeneic transplantation, histology of CSPIO-labeled islet grafts showed colocalized insulin and iron staining in the same areas but the size of allografts decreased with time. TEM with elementary iron mapping demonstrated CSPIO distributed in the cytoplasm of islet cells, which maintained intact ultrastructure.Our results indicate that after syngeneic and allogeneic transplantation, islets labeled with CSPIO nanoparticles can be effectively and safely imaged by MR.

  4. Automated Analysis of Microscopic Images of Isolated Pancreatic Islets

    Czech Academy of Sciences Publication Activity Database

    Habart, D.; Švihlík, J.; Schier, Jan; Cahová, M.; Girman, P.; Zacharovová, K.; Berková, Z.; Kříž, J.; Fabryová, E.; Kosinová, L.; Papáčková, Z.; Kybic, J.; Saudek, F.

    2016-01-01

    Roč. 25, č. 12 (2016), s. 2145-2156 ISSN 0963-6897 Grant - others:GA ČR(CZ) GA14-10440S Institutional support: RVO:67985556 Keywords : enumeration of islets * image processing * image segmentation * islet transplantation * machine-learning * quality control Subject RIV: IN - Informatics, Computer Science Impact factor: 3.006, year: 2016 http://library.utia.cas.cz/separaty/2016/ZOI/schier-0465945.pdf

  5. Infection in the bone marrow transplant recipient and role of the microbiology laboratory in clinical transplantation.

    OpenAIRE

    LaRocco, M T; Burgert, S J

    1997-01-01

    Over the past quarter century, tremendous technological advances have been made in bone marrow and solid organ transplantation. Despite these advances, an enduring problem for the transplant recipient is infection. As immunosuppressive regimens have become more systematic, it is apparent that different pathogens affect the transplant recipient at different time points in the posttransplantation course, since they are influenced by multiple intrinsic and extrinsic factors. An understanding of ...

  6. Clinical outcome of combined conjunctival autograft transplantation and amniotic membrane transplantation in pterygium surgery

    OpenAIRE

    Tejsu Malla; Jing Jiang; Kai Hu

    2018-01-01

    AIM: To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques: combined conjunctival autograft and overlay amniotic membrane transplantation (CAT with AMT), conjunctival autograft transplantation (CAT) alone and amniotic membrane transplantation (AMT) alone. METHODS: In this retrospective study, 142 eyes of 142 pterygium patients (104 primary, 38 recurrent) who underwent CAT (group A), AMT (group B) or CAT with AMT (group C) respectively follo...

  7. Clinical Outcomes of Lung Transplantation in Patients with Telomerase Mutations

    Science.gov (United States)

    Tokman, Sofya; Singer, Jonathan P.; Devine, Megan S.; Westall, Glen P.; Aubert, John-David; Tamm, Michael; Snell, Gregory I.; Lee, Joyce S.; Goldberg, Hilary J.; Kukreja, Jasleen; Golden, Jeffrey A.; Leard, Lorriana E.; Garcia, Christine K.; Hays, Steven R.

    2017-01-01

    Background Successful lung transplantation (LT) for patients with pulmonary fibrosis from telomerase mutations is limited by systemic complications of telomerase dysfunction including myelosuppression, cirrhosis, and malignancy. We describe clinical outcomes among 14 LT recipients with telomerase mutations. Methods Subjects underwent LT between February 2005 and April 2014 at 5 LT centers. We abstracted data from medical records, focusing on outcomes reflecting post-LT treatment effects likely to be complicated by telomerase mutations. Results The median age of subjects was 60.5 years (IQR 52.0–62.0), 64.3% were male, and the mean post-LT observation time was 3.2 years (SD ±2.9). Eleven subjects had a mutation in telomerase reverse transcriptase, 2 in telomerase RNA component, and 1 had an uncharacterized mutation. Ten subjects were leukopenic post-LT; leukopenia prompted cessation of mycophenolate mofetil in 5 and treatment with filgrastim in 4. Six subjects had recurrent lower respiratory tract infections (LRTI), 7 had acute cellular rejection (ACR) (A1), and 4 developed chronic lung allograft dysfunction (CLAD). Ten LT recipients developed chronic renal insufficiency and 8 experienced acute, reversible renal failure. Three developed cancer, none had cirrhosis. Thirteen subjects were alive at data censorship. Conclusions The clinical course for LT recipients with telomerase mutations is complicated by renal disease, leukopenia prompting a change in the immunosuppressive regimen, and recurrent LTRI. In contrast, cirrhosis was absent, ACR was mild, and development of CLAD was comparable to other LT populations. While posing challenges, lung transplantation may be feasible for patients with pulmonary fibrosis due to telomerase mutations. PMID:26169663

  8. Effect of oxygenated perfluorocarbon on isolated islets during transportation.

    Science.gov (United States)

    Terai, Sachio; Tsujimura, Toshiaki; Li, Shiri; Hori, Yuichi; Toyama, Hirochika; Shinzeki, Makoto; Matsumoto, Ippei; Kuroda, Yoshikazu; Ku, Yonson

    2010-08-01

    Previous studies demonstrated the efficacy of the two-layer method (TLM) using oxygenated perfluorochemicals (PFC) for pancreas preservation. The current study investigated the effect of oxygenated PFC on isolated islets during transportation. Purified rat islets were stored in an airtight conical tube for 24h in RPMI culture medium at 22 degrees C or University of Wisconsin solution (UW) at 4 degrees C, either with or without oxygenated PFC. After storage, the islets were assessed for in vitro viability by static incubation (SI), FDA/PI staining, and energy status (ATP, energy charge, and ADP/ATP ratio) and for in vivo viability by a transplantation study. UW at 4 degrees C and RPMI medium at 22 degrees C maintained islet quality almost equally in both in vitro and in vivo assessments. The ATP levels and energy status in the groups with PFC were significantly lower than those without PFC. The groups with PFC showed a significantly higher ADP/ATP ratio than those without PFC. In the transplantation study, blood glucose levels and AUC in the UW+PFC group were significantly higher than those in UW group. UW at 4 degrees C and RPMI medium at 22 degrees C maintained islet quality equally under the conditions for islet transportation. The addition of oxygenated PFC, while advantageous for pancreas preservation, is not useful for islet transportation. Copyright 2010 Elsevier Inc. All rights reserved.

  9. Use of clinical practice guidelines to promote best practice when managing clinical interventions for liver transplant candidates.

    Science.gov (United States)

    Jarrett, Maree

    2009-06-01

    Limited organ availability and an increasing demand for organ transplantation has extended transplant waiting times and thus increased morbidity and mortality for potential recipients on waiting lists. The Queensland Liver Transplant Service identified use of clinical practice guidelines developed from evidence-based practice as a strategic clinical management/workflow tool that could improve clinical outcomes for patients awaiting liver transplant. An extensive review of publications related to the management of advanced liver disease in potential transplant recipients was undertaken and the supporting evidence was identified. In all stages of development of the guidelines, the multidisciplinary collaborative team of clinicians used recommended principles from The Appraisal of Guidelines, Research and Evaluation collaboration. The liver transplant recipient coordinator acted as facilitator for the project, identifying positive factors and resolving obstacles. Key focus areas in optimizing medical management before liver transplant were identified with the aim of preventing disease progression and complications that would jeopardize patients' outcome. Clinical practice guidelines were developed for each key area to optimize care by promoting appropriate timing of clinical interventions. Practices that required change to comply with identified best practice were investigated, and clinical practice for the outpatient medical management of potential liver transplant recipients with chronic liver disease were developed collaboratively. These guidelines have been accepted and are being implemented within the gastroenterology and hepatology department at the Princess Alexandra Hospital.

  10. Design of bioartificial pancreas with functional micro/nano-based encapsulation of islets.

    Science.gov (United States)

    Kepsutlu, Burcu; Nazli, Caner; Bal, Tugba; Kizilel, Seda

    2014-01-01

    Type I diabetes mellitus (TIDM), a devastating health issue in all over the world, has been treated by successful transplantation of insulin secreting pancreatic islets. However, serious limitations such as the requirement of immunosuppressive drugs for recipient patients, side effects as a result of long-term use of drugs, and reduced functionality of islets at the transplantation site remain. Bioartificial pancreas that includes islets encapsulated within semi-permeable membrane has been considered as a promising approach to address these requirements. Many studies have focused on micro or nanobased islet immunoisolation systems and tested the efficacy of encapsulated islets using in vitro and in vivo platforms. In this review, we address current progress and obstacles for the development of a bioartificial pancreas using micro/nanobased systems for encapsulation of islets.

  11. Activin receptor-like kinase 5 inhibition reverses impairment of endothelial cell viability by endogenous islet mesenchymal stromal cells.

    Science.gov (United States)

    Clarkin, Claire E; King, Aileen J; Dhadda, Paramjeet; Chagastelles, Pedro; Nardi, Nance; Wheeler-Jones, Caroline P; Jones, Peter M

    2013-03-01

    Following islet transplantation, islet graft revascularization is compromised due to loss of endothelial cells (ECs) during islet culture. TGF-β signaling pathways are essential for vascular homeostasis but their importance for islet EC function is unclear. We have identified a population of multipotent mesenchymal stromal cells (MSCs) within islets and investigated how modulation of TGF-β signaling by these cells influences islet EC viability. Cultured islets exhibited reduced expression of EC markers (VEGFR2, VE-cadherin and CD31), which was associated with diminished but sustained expression of endoglin a marker of both ECs and MSCs. Double fluorescent labeling of islets in situ with the EC marker CD31 disclosed a population of CD31-negative cells which were positive for endoglin. In vitro coculture of microvascular ECs with endoglin-positive, CD31-negative islet MSCs reduced VEGFR2 protein expression, disrupted EC angiogenic behavior, and increased EC detachment. Medium conditioned by islet MSCs significantly decreased EC viability and increased EC caspase 3/7 activity. EC:MSC cocultures showed enhanced Smad2 phosphorylation consistent with altered ALK5 signaling. Pharmacological inhibition of ALK5 activity with SB431542 (SB) improved EC survival upon contact with MSCs, and SB-treated cultured islets retained EC marker expression and sensitivity to exogenous VEGF164 . Thus, endoglin-expressing islet MSCs influence EC ALK5 signaling in vitro, which decreases EC viability, and changes in ALK5 activity in whole cultured islets contribute to islet EC loss. Modifying TGF-β signaling may enable maintenance of islet ECs during islet isolation and thus improve islet graft revascularization post-transplantation. Copyright © 2013 AlphaMed Press.

  12. PD-L1 Deficiency within Islets Reduces Allograft Survival in Mice.

    Directory of Open Access Journals (Sweden)

    Dongxia Ma

    Full Text Available Islet transplantation may potentially cure type 1 diabetes mellitus (T1DM. However, immune rejection, especially that induced by the alloreactive T-cell response, remains a restraining factor for the long-term survival of grafted islets. Programmed death ligand-1 (PD-L1 is a negative costimulatory molecule. PD-L1 deficiency within the donor heart accelerates allograft rejection. Here, we investigate whether PD-L1 deficiency in donor islets reduces allograft survival time.Glucose Stimulation Assays were performed to evaluate whether PD-L1 deficiency has detrimental effects on islet function. Islets isolated from PDL1-deficient mice or wild- type (WT mice (C57BL/6j were implanted beneath the renal capsule of streptozotocin (STZ-induced diabetic BALB/c mice. Blood glucose levels and graft survival time after transplantation were monitored. Moreover, we analyzed the residual islets, infiltrating immune cells and alloreactive cells from the recipients.PD-L1 deficiency within islets does not affect islet function. However, islet PD-L1 deficiency increased allograft rejection and was associated with enhanced inflammatory cell infiltration and recipient T-cell alloreactivity.This is the first report to demonstrate that PD-L1 deficiency accelerated islet allograft rejection and regulated recipient alloimmune responses.

  13. Alginate Microencapsulation of Human Islets Does Not Increase Susceptibility to Acute Hypoxia

    Directory of Open Access Journals (Sweden)

    I. K. Hals

    2013-01-01

    Full Text Available Islet transplantation in diabetes is hampered by the need of life-long immunosuppression. Encapsulation provides partial immunoprotection but could possibly limit oxygen supply, a factor that may enhance hypoxia-induced beta cell death in the early posttransplantation period. Here we tested susceptibility of alginate microencapsulated human islets to experimental hypoxia (0.1–0.3% O2 for 8 h, followed by reoxygenation on viability and functional parameters. Hypoxia reduced viability as measured by MTT by 33.8±3.5% in encapsulated and 42.9±5.2% in nonencapsulated islets (P<0.2. Nonencapsulated islets released 37.7% (median more HMGB1 compared to encapsulated islets after hypoxic culture conditions (P<0.001. Glucose-induced insulin release was marginally affected by hypoxia. Basal oxygen consumption was equally reduced in encapsulated and nonencapsulated islets, by 22.0±6.1% versus 24.8±5.7%. Among 27 tested cytokines/chemokines, hypoxia increased the secretion of IL-6 and IL-8/CXCL8 in both groups of islets, whereas an increase of MCP-1/CCL2 was seen only with nonencapsulated islets. Conclusion. Alginate microencapsulation of human islets does not increase susceptibility to acute hypoxia. This is a positive finding in relation to potential use of encapsulation for islet transplantation.

  14. Clinical significance of /sup 99m/technetium sulfur colloid accumulation in renal transplant patients

    International Nuclear Information System (INIS)

    Kim, Y.C.; Massari, P.U.; Brown, M.L.; Thrall, J.H.; Chang, B.; Keyes, J.W. Jr.

    1977-01-01

    The accumulation of /sup 99m/technetium sulfur colloid (/sup 99m/TcSC) was evaluated in 47 studies performed on 19 renal transplant patients by comparing its transplant activity to its bone marrow accumulation. There was a diagnosis of rejection in 21 of 22 studies (96.5 percent) in which marked transplant accumulation was noted. In 11 studies of patients with a clinical diagnosis of post-transplant acute tubular necrosis (ATN), the transplant activity varied from none to moderate. Rejection developed in 5 of 6 studies with minimal to moderate accumulation. Normally functioning renal transplant patients, or those with ATN and no superimposed rejection, do not show evidence of /sup 99m/TcSC accumulation

  15. Effect of total lymphoid irradiation and pretransplant blood transfusion on pancreatic islet allograft survival

    International Nuclear Information System (INIS)

    Mendez-Picon, G.; McGeorge, M.

    1983-01-01

    Total lymphoid irradiation (TLI) has been shown to have a strong immunosuppressive effect both experimentally and clinically. Pretransplant blood transfusions have also been shown to have a strong beneficial effect in the outcome of organ transplantation. A study was made of the effect of TLI and pretransplant blood transfusions, alone and in combination, as an immunosuppressive modality in the isolated pancreatic islet transplant in the rat model. Donor rats (Fischer RT1v1) were kept on a 50% DL-ethionine supplemented diet for 4-6 weeks prior to pancreas removal. Recipient rats (Lewis RT1) were made diabetics prior to transplantation by iv injection of streptozotocin (45 mg/kg). Transfusion protocol consisted of a biweekly transfusion of 2 ml of either donor specific or third party transfusions. Total lymphoid irradiation was carried out by daily administration of 200 rads during one week prior to transplantation. Transplantation of the isolated islets was performed by intraportal injection. Syngeneic transplant of one and a half donor pancreata in each recipient reverted the diabetic condition indefinitely (greater than 100 days). Untreated allogenic grafts had a mean survival time (MST) of 5.2 days. Total lymphoid irradiation in dosages of 800, 1000, and 1200 rads, as the only immunosuppressive regimen, prolonged the MST of allografts to 15.3, 16.5, and 21.8 days, respectively (P less than .05). Pretransplant third party blood transfusion had no effect on allograft survival (MST 6.0). When donor specific blood transfusions were given, the MST was prolonged to 25.3 days (P less than .05). When TLI was administered to recipients of donor specific transfusions, the MST of the allografts did not show any statistical significant difference when compared with untreated animals. This abrogation of the beneficial effect of specific blood transfusion was observed in all dosages of TLI employed: 800 rad (MST 3.0), 1000 rad (MST 8.0), 1200 rad (MST 5.18)

  16. TRANSPLANTATION

    African Journals Online (AJOL)

    stage ... renal artery thrombosis, renal vein thrombosis, ureteric leak or stenosis ... alternative organ source for patients with end-stage renal disease. Kidney ... status.27,28 Post-transplant acute tubular necrosis is caused by ischaemic injury to the ...

  17. Ex vivo lung perfusion in clinical lung transplantation--state of the art.

    Science.gov (United States)

    Andreasson, Anders S I; Dark, John H; Fisher, Andrew J

    2014-11-01

    Ex vivo lung perfusion (EVLP) has emerged as a new technique for assessing and potentially reconditioning human donor lungs previously unacceptable for clinical transplantation with the potential to dramatically push the limits of organ acceptability. With the recent introduction of portable EVLP, a new era in lung preservation may be upon us with the opportunity to also limit organ ischaemic times and potentially improve the outcome of donor lungs already deemed acceptable for transplantation. It took over half a century for the technique to evolve from basic theory to semi-automated circuits fit for clinical use that are now rapidly being adopted in transplant centres across the globe. With this field in constant evolution and many unanswered questions remaining, our review serves as an update on the state of the art of EVLP in clinical lung transplantation. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  18. Endothelial chimerism and vascular sequestration protect pancreatic islet grafts from antibody-mediated rejection

    Science.gov (United States)

    Chen, Chien-Chia; Pouliquen, Eric; Broisat, Alexis; Andreata, Francesco; Racapé, Maud; Bruneval, Patrick; Kessler, Laurence; Ahmadi, Mitra; Bacot, Sandrine; Saison-Delaplace, Carole; Marcaud, Marina; Van Huyen, Jean-Paul Duong; Loupy, Alexandre; Villard, Jean; Demuylder-Mischler, Sandrine; Morelon, Emmanuel; Tsai, Meng-Kun; Kolopp-Sarda, Marie-Nathalie; Koenig, Alice; Mathias, Virginie; Ghezzi, Catherine; Dubois, Valerie; Defrance, Thierry

    2017-01-01

    Humoral rejection is the most common cause of solid organ transplant failure. Here, we evaluated a cohort of 49 patients who were successfully grafted with allogenic islets and determined that the appearance of donor-specific anti-HLA antibodies (DSAs) did not accelerate the rate of islet graft attrition, suggesting resistance to humoral rejection. Murine DSAs bound to allogeneic targets expressed by islet cells and induced their destruction in vitro; however, passive transfer of the same DSAs did not affect islet graft survival in murine models. Live imaging revealed that DSAs were sequestrated in the circulation of the recipients and failed to reach the endocrine cells of grafted islets. We used murine heart transplantation models to confirm that endothelial cells were the only accessible targets for DSAs, which induced the development of typical microvascular lesions in allogeneic transplants. In contrast, the vasculature of DSA-exposed allogeneic islet grafts was devoid of lesions because sprouting of recipient capillaries reestablished blood flow in grafted islets. Thus, we conclude that endothelial chimerism combined with vascular sequestration of DSAs protects islet grafts from humoral rejection. The reduced immunoglobulin concentrations in the interstitial tissue, confirmed in patients, may have important implications for biotherapies such as vaccines and monoclonal antibodies. PMID:29202467

  19. Alotransplante de ilhotas de Langerhans no fígado de ratos submetidos a manipulação tímica com células não-parenquimatosas Allogenic islet transplantation on the rat liver after allogenic nonparenchymal cells injection in the thymus

    Directory of Open Access Journals (Sweden)

    Eleazar Chaib

    2006-12-01

    éticos, antes do alotransplante de ilhotas de Langerhans no fígado, ao contrário de inibir a reação do receptor contra o enxerto, prolongando a sobrevida média das ilhotas e, possivelmente, levando ao estado de tolerância imunológica, induziu ao processo de rejeição aguda precoce.BACKGROUD: The major indication for pancreas or islet transplantation is diabetes mellitus type I. This process has to supply the insulin necessity keeping glucose under control AIM: We studied allogenic islet transplantation on the rat liver, Wistar (RT1u to Lewis (RT1¹ as a recipient. Control group (n = 8 and nonparenchymal cell group (n = 8 respectively with injection of Hanks solution and nonparenchymal cells in the thymus before islet transplantation. MATERIAL AND METHODS: With the method of isolation and purification of the islets we obtained both in the control group 3.637 ± 783,3 islets with purity of 85 ± 3,52% and nonparenchymal cell group 3.270 ± 770 islets with purity of 84,25 ± 2,76%. The nonparenchymal cells were retrieved from the liver and we obtained 2 x 106 cells. Diabetes was induced by i.v. streptozotocin RESULTS: Control group the transplantation of 3.637 ± 783,3 islets in the rat liver normalized glucose test, 7,21 ± 0,57 mmol/L in the 2nd postoperative day. Acute rejection came in the 6th postoperative day with significantly increase of glucose test in nonparenchymal cell group, the transplantation of 3.270 ± 770 islets in the rat liver, almost normalized the glucose test was 17,95 ± 5,33 mmol/L in the 2nd postoperative day. From the 4th postoperative day to 10th postoperative day. The glucose test increase significantly showing an early acute rejection CONCLUSION: The injection of nonparenchymal cells in the thymus before allogenic islet transplantation in the rat liver lead to an early acute rejection.

  20. Alginate Microencapsulation of Human Islets Does Not Increase Susceptibility to Acute Hypoxia

    Science.gov (United States)

    Hals, I. K.; Rokstad, A. M.; Strand, B. L.; Oberholzer, J.; Grill, V.

    2013-01-01

    Islet transplantation in diabetes is hampered by the need of life-long immunosuppression. Encapsulation provides partial immunoprotection but could possibly limit oxygen supply, a factor that may enhance hypoxia-induced beta cell death in the early posttransplantation period. Here we tested susceptibility of alginate microencapsulated human islets to experimental hypoxia (0.1–0.3% O2 for 8 h, followed by reoxygenation) on viability and functional parameters. Hypoxia reduced viability as measured by MTT by 33.8 ± 3.5% in encapsulated and 42.9 ± 5.2% in nonencapsulated islets (P microencapsulation of human islets does not increase susceptibility to acute hypoxia. This is a positive finding in relation to potential use of encapsulation for islet transplantation. PMID:24364039

  1. Benefits of a transfer clinic in adolescent and young adult kidney transplant patients.

    Science.gov (United States)

    McQuillan, Rory F; Toulany, Alene; Kaufman, Miriam; Schiff, Jeffrey R

    2015-01-01

    Adolescent and young adult kidney transplant recipients have worse graft outcomes than older and younger age groups. Difficulties in the process of transition, defined as the purposeful, planned movement of adolescents with chronic health conditions from child to adult-centered health care systems, may contribute to this. Improving the process of transition may improve adherence post-transfer to adult care services. The purpose of this study is to investigate whether a kidney transplant transfer clinic for adolescent and young adult kidney transplant recipients transitioning from pediatric to adult care improves adherence post-transfer. We developed a joint kidney transplant transfer clinic between a pediatric kidney transplant program, adult kidney transplant program, and adolescent medicine at two academic health centers. The transfer clinic facilitated communication between the adult and pediatric transplant teams, a face-to-face meeting of the patient with the adult team, and a meeting with the adolescent medicine physician. We compared the outcomes of 16 kidney transplant recipients transferred before the clinic was established with 16 patients who attended the clinic. The primary outcome was a composite measure of non-adherence. Non-adherence was defined as either self-reported medication non-adherence or displaying two of the following three characteristics: non-attendance at clinic, non-attendance for blood work appointments, or undetectable calcineurin inhibitor levels within 1 year post-transfer. The two groups were similar at baseline, with non-adherence identified in 43.75 % of patients. Non-adherent behavior in the year post-transfer, which included missing clinic visits, missing regular blood tests, and undetectable calcineurin inhibitor levels, was significantly lower in the cohort which attended the transfer clinic (18.8 versus 62.5 %, p = 0.03). The median change in estimated glomerular filtration rate (eGFR) in the year following transfer

  2. Benefits of a Transfer Clinic in Adolescent and Young Adult Kidney Transplant Patients

    Directory of Open Access Journals (Sweden)

    Rory F. McQuillan

    2015-12-01

    Full Text Available Background: Adolescent and young adult kidney transplant recipients have worse graft outcomes than older and younger age groups. Difficulties in the process of transition, defined as the purposeful, planned movement of adolescents with chronic health conditions from child to adult-centered health care systems, may contribute to this. Improving the process of transition may improve adherence post-transfer to adult care services. Objective: The purpose of this study is to investigate whether a kidney transplant transfer clinic for adolescent and young adult kidney transplant recipients transitioning from pediatric to adult care improves adherence post-transfer. Methods: We developed a joint kidney transplant transfer clinic between a pediatric kidney transplant program, adult kidney transplant program, and adolescent medicine at two academic health centers. The transfer clinic facilitated communication between the adult and pediatric transplant teams, a face-to-face meeting of the patient with the adult team, and a meeting with the adolescent medicine physician. We compared the outcomes of 16 kidney transplant recipients transferred before the clinic was established with 16 patients who attended the clinic. The primary outcome was a composite measure of non-adherence. Non-adherence was defined as either self-reported medication non-adherence or displaying two of the following three characteristics: non-attendance at clinic, non-attendance for blood work appointments, or undetectable calcineurin inhibitor levels within 1 year post-transfer. Results: The two groups were similar at baseline, with non-adherence identified in 43.75 % of patients. Non-adherent behavior in the year post-transfer, which included missing clinic visits, missing regular blood tests, and undetectable calcineurin inhibitor levels, was significantly lower in the cohort which attended the transfer clinic (18.8 versus 62.5 %, p = 0.03. The median change in estimated glomerular

  3. Anti-inflammatory thalidomide improves islet grafts survival and functions in a xenogenic environment.

    Directory of Open Access Journals (Sweden)

    Chunguang Chen

    Full Text Available Thalidomide possesses both anti-inflammatory and anti-angiogenic properties. This study investigates its potential application in islet transplantation with a xenogenic transplantation model. Transplantation was performed using C57Bl/6 mice and NMRI nu/nu mice as recipients of porcine islets. Moreover, islet graft vasculature and inflammation were investigated to identify the mechanisms of thalidomide action. In the immunocompetent environment of C57Bl/6 mice, a fast graft rejection was observed. The group treated with thalidomide 200 mg/kg BW per day achieved and maintained euglycemia in the complete observation period for 42 days. The treated mice had more functional islet graft mass with less leukocyte infiltration. The pro-inflammatory TNF-alpha and VEGF content in islet grafted kidneys was significantly lowered by the treatment. By comparison, thalidomide was not effective in improving graft survival in immunocompromised nude mice. It strongly inhibited the VEGF and TNF-alpha-induced endothelial proliferation of isolated pig islets in a dose dependent manner. The magnitude of thalidomide's inhibitory effect was nearly identical to the effect of VEGF- receptor 2 inhibitor SU416 and anti-TNF-receptor 1 neutralizing antibody, and was reversed by sphingosine-1-phosphate. In conclusion, the anti-inflammatory effect of thalidomide improved islet graft survival and function in a transplantation model with a maximum immune barrier.

  4. Is ABPM clinically useful after pediatric solid organ transplantation?

    Science.gov (United States)

    Soergel, Marianne

    2004-10-01

    When ambulatory blood pressure monitoring (ABPM) is performed in populations with a high risk for secondary hypertension, such as solid organ transplant recipients, hypertension or abnormalities in circadian blood pressure variability are often discovered even in patients with normal office blood pressure (BP). To discuss whether ABPM should be routinely assessed in pediatric solid organ recipients, the available information on pathological findings, association of ABPM abnormalities with outcome parameters, and treatment options is reviewed. ABPM is a useful tool to optimize therapy in the large proportion of transplant recipients with confirmed hypertension. Whether the use of ABPM on a routine basis should be recommended for pediatric transplantation patients without office hypertension remains to be determined. Copyright 2004 Blackwell Munksgaard

  5. Electrofusion of mesenchymal stem cells and islet cells for diabetes therapy: a rat model.

    Directory of Open Access Journals (Sweden)

    Goichi Yanai

    Full Text Available Islet transplantation is a minimally invasive treatment for severe diabetes. However, it often requires multiple donors to accomplish insulin-independence and the long-term results are not yet satisfying. Therefore, novel ways to overcome these problems have been explored. Isolated islets are fragile and susceptible to pro-apoptotic factors and poorly proliferative. In contrast, mesenchymal stem cells (MSCs are highly proliferative, anti-apoptotic and pluripotent to differentiate toward various cell types, promote angiogenesis and modulate inflammation, thereby studied as an enhancer of islet function and engraftment. Electrofusion is an efficient method of cell fusion and nuclear reprogramming occurs in hybrid cells between different cell types. Therefore, we hypothesized that electrofusion between MSC and islet cells may yield robust islet cells for diabetes therapy. We establish a method of electrofusion between dispersed islet cells and MSCs in rats. The fusion cells maintained glucose-responsive insulin release for 20 days in vitro. Renal subcapsular transplantation of fusion cells prepared from suboptimal islet mass (1,000 islets that did not correct hyperglycemia even if co-transplanted with MSCs, caused slow but consistent lowering of blood glucose with significant weight gain within the observation period in streptozotocin-induced diabetic rats. In the fusion cells between rat islet cells and mouse MSCs, RT-PCR showed new expression of both rat MSC-related genes and mouse β-cell-related genes, indicating bidirectional reprogramming of both β-cell and MSCs nuclei. Moreover, decreased caspase3 expression and new expression of Ki-67 in the islet cell nuclei suggested alleviated apoptosis and gain of proliferative capability, respectively. These results show that electrofusion between MSCs and islet cells yield special cells with β-cell function and robustness of MSCs and seems feasible for novel therapeutic strategy for diabetes

  6. Effects of micro-encapsulation on morphology and endocrine function of cryopreserved neonatal porcine islet-like cell clusters.

    Science.gov (United States)

    Murakami, M; Satou, H; Kimura, T; Kobayashi, T; Yamaguchi, A; Nakagawara, G; Iwata, H

    2000-10-27

    For the success of clinical islets transplantation, the development of a long-term storage method is necessary. However, the structure of digested islets is scanty for culture and cryopreservation. In this study, the effect of micro-encapsulation to cryopreserved porcine islet-like cell clusters (ICCs) was investigated. The ICCs prepared from neonatal pigs by collagenase digestion and culture technique were cryopreserved and micro-encapsulated in 5% agarose membranes. After cryopreservation, ICC cultured without encapsulation (group A) and cultured with encapsulation (group B) were assessed by comparison with no cryopreserved ICC (control) both in vitro by static incubation test and in vivo in a xenotransplantation study. Micro-encapsulation was able to maintain the fine morphology and the number of ICCs of group B after 7 days of culture. There were not significant differences in insulin secretion of group B and control on day 1 and 7 of culture (1 day:11+/-0.99, 7 days: 5.30+/-1.08 microU/ICC/hr NS versus control). On day 7 of culture, the retrieval rate of group B (105.2+/-9.8%) is obviously higher compared with group A (63.0+/-6.3%). In the xenotransplatation model, the ICCs of group B showed long survival time (7.9+/-0.4 weeks) and good transplantation effect. Our study suggests that micro-encapsulation is one of the useful method for cryopreserved ICC to maintain the fine morphology and effectively recover the endocrine function.

  7. Demonstration of SLUMIS: a clinical database and management information system for a multi organ transplant program.

    OpenAIRE

    Kurtz, M.; Bennett, T.; Garvin, P.; Manuel, F.; Williams, M.; Langreder, S.

    1991-01-01

    Because of the rapid evolution of the heart, heart/lung, liver, kidney and kidney/pancreas transplant programs at our institution, and because of a lack of an existing comprehensive database, we were required to develop a computerized management information system capable of supporting both clinical and research requirements of a multifaceted transplant program. SLUMIS (ST. LOUIS UNIVERSITY MULTI-ORGAN INFORMATION SYSTEM) was developed for the following reasons: 1) to comply with the reportin...

  8. Prospective clinical testing of regulatory dendritic cells (DCreg) in organ transplantation

    OpenAIRE

    ANGUS W THOMSON; ALAN F ZAHORCHAK; Mohamed B. Ezzelarab; Lisa H. Butterfield; Fadi G. Lakkis; Diana M Metes

    2016-01-01

    Dendritic cells (DC) are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg) with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering...

  9. Biliary strictures and liver transplantation : clinical and biomedical aspects

    NARCIS (Netherlands)

    Sebib Korkmaz, Kerem

    2014-01-01

    The current thesis describes short and long term results of orthotopic liver transplantation (OLT) performed with livers from donation after brain death (DBD) and livers from donation after cardiac death (DCD) with an emphasis on biliary complications, especially nonanastomotic biliary strictures

  10. Clinical and immunological relevance of antibodies in solid organ transplantation.

    Science.gov (United States)

    Mehra, N K; Baranwal, A K

    2016-12-01

    The two important issues affecting recipients of solid organ transplants and of importance to immunologists are (i) sensitization of the recipient to HLA antigens and the resultant humoral immune response leading to the development of anti-HLA antibodies; and ii) development of robust assays for early detection of humoral rejection post-transplant. Evidence from several studies clearly indicates that presence of circulating anti-HLA antibodies especially donor specific leads to early graft loss and high titres of DSA may even lead to hyperacute or accelerated acute rejection. Long-term graft survival too is adversely affected by the presence of either pre- or post-transplant DSA. HLA matching status of the recipient - donor pair - is an important factor in the modulation of humoral response following transplantation and in a way affects de novo development of DSA. Data collected over the past decade clearly indicate significantly lower level of DSAs in optimally matched donor-recipient pairs. HLA mismatches especially those on HLA-DR and HLA-C loci have wider implications on post-transplant graft survival. The presence of circulating anti-HLA antibodies leads to endothelial damage in the newly grafted organ through complement dependent or independent pathways. Although detection of C4d deposition in renal biopsies serves as an important indicator of humoral rejection, its absence does not preclude the presence of DSAs and humoral rejection, and hence, it cannot be relied upon in every case. The emergence of epitope-based screening for anti-HLA antibodies on Luminex platform with high degree of sensitivity has revolutionized the screening for anti-HLA antibodies and DSAs. Studies indicate that humoral response to non-HLA antigens might also have a detrimental effect on allograft survival. High titres of such circulating antibodies may even lead to hyperacute rejection. Pre-emptive testing of solid organ recipients, especially kidney transplant recipients for anti

  11. Enhanced function of immuno-isolated islets in diabetes therapy by co-encapsulation with an anti-inflammatory drug

    OpenAIRE

    Dang, Tram T.; Thai, Anh V.; Cohen, Joshua; Slosberg, Jeremy E.; Siniakowicz, Karolina; Doloff, Joshua C.; Ma, Minglin; Hollister-Lock, Jennifer; Tang, Katherine; Gu, Zhen; Cheng, Hao; Weir, Gordon C.; Langer, Robert; Anderson, Daniel G.

    2013-01-01

    Immuno-isolation of islets has the potential to enable the replacement of pancreatic function in diabetic patients. However, host response to the encapsulated islets frequently leads to fibrotic overgrowth with subsequent impairment of the transplanted grafts. Here, we identified and incorporated anti-inflammatory agents into islet-containing microcapsules to address this challenge. In vivo subcutaneous screening of 16 small molecule anti-inflammatory drugs was performed to identify promising...

  12. Matching donor to recipient in liver transplantation: Relevance in clinical practice.

    Science.gov (United States)

    Reddy, Mettu Srinivas; Varghese, Joy; Venkataraman, Jayanthi; Rela, Mohamed

    2013-11-27

    Achieving optimum outcomes after liver transplantation requires an understanding of the interaction between donor, graft and recipient factors. Within the cohort of patients waiting for a transplant, better matching of the donor organ to the recipient will improve transplant outcomes and benefit the overall waiting list by minimizing graft failure and need for re-transplantation. A PubMed search was conducted to identify published literature investigating the effects of donor factors such as age, gender, ethnicity, viral serology; graft factors such as size and quality, recipient factors such as age, size, gender and transplant factors such as major or minor blood group incompatibility and immunological factors. We also report technical and therapeutic modifications that can be used to manage donor-recipient mismatch identified from literature and the authors' clinical experience. Multiple donor and recipient factors impact graft survival after liver transplantation. Appropriate matching based on donor-organ-recipient variables, modification of surgical technique and innovative peri-transplant strategies can increase the donor pool by utilizing grafts from marginal donors that are traditionally turned down.

  13. Cell Therapy in Organ Transplantation: Our Experience on the Clinical Translation of Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Niloufar Safinia

    2018-02-01

    Full Text Available Solid organ transplantation is the treatment of choice for patients with end-stage organ dysfunction. Despite improvements in short-term outcome, long-term outcome is suboptimal due to the increased morbidity and mortality associated with the toxicity of immunosuppressive regimens and chronic rejection (1–5. As such, the attention of the transplant community has focused on the development of novel therapeutic strategies to achieve allograft tolerance, a state whereby the immune system of the recipient can be re-educated to accept the allograft, averting the need for long-term immunosuppression. Indeed, reports of “operational” tolerance, whereby the recipient is off all immunosuppressive drugs and maintaining good graft function, is well documented in the literature for both liver and kidney transplantations (6–8. However, this phenomenon is rare and in the setting of liver transplantation has been shown to occur late after transplantation, with the majority of patients maintained on life-long immunosupression to prevent allograft rejection (9. As such, significant research has focused on immune regulation in the context of organ transplantation with regulatory T cells (Tregs identified as cells holding considerable promise in this endeavor. This review will provide a brief introduction to human Tregs, their phenotypic and functional characterization and focuses on our experience to date at the clinical translation of Treg immunotherapy in the setting of solid organ transplantation.

  14. Clinical data and CT findings of pulmonary infection caused by different pathogens after kidney transplantation

    International Nuclear Information System (INIS)

    Jiang Tao; Xue Feng; Zheng Xuan; Yu Hong; Tao Xiaofeng; Xiao Xiangsheng; Liu Shiyuan

    2012-01-01

    Purpose: The overall objective was to review clinical data and CT findings of pulmonary infection caused by different pathogens after kidney transplantation in an attempt to help early clinical qualitative diagnosis. Materials and methods: 446 cases of clinically confirmed pulmonary infection after kidney transplantation in recent 10 years were evaluated with respect to the time of occurrence and 89 cases with complete CT data and pathogenic diagnosis were further analyzed for pathogen types and CT manifestations. Statistical analysis was performed using Fisher's exact test. Results: Pulmonary infection reached the peak in 3 months after transplantation. Bacterial infection and mixed infection were predominant between 1 and 6 months. And most tuberculosis occurred after one year. Bacterial (38.2%) and mixed infections (38.2%) were the common types. The next was fungal infection, tuberculosis and viral infection (10.1%, 7.9% and 5.6%, respectively). CT manifestations of pulmonary infections after kidney transplantation were diverse and complex, lacking characteristic signs. Conclusion: More than 3/4 of pulmonary infections after kidney transplantation can be attributed to bacteria and mixed pathogens. The combination of time course, clinical data and CT manifestations plays an important role in the early clinical qualitative diagnosis.

  15. Everolimus: a proliferation signal inhibitor with clinical applications in organ transplantation, oncology, and cardiology.

    Science.gov (United States)

    Gabardi, Steven; Baroletti, Steven A

    2010-10-01

    Everolimus, a proliferation signal inhibitor in the mammalian target of rapamycin (mTOR) drug class, has many clinical applications, including in organ transplantation, oncology, and cardiology. It currently has United States Food and Drug Administration (FDA) approval for prophylaxis against rejection in de novo renal transplant recipients, treatment of renal cell carcinoma, and use as a drug-eluting stent. To review the pharmacology, pharmacokinetics, efficacy, and safety of everolimus, we performed a search of the MEDLINE database (January 1997-April 2010) for all English-language articles of in vitro and in vivo studies that evaluated everolimus, as well as abstracts from recent scientific meetings and the manufacturer. In transplantation, everolimus demonstrates immunosuppressive properties and has been used to prevent acute rejection in cardiac, liver, lung, and renal transplant recipients. It appears that this agent may be potent enough to allow for the minimization or removal of calcineurin inhibitors in the long-term management of renal transplant recipients. In oncology, everolimus has been proven effective for the management of treatment-resistant renal cell carcinoma. In cardiology, everolimus is available as a drug-coated stent and is used in percutaneous coronary interventions for prevention of restenosis. In transplant recipients and patients with renal cell carcinoma, everolimus appears to have an extensive adverse-event profile. The pharmacologic properties of everolimus differentiate this agent from other drugs used in these clinical areas, and its pharmacokinetic properties differentiate it from sirolimus.

  16. Sepsis after renal transplantation: Clinical, immunological, and microbiological risk factors.

    Science.gov (United States)

    Schachtner, Thomas; Stein, Maik; Reinke, Petra

    2017-06-01

    As immunosuppressive therapy and allograft survival have improved, the increased incidence of sepsis has become a major hurdle of disease-free survival after renal transplantation. We identified 112 of 957 kidney transplant recipients (KTRs) with sepsis. In all, 31 KTRs developed severe sepsis or septic shock, and 30 KTRs died from sepsis. KTRs without sepsis were used for comparison. CMV-specific and alloreactive T cells were measured using an interferon-γ Elispot assay. The extent of immunosuppression was quantified by lymphocyte subpopulations. Five-year patient survival was 70.3% with sepsis compared to 88.2% without (Psepsis (Psepsis (Psepsis was associated with decreased CD3+ and CD4+ T cells pre-transplantation (Psepsis (Psepsis (Psepsis show inferior patient survival and allograft function. Identified risk factors and differences in lymphocyte counts, CMV-specific immunity, and alloreactivity may prove useful to identify KTRs at increased risk. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Osteochondral Allograft Transplantation in Cartilage Repair: Graft Storage Paradigm, Translational Models, and Clinical Applications

    Science.gov (United States)

    Bugbee, William D.; Pallante-Kichura, Andrea L.; Görtz, Simon; Amiel, David; Sah, Robert

    2016-01-01

    The treatment of articular cartilage injury and disease has become an increasingly relevant part of orthopaedic care. Articular cartilage transplantation, in the form of osteochondral allografting, is one of the most established techniques for restoration of articular cartilage. Our research efforts over the last two decades have supported the transformation of this procedure from experimental “niche” status to a cornerstone of orthopaedic practice. In this Kappa Delta paper, we describe our translational and clinical science contributions to this transformation: (1) to enhance the ability of tissue banks to process and deliver viable tissue to surgeons and patients, (2) to improve the biological understanding of in vivo cartilage and bone remodeling following osteochondral allograft (OCA) transplantation in an animal model system, (3) to define effective surgical techniques and pitfalls, and (4) to identify and clarify clinical indications and outcomes. The combination of coordinated basic and clinical studies is part of our continuing comprehensive academic OCA transplant program. Taken together, the results have led to the current standards for OCA processing and storage prior to implantation and also novel observations and mechanisms of the biological and clinical behavior of OCA transplants in vivo. Thus, OCA transplantation is now a successful and increasingly available treatment for patients with disabling osteoarticular cartilage pathology. PMID:26234194

  18. Non-HLA antibodies post-transplantation: clinical relevance and treatment in solid organ transplantation.

    Science.gov (United States)

    Dragun, Duska; Hegner, Bjorn

    2009-01-01

    Antibodies and B cells are increasingly recognized as major modulators of allograft function and survival. Improved immunohistochemical and serologic diagnostic procedures have been developed to monitor antibody responses against HLA antigens during the last decade. Acute and chronic allograft rejection can occur in HLA-identical sibling transplants implicating the importance of immune response against non-HLA targets. Non-HLA anti-bodies may occur as alloantiboides, yet they seem to be predominantly autoantibodies. Antigenic targets of non-HLA antibodies described thus far include various minor histocompatibility antigens, vascular receptors, adhesion molecules, and intermediate filaments. Non-HLA antibodies may function as complement- and non-complement-fixing antibodies and they may induce a wide variety of allograft injuries, reflecting the complexity of their acute and chronic actions. Refined approaches considering the subtle mechanistic differences in the individual antibody responses directed against non-HLA antigens may help to define patients at particular risk for irreversible acute or chronic allograft injuries and improve over-all outcomes. We attempted to summarize the current state of research, development in diagnostic and therapeutic strategies, and to address some emerging problems in the area of humoral response against non-HLA antigens beyond ABO blood group and MHC class I chain-related gene A and B (MICA and MICB) antigens in solid organ transplantation. Copyright (c) 2009 S. Karger AG, Basel.

  19. Prolonged Survival of Subcutaneous Allogeneic Islet Graft by Donor Chimerism without Immunosuppressive Treatment

    Directory of Open Access Journals (Sweden)

    Brend Ray-Sea Hsu

    2017-01-01

    Full Text Available The aim of this study was to investigate whether tolerance-induced protection of islets in the renal subcapsular space can also prevent subcutaneous allogeneic islets from being rejected. We used bone marrow stem cells from C57BL/6 (H2b mice to construct donor chimerism in conditioned diabetic BALB/c (H2d mice and investigated the effect of donor chimerism on engraftment and survival of subcutaneously transplanted allogeneic islets in streptozotocin-induced diabetic mice. We also studied the anti-inflammatory effect of mesenchymal stem cell on islet engraftment. Full but not low-grade or no donor chimerism was associated with successful engraftment of allogeneic islets and restoration of normoglycemia in the treated diabetic mice. The temporary hyperglycemia was 11 ± 1 versus 19 ± 5 days (p<0.05 for the mice with full donor chimerism with transplanted islets in the renal subcapsular space versus the subcutaneous space, respectively. Cotransplantation of mesenchymal stem cell did not enhance alloislet engraftment. Full multilineage donor chimerism was associated with a higher transient expansion of CD11b+ and Gr-1+ myeloid progenitor cells and effector memory CD4 and CD8 T cells. In conclusion, full donor chimerism protected both renal subcapsular and subcutaneous allogeneic islets in this rodent transplantation model.

  20. VEGF-conjugated alginate hydrogel prompt angiogenesis and improve pancreatic islet engraftment and function in type 1 diabetes

    International Nuclear Information System (INIS)

    Yin, Nina; Han, Yongming; Xu, Hanlin; Gao, Yisen; Yi, Tao; Yao, Jiale; Dong, Li; Cheng, Dejun; Chen, Zebin

    2016-01-01

    Type 1 diabetes was a life-long disease that affected numerous people around the world. Insulin therapy has its limitations that may involve hyperglycemia and heavy burden of patient by repeated dose. Islet transplantation emerged as a promising approach to reach periodical reverse of diabetes, however, transplanted islets suffer from foreign body reaction and lack of nutrition and oxygen supply, especially in the blood-vessel-shortage subcutaneous site which was preferred by patient and surgeon. In this study, we designed and synthesized a vascular endothelial growth factor (VEGF) conjugated alginate material to encapsulate the transplanted islets via 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) reaction, and successful conjugation was confirmed by Nuclear Magnetic Resonance H1 spectrum. The best VEGF concentration (100 ng/ml) was determined by the combined studies of the mechanical property and endothelial cell growth assay. In vivo study, conjugated VEGF on alginate exhibited sustained promoting angiogenesis property after subcutaneous transplantation by histology study and islets encapsulated in this material achieved long term therapeutic effect (up to 50 days) in the diabetic mice model. In conclusion, this study establishes a simple biomaterial strategy for islet transplantation to enhance islet survival and function, which could be a feasible therapeutic alternative for type 1 diabetes. - Highlights: • We synthesized VEGF-conjugated alginate material to encapsulate the transplanted islets. • The biomaterials improve islet engraftment and function due to angiogenesis. • The biomaterials could be a strong support for cell therapy with islet transplantation in type 1 diabetes.

  1. VEGF-conjugated alginate hydrogel prompt angiogenesis and improve pancreatic islet engraftment and function in type 1 diabetes

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Nina; Han, Yongming [Department of Anatomy, Basic Medical College, Hubei University of Chinese Medicine, Wuhan, Hubei (China); Xu, Hanlin [Pharmacy Faculty, Hubei University of Chinese Medicine, Wuhan, Hubei (China); Gao, Yisen; Yi, Tao [Acupuncture and Moxibustion College, Hubei University of Chinese Medicine, Wuhan, Hubei (China); Yao, Jiale; Dong, Li; Cheng, Dejun [Basic Medical College, Hubei University of Chinese Medicine, Wuhan, Hubei (China); Chen, Zebin, E-mail: chenzebin-hbtcm@outlook.com [Acupuncture and Moxibustion College, Hubei University of Chinese Medicine/Hubei Provincial Collaborative Innovation Center of Preventive Treatment by Acupuncture and Moxibustion, Wuhan, Hubei (China)

    2016-02-01

    Type 1 diabetes was a life-long disease that affected numerous people around the world. Insulin therapy has its limitations that may involve hyperglycemia and heavy burden of patient by repeated dose. Islet transplantation emerged as a promising approach to reach periodical reverse of diabetes, however, transplanted islets suffer from foreign body reaction and lack of nutrition and oxygen supply, especially in the blood-vessel-shortage subcutaneous site which was preferred by patient and surgeon. In this study, we designed and synthesized a vascular endothelial growth factor (VEGF) conjugated alginate material to encapsulate the transplanted islets via 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) reaction, and successful conjugation was confirmed by Nuclear Magnetic Resonance H1 spectrum. The best VEGF concentration (100 ng/ml) was determined by the combined studies of the mechanical property and endothelial cell growth assay. In vivo study, conjugated VEGF on alginate exhibited sustained promoting angiogenesis property after subcutaneous transplantation by histology study and islets encapsulated in this material achieved long term therapeutic effect (up to 50 days) in the diabetic mice model. In conclusion, this study establishes a simple biomaterial strategy for islet transplantation to enhance islet survival and function, which could be a feasible therapeutic alternative for type 1 diabetes. - Highlights: • We synthesized VEGF-conjugated alginate material to encapsulate the transplanted islets. • The biomaterials improve islet engraftment and function due to angiogenesis. • The biomaterials could be a strong support for cell therapy with islet transplantation in type 1 diabetes.

  2. Oxygenated thawing and rewarming alleviate rewarming injury of cryopreserved pancreatic islets.

    Science.gov (United States)

    Komatsu, Hirotake; Barriga, Alyssa; Medrano, Leonard; Omori, Keiko; Kandeel, Fouad; Mullen, Yoko

    2017-05-06

    Pancreatic islet transplantation is an effective treatment for Type 1 diabetic patients to eliminate insulin injections; however, a shortage of donor organs hinders the widespread use. Although long-term islet storage, such as cryopreservation, is considered one of the key solutions, transplantation of cryopreserved islets is still not practical due to the extensive loss during the cryopreservation-rewarming process. We have previously reported that culturing islets in a hyperoxic environment is an effective treatment to prevent islet death from the hypoxic injury during culture. In this study, we explored the effectiveness of thawing and rewarming cryopreserved islets in a hyperoxic environment. Following cryopreservation of isolated human islets, the thawing solution and culture media were prepared with or without pre-equilibration to 50% oxygen. Thawing/rewarming and the pursuant two-day culture were performed with or without oxygenation. Short-term recovery rate, defined as the volume change during cryopreservation and thawing/rewarming, was assessed. Ischemia-associated and inflammation-associated gene expressions were examined using qPCR after the initial rewarming period. Long-term recovery rate, defined as the volume change during the two-day culture after the thawing/rewarming, was also examined. Islet metabolism and function were assessed by basal oxygen consumption rate and glucose stimulated insulin secretion after long-term recovery. Oxygenated thawing/rewarming did not alter the short-term recovery rate. Inflammation-associated gene expressions were elevated by the conventional thawing/rewarming method and suppressed by the oxygenated thawing/rewarming, whereas ischemia-associated gene expressions did not change between the thawing/rewarming methods. Long-term recovery rate experiments revealed that only the combination therapy of oxygenated thawing/rewarming and oxygenated culture alleviated islet volume loss. These islets showed higher metabolism

  3. Mesenchymal Stem Cells Enhance Allogeneic Islet Engraftment in Nonhuman Primates

    Science.gov (United States)

    Berman, Dora M.; Willman, Melissa A.; Han, Dongmei; Kleiner, Gary; Kenyon, Norman M.; Cabrera, Over; Karl, Julie A.; Wiseman, Roger W.; O'Connor, David H.; Bartholomew, Amelia M.; Kenyon, Norma S.

    2010-01-01

    OBJECTIVE To test the graft-promoting effects of mesenchymal stem cells (MSCs) in a cynomolgus monkey model of islet/bone marrow transplantation. RESEARCH DESIGN AND METHODS Cynomolgus MSCs were obtained from iliac crest aspirate and characterized through passage 11 for phenotype, gene expression, differentiation potential, and karyotype. Allogeneic donor MSCs were cotransplanted intraportally with islets on postoperative day (POD) 0 and intravenously with donor marrow on PODs 5 and 11. Recipients were followed for stabilization of blood glucose levels, reduction of exogenous insulin requirement (EIR), C-peptide levels, changes in peripheral blood T regulatory cells, and chimerism. Destabilization of glycemia and increases in EIR were used as signs of rejection; additional intravenous MSCs were administered to test the effect on reversal of rejection. RESULTS MSC phenotype and a normal karyotype were observed through passage 11. IL-6, IL-10, vascular endothelial growth factor, TGF-β, hepatocyte growth factor, and galectin-1 gene expression levels varied among donors. MSC treatment significantly enhanced islet engraftment and function at 1 month posttransplant (n = 8), as compared with animals that received islets without MSCs (n = 3). Additional infusions of donor or third-party MSCs resulted in reversal of rejection episodes and prolongation of islet function in two animals. Stable islet allograft function was associated with increased numbers of regulatory T-cells in peripheral blood. CONCLUSIONS MSCs may provide an important approach for enhancement of islet engraftment, thereby decreasing the numbers of islets needed to achieve insulin independence. Furthermore, MSCs may serve as a new, safe, and effective antirejection therapy. PMID:20622174

  4. The Role of Tissue-Resident Donor T Cells in Rejection of Clinical Face Transplants

    Science.gov (United States)

    2017-10-01

    cells contribute to VCA rejection, and that pathogenic T cells (both donor and recipient-derived) are detectable in blood during rejection to serve as...AWARD NUMBER: W81XWH-16-1-0760 TITLE: The role of tissue-resident donor T cells in rejection of clinical face transplants PRINCIPAL...AND SUBTITLE The role of tissue-resident donor T cells in rejection of clinical face transplants 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-16-1

  5. A New Method for Generating Insulin-Secreting Cells from Human Pancreatic Epithelial Cells After Islet Isolation Transformed by NeuroD1

    Science.gov (United States)

    Shimoda, Masayuki; Chen, Shuyuan; Noguchi, Hirofumi; Takita, Morihito; Sugimoto, Koji; Itoh, Takeshi; Chujo, Daisuke; Iwahashi, Shuichi; Naziruddin, Bashoo; Levy, Marlon F.

    2014-01-01

    Abstract The generation of insulin-secreting cells from nonendocrine pancreatic epithelial cells (NEPEC) has been demonstrated for potential clinical use in the treatment of diabetes. However, previous methods either had limited efficacy or required viral vectors, which hinder clinical application. In this study, we aimed to establish an efficient method of insulin-secreting cell generation from NEPEC without viral vectors. We used nonislet fractions from both research-grade human pancreata from brain-dead donors and clinical pancreata after total pancreatectomy with autologous islet transplantation to treat chronic pancreatitis. It is of note that a few islets could be mingled in the nonislet fractions, but their influence could be limited. The NeuroD1 gene was induced into NEPEC using an effective triple lipofection method without viral vectors to generate insulin-secreting cells. The differentiation was promoted by adding a growth factor cocktail into the culture medium. Using the research-grade human pancreata, the effective method showed high efficacy in the differentiation of NEPEC into insulin-positive cells that secreted insulin in response to a glucose challenge and improved diabetes after being transplanted into diabetic athymic mice. Using the clinical pancreata, similar efficacy was obtained, even though those pancreata suffered chronic pancreatitis. In conclusion, our effective differentiation protocol with triple lipofection method enabled us to achieve very efficient insulin-secreting cell generation from human NEPEC without viral vectors. This method offers the potential for supplemental insulin-secreting cell transplantation for both allogeneic and autologous islet transplantation. PMID:24845703

  6. Personality traits and clinical/biochemical course in the first year after kidney transplant.

    Science.gov (United States)

    Thomas, Caroline Venzon; de Castro, Elisa Kern; Antonello, Ivan Carlos Ferreira

    2016-10-01

    The relationship between personality and health is frequently studied in scientific research. This study investigated the clinical/biochemical course of kidney transplant patients based on personality traits. A longitudinal study assessed 114 kidney transplant patients (men = 68 and women = 46) with an average age of 47.72 years (SD = 11.4). Personality was evaluated using the Brazilian Factorial Personality Inventory (BFP/Big Five Model). Clinical variables were analyzed based on patient charts (estimated glomerular filtration rate (eGFR), hypertension, acute rejection, infection, graft loss, and death). Personality types were assessed by hierarchical cluster analysis. Two groups with personality types were differentiated by psychological characteristics: Cluster 1 - average neuroticism, high surgency, agreeableness and conscientiousness, and low openness; Cluster 2 - high neuroticism, average surgency and agreeableness, average conscientiousness, and low openness. There was no statistically significant difference between the clusters in terms of hypertension, acute infection, graft loss, death, and Human Leukocyte Antigen (HLA) I and II panel reactive antibodies. eGFR was associated with the personality types. Cluster 2 was associated with a better renal function in the 9-month follow-up period after kidney transplantation. In this study, patients from Cluster 2 exhibited higher eGFR 9 months after the transplant procedure compared to those from Cluster 1. Monitoring these patients over a longer period may provide a better understanding of the relationship between personality traits and clinical course during the post-transplant period.

  7. Effect of total lymphoid irradiation on pancreatic islet xenograft survival in rats

    International Nuclear Information System (INIS)

    Nakajima, Y.; Lie, T.S.; Nakauo, H.; Nakagawa, K.; Segawa, M.

    1984-01-01

    Before transplantation of Syrian hamster pancreatic islet xenografts to diabetic rats the recipients received total lymphatic system irradiation and cyclosporin A treatment after transplantation for immunosuppression. The xenograft survival times were measured and the rat anti-hamster lymphocytotoxic titers were determined by 51 Cr release assay

  8. Effect of total lymphoid irradiation on pancreatic islet xenograft survival in rats

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Y; Lie, T S [Bonn Univ. (Germany, F.R.). Chirurgische Klinik und Poliklinik; Nakauo, H; Nakagawa, K; Segawa, M [Nara Women' s Univ. (Japan). Dept. of Physics

    1984-01-01

    Before transplantation of Syrian hamster pancreatic islet xenografts to diabetic rats the recipients received total lymphatic system irradiation and cyclosporin A treatment after transplantation for immunosuppression. The xenograft survival times were measured and the rat anti-hamster lymphocytotoxic titers were determined by /sup 51/Cr release assay.

  9. The Peri-islet Basement Membrane, a Barrier to Infiltrating Leukocytes in Type 1 Diabetes in Mouse and Human

    DEFF Research Database (Denmark)

    Korpos, Eva; Kadri, Nadir; Kappelhoff, Reinhild

    2013-01-01

    We provide the first comprehensive analysis of the extracellular matrix (ECM) composition of peri-islet capsules, composed of the peri-islet basement membrane (BM) and subjacent interstitial matrix (IM), in development of type 1 diabetes in NOD mice and in human type 1 diabetes. Our data demonstr...... IM are reconstituted once inflammation subsides, indicating that the peri-islet BM-producing cells are not lost due to the inflammation, which has important ramifications to islet transplantation studies.......We provide the first comprehensive analysis of the extracellular matrix (ECM) composition of peri-islet capsules, composed of the peri-islet basement membrane (BM) and subjacent interstitial matrix (IM), in development of type 1 diabetes in NOD mice and in human type 1 diabetes. Our data...... demonstrate global loss of peri-islet BM and IM components only at sites of leukocyte infiltration into the islet. Stereological analyses reveal a correlation between incidence of insulitis and the number of islets showing loss of peri-islet BM versus islets with intact BMs, suggesting that leukocyte...

  10. Pulmonary nodules and masses in lung transplant recipients: clinical and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Morla, Olivier; Liberge, Renan; Arrigoni, Pierre Paul; Frampas, Eric [Service de Radiologie Centrale, C.H.U. Hotel Dieu, Nantes (France)

    2014-09-15

    The purpose of this study was to review the clinical and CT findings of pulmonary nodules and masses in lung transplant recipients and to determine distinguishing features among the various aetiologies. This retrospective study included 106 lung transplant recipients who had a chest CT performed over a 7-year period in a single institution. Twenty-four cases of pulmonary nodules and masses were observed on CT. Among the single lesions, three (50 %) were due to infections, one (17 %) to organizing pneumonia, and two (33 %) remained of undetermined origin. Among the multiple lesions, 14 (78 %) were due to infection, three to post-transplant lymphoproliferative disorder (17 %), and one to bronchogenic carcinoma (5 %). The two main microorganisms were P. aeruginosa and Aspergillus spp. Among 12 solid nodules > 1 cm, four (33 %) were due to malignancy: three post-transplant lymphoproliferative disorders (25 %), and one bronchogenic carcinoma (8 %). Among five cavitary nodules four (80 %) were due to aspergillosis. Infection is the most frequent aetiology of pulmonary nodules and masses in lung transplant recipients, but other causes such as post-transplant lymphoproliferative disorder, bronchogenic carcinoma, or organizing pneumonia should be considered. (orig.)

  11. Effect of gamma-irradiation on mouse pancreatic islet-allograft survival

    International Nuclear Information System (INIS)

    Kanai, T.; Porter, J.; Gotoh, M.; Monaco, A.P.; Maki, T.

    1989-01-01

    Elimination or inactivation of lymphoid tissue in the pancreatic islet preparation achieves prolongation of islet-allograft survival. In this study we examined the effect of gamma-irradiation on mouse islet-allograft survival. In a B6AF1 isograft model, irradiation up to 2400 rad did not induce deterioration of islet function over 200 days, but greater doses caused cessation of graft function between 83 and 186 days. When DBA/2 crude islets were transplanted into B6AF1 recipients, all nonirradiated allografts were acutely rejected. Marked prolongation of allograft survival was achieved by islet irradiation with doses between 800 and 12,000 rad. With higher doses, significant numbers of allografts survived beyond the controls, but many lost function between 78 and 180 days, with none surviving greater than 200 days. Irradiation with 16,000 rad caused acute radiation damage. Because most secondary islet allografts in recipient mice that lost primary islet-graft function between 84 and 195 days survived greater than 100 days, late functional loss was probably due to the radiation injury. Combined use of recipient treatment with cyclosporin A and graft irradiation (2400 rad) achieved prolongation of DBA/2 islets in B6AF1 mice

  12. Impact of Pancreatic Rat Islet Density on Cell Survival during Hypoxia

    Directory of Open Access Journals (Sweden)

    A. Rodriguez-Brotons

    2016-01-01

    Full Text Available In bioartificial pancreases (BP, the number of islets needed to restore normoglycaemia in the diabetic patient is critical. However, the confinement of a high quantity of islets in a limited space may impact islet survival, particularly in regard to the low oxygen partial pressure (PO2 in such environments. The aim of the present study was to evaluate the impact of islet number in a confined space under hypoxia on cell survival. Rat islets were seeded at three different concentrations (150, 300, and 600 Islet Equivalents (IEQ/cm2 and cultured in normal atmospheric pressure (160 mmHg as well as hypoxic conditions (15 mmHg for 24 hours. Cell viability, function, hypoxia-induced changes in gene expression, and cytokine secretion were then assessed. Notably, hypoxia appeared to induce a decrease in viability and increasing islet density exacerbated the observed increase in cellular apoptosis as well as the loss of function. These changes were also associated with an increase in inflammatory gene transcription. Taken together, these data indicate that when a high number of islets are confined to a small space under hypoxia, cell viability and function are significantly impacted. Thus, in order to improve islet survival in this environment during transplantation, oxygenation is of critical importance.

  13. Human embryonic stem cell derived islet progenitors mature inside an encapsulation device without evidence of increased biomass or cell escape.

    Science.gov (United States)

    Kirk, Kaitlyn; Hao, Ergeng; Lahmy, Reyhaneh; Itkin-Ansari, Pamela

    2014-05-01

    There are several challenges to successful implementation of a cell therapy for insulin dependent diabetes derived from human embryonic stem cells (hESC). Among these are development of functional insulin producing cells, a clinical delivery method that eliminates the need for chronic immunosuppression, and assurance that hESC derived tumors do not form in the patient. We and others have shown that encapsulation of cells in a bilaminar device (TheraCyte) provides immunoprotection in rodents and primates. Here we monitored human insulin secretion and employed bioluminescent imaging (BLI) to evaluate the maturation, growth, and containment of encapsulated islet progenitors derived from CyT49 hESC, transplanted into mice. Human insulin was detectable by 7 weeks post-transplant and increased 17-fold over the course of 8 weeks, yet during this period the biomass of encapsulated cells remained constant. Remarkably, by 20 weeks post-transplant encapsulated cells secreted sufficient levels of human insulin to ameliorate alloxan induced diabetes. Further, bioluminescent imaging revealed for the first time that hESCs remained fully contained in encapsulation devices for up to 150 days, the longest period tested. Collectively, the data suggest that encapsulated hESC derived islet progenitors hold great promise as an effective and safe cell replacement therapy for insulin dependent diabetes. Copyright © 2014. Published by Elsevier B.V.

  14. Sustained beta-cell dysfunction but normalized islet mass in aged thrombospondin-1 deficient mice.

    Directory of Open Access Journals (Sweden)

    Carl Johan Drott

    Full Text Available Pancreatic islet endothelial cells have in recent years been shown to support beta-cell mass and function by paracrine interactions. Recently, we identified an islets endothelial-specific glycoprotein, thrombospondin-1 (TSP-1, that showed to be of importance for islet angiogenesis and beta-cell function in young mice. The present study aimed to investigate long-term consequences for islet morphology and beta-cell function of TSP-1 deficiency. Islet and beta-cell mass were observed increased at 10-12 weeks of age in TSP-1 deficient mice, but were normalized before 16 weeks of age when compared to wild-type controls. Islet vascularity was normal in 10-12 and 16-week-old TSP-1 deficient animals, whereas islets of one-year-old animals lacking TSP-1 were hypervascular. Beta-cell dysfunction in TSP-1 deficient animals was present at similar magnitudes between 10-12 and 52 weeks of age, as evaluated by glucose tolerance tests. The insulin secretion capacity in vivo of islets in one-year-old TSP-1 deficient animals was only ∼15% of that in wild-type animals. Using a transplantation model, we reconstituted TSP-1 in adult TSP-deficient islets. In contrast to neonatal TSP-1 deficient islets that we previously reported to regain function after TSP-1 reconstitution, adult islets failed to recover. We conclude that TSP-1 deficiency in islets causes changing vascular and endocrine morphological alterations postnatally, but is coupled to a chronic beta-cell dysfunction. The beta-cell dysfunction induced by TSP-1 deficiency is irreversible if not substituted early in life.

  15. Posterior reversible encephalopathy syndrome in liver transplant patients: clinical presentation, risk factors and initial management.

    Science.gov (United States)

    Cruz, R J; DiMartini, A; Akhavanheidari, M; Iacovoni, N; Boardman, J F; Donaldson, J; Humar, A; Bartynski, W S

    2012-08-01

    Posterior reversible encephalopathy syndrome (PRES) is an uncommon but well-known complication after transplantation diagnosed by characteristic radiological features. As limited data on this complex syndrome exist we sought to better define the incidence, clinical presentation and risk factors for PRES in liver transplant (LTx) patients. We conducted a retrospective analysis of 1923 adult LTx recipients transplanted between 2000 and 2010. PRES was diagnosed radiologically in 19 patients (1%), with 84% of cases occurring within 3 months post-LTX. We compared this cohort of PRES patients to 316 other LTx recipients also requiring radiographic imaging within 3 months after LTx for neurological symptoms. Seizure was the most common clinical manifestation in the PRES group (88% vs. 16%, pliver disease and infection/sepsis. These factors may be related to a common pathway of vascular dysregulation/damage that appears to characterize this complex syndrome. Intracranial bleeding and seizures may be the end result of these phenomena. The relationship of these associated factors to the hypothesized pathophysiology of PRES is discussed. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

  16. Sleep disruption in hematopoietic cell transplantation recipients: prevalence, severity, and clinical management.

    Science.gov (United States)

    Jim, Heather S L; Evans, Bryan; Jeong, Jiyeon M; Gonzalez, Brian D; Johnston, Laura; Nelson, Ashley M; Kesler, Shelli; Phillips, Kristin M; Barata, Anna; Pidala, Joseph; Palesh, Oxana

    2014-10-01

    Sleep disruption is common among hematopoietic cell transplant (HCT) recipients, with over 50% of recipients experiencing sleep disruption pre-transplant, with up to 82% of patients experiencing moderate to severe sleep disruption during hospitalization for transplant and up to 43% after transplant. These rates of sleep disruption are substantially higher than what we see in the general population. Although sleep disruption can be distressing to patients and contribute to diminished quality of life, it is rarely discussed during clinical visits. The goal of the current review is to draw attention to sleep disruption and disorders (ie, insomnia, obstructive sleep apnea, restless legs syndrome) as a clinical problem in HCT in order to facilitate patient education, intervention, and research. We identified 35 observational studies published in the past decade that examined sleep disruption or disorders in HCT. Most studies utilized a single item measure of sleep, had small sample size, and included heterogeneous samples of patients. Six studies of the effects of psychosocial and exercise interventions on sleep in HCT have reported no significant improvements. These results highlight the need for rigorous observational and interventional studies of sleep disruption and disorders in HCT recipients.. Copyright © 2014 American Society for Blood and Marrow Transplantation. All rights reserved.

  17. Return to work after thoracic organ transplantation in a clinically-stable population.

    Science.gov (United States)

    Petrucci, Lucia; Ricotti, Susanna; Michelini, Ilaria; Vitulo, Patrizio; Oggionni, Tiberio; Cascina, Alessandro; D'Armini, Andrea M; Goggi, Claudio; Campana, Carlo; Viganò, Mario; Dalla-Toffola, Elena; Tinelli, Carmine; Klersy, Catherine

    2007-11-01

    To evaluate the rate of return to work after transplantation and its determinants in a clinically-stable population of patients transplanted and followed-up at a single institution in Italy. 151 thoracic organ transplant recipients (72 lung, 79 heart) were examined. Patients were asked about daily activities, level of education, employment and clinical condition. A six-minute walking test was performed with measurement of dyspnoea using the Borg scale. Quality of Life was evaluated with the SF-36 and GHQ questionnaires. Before transplantation 131 patients (87%), (70 heart and 61 lung) worked. After transplantation, 51 patients (39%) went back to work and 3 more started working. We found that younger age, a better quality of life (mainly in the mental domain), having had an occupation previously (particularly as an entrepreneur/freelancer), and having been off work for less than 24 months, were independent predictors of return to work. Considering their good, objective and subjective, functional status, some patients who could have returned to work, chose not to. Identifying factors which affect return to work might help health professionals to adopt the best course of treatment and psychological support in order to fulfil this goal; however, return to work should not be considered as the only expression of a patient's real psychophysical condition.

  18. Prospective clinical testing of regulatory dendritic cells (DCreg in organ transplantation

    Directory of Open Access Journals (Sweden)

    ANGUS W THOMSON

    2016-01-01

    Full Text Available Dendritic cells (DC are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering the incidence and severity of rejection and reducing patients’ dependence on anti-rejection drugs. Generation of donor- or recipient-derived DCreg that suppress T cell responses and prolong transplant survival in rodents or non-human primates has been well-described. Recently, good manufacturing practice (GMP-grade DCreg have been produced at our Institution for prospective use in human organ transplantation. We briefly review experience of regulatory immune therapy in organ transplantation and describe our experience generating and characterizing human monocyte-derived DCreg. We propose a phase I/II safety study in which the influence of donor-derived DCreg combined with conventional immunosuppression on subclinical and clinical rejection and host alloimmune responses will be examined in detail.

  19. Microcapsules with intrinsic barium radiopacity for immunoprotection and X-ray/CT imaging of pancreatic islet cells.

    Science.gov (United States)

    Arifin, Dian R; Manek, Sameer; Call, Emma; Arepally, Aravind; Bulte, Jeff W M

    2012-06-01

    Microencapsulation is a commonly used technique for immunoprotection of engrafted therapeutic cells. We investigated a library of capsule formulations to determine the most optimal formulation for pancreatic beta islet cell transplantation, using barium as the gelating ion and clinical-grade protamine sulfate (PS) as a new cationic capsule cross-linker. Barium-gelated alginate/PS/alginate microcapsules (APSA, diameter = 444 ± 21 μm) proved to be mechanically stronger and supported a higher cell viability as compared to conventional alginate/poly-l-lysine/alginate (APLLA) capsules. Human pancreatic islets encapsulated inside APSA capsules, gelated with 20 mm barium as optimal concentration, exhibited a sustained morphological integrity, viability, and functionality for at least 3-4 weeks in vitro, with secreted human C-peptide levels of 0.2-160 pg/ml/islet. Unlike APLLA capsules that are gelled with calcium, barium-APSA capsules are intrinsically radiopaque and, when engrafted into mice, could be readily imaged in vivo with micro-computed tomography (CT). Without the need of adding contrast agents, these capsules offer a clinically applicable alternative for simultaneous immunoprotection and real-time, non-invasive X-ray/CT monitoring of engrafted cells during and after in vivo administration. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Retention of gene expression in porcine islets after agarose encapsulation and long-term culture

    Energy Technology Data Exchange (ETDEWEB)

    Dumpala, Pradeep R., E-mail: pdumpala@rixd.org [The Rogosin Institute – Xenia Division, 740 Birch Road, Xenia, OH 45385 (United States); Holdcraft, Robert W.; Martis, Prithy C.; Laramore, Melissa A. [The Rogosin Institute – Xenia Division, 740 Birch Road, Xenia, OH 45385 (United States); Parker, Thomas S.; Levine, Daniel M. [The Rogosin Institute, 505 East 70th Street, New York, NY 10021 (United States); Smith, Barry H. [The Rogosin Institute, 505 East 70th Street, New York, NY 10021 (United States); NewYork-Presbyterian Hospital, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021 (United States); Gazda, Lawrence S. [The Rogosin Institute – Xenia Division, 740 Birch Road, Xenia, OH 45385 (United States)

    2016-08-05

    Agarose encapsulation of porcine islets allows extended in vitro culture, providing ample time to determine the functional capacity of the islets and conduct comprehensive microbiological safety testing prior to implantation as a treatment for type 1 diabetes mellitus. However, the effect that agarose encapsulation and long-term culture may have on porcine islet gene expression is unknown. The aim of the present study was to compare the transcriptome of encapsulated porcine islets following long-term in vitro culture against free islets cultured overnight. Global gene expression analysis revealed no significant change in the expression of 98.47% of genes. This indicates that the gene expression profile of free islets is highly conserved following encapsulation and long-term culture. Importantly, the expression levels of genes that code for critical hormones secreted by islets (insulin, glucagon, and somatostatin) as well as transcripts encoding proteins involved in their packaging and secretion are unchanged. While a small number of genes known to play roles in the insulin secretion and insulin signaling pathways are differentially expressed, our results show that overall gene expression is retained following islet isolation, agarose encapsulation, and long-term culture. - Highlights: • Effect of agarose encapsulation and 8 week culture on porcine islets was analyzed. • Transcriptome analysis revealed no significant change in a majority (98%) of genes. • Agarose encapsulation allows for long-term culture of porcine islets. • Islet culture allows for functional and microbial testing prior to clinical use.

  1. Retention of gene expression in porcine islets after agarose encapsulation and long-term culture

    International Nuclear Information System (INIS)

    Dumpala, Pradeep R.; Holdcraft, Robert W.; Martis, Prithy C.; Laramore, Melissa A.; Parker, Thomas S.; Levine, Daniel M.; Smith, Barry H.; Gazda, Lawrence S.

    2016-01-01

    Agarose encapsulation of porcine islets allows extended in vitro culture, providing ample time to determine the functional capacity of the islets and conduct comprehensive microbiological safety testing prior to implantation as a treatment for type 1 diabetes mellitus. However, the effect that agarose encapsulation and long-term culture may have on porcine islet gene expression is unknown. The aim of the present study was to compare the transcriptome of encapsulated porcine islets following long-term in vitro culture against free islets cultured overnight. Global gene expression analysis revealed no significant change in the expression of 98.47% of genes. This indicates that the gene expression profile of free islets is highly conserved following encapsulation and long-term culture. Importantly, the expression levels of genes that code for critical hormones secreted by islets (insulin, glucagon, and somatostatin) as well as transcripts encoding proteins involved in their packaging and secretion are unchanged. While a small number of genes known to play roles in the insulin secretion and insulin signaling pathways are differentially expressed, our results show that overall gene expression is retained following islet isolation, agarose encapsulation, and long-term culture. - Highlights: • Effect of agarose encapsulation and 8 week culture on porcine islets was analyzed. • Transcriptome analysis revealed no significant change in a majority (98%) of genes. • Agarose encapsulation allows for long-term culture of porcine islets. • Islet culture allows for functional and microbial testing prior to clinical use.

  2. Relevance of MICA and other non-HLA antibodies in clinical transplantation.

    Science.gov (United States)

    Sumitran-Holgersson, Suchitra

    2008-10-01

    The clinical importance of HLA-specific antibodies for organ allograft outcome is well established. In the past few years, there has been an increasing interest in non-HLA antigens as targets of injury in organ transplant recipients. This increased interest has been spurred by the fact that HLA-identical kidney transplants also undergo immunological rejections. Polymorphisms within non-HLA genes associated with evoking an immune response to alloantigens are currently being studied for their association with transplant outcome. Non-HLA antigens, such as the polymorphic MHC class I-related chain A (MICA), expressed on endothelial cells have been implicated in the pathogenesis of hyperacute, acute and chronic organ allograft rejections. Use of endothelial cells as targets may clarify the specificities of other clinically relevant non-HLA antibodies in graft rejections. This review summarizes past and current knowledge of the clinical importance and specificities of non-HLA antibodies, and mechanisms by which these antibodies may contribute to graft destruction in clinical transplantation. The aims of current research into the role of non-HLA antigens and their genetics in predicting outcome are to develop an improved insight into the basic science of transplantation and to develop a risk or prognostic index for use in the clinical setting. Non-HLA antibody responses are receiving increasing interest in acute and chronic rejection and specificity, affinity, and pathogenicity need to be investigated to estimate their contribution. Undoubtedly, this will continue to be an area of interest in terms of fully understanding the role of non-HLA antigens as targets of immune-mediated injury and the potential for clinical intervention.

  3. Perceived Workforce Challenges among Clinical Social Workers in Hematopoietic Cell Transplantation Programs.

    Science.gov (United States)

    Stickney Ferguson, Stacy; Randall, Jill; Dabney, Jane; Kalbacker, Marion E; Boyle, Nancy; Thao, Viengneesee; Murphy, Elizabeth A; Denzen, Ellen M

    2018-05-01

    Clinical social workers are psychosocial care experts who provide interventions that aim to address the emotional, relational, financial, and logistical challenges that arise throughout the hematopoietic cell transplantation (HCT) treatment and recovery process. Interventions that contribute to better patient outcomes can include cognitive behavioral therapy and counseling for adaptation to illness, family planning for 24/7 caregiver availability and strategies to support patient activities of daily living, instruction on guided imagery and relaxation techniques for symptom management and to decrease anxiety, psychoeducation on the treatment trajectory, and linkage with financial resources. A Social Work Workforce Group (SWG) was established through the System Capacity Initiative, led by the National Marrow Donor Program/Be The Match, to characterize the current social work workforce capacity and challenges. The SWG conducted a web-based survey of HCT clinical social workers in the United States. The response rate was 57% (n = 90), representing 76 transplant centers. Survey results indicated that the clinical social worker role and scope of practice varies significantly between centers; less than half of respondents reported that their clinical social work expertise was used to its fullest potential. With an estimated 3-fold increase in HCT patient volume by 2020, the need for specialized psychosocial health services will increase. The SWG makes recommendations to build capacity for the psychosocial care of HCT patients and to more fully integrate the social worker as a core member of the HCT team. The SWG created a Blood and Marrow Transplant (BMT) Clinical Social Worker role description that can be used by transplant centers to educate healthcare professionals, benchmark utilization of clinical social workers, and improve comprehensive psychosocial health programs. Copyright © 2018 The American Society for Blood and Marrow Transplantation. Published by

  4. Sleep Disruption in Hematopoietic Cell Transplant Recipients: Prevalence, Severity, and Clinical Management

    Science.gov (United States)

    Jim, Heather S.L.; Evans, Bryan; Jeong, Jiyeon M.; Gonzalez, Brian D.; Johnston, Laura; Nelson, Ashley M.; Kesler, Shelli; Phillips, Kristin M.; Barata, Anna; Pidala, Joseph; Palesh, Oxana

    2014-01-01

    Sleep disruption is common among hematopoietic cell transplant (HCT) recipients, with over 50% of patients experiencing sleep disruption pre-transplant, up to 82% experiencing moderate to severe sleep disruption during hospitalization for transplant, and up to 43% in the post-transplant period. These rates of sleep disruption are substantially higher than the general population. Although sleep disruption can be distressing to patients and contribute to diminished quality of life, it is rarely discussed during clinical visits. The goal of the current review is to draw attention to sleep disruption as a clinical problem in HCT in order to facilitate patient education, intervention, and research. The review opens with a discussion of sleep disruption measurement and clinical diagnosis of sleep disorders. An overview of the prevalence, severity, and chronicity of sleep disruption and disorders in patients receiving HCT follows. Current evidence regarding sociodemographic and clinical predictors of sleep disruption and disorders is summarized. The review concludes with suggestions for behavioral and pharmacologic management of sleep disruption and disorders as well as directions for future research. PMID:24747335

  5. Frequency and clinical predictors of coronary artery disease in chronic renal failure renal transplant candidates.

    Science.gov (United States)

    de Albuquerque Seixas, Emerson; Carmello, Beatriz Leone; Kojima, Christiane Akemi; Contti, Mariana Moraes; Modeli de Andrade, Luiz Gustavo; Maiello, José Roberto; Almeida, Fernando Antonio; Martin, Luis Cuadrado

    2015-05-01

    Cardiovascular diseases are major causes of mortality in chronic renal failure patients before and after renal transplantation. Among them, coronary disease presents a particular risk; however, risk predictors have been used to diagnose coronary heart disease. This study evaluated the frequency and importance of clinical predictors of coronary artery disease in chronic renal failure patients undergoing dialysis who were renal transplant candidates, and assessed a previously developed scoring system. Coronary angiographies conducted between March 2008 and April 2013 from 99 candidates for renal transplantation from two transplant centers in São Paulo state were analyzed for associations between significant coronary artery diseases (≥70% stenosis in one or more epicardial coronary arteries or ≥50% in the left main coronary artery) and clinical parameters. Univariate logistic regression analysis identified diabetes, angina, and/or previous infarction, clinical peripheral arterial disease and dyslipidemia as predictors of coronary artery disease. Multiple logistic regression analysis identified only diabetes and angina and/or previous infarction as independent predictors. The results corroborate previous studies demonstrating the importance of these factors when selecting patients for coronary angiography in clinical pretransplant evaluation.

  6. Clinical impact of pre-transplant gut microbial diversity on outcomes of allogeneic hematopoietic stem cell transplantation.

    Science.gov (United States)

    Doki, Noriko; Suyama, Masahiro; Sasajima, Satoshi; Ota, Junko; Igarashi, Aiko; Mimura, Iyo; Morita, Hidetoshi; Fujioka, Yuki; Sugiyama, Daisuke; Nishikawa, Hiroyoshi; Shimazu, Yutaka; Suda, Wataru; Takeshita, Kozue; Atarashi, Koji; Hattori, Masahira; Sato, Eiichi; Watakabe-Inamoto, Kyoko; Yoshioka, Kosuke; Najima, Yuho; Kobayashi, Takeshi; Kakihana, Kazuhiko; Takahashi, Naoto; Sakamaki, Hisashi; Honda, Kenya; Ohashi, Kazuteru

    2017-09-01

    Post-transplant microbial diversity in the gastrointestinal tract is closely associated with clinical outcomes following allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, little is known about the impact of the fecal microbiota before allo-HSCT. We analyzed fecal samples approximately 2 weeks before conditioning among 107 allo-HSCT recipients between 2013 and 2015. Microbial analysis was performed using 16S rRNA gene sequencing. Operational taxonomic unit-based microbial diversity was estimated by calculating the Shannon index. Patients were classified into three groups based on the diversity index: low (3) diversity (18 (16.8%), 48 (44.9%), and 41 (38.3%) patients, respectively). There were no significant differences in the 20-month overall survival, cumulative incidence of relapse, and non-relapse mortality among three groups. The cumulative incidence of grade II to IV acute graft-versus-host disease (aGVHD) was similar among the three groups (low 55.6%; intermediate 35.4%; high 48.8%, p = 0.339, at day 100). Furthermore, we found no differences in the cumulative incidence of grade II to IV acute gastrointestinal GVHD among the three groups (low 38.9%; intermediate 21.3%; high 24.4%, p = 0.778, at day 100). Regarding the composition of microbiota before allo-HSCT, aGVHD patients showed a significantly higher abundance of phylum Firmicutes (p strategy to prevent aGVHD.

  7. Clinical Features of Kidney Transplant Recipients Admitted to the Intensive Care Unit.

    Science.gov (United States)

    Freitas, Flávio Geraldo Rezende; Lombardi, Fábio; Pacheco, Eduardo Souza; Sandes-Freitas, Tainá Veras de; Viana, Laila Almeida; Junior, Hélio Tedesco-Silva; Medina-Pestana, José Osmar; Bafi, Antônio Tonete; Machado, Flavia Ribeiro

    2018-03-01

    There is a paucity of data regarding the complications in kidney transplant patients who may require intensive care unit (ICU) management, despite being the most common solid organ transplant worldwide. To identify the main reasons for ICU admission and to determine the factors associated with hospital mortality in kidney transplant recipients. This single-center retrospective cohort study was conducted between September 2013 and June 2014, including all consecutive kidney transplant patients requiring ICU admission. We collected data on patient demographics, transplant characteristics, clinical data, and prognostic scores. The independent determinants of hospital mortality were identified by multiple logistic regression analysis. We also assessed the performance of Simplified Acute Physiology Score 3 (SAPS 3) and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores. We analyzed data from 413 patients, the majority of whom were admitted late after renal transplantation (1169 days; 63-3003 days). The main reason for admission was sepsis (33.2%), followed by cardiovascular disease (16%). Age (odds ratio [OR] 1.05, confidence interval [CI], 1.01-1.09), SAPS 3 score (OR 1.04, CI, 1.01-1.08), the need for mechanical ventilation (OR 26.47, CI, 10.30-68.08), and vasopressor use (OR 3.34, CI, 1.37-8.13) were independently associated with hospital mortality. The performance of SAPS 3 and APACHE II scores was poor in this population and overestimated the mortality rates. Sepsis was the main reason for ICU admission in kidney transplant recipients, followed by cardiovascular disease. Age and disease severity were associated with hospital mortality.

  8. Cartilage Repair With Autologous Bone Marrow Mesenchymal Stem Cell Transplantation: Review of Preclinical and Clinical Studies.

    Science.gov (United States)

    Yamasaki, Shinya; Mera, Hisashi; Itokazu, Maki; Hashimoto, Yusuke; Wakitani, Shigeyuki

    2014-10-01

    Clinical trials of various procedures, including bone marrow stimulation, mosaicplasty, and autologous chondrocyte implantation, have been explored to treat articular cartilage defects. However, all of them have some demerits. We focused on autologous culture-expanded bone marrow mesenchymal stem cells (BMSC), which can proliferate without losing their capacity for differentiation. First, we transplanted BMSC into the defective articular cartilage of rabbit and succeeded in regenerating osteochondral tissue. We then applied this transplantation in humans. Our previous reports showed that treatment with BMSC relieves the clinical symptoms of chondral defects in the knee and elbow joint. We investigated the efficacy of BMSC for osteoarthritic knee treated with high tibial osteotomy, by comparing 12 BMSC-transplanted patients with 12 cell-free patients. At 16-month follow-up, although the difference in clinical improvement between both groups was not significant, the arthroscopic and histological grading score was better in the cell-transplanted group. At the over 10-year follow-up, Hospital for Special Surgery knee scores improved to 76 and 73 in the BMSC-transplanted and cell-free groups, respectively, which were better than preoperative scores. Additionally, neither tumors nor infections were observed in all patients, and in the clinical study, we have never observed hypertrophy of repaired tissue, thereby guaranteeing the clinical safety of this therapy. Although we have never observed calcification above the tidemark in rabbit model and human histologically, the repair cartilage was not completely hyaline cartilage. To elucidate the optimum conditions for cell therapy, other stem cells, culture conditions, growth factors, and gene transfection methods should be explored.

  9. Enhancing engraftment of islets using perioperative sodium 4-phenylbutyrate.

    Science.gov (United States)

    Hsu, Brend Ray-Sea; Chen, Szu-Tah; Fu, Shin-Huei

    2006-12-20

    Primary nonfunction (PNF) adversely impacts islet transplantation. In addition to determining whether sodium 4-phenylbutyrate (4-SPB), an anti-inflammatory agent, reduces PNF, this study investigates how 4-SPB affects PNF. Streptozotocin-induced diabetic C57BL/6 mice, that received 75 syngeneic islets underneath left subrenal space, were fed twice daily of either 4-SPB at 500 mg/kg body weight or isotonic saline (NaCl) from 2 days before through 7 days after transplantation. The graft was removed at days 3, 10 and 84 following transplantation. At 68 h following transplantation, serum levels of interleukin-1beta (IL-1beta) were 2.2+/-0.4 and 0.4+/-0.2 pmol/L (n=6, p<0.005) for NaCl and 4-SPB groups, respectively. Graft genetic expression of IL-1beta was significantly suppressed in 4-SPB group (p<0.01). At day 10, the blood glucose levels were 22.7+/-1.0 and 17.1+/-1.7 mmol/L (n=12, p<0.05) and graft insulin contents (IC) were 35.0+/-8.3 and 107.6+/-29.7 pmol (n=12, p<0.05) for NaCl and 4-SPB groups, respectively. Moreover, the 4-SPB group had a shorter temporary hyperglycemia (15+/-2, n=21 vs. 25+/-2 days, n=19, p=0.001) and a higher cumulative cure rate of diabetes (p<0.001) than the NaCl group. In-vitro studies indicated that 4-SPB did not impact the islets function. These experimental results demonstrated that perioperative administration of 4-SPB decreased serum level and graft genetic expression of IL-1beta and attenuated PNF, which enhanced islet engraftment in a syngeneic transplantation mouse model.

  10. [Comparison of clinical and histological diagnosis in kidney post-transplantation period].

    Science.gov (United States)

    de Castro, M C; Chocair, P R; Saldanha, L B; Nahas, W; Arap, S; Sabbaga, E; Ianhez, L E

    1998-01-01

    To assess the agreement between clinical and histopathological diagnosis in a renal transplantation center, 40 episodes of acute renal failure were studied. Kidney biopsies were performed at the moment that a clinical diagnosis was made by the staff. Nineteen episodes of acute tubular necrosis (ATN), eighteen episodes of acute cellular rejection (ACR), 2 humoral rejections and 1 acute cyclosporin nephrotoxicity episodes were diagnosed. ATN episodes were confirmed by renal biopsy in 84.21%, ACR episodes in 83.33%, humoral rejections in 100%. Renal biopsy showed ATN in the occurrence of clinical cyclosporin nephrotoxicity. Total agreement was 82.5%. There is a good relationship between clinical and histopathological diagnosis in the post-transplantation period. Diagnostic mistakes occurred mainly when oliguria was present.

  11. Experimental evidence for the origin of ductal-type adenocarcinoma from the islets of Langerhans.

    OpenAIRE

    Pour, P. M.; Weide, L.; Liu, G.; Kazakoff, K.; Scheetz, M.; Toshkov, I.; Ikematsu, Y.; Fienhold, M. A.; Sanger, W.

    1997-01-01

    To investigate the role of the islets of Langerhans in pancreatic carcinogenesis, freshly isolated islets from male Syrian hamsters were transplanted into the right submandibular glands of 50 female hamsters that were or were not pre-treated with streptozotocin. Thyroid gland fragments, cellulose powder, and immortal hamster pancreatic ductal cells were injected into the left submandibular gland of the same hamsters. All recipient hamsters were then treated with the potent pancreatic carcinog...

  12. Labeling of pancreatic islets with iron oxide nanoparticles for in vivo detection with magnetic resonance

    Czech Academy of Sciences Publication Activity Database

    Berková, Z.; Jirák, D.; Zacharovová, K.; Kříž, J.; Lodererová, A.; Girman, P.; Koblas, T.; Dovolilová, E.; Vancová, Marie; Hájek, M.; Saudek, F.

    2008-01-01

    Roč. 85, č. 1 (2008), s. 155-159 ISSN 0041-1337 R&D Projects: GA MŠk 2B06175; GA MŠk LN00A065 Institutional research plan: CEZ:AV0Z60220518 Keywords : pancreatic islet s * islet s transplantation * iron nanoparticles Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 3.816, year: 2008

  13. Fetal rat pancreas transplantation in BB rats: immunohistochemical and functional evaluation

    DEFF Research Database (Denmark)

    Yderstræde, Knud Bonnet; Starklint, Henrik; Steinbrüchel, Daniel Andreas

    1993-01-01

    Spontaneously diabetic BB/Wor rats received either a syngeneic fetal pancreas transplant or adult islets. In the former, 4-8 fetal pancreases were transplanted, and in the latter, 3-5000 islets. Transplantation was performed by transferring a blood clot containing the pancreases or islets...... to the renal subcapsular space. Insulin therapy was undertaken postoperatively, except in one experiment with adult islets. Of the fetal pancreas transplanted BB rats, 52% became normoglycaemic, and 21% remained so throughout an observation period of 10 months. Nephrectomy caused a prompt return of diabetes...... that recurrent diabetes is not inevitable following syngeneic fetal pancreas transplantation to spontaneously diabetic BB rats. Recurrent diabetes was only occasionally associated with mononuclear cell infiltration. Transplanted tissue was well-preserved and vascularized; mega-islets were a constant finding....

  14. Pig Pancreas Anatomy: Implications for Pancreas Procurement, Preservation, and Islet Isolation

    Science.gov (United States)

    Ferrer, Joana; Scott, William E; Weegman, Bradley P; Suszynski, Thomas M; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K

    2009-01-01

    Background Islet transplantation is emerging as a treatment option for selected patients with type 1 diabetes. The limited human islet supply from cadavers and poor islet yield and quality remain substantial impediments to progress in the field. Use of porcine islets holds great promise for large-scale application of islet transplantation. Consistent isolation of porcine islets is dependent on advances in pancreas procurement and preservation, and islet isolation requiring detailed knowledge of the porcine pancreatic anatomy. The primary aim of this study was to describe the vascular and ductal anatomy of the porcine pancreas in order to guide and improve organ preservation and enzyme perfusion. Methods Pancreata were removed by en bloc viscerectomy from 65 female Landrace pigs. Results 15% of organs exhibited inconsistent vascular branching from the celiac trunk. All organs had uniform patterns of branching at the superior mesenteric artery. The superior and inferior mesenteric veins (IMV) merged to become the portal vein in all but one case in which the IMV drained into the splenic vein. 97% of pancreata had three lobes: duodenal (DL), connecting (CL), and splenic (SL); 39% demonstrated ductal communication between the CL and the other two lobes; 50% had ductal communication only between the CL and DL; and 11% presented other types of ductal delineation. Conclusions Accounting for the variations in vascular and ductal anatomy, as detailed in this study, will facilitate development of protocols for preservation, optimal enzyme administration, and pancreas distention and digestion, and ultimately lead to substantial improvements in isolation outcomes. PMID:19077881

  15. Occurance of apoptosis during ischemia in porcine pancreas islet cells.

    Science.gov (United States)

    Stadlbauer, V; Schaffellner, S; Iberer, F; Lackner, C; Liegl, B; Zink, B; Kniepeiss, D; Tscheliessnigg, K H

    2003-03-01

    Pancreas islet transplantation is a potential treatment of diabetes mellitus and porcine organs provide an easily available source of cells. Unfortunately quality and quantity of isolated islets are still not satisfactory. Apoptosis occurs in freshly isolated islets and plays a significant role in early graft loss. We evaluated the influence of four storage solutions on porcine pancreas islets. After warm ischemia of 15-20 minutes 12 organs were stored in 4 cold preservation solutions: Histidine-Tryptophan-Ketoglutarate solution (HTK), Hank's buffered saline solution (HBSS), University of Wisconsin (UW) solution and Ringer-Lactate (R). After cold ischemia for 100 minutes, organs were fixed in 3% formalin. Apoptotic cells were counted on hematocylin-eosin stainings. Most apoptotic cells were found in organs stored in R. Low numbers were found in the other groups. The difference between organs stored in R and organs stored in UW, HTK, or HBSS was highly significant. No significant difference could be found between UW, HTK and HBSS. Cold and warm ischemia of the pancreas seems to induce apoptosis in islet cells. Preservation solutions cause less apoptosis than electrolyte solution. No significant differences could be found among the preservation solutions.

  16. Improved survival of macroencapsulated islets of Langerhans by preimplantation of the immunoisolating device: a morphometric study.

    Science.gov (United States)

    Rafael, E; Wu, G S; Hultenby, K; Tibell, A; Wernerson, A

    2003-01-01

    Encapsulation of cells in a semipermeable membrane may in the future provide an opportunity to treat a variety of endocrine and neurological disorders, without the need for lifelong immunosuppression. The physiological conditions in the device are crucial factors for graft survival. Previously, we have shown that the exchange across the immunoisolating membrane and the microcirculation around the TheraCyte device increase around 3 months after implantation. The aim of this study was to determine whether preimplantation of the TheraCyte device would improve the survival of a later transplanted islet graft. A TheraCyte device was implanted SC on one side of the back of a nondiabetic SD rat. After 3 months, 1500 islets isolated from SD rats were transplanted via the device port. At the same time, another device, loaded with the same number of islets, was implanted on the other side of the back. Both devices were explanted 2 weeks after islet transplantation (i.e., 3.5 months and 0.5 month after device implantation, respectively). Six pairs of devices were evaluated by morphometery. The volume densities of viable islets were 0.22 +/- 0.04 in the preimplanted device vs. 0.06 +/- 0.03 in the nonpreimplanted one (p TheraCyte device seems to improve the survival of an encapsulated islet graft and reduce fibroblast outgrowth in the device.

  17. Guidelines for defining and implementing standard episode of care for hematopoietic stem cell transplantation within the context of clinical trials.

    Science.gov (United States)

    Majhail, Navneet S; Giralt, Sergio; Bonagura, Anthony; Crawford, Stephen; Farnia, Stephanie; Omel, James L; Pasquini, Marcelo; Saber, Wael; LeMaistre, Charles F

    2015-04-01

    The Patient Protection and Affordable Care Act requires that health care insurers cover routine patient costs associated with participating in clinical trials for cancer and other life-threatening diseases. There is a need to better define routine costs within the context of hematopoietic stem cell transplantation (HSCT) clinical trials. This white paper presents guidance on behalf of the American Society for Blood and Marrow Transplantation for defining a standard HSCT episode and delineates components that may be considered as routine patient costs versus research costs. The guidelines will assist investigators, trial sponsors, and transplantation centers in planning for clinical trials that are conducted as a part of the HSCT episode and will inform payers who provide coverage for transplantation. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  18. Non-invasive, in vitro analysis of islet insulin production enabled by an optical porous silicon biosensor.

    Science.gov (United States)

    Chhasatia, Rinku; Sweetman, Martin J; Harding, Frances J; Waibel, Michaela; Kay, Tom; Thomas, Helen; Loudovaris, Thomas; Voelcker, Nicolas H

    2017-05-15

    A label-free porous silicon (pSi) based, optical biosensor, using both an antibody and aptamer bioreceptor motif has been developed for the detection of insulin. Two parallel biosensors were designed and optimised independently, based on each bioreceptor. Both bioreceptors were covalently attached to a thermally hydrosilylated pSi surface though amide coupling, with unreacted surface area rendered stable and low fouling by incorporation of PEG moieties. The insulin detection ability of each biosensor was determined using interferometric reflectance spectroscopy, using a range of different media both with and without serum. Sensing performance was compared in terms of response value, response time and limit of detection (LOD) for each platform. In order to demonstrate the capability of the best performing biosensor to detect insulin from real samples, an in vitro investigation with the aptamer-modified surface was performed. This biosensor was exposed to buffer conditioned by glucose-stimulated human islets, with the result showing a positive response and a high degree of selectivity towards insulin capture. The obtained results correlated well with the ELISA used in the clinic for assaying glucose-stimulated insulin release from donor islets. We anticipate that this type of sensor can be applied as a rapid point-of-use biosensor to assess the quality of donor islets in terms of their insulin production efficiency, prior to transplantation. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Pretargeting vs. direct targeting of human betalox5 islet cells subcutaneously implanted in mice using an anti-human islet cell antibody

    International Nuclear Information System (INIS)

    Liu Guozheng; Dou Shuping; Akalin, Ali; Rusckowski, Mary; Streeter, Philip R.; Shultz, Leonard D.; Greiner, Dale L.

    2012-01-01

    Introduction: We previously demonstrated MORF/cMORF pretargeting of human islets and betalox 5 cells (a human beta cell line) transplanted subcutaneously in mice with the anti-human islet antibody, HPi1. We now compare pretargeting with direct targeting in the beta cell transplant model to evaluate the degree to which target/non-target (T/NT) ratios may be improved by pretargeting. Methods: Specific binding of an anti-human islet antibody HPi1 to the beta cells transplanted subcutaneously in mice was examined against a negative control antibody. We then compared pretargeting by MORF-HPi1 plus 111 In-labeled cMORF to direct targeting by 111 In-labeled HPi1. Results: HPi1 binding to betalox5 human cells in the transplant was shown by immunofluorescence. Normal organ 111 In backgrounds by pretargeting were always lower, although target accumulations were similar. More importantly, the transplant to pancreas and liver ratios was, respectively, 26 and 10 by pretargeting as compared to 9 and 0.6 by direct targeting. Conclusions: Pretargeting greatly improves the T/NT ratios, and based on the estimated endocrine to exocrine ratio within a pancreas, pretargeting may be approaching the sensitivity required for successful imaging of human islets within this organ.

  20. Potential differentiation of islet-like cells from pregnant cow-derived placental stem cells.

    Science.gov (United States)

    Peng, Shao-Yu; Chou, Chien-Wen; Kuo, Yu-Hsuan; Shen, Perng-Chih; Shaw, S W Steven

    2017-06-01

    Type 1 diabetes is an autoimmune disease that destroys islet cells and results in insufficient insulin secretion by pancreatic β-cells. Islet transplantation from donors is an approach used for treating patients with diabetes; however, this therapy is difficult to implement because of the lack of donors. Nevertheless, several stem cells have the potential to differentiate from islet-like cells and enable insulin secretion for treating diabetes in animal models. For example, placenta is considered a waste material and can be harvested noninvasively during delivery without ethical or moral concerns. To date, the differentiation of islet-like cells from cow-derived placental stem cells (CPSCs) has yet to be demonstrated. The investigation of potential differentiation of islet-like cells from CPSCs was conducted by supplementation with nicotinamide, exendin-4, glucose, and poly-d-lysine and was detected through reverse transcription polymerase chain reaction, dithizone staining, and immunocytochemical methods. Our results indicated that CPSCs are established and express mesenchymal stem cell surface antigen markers, such as CD73, CD166, β-integrin, and Oct-4, but not hematopoietic stem cell surface antigen markers, such as CD45. After induction, the CPSCs successfully differentiated into islet-like cells. The CPSC-derived islet-like cells expressed islet cell development-related genes, such as insulin, glucagon, pax-4, Nkx6.1, pax-6, and Fox. Moreover, CPSC-derived islet-like cells can be stained with zinc ions, which are widely distributed in the islet cells and enable insulin secretion. Altogether, islet-like cells have the potential to be differentiated from CPSCs without gene manipulation, and can be used in diabetic animal models in the future for preclinical and drug testing trial investigations. Copyright © 2017. Published by Elsevier B.V.

  1. Transplantation of autologous bone marrow stromal cells (BMSC for CNS disorders – Strategy and tactics for clinical application

    Directory of Open Access Journals (Sweden)

    Satoshi Kuroda

    2010-01-01

    Full Text Available Background – There is increasing evidence that the transplanted bone marrow stromal cells (BMSC significantly promote functional recovery after central nervous system (CNS damage in the animal models of various kinds of CNS disorders, including cerebral infarct, brain contusion and spinal cord injury. However, there are several shortages of information when considering clinical application of BMSC transplantation for patients with neurological disorders. In this paper, therefore, we discuss what we should clarify to establish cell transplantation therapy in clinical situation and describe our recent works for this purpose.Methods and Results – The BMSC have the ability to alter their gene expression profile and phenotype in response to the surrounding circumstances and to protect the neurons by producing some neurotrophic factors. They also promote neurite extension and rebuild the neural circuits in the injured CNS. Using optical imaging and MRI techniques, the transplanted BMSC can non-invasively be tracked in the living animals for at least 8 weeks after transplantation. Functional imaging such as PET scan may have the potential to assess the beneficial effects of BMSC transplantation. The BMSC can be expanded using the animal protein-free culture medium, which would maintain their potential of proliferation, migration, and neural differentiation.Conclusion – It is urgent issues to develop clinical imaging technique to track the transplanted cells in the CNS and evaluate the therapeutic significance of BMSC transplantation in order to establish it as a definite therapeutic strategy in clinical situation in the future

  2. Clinical outcome in children with chronic granulomatous disease managed conservatively or with hematopoietic stem cell transplantation.

    Science.gov (United States)

    Cole, Theresa; Pearce, Mark S; Cant, Andrew J; Cale, Catherine M; Goldblatt, David; Gennery, Andrew R

    2013-11-01

    Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by serious infections and inflammation. It can be managed conservatively with prophylactic antimicrobial agents or curatively with hematopoietic stem cell transplantation (HSCT). In the United Kingdom and Ireland there are cohorts of children managed both conservatively and curatively. This study aimed to compare clinical outcomes (mortality and morbidity) in children managed conservatively and curatively. Children were identified from specialist centers and advertising through special interest groups. Clinical data were collected from medical records regarding infections, inflammatory complications and growth, other admissions, and curative treatment. Comparisons were made for patients not undergoing HSCT and patients after HSCT. Seventy-three living children were identified, 59 (80%) of whom were recruited. Five deceased children were also identified. Clinical information was available for 62 children (4 deceased). Thirty (48%) children had undergone HSCT. Children who did not undergo transplantation had 0.71 episodes of infection/admission/surgery per CGD life year (95% CI, 0.69-0.75 events per year). Post-HSCT children had 0.15 episodes of infection/admission/surgery per transplant year (95% CI, 0.09-0.21 events per year). The mean z score for height and body mass index (BMI) for age was significantly better in post-HSCT children. Survival in the non-HSCT group was 90% at age 15 years. Survival in the post-HSCT group was 90%. Children with CGD not undergoing transplantation have more serious infections, episodes of surgery, and admissions compared with post-HSCT children. Children undergoing transplantation have better height for age. Survival is good at the end of the pediatric age range and also after HSCT. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  3. Enhanced function of immuno-isolated islets in diabetes therapy by co-encapsulation with an anti-inflammatory drug

    OpenAIRE

    Dang, Tram T.; Thai, Anh V.; Cohen, Joshua; Slosberg, Jeremy E.; Siniakowicz, Karolina; Doloff, Joshua C.; Ma, Minglin; Hollister-Lock, Jennifer; Tang, Katherine M.; Gu, Zhen; Cheng, Hao; Weir, Gordon C.; Langer, Robert; Anderson, Daniel Griffith; Tang, Katherine

    2013-01-01

    Immuno-isolation of islets has the potential to enable the replacement of pancreatic function in diabetic patients. However, host response to the encapsulated islets frequently leads to fibrotic overgrowth with subsequent impairment of the transplanted grafts. Here, we identified and incorporated anti-inflammatory agents into islet-containing microcapsules to address this challenge. In vivo subcutaneous screening of 16 small molecule anti-inflammatory drugs was performed to identify promising...

  4. Binding of the fibronectin-mimetic peptide, PR_b, to α5β1 on pig islet cells increases fibronectin production and facilitates internalization of PR_b functionalized liposomes

    Science.gov (United States)

    Atchison, Nicole A.; Fan, Wei; Papas, Klearchos K.; Hering, Bernhard J.; Tsapatsis, Michael; Kokkoli, Efrosini

    2010-01-01

    Islet transplantation is a promising treatment for type 1 diabetes. Recent studies have demonstrated that human islet allografts can restore insulin independence to patients with this disease. As islet isolation and immunotherapeutic techniques improve, the demand for this cell-based therapy will dictate the need for other sources of islets. Pig islets could provide an unlimited supply for xenotransplantation and have shown promise as an alternative to human islet allografts. However, stresses imposed during islet isolation and transplantation decrease islet viability, leading to loss of graft function. In this study, we investigated the ability of a fibronectin-mimetic peptide, PR_b, which specifically binds to the α5β1 integrin, to reestablish lost extracellular matrix (ECM) around isolated pig islets and increase internalization of liposomes. Confocal microscopy and western blotting were used to show the presence of the integrin α5β1 on the pig islets on day 0 (day of isolation), as well as different days of islet culture. Islets cultured in medium supplemented with free PR_b for 48 hours were found to have increased levels of ECM fibronectin secretion compared to islets in normal culture conditions. Using confocal microscopy and flow cytometry we found that PR_b peptide-amphiphile functionalized liposomes delivered to the pig islets internalized into the cells in a PR_b concentration dependent manner, and non-functionalized liposomes showed minimal internalization. These studies proved that the fibronectin-mimetic peptide, PR_b, is an appropriate peptide bullet for applications involving α5β1 expressing pig islet cells. Fibronectin production stimulated through α5β1 PR_b binding may decrease apoptosis and therefore increase islet viability in culture. In addition, PR_b peptide-amphiphile functionalized liposomes may be used for targeted delivery of different agents to pig islet cells. PMID:20704278

  5. Clinical management and outcomes of patients with Hermansky-Pudlak syndrome pulmonary fibrosis evaluated for lung transplantation.

    Science.gov (United States)

    El-Chemaly, Souheil; O'Brien, Kevin J; Nathan, Steven D; Weinhouse, Gerald L; Goldberg, Hilary J; Connors, Jean M; Cui, Ye; Astor, Todd L; Camp, Philip C; Rosas, Ivan O; Lemma, Merte; Speransky, Vladislav; Merideth, Melissa A; Gahl, William A; Gochuico, Bernadette R

    2018-01-01

    Pulmonary fibrosis is a progressive, fatal manifestation of Hermansky-Pudlak syndrome (HPS). Some patients with advanced HPS pulmonary fibrosis undergo lung transplantation despite their disease-associated bleeding tendency; others die while awaiting donor organs. The objective of this study is to determine the clinical management and outcomes of a cohort with advanced HPS pulmonary fibrosis who were evaluated for lung