Successful pregnancy and delivery after simultaneous islet‐kidney transplantation

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.     

Cost and clinical outcome of islet transplantation in Norway 2010‐2015

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.     

Association of cytomegalovirus infections with recurrence of humoral and cellular autoimmunity to islet autoantigens and of type 1 diabetes in a pancreas transplanted patient

Association of type 1 diabetes and cytomegalovirus (CMV) is suspected and CMV infections have also been linked to increased risk of new onset post‐transplantation diabetes. We monitored response to islet autoantigens, pancreatic endocrine function, and CMV infections in one type 1 diabetic patient receiving pancreas allograft. Time course analyses of levels of islet autoantibodies (Abs), IFN‐γ ELISPOT response, analysis of T cell function, levels of C peptide together with CMV pp65 antigenaemia and viraemia and graft biopsy histopathology were performed in comparison with a cohort of diabetic recipients. Evidence of autoimmune activation to GAD and IA2, modification of CD4⁺ CD25hi T cells, loss of pancreatic function, concomitantly with multiple CMV infections and allograft rejection with peri‐insulitis is provided. The parallel between metabolic outcome, initiation and progression of autoreactivity to islet autoantigens and early CMV infections after transplantation, suggests that persistent CMV infections may be relevant to the pathogenesis of type 1 diabetes.     

Pancreas preservation fluid microbial contamination is associated with poor islet isolation outcomes – a multi‐centre cohort study

The microbiological safety of islet preparations is paramount. Preservation medium contamination is frequent, and its impact on islet yield and function remains unclear. Microbiological samples collected during islet isolations from 2006 to 2016 were analyzed and correlated to isolation and allo‐ and autotransplantation outcomes. Microbial contamination of preservation medium was found in 64.4% of processed donor pancreases (291/452). We identified 464 microorganisms including Staphylococcus (253/464, 54.5%), Streptococcus (31/464, 6.7%), and Candida species (25/464, 5.4%). Microbial contamination was associated with longer warm and cold ischemia times and lower numbers of postpurification islet equivalents, purity, transplant rate, and stimulation index (all P < 0.05). Six percent of the preparations accepted for transplantation showed microbial contamination after isolation (12/200); 9 of 12 were Candida species. Six patients were transplanted with a sample with late microbial growth discovered after the infusion. Insulin independence rate was not affected. This risk of transplanting a contaminated islets preparation was reduced by half following the implementation of an additional sampling after 24 h of islet culture. Pancreas preservation fluid microbial contamination is associated with lower transplant rate and poorer in vitro function, but not with changes in graft survival. Culture medium testing 1 day after isolation reduces the risk of incidental transplantation with contaminated islets.     

Live encapsulated porcine islets from a type 1 diabetic patient 9.5 yr after xenotransplantation

BACKGROUND: The long-term viability and function of transplanted encapsulated neonatal porcine islets was examined in a diabetic patient. METHODS AND RESULTS: A 41-yr-old Caucasian male with type 1 diabetes for 18 yr was given an intraperitoneal transplant of alginate-encapsulated porcine islets at the dose of 15,000 islet equivalents (IEQs)/kg bodyweight (total dose 1,305,000 IEQs) via laparoscopy. By 12 weeks following the transplant, his insulin dose was significantly reduced by 30% (P = 0.0001 by multiple regression tests) from 53 units daily prior to transplant. The insulin dose returned to the pre-transplant level at week 49. Improvement in glycaemic control continued as reflected by total glycated haemoglobin of 7.8% at 14 months from a pre-transplant level of 9.3%. Urinary porcine C-peptide peaked at 4 months (9.5 ng/ml) and remained detectable for 11 months (0.6 ng/ml). The patient was followed as part of a long-term microbiologic monitoring programme which subsequently showed no evidence of porcine viral or retroviral infection. At laparoscopy 9.5 yr after transplantation, abundant nodules were seen throughout the peritoneum. Biopsies of the nodules showed opacified capsules containing cell clusters that stained as live cells under fluorescence microscopy. Immunohistology noted sparse insulin and moderate glucagon staining cells. The retrieved capsules produced a small amount of insulin when placed in high glucose concentrations in vitro. An oral glucose tolerance test induced a small rise in serum of immuno-reactive insulin, identified as porcine by reversed phase high pressure liquid chromatography. CONCLUSION: This form of xenotransplantation treatment has the potential for sustained benefit in human type 1 diabetics.     

Islet Transplantation in Type 1 Diabetics Using an Immunosuppressive Protocol Based on the Anti‐LFA‐1 Antibody Efalizumab

The applicability of islet transplantation as treatment for type 1 diabetes is limited by renal and islet toxicities of currently available immunosuppressants. We describe a novel immunosuppressive regimen using the antileukocyte functional antigen‐1 antibody efalizumab which permits long‐term islet allograft survival while reducing the need for corticosteroids and calcineurin inhibitors (CNI). Eight patients with type 1 diabetes and hypoglycemic unawareness received intraportal allogeneic islet transplants. Immunosuppression consisted of antithymocyte globulin induction followed by maintenance with efalizumab and sirolimus or mycophenolate. When efalizumab was withdrawn from the market in mid 2009, all patients were transitioned to regimens consisting of mycophenolate and sirolimus or mycophenolate and tacrolimus. All patients achieved insulin independence and four out of eight patients became independent after single‐islet transplants. Insulin independent patients had no further hypoglycemic events, hemoglobin A1c levels decreased and renal function remained stable. Efalizumab was well tolerated and no serious adverse events were encountered. Although long‐term follow‐up is limited by discontinuation of efalizumab and transition to conventional imunnosuppression (including CNI in four cases), these results demonstrate that insulin independence after islet transplantation can be achieved with a CNI and steroid‐free regimen. Such an approach may minimize renal and islet toxicity and thus further improve long‐term islet allograft survival.     

Dynamic Production of Hypoxia-Inducible Factor-1α in Early Transplanted Islets

More than half of transplanted beta-cells undergo apoptotic cell death triggered by nonimmunological factors within a few days after transplantation. To investigate the dynamic hypoxic responses in early transplanted islets, syngeneic islets were transplanted under the kidney capsule of balb/c mice. Hypoxia-inducible factor-1alpha (HIF-1alpha) was strongly expressed at post-transplant day (POD) 1, increased on POD 3, and gradually diminished on POD 14. Insulin secretion decreased on POD 3 in association with a significant increase of HIF-1alpha-related beta-cell death, which can be suppressed by short-term hyperbaric oxygen therapy. On POD 7, apoptosis was not further activated by continually produced HIF-1alpha. In contrast, improvement of nerve growth factor and duodenal homeobox factor-1 (PDx-1) production resulted in islet graft recovery and remodeling. In addition, significant activation of vascular endothelial growth factor in islet grafts on POD 7 correlated with development of massive newly formed microvessels, whose maturation is advanced on POD 14 with gradual diminution of HIF-1alpha. We conclude that (1) transplanted islets strongly express HIF-1alpha in association with beta-cell death and decreased insulin production until adequate revascularization is established and (2) early suppression of HIF-1alpha results in less beta-cell death thereby minimizing early graft failure.     

Progression of macrovascular diseases is reduced in type 1 diabetic patients after more than 5 years successful combined pancreas-kidney transplantation in comparison to kidney transplantation alone

Recent reports have demonstrated an improved cardiovascular outcome after simultaneous pancreas-kidney transplantation (SPKT) compared with kidney transplantation alone (KTA) in type 1 diabetic patients with end-stage renal disease. The purpose of this study was to determine the impact of SKPT and KTA on the progression of cerebrovascular disease (CVD), coronary heart disease (CHD) and peripheral vascular disease (PVD) 5 and 10 years after transplantation. Only patients with graft survival more than 5 years, were included in this study. In summary, 12 type 1 diabetic patients with SPKT and 10 diabetic subjects with KTA were evaluated. The immunosuppressive therapy was similar in both patient groups. The mean observation period was 124 (72-184) months in the SPKT group and 122 (64-216) months in the group with KTA. To investigate the vascular risk profile we examined mean HbA1c, blood pressure and lipid levels in both patient groups during the first 5 years (period I) and the second 5 years (period II) after transplantation (measurements at least at 3-month intervals). Additionally, we evaluated the prevalence of moderate (stage I-II) and severe (stage III-IV) macrovascular diseases prior as well as 5 and 10 years after transplantation. During period I the mean HbA1c-value was 5.7+/-0.4% in the group with SPKT versus 7.4+/-0.8% in the KTA group, and in period II 5.8+/-0.4% in the SPKT group versus 7.6+/-0.9% (P<0.001) in the patients with KTA. The cholesterol levels were approximately the same in both groups, the triglycerides were lower in the patients with SPKT than in the subjects with KTA with 1.3+/-0.4 vs. 2.2+/-0.9 mmol/l in period I, and 1.4+/-0.5 vs. 2.3+/-0.6 mmol/l in period II (P<0.05). The BP-values were similar in both groups. Five years after transplantation the prevalence of vascular diseases was not significantly different between both groups. During the following 5 years the prevalence of macrovascular diseases increased more in the KTA than in the SKPT group. After a mean observation period of 10 years the SKPT group showed a lower prevalence of vascular diseases (stage I-IV) with 41% CVD, 50% CHD and 50% PAV in comparison to the KTA group with a prevalence of 80% CVD, 90% CHD and 80% PAV), the difference was not statistically significant because of the small patient groups. The frequency of the vascular complications myocardial infarction (16% vs. 50%), stroke (16% vs. 40%) and amputations (16% vs. 30%) was in summary significant lower in the patients with SPKT than in the patients with KTA (P<0.05). In conclusion, while for the first 5 years after transplantation the progression of macroangiopathy in patients with SPKT and KTA was not significantly different, after a mean 10-year observation period the progression of macrovascular diseases was significantly lower in recipients with a functioning SPKT compared to patients with a KTA; this can be explained by a better vascular risk profile after SPKT. The 10-year patient survival was 83% in the SPKT group and 70% in patients with KTA.     

CCL2/MCP‐1 and CXCL12/SDF‐1 blockade by L‐aptamers improve pancreatic islet engraftment and survival in mouse

The blockade of pro‐inflammatory mediators is a successful approach to improve the engraftment after islet transplantation. L‐aptamers are chemically synthesized, nonimmunogenic bio‐stable oligonucleotides that bind and inhibit target molecules conceptually similar to antibodies. We aimed to evaluate if blockade‐aptamer‐based inhibitors of C‐C Motif Chemokine Ligand 2/monocyte chemoattractant protein‐1 (CCL2/MCP‐1) and C‐X‐C Motif Chemokine Ligand 12/stromal cell‐derived factor‐1 (CXCL12/SDF‐1) are able to favor islet survival in mouse models for islet transplantation and for type 1 diabetes. We evaluated the efficacy of the CCL2‐specific mNOX‐E36 and the CXCL12‐specific NOX‐A12 on islet survival in a syngeneic mouse model of intraportal islet transplantation and in a multiple low doses of streptozotocin (MLD‐STZ) diabetes induction model. Moreover, we characterized intrahepatic infiltrated leukocytes by flow cytometry before and 3 days after islet infusion in presence or absence of these inhibitors. The administration for 14 days of mNOX‐E36 and NOX‐A12 significantly improved islet engraftment, either compound alone or in combination. Intrahepatic islet transplantation recruited CD45⁺ leucocytes and more specifically CD45+/CD11b+ mono/macrophages; mNOX‐E36 and NOX‐A12 treatments significantly decreased the recruitment of inflammatory monocytes, CD11b⁺/Ly6C^high/CCR2⁺ and CD11b⁺/Ly6C^high/CXCR4⁺ cells, respectively. Additionally, both L‐aptamers significantly attenuated diabetes progression in the MLD‐STZ model. In conclusion, CCL2/MCP‐1 and CXCL12/SDF‐1 blockade by L‐aptamers is an efficient strategy to improve islet engraftment and survival.     

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

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 <7.0% and freedom of severe hypoglycemia was met by nine of 10 patients after follow‐up after 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 m² 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.     

Loss of end‐differentiated β‐cell phenotype following pancreatic islet transplantation

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.     

Improved Function of Circulating Angiogenic Cells Is Evident in Type 1 Diabetic Islet‐Transplanted Patients

Circulating angiogenic cells (CACs) are vascular‐committed bone marrow‐derived cells that are dysfunctional in type 1 diabetes (T1D). Here we studied whether restoration of normoglycemia following islet transplantation is associated with better CAC function. We carried out a cross‐sectional study of 18 T1D patients, 14 insulin‐independent islet‐transplanted patients (ITA) and 14 healthy controls (C) evaluating in vivo and in vitro CACs viability and function. We found that the percentage of CACs in vivo did not differ among the three groups while the number of CAC colonies obtained from T1D, but not from ITA, was reduced compared to C (C = 7.3 ± 1.9, T1D = 0.9 ± 0.4 and ITA = 4.7 ± 1.9; p < 0.05 T1D vs. all). In vitro CAC migration/differentiation were similar, while in vivo an improved angiogenic ability of ITA compared to T1D was shown (capillary density: C = 93.5 ± 22.1, T1D = 19.2 ± 2.8 and ITA = 44.0 ± 10.5, p < 0.05 T1D vs. all). Increased apoptosis and lesser IL‐8 secretion were evident in CACs obtained from T1D compared to C and ITA. in vitro addition of anti‐hIL‐8 reduced the number of colonies obtained from C. Finally, T1D, but not ITA, had a lower endothelial‐dependent dilatation (EDD) compared with C. These data suggest that CAC function is altered in T1D and may be improved after islet transplantation.     

Combined Islet and Hematopoietic Stem Cell Allotransplantation: A Clinical Pilot Trial to Induce Chimerism and Graft Tolerance

To prevent graft rejection and avoid immunosuppression-related side-effects, we attempted to induce recipient chimerism and graft tolerance in islet transplantation by donor CD34+hematopoietic stem cell (HSC) infusion. Six patients with brittle type 1 Diabetes Mellitus received a single-donor allogeneic islet transplant (8611 ± 2113 IEQ/kg) followed by high doses of donor HSC (4.3 ± 1.9 × 10⁶ HSC/kg), at days 5 and 11 posttransplant, without ablative conditioning. An 'Edmonton-like' immunosuppression was administered, with a single dose of anti-TNFα antibody (Infliximab) added to induction. Immunosuppression was weaned per protocol starting 12 months posttransplant. After transplantation, glucose control significantly improved, with 3 recipients achieving insulin-independence for a short time (24 ± 23 days). No severe hypoglycemia or protocol-related adverse events occurred. Graft function was maximal at 3 months then declined. Two recipients rejected within 6 months due to low immunosuppressive trough levels, whereas 4 completed 1-year follow-up with functioning grafts. Graft failure occurred within 4 months from weaning (478 ± 25 days posttransplant). Peripheral chimerism, as donor leukocytes, was maximal at 1-month (5.92 ± 0.48%), highly reduced at 1-year (0.20 ± 0.08%), and was undetectable at graft failure. CD25+T-lymphocytes significantly decreased at 3 months, but partially recovered thereafter. Combined islet and HSC allotransplantation using an 'Edmonton-like' immunosuppression, without ablative conditioning, did not lead to stable chimerism and graft tolerance.     

BETA‐2 score is an early predictor of graft decline and loss of insulin independence after pancreatic islet allotransplantation

This study aimed to evaluate whether the BETA‐2 score is a reliable early predictor of graft decline and loss of insulin independence after islet allotransplantation. Islet transplant procedures were stratified into 3 groups according to clinical outcome: long‐term insulin independence without islet graft decline (group 1, N = 9), initial insulin independence with subsequent islet graft decline and loss of insulin independence (group 2, N = 13), and no insulin independence (group 3, N = 13). BETA‐2 was calculated on day 75 and multiple times afterwards for up to 145 months posttransplantation. A BETA‐2 score cut‐off of 17.4 on day 75 posttransplantation was discerned between group 1 and groups 2 and 3 (area under the receiver operating characteristic 0.769, P = .005) with a sensitivity and negative predictive value of 100%. Additionally, BETA‐2 ≥ 17.4 at any timepoint during follow‐up reflected islet function required for long‐term insulin independence. While BETA‐2 did not decline below 17.4 for each of the 9 cases from group 1, the score decreased below 17.4 for all transplants from group 2 with subsequent loss of insulin independence. The reduction of BETA‐2 below 17.4 predicted 9 (1.5‐21) months in advance subsequent islet graft decline and loss of insulin independence (P = .03). This finding has important implications for posttransplant monitoring and patient care.