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ObjectivesAge is the strongest risk factor of Giant Cell Arteritis (GCA), implying a possible pathogenetic role of cellular senescence. To address this question, we applied an established senescence specific multi-marker algorithm in tissue artery biopsies (TABs) of GCA patients.MethodsSeventy five positive TABs from GCA patients and 22 negative from patients with Polymyalgia Rheumatica (PMR) were retrospectively retrieved and analyzed. Senescent cells and their histologic origin were identified with specific cellular markers; IL-6 and MMP-9 were investigated as components of the senescent associated secretory phenotype (SASP) by triple co-staining. GCA or PMR artery culture supernatants were applied to primary skin fibroblasts with or without IL-6 blocking agent to explore the induction of IL-6 associated cellular senescence.ResultsSenescent cells were mainly present in GCA arteries at higher proportion compared to PMR (9.50% vs 2.66% respectively, pConclusionsSenescent cells with inflammatory phenotype are present in GCA arteries and are associated with the tissue inflammatory bulk. These findings might suggest a potential implication in disease pathogenesis by perpetuating inflammation and affecting vascular remodeling via IL-6 dependent mechanisms.

We aimed at explaining the mechanism of therapeutic effect of Umbilical Cord Mesenchymal Stem Cells (UC-MSC) in subjects with COVID-19 Acute Respiratory Distress Syndrome (ARDS). Patients with COVID-19 ARDS present with a hyperinflammatory response characterized by high levels of circulating pro-inflammatory mediators, including tumor necrosis factor α and β (TNFα and TNFβ). Inflammatory functions of these TNFs can be inhibited by soluble TNF Receptor 2 (sTNFR2). In patients with COVID-19 ARDS, UC-MSC appear to impart a robust anti-inflammatory effect, and treatment is associated with remarkable clinical improvements. We investigated the levels of TNFα, TNFβ and sTNFR2 in blood plasma samples collected from subjects with COVID-19 ARDS enrolled in our trial of UC-MSC treatment.We analyzed plasma samples from subjects with COVID-19 ARDS (n=24) enrolled in a Phase 1/2a randomized controlled trial of UC-MSC treatment. Plasma samples were obtained at Day 0 (baseline, before UC-MSC or control infusion), and Day 6 post infusion. Plasma concentrations of sTNFR2, TNFα, and TNFβ were evaluated using a quantitative multiplex protein array.Our data indicate that at Day 6 after infusion, UC-MSC recipients develop significantly increased levels of plasma sTNFR2 and significantly decreased levels of TNFα and TNFβ, compared to controls.These observations suggest that sTNFR2 plays a mechanistic role in mediating UC-MSC effect on TNFα and TNFβ plasma levels, determining a decrease in inflammation in COVID-19 ARDS.

BACKGROUND: Wolfram Syndrome 1 (WS1) has been characterized on the basis of mutation in the WFS1 gene encoding a calcium storage wolframin endoplasmatic reticulum transmembrane glycoprotein. PATIENTS AND METHODS: We observed a WS 10-years old female subject, with Type 1 diabetes-mellitus (DM), that had compound heterozygous WSF1 mutations but without other symptoms generally observed in WS subjects, such as optic atrophy or neurodegeneration. RESULTS: Decreased copper, ceruloplasmin, and transferrin levels, pointing to a copper deficiency, were associated with a new c.18703A>G mutation in the ATP7B gene, while lower calcium levels were associated with WSF1 mutations. An omega-3 fatty acids therapy was administrated to the subject in the attempt to ameliorate diabetes symptoms, restored copper deficiency, and normal calcium levels. CONCLUSIONS: This specific case report provides new insights into the potential interplay of ATP7B mutation in shaping a milder WS clinical picture.

Our goal was to assess the efficacy of encapsulated allogeneic islets transplanted in diabetic NOD mice and streptozotocin (STZ)-diabetic nonhuman primates (NHPs).Murine or NHP islets were microencapsulated and transplanted in non-immunosuppressed mice or NHPs given clinically-acceptable immunosuppressive regimens, respectively. Two NHPs were treated with autologous mesenchymal stem cells (MSCs) and peri-transplant oxygen therapy. Different transplant sites (intraperitoneal [i.p.], omental pouch, omental surface, and bursa omentalis) were tested in separate NHPs. Graft function was monitored by exogenous insulin requirements, fasting blood glucose levels, glucose tolerance tests, percent hemoglobin A1c (% HbA1c), and C-peptide levels. In vitro assessment of grafts included histology, immunohistochemistry, and viability staining; host immune responses were characterized by flow cytometry and cytokine/chemokine multiplex ELISAS.Microencapsulated islet allografts functioned long-term i.p. in diabetic NOD mice without immunosuppression, but for a relatively short time in immunosuppressed NHPs. In the NHPs, encapsulated allo-islets initially reduced hyperglycemia, decreased exogenous insulin requirements, elevated C-peptide levels, and lowered % HbA1c in plasma, but graft function diminished with time, regardless of transplant site. At necropsy, microcapsules were intact and non-fibrotic, but many islets exhibited volume loss, central necrosis and endogenous markers of hypoxia. Animals receiving supplemental oxygen and autologous MSCs showed improved graft function for a longer post-transplant period. In diabetic NHPs and mice, cell-free microcapsules did not elicit a fibrotic response.The evidence suggested that hypoxia was a major factor for damage to encapsulated islets in vivo. To achieve long-term function, new approaches must be developed to increase the oxygen supply to microencapsulated islets and/or identify donor insulin-secreting cells which can tolerate hypoxia.

The clinical benefit of islet allo- and autotransplantation is limited by a massive loss of implanted cells immediately postimplantation. Episodes of more subtle beta cell loss occur during the natural history of type 1 diabetes and at later time points posttransplantation. Our understanding of the disease and the development of innovative therapies to preserve or restore a sufficient beta-cell mass would benefit from noninvasive measures to detect and quantify episodes of beta-cell destruction. This can be assessed indirectly by monitoring changes in functional beta-cell mass, most precisely and accurately by hyperglycemic clamp test. Non-secreted beta cell-selective proteins, unmethylated gene regions, and microRNAs (miRs) have been validated as circulating markers of ongoing beta-cell damage. In the context of islet transplantation, 65 kDa-glutamate decarboxylase and miR-375 have been most closely associated with beta-cell loss and subsequent graft function.

Beta cell replacement has the potential to restore euglycemia in patients with insulin dependent diabetes. While great progress has been made in establishing allogeneic islet transplantation from deceased donors as the standard of care for those with the most labile diabetes, it is also clear that the deceased donor organ supply cannot possibly treat all those who could benefit from restoration of a normal beta cell mass, especially if immunosuppression were not required. Against this background, the International Pancreas and Islet Transplant Association (IPITA) in collaboration with the Harvard Stem Cell Institute (HSCI), the Juvenile Diabetes Research Foundation (JDRF), and the Helmsley Foundation held a 2-day Key Opinion Leaders Meeting in Boston in 2016 to bring together experts in generating and transplanting beta cells derived from stem cells. The following summary highlights current technology, recent significant breakthroughs, unmet needs and roadblocks to stem-cell-derived beta cell therapies, with the aim of spurring future preclinical collaborative investigations and progress toward the clinical application of stem cell-derived beta cells.

In this study, we evaluated the metabolomic profiling of cryopreserved Lipogems® tissue products and the initial lipoaspirates before microfracturing, to determine altered metabolites that could result from the non-enzymatic processing or the cryopreservation method.Human Lipoaspirate samples (n=10) were divided in two aliquots, of which one was non-processed and the other was processed by Lipogems® device. Non-processed lipoaspirates and Lipogems® processed tissues were stored at -80°C fresh frozen (N=3 per group) or in the presence of 0.5 M dimethyl sulfoxide (DMSO) (N=7 per group). A global non-targeted metabolic profile on these samples was performed.Differences were observed in carbohydrate and nucleotide metabolism. These alterations translated in long chain and polyunsaturated fatty acid levels and amino acid metabolites showed divergent trends. When Lipogems® and Lipoaspirate tissue products were cryopreserved with DMSO, amino acids tended to increase in Lipogems® product. However, in the absence of DMSO aminoacids and their catabolites, tended to decrease in Lipogems® fat tissue product.Microfractured human adipose tissue has been shown to provide a more effective source of adult stromal cells compared to the initial lipoaspirated tissue material. These could be, according to our findings, due to the changes in the metabolic profile of lipoaspirate tissues products.

Two cases of Type 1 Diabetes (T1D) in pediatric subjects treated with supplementation with high dose vitamin D and omega 3 are reported. A similar pattern of remission of the disease was observed, resulting in restoration and subsequent persistence of optimal metabolic control, one and two years after T1D onset. Minimal basal insulin administration (0.1 IU/kg/die) in a single evening injection was required. The immunomodulatory and anti-inflammatory properties of the supplements were likely contributing to the observed effect. Similarities in genotyping and autoantibody patterns in these two cases could be of assistance to identify which subjects with T1D could benefit from this supplemental therapy. High dose vitamin D and omega 3 could be of assistance in childhood T1D therapy, to prolong preservation of endogenous insulin secretion in the absence of side effects. We do not know how long the state of remission can last, but these initial results are promising and represented a significant benefit for the two pediatric subjects treated. Larger controlled studies will determine the long-term effect of this proposed supplementation and its possible cost-benefits, including reduction of hypoglycemic episodes and complications.

Early diagnosis of diabetes mellitus can significantly improve therapeutic strategies and overall health span. Identifying biomarkers as a tool for determining the risk of developing diabetes as well as a monitoring strategy for progression of the disease state would be useful in predicting potential complications while simultaneously improving our ability to prevent and treat diabetes. Extracellular vesicles (EV) have recently emerged as prominent mediators of intercellular communication and as a potential source for the discovery of novel biomarkers. A deeper understanding of the cargo molecules present in EVs obtained from type 1 diabetes mellitus (T1D) patients may aid in the identification of novel diagnostic and prognostic biomarkers, and can potentially lead to the discovery of new therapeutic targets.

Liver transplantation (LT) is a life-saving treatment for liver cirrhosis patients with hepatocellular carcinoma (HCC). However, 10%-20% HCC recurrence rate after LT is due to the immunosuppression inducing tumor growth. We recently reported a novel immunotherapy with donor liver natural killer (NK) cells to prevent HCC and hepatitis C virus (HCV) recurrence after LT. In this cell processing procedure, Muromonab-CD3 (Orthoclone OKT3, an anti-CD3 antibody) was added to the culture medium to deplete CD3(+) T cells to prevent graft-versus-host disease. However, the manufacture of OKT3 was discontinued in 2010, when other treatments with similar efficacy and fewer side effects became available. In this study, we examined alternative reagents for T-cell depletion-MACS GMP CD3 pure (GMP CD3), antithymocyte globulin, and alemtuzumab-for NK cell immunotherapy in the allogeneic setting. We observed that GMP CD3 showed exactly the same effects on liver mononuclear cells as OKT3, including activation of NK cells and depletion of T cells. Interestingly, binding of T-cell depletion antibodies to NK cells led to an anti-HCV effect via interferon-γ production. These results with the use of in vitro culture systems suggested that antibodies which produce T-cell depletion affected NK cell function.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:58:03Z No. of bitstreams: 1 S0102-86502003000200003.pdf: 157430 bytes, checksum: 524a5aec9f702a32d0de607f2c12a61f (MD5) Made available in DSpace on 2013-08-22T18:58:03Z (GMT). No. of bitstreams: 1 S0102-86502003000200003.pdf: 157430 bytes, checksum: 524a5aec9f702a32d0de607f2c12a61f (MD5) Previous issue date: 2003-03-01 Made available in DSpace on 2013-09-30T19:53:27Z (GMT). No. of bitstreams: 2 S0102-86502003000200003.pdf: 157430 bytes, checksum: 524a5aec9f702a32d0de607f2c12a61f (MD5) S0102-86502003000200003.pdf.txt: 19803 bytes, checksum: 8c0a28327eac25021e0732501b420d81 (MD5) Previous issue date: 2003-03-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:32:24Z No. of bitstreams: 2 S0102-86502003000200003.pdf: 157430 bytes, checksum: 524a5aec9f702a32d0de607f2c12a61f (MD5) S0102-86502003000200003.pdf.txt: 19803 bytes, checksum: 8c0a28327eac25021e0732501b420d81 (MD5) Made available in DSpace on 2014-05-20T13:32:24Z (GMT). No. of bitstreams: 2 S0102-86502003000200003.pdf: 157430 bytes, checksum: 524a5aec9f702a32d0de607f2c12a61f (MD5) S0102-86502003000200003.pdf.txt: 19803 bytes, checksum: 8c0a28327eac25021e0732501b420d81 (MD5) Previous issue date: 2003-03-01 Baixas doses de irradiação associadas à infusão de células da medula óssea não previnem a ocorrência da reação do enxerto versus hospedeiro após o transplante intestinal. OBJETIVO: Neste estudo foi avaliado a potencial vantagem em estender o regime imunossupressor associado a infusão de células de medula óssea do doador depletadas de células T na prevenção da reação do enxerto versus hospedeiro após o transplante intestinal. MÉTODOS: Transplante heterotópico de intestino delgado foi realizado em ratos Lewis como receptores e da como doadores, distribuídos em cinco grupos de acordo com a duração da imunossupressão, irradiação e do uso de medula óssea normal ou depletada: G1 (n=6), sem irradiação e G2 (n=9), G3 (n=4), G4 (n=5) e G5 (n=6) foram irradiados com 250 rd. Grupos1, 2, 4 e G3 e 5 foram infundidos com 100 x 10(6) células da medula normal e depletada respectivamente. Animais no G1,2,3 foram imunossuprimidos com 1mg/kg/FK506/ IM por cinco dias e G4 e cinco por 15 dias. Anticorpos monoclonais contra células CD3 e colunas magnéticas foram utilizadas para a depleção da medula óssea. Os animais foram examinados para a presença de rejeição, reação do enxerto versus hospedeiro, chimerismo e biópsias intestinais e da pele. RESULTADOS: Rejeição mínima foi observada em todos os grupos; entretanto, a reação do enxerto versus hospedeiro somente nos animais irradiados. Extensão da imunossupressão alterou a gravidade da reação nos animais dos G4 e 5. Rejeição foi a causa mortis no G1 e a reação do enxerto versus hospedeiro nos Grupos 2,3,4 e 5, não controlada com a infusão de medula óssea depletada. O chimerismo total e de células T do doador foi estatisticamente maior nos grupos irradiados em comparação ao G1. CONCLUSÃO: A extensão do regime de imunossupressão associado a baixas doses de irradiação diminui a gravidade da reação do enxerto versus hospedeiro, não abolida pelo uso de medula óssea depletada. Low cytoreductive regimen of irradiation associated to unmodified bone marrow infusion (UBM) does not prevent the occurrence of graft versus host disease (GVHD) after transplant. PURPOSE: In this study we evaluated the potential advantages of a long-term immunossupression and T-cell depleted bone marrow infusion (TCDBMI) in preventing the occurrence of GVHD after small bowel transplantation (SBTx). METHODS: Heterotopic SBTX was performed with Lewis rats as recipients and da as donors and distributed into 5 groups according to the irradiation, duration of immunossupression and the use of UBM or TCDBMI: G1 (n=6), without irradiation and G2 (n=9), G3 (n=4), G4 (n=5) and G5 (n=6) was given 250 rd of irradiation. Groups 1,2,4 and G3 and 5 were infused with 100 x 10(6) UBM and TCDBM respectively. Animals in G1, 2, 3 were immunossupressed with 1mg/ FK506/Kg/IM for 5 days and G4 and G5 for 15 days. Anti CD3 monoclonal antibodies and immunomagnetic beads were used for T-cell depletion.Animals were examined for rejection, GVHD, chimerism characterization and ileal and skin biopsies. RESULTS: Minimal to mild rejection was observed in all groups; however, GVHD were present only in irradiated groups. Long-term immunossupression changed the severity of GVHD in G4 and G5. Rejection was the cause of death in G1 while GVHD in G2, 3, 4 and 5, not avoided by the use of TCDBMI. Total chimerism and T-cell chimerism was statistically higher in irradiated groups when compared to G1. CONCLUSION: Extended immunossupression associated to low dose of irradiation decrease the severity of GVHD, not avoided by the use of TCDBMI. UNESP Department of Surgery Division of Liver and GI Transplantation University of Miami Transplant Division UNESP Department of Pathology Division of Immunopathology UNESP Department of Surgery Division of Kidney and Pancreas Transplantation Diabetes Research Institute and Cell Transplantation Center Botucatu Faculty of Medicine Department of Surgery UNESP Department of Surgery Division of Liver and GI Transplantation UNESP Department of Pathology Division of Immunopathology UNESP Department of Surgery Division of Kidney and Pancreas Transplantation

Obesity, metabolic syndrome and diabetes represent multi-factorial conditions resulting from improper balances of hormones and gene expression. In addition, these conditions have a strong inflammatory component that can potentially be impacted by the diet. The purpose of this review is to discuss the molecular targets that can be addressed by anti-inflammatory nutrition. These molecular targets range from reduction of pro-inflammatory eicosanoids that can alter hormonal signaling cascades to the modulation of the innate immune system, via toll-like receptors and gene transcription factors. Working knowledge of the impact of nutrients, especially dietary fatty acids and polyphenols, on these various molecular targets makes it possible to develop a general outline of an anti-inflammatory diet that offers a unique, non-pharmacological approach for treating obesity, metabolic syndrome and diabetes.

As part of our ongoing effort to develop biohybrid devices for pancreatic islet transplantation, we are interested in establishing the feasibility of a localized immune-suppressive approach to avoid or minimize the undesirable side effects of existing systemic treatments. Since biohybrid devices can also incorporate biocompatible scaffold constructs to provide a support environment for the transplanted cells that enhances their engraftment and long-term function, we are particularly interested in an approach that would use the same three-dimensional construct, or part of the same construct, to also provide sustained release of therapeutic agents to modulate the inflammatory and immune responses locally. Within this framework, here, we report preliminary results obtained during the investigation of the suitability of organosilicone constructs for providing sustained localized drug release using small, matrix-type polydimethylsiloxane (PDMS) disks and dexamethasone as a model hydrophobic drug. Following a short burst, long-term steady sustained release was observed under in vitro conditions at levels of 0.1-0.5 microg/day/disk with a profile in excellent agreement with that predicted by the Higuchi equation. To verify that therapeutic levels can be achieved, suppression of LPS-induced activation has been shown in THP-1 cells with disks that have been pre-soaked for up to 28 days. These preliminary results prove the feasibility of this approach where an integral part of the biomaterial construct used to enhance cell engraftment and long-term function also serves to provide sustained local drug release.

This report provides our initial experience on islet isolation and intrahepatic allotransplantation in 20 patients. In Group 1, 10 patients underwent combined liver-islet allotransplantation following upper-abdominal exenteration for cancer. One patient underwent pancreatic islet allograft after near total pancreatectomy for chronic pancreatitis. In Group 2, 3 Type I diabetic patients received a combined liver-islet allograft for cirrhosis and diabetes. In Group 3, 7 Type I diabetic patients received 8 combined cadaveric kidney-islet grafts (one retransplant) for end stage renal disease. The islets were separated by a modification of the automated method for human islet isolation and the preparations were infused into the portal vein. Immunosuppression was with FK-506 (Group 1) plus steroids (Groups 2 and 3). Six patients in Group 1 did not require insulin treatment for 5 to >16 mo. In Groups 2 and 3 none of the patients became insulin-independent, although ongoing C-peptide secretion, decreased insulin requirement and stabilization of diabetes were observed. Our results indicate that islet transplantation is most effective in pancreatectomy induced diabetes. However, rejection is still a major factor limiting the clinical application of islet transplantation in patients with Type I diabetes mellitus. Other factors such as steroid treatment may contribute to deteriorate islet engraftment and/or function.

The outcome of human islet isolation procedures can be significantly effected by the technique used for pancreas procurement. In fact, the final step of islet purification using discontinuous density gradients requires a significant difference between the density of the islets and the density of the non-endocrine component of the gland. Therefore, any procedure during multi-organ procurement that will result in edema or degranulation of the acinar tissue will result in failure of the islet purification step. In this report a technique for combined harvesting of liver and pancreas is presented. The use of this procedure can be of assistance to avoid damage to the pancreas that could result in a compromised islet purification for improper handling of the gland even before it arrives to the isolation facility.

Quantification of islet mass is a crucial criterion for defining the quality of the islet product ensuring a potent islet transplant when used as a therapeutic intervention for select patients with type I diabetes.This multi-center study involved all eight member institutions of the National Institutes of Health-supported Islet Cell Resources Consortium. The study was designed to validate the standard counting procedure for quantifying isolated, dithizone-stained human islets as a reliable methodology by ascertaining the accuracy, repeatability (intra-observer variability), and intermediate precision (inter-observer variability). The secondary aim of the study was to evaluate a new software-assisted digital image analysis method as a supplement for islet quantification.The study demonstrated the accuracy, repeatability and intermediate precision of the standard counting procedure for isolated human islets. This study also demonstrated that software-assisted digital image analysis as a supplemental method for islet quantification was more accurate and consistent than the standard manual counting method.Standard counting procedures for enumerating isolated stained human islets is a valid methodology, but computer-assisted digital image analysis assessment of islet mass has the added benefit of providing a permanent record of the isolated islet product being evaluated that improves quality assurance operations of current good manufacturing practice.

Purification is one of the most important steps in human islet isolation. Although Ficoll-based density gradients are widely used, OptiPrep-based density gradients are used in few centers. Cytokine/chemokine production from human islet preparations varies widely. Some cytokines/chemokines have been reported to have adverse effects on human islet preparations. Control of cytokine/chemokine production may be a key to improve islet quality and quantity, leading to better transplantation outcomes. The aim of the present study was to investigate the effects on islet preparations of purification methods using various density gradients on viability, cellular composition, and proinflammatory cytokine/chemokine production. After the digestion phase, the extracts were divided into 2 groups for purification using a semiautomated cell processor with Ficoll-based or OptiPrep-based density gradients. Islet preparations cultured for 2 days were assessed regarding islet cell viability (fluorescein diacetate/propidium iodide [FDA/PI]), fractional beta-cell viability by FACS, and beta-cell content using iCys. Cytokine/chemokine production from islet preparations was also measured by Bio-plex. After purification, the purity, islet equivalents (IEQ), and islet recovery rates were comparable between the 2 groups. Although FDA/PI and fractional beta-cell viability showed no significant difference, survival of beta cells during culture was significantly higher in the OptiPrep compared with the Ficoll-based density gradient group. There were significantly lower tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon (IFN)-gamma, IL-6, and MIP-1beta productions from the OptiPrep-based density gradient group. OptiPrep-based density gradients reduced cytokine/chemokine production by islet preparations. In addition, OptiPrep-based density gradient purification significantly reduced the loss of beta-cell mass during pretransplantation culture.

Laser scanning cytometry (iCys; CompuCyte, Cambridge, Mass) has recently been developed to use fluorescence-based quantitative measurements on tissue sections or other cellular preparations at a single-cell level. The purpose of this study was to develop objective, quantitative immunoprofiling of regulatory T cells (T regs) on formalin-fixed/paraffin-embedded (FFPE) biopsy samples from transplanted allografts using iCys. We sought to evaluate the usefulness of iCys to analyzes the population of CD4 (+) Foxp3 (+) T regs among CD4 (+) T-cell and the entire T-cell (the total of CD4 [+] and CD8 [+] populations in human intestinal allograft biopsy samples. Primary antibodies (Foxp3 and CD4) which had been labeled using Alexa Fluoro 488 (Foxp3 Alexa488) and 647 (CD4 Alexa647) with polymer horseradish peroxidase and catalyzed signal amplification were incubated on 1 section. On the other section, CD8 and CD4 were labeled using Alexa488 and Alexa647 using the same protocol. Data acquisition was performed using iCys. The signal intensities of Alexa488 and Alexa647 were sufficient to analyze by iCys. Distribution of the integrals of Alexa488 and Alexa647 to visualize each cell population enabled calculation of the population of T reg among CD4 (+) T cells, CD4 (+) T cells among total T cells, and T reg among entire T cells. iCys and signal amplified immunofluorescent staining allowed objective uantitative immunoprofiling of in situ T reg populations, with precise quantitative analysis at a single-cell level on FFPE sections. This objective method may be applied on biopsy samples from various transplanted organs.

Achieving stable metabolic control in patients with type 1 diabetes mellitus (T1DM) is highly desirable and may contribute to delaying and/or preventing the development of secondary complications. Transplantation of pancreatic islets represents a viable option for the treatment of patients with unstable T1DM with frequent severe hypoglycemia and hypoglycemia unawareness. The benefits of the transplant include improvement of glycemic control, prevention of severe hypoglycemia and amelioration of quality of life. The success of future clinical trials will depend on the implementation of an integrated therapeutic approach combining strategies to maximize islet availability and engraftment with those aiming at safely modulating the recipients' immunity to afford long-term function. The steady progress of recent years in islet cell processing and patient management after transplantation justify great optimism for the years to come.