Pancreas transplantation: review.

Pancreas transplant (PTx) is the only treatment that establishes normal glucose levels for patients diagnosed with diabetes types 1 and 2. The paper aims to review and analyze graft survival, patient survival, and the impact on diabetic complications. We describe that the graft survival was 82-98% at 1 year, 90% at 5 years, and 75-54% at 10 years for simultaneous pancreas-kidney recipient; 71% pancreas after kidney (PAK), and 62% PTx alone at 1 year. Patient survival: At 1 year for recipients was 96.9% simultaneous pancreas-kidney transplantation (SPK); for PAK transplantation recipients, 96.3%; and for PTx alone recipients, 98.3%. In general, the pancreas transplantation improves and reverses diabetic complications. Finally, the pancreatic transplant is a morbid procedure and emerges as a significant alternative in diabetes management, directly competing with conventional insulin therapies. Results so far suggest that the most effective transplant model is the SPK. While more patients could benefit from this procedure, surgical complications and the need for immunosuppression pose significant challenges.

El trasplante de páncreas es el único tratamiento que estabiliza los niveles normales de glucosa en los pacientes diagnosticados con diabetes tipo 1 o tipo 2. En esta revisión se analizan la supervivencia del injerto, la supervivencia del paciente y el impacto en las complicaciones diabéticas. Se describe la supervivencia del injerto: 82-98% al año para los receptores de trasplante simultáneo de páncreas y riñón, 71% para trasplante páncreas después de riñón y 62% para trasplante de páncreas solitario al año. Supervivencia de los pacientes a 1 año: 96.9% para los receptores de trasplante simultáneo de páncreas y riñón, 96.3% para los receptores de trasplante de páncreas después de riñón y 98.3% para los receptores de páncreas solitario. En general, el trasplante de páncreas mejora y revierte las complicaciones diabéticas. Finalmente, el trasplante de páncreas, un procedimiento mórbido, surge como una alternativa significativa en el manejo de la diabetes, compitiendo directamente con las terapias convencionales de insulina. Hasta ahora, los resultados indican que el modelo de trasplante más efectivo es el simultáneo de páncreas y riñón. Aunque más pacientes podrían beneficiarse de este procedimiento, las complicaciones quirúrgicas y la necesidad de inmunosupresión plantean desafíos significativos.

Assessing the influence of graft loss on 4-year patient survival after simultaneous pancreas-kidney transplantation: Kaplan-Meier versus Competing Risk Analysis model.

BACKGROUND: Graft loss increases the risk of patient death after simultaneous pancreas-kidney (SPK) transplantation. The relative risk of each graft failure is complex due to the influence of several competing events. METHODS: This retrospective, single-center study compared 4-year patient survival according to the graft status using Kaplan-Meier (KM) and Competing Risk Analysis (CRA). Patient survival was also assessed according to five eras (Era 1: 2001-2003; Era 2: 2004-2006; Era 3: 2007-2009; Era 4: 2010-2012; Era 5: 2012-2015). RESULTS: Between 2000 and 2015, 432 SPK transplants were performed. Using KM, patient survival was 86.5% for patients without graft loss (n = 333), 93.4% for patients with pancreas graft loss (n = 46), 43.7% for patients with kidney graft loss (n = 16), and 25.4% for patients with pancreas and kidney graft loss (n = 37). Patient survival was underestimated using KM versus CRA methods in patients with pancreas and kidney graft losses (25.4% vs. 36.2%), respectively. Induction with lymphocyte depleting antibodies was associated with 81% reduced risk (HR.19, 95% CI.38-.98, p = .0048), while delayed kidney function (HR 2.94, 95% CI 1.09-7.95, p = .033) and surgical complications (HR 2.94, 95% CI 1.22-7.08, p = .016) were associated with higher risk of death. Four-year patient survival increased from Era 1 to Era 5 (79% vs. 87.9%, p = .047). CONCLUSION: In this cohort of patients, kidney graft loss, with or without pancreas graft loss, was associated with higher mortality after SPK transplantation. Compared to CRA, the KM model underestimated survival only among patients with pancreas and kidney graft losses. Patient survival increased over time.

Pancreatic islet transplantation in type 1 diabetes: 20-year experience from a single-centre cohort in Canada.

BACKGROUND: Islet transplantation offers an effective treatment for selected people with type 1 diabetes and intractable hypoglycaemia. Long-term experience, however, remains limited. We report outcomes from a single-centre cohort up to 20 years after islet transplantation. METHODS: This cohort study included patients older than 18 years with type 1 diabetes undergoing allogeneic islet transplantation between March 11, 1999, and Oct 1, 2019, at the University of Alberta Hospital (Edmonton, AB, Canada). Patients who underwent islet-after-kidney transplantation and islet transplantation alone or islet transplantation before whole-pancreas transplantation (follow-up was censored at the time of whole-pancreas transplantation) were included. Patient survival, graft survival (fasting plasma C-peptide >0·1 nmol/L), insulin independence, glycaemic control, and adverse events are reported. To identify factors associated with prolonged graft survival, recipients with sustained graft survival (≥90% of patient follow-up duration) were compared with those who had non-sustained graft survival (<90% of follow-up duration). Multivariate binary logistic regression analyses were done to determine predictors of sustained graft survival. FINDINGS: Between March 11, 1999, and Oct 1, 2019, 255 patients underwent islet transplantation and were included in the analyses (149 [58%] were female and 218 [85%] were White). Over a median follow-up of 7·4 years (IQR 4·4-12·2), 230 (90%) patients survived. Median graft survival was 5·9 years (IQR 3·0-9·5), and graft failure occurred in 91 (36%) patients. 178 (70%) recipients had sustained graft survival, and 77 (30%) had non-sustained graft survival. At baseline, compared with patients with non-sustained graft survival, those with sustained graft survival had longer median type 1 diabetes duration (33·5 years [IQR 24·3-41·7] vs 26·2 years [17·0-35·5]; p=0·0003), median older age (49·4 years [43·5-56·1] vs 44·2 years [35·4-54·2]; p=0·0011), and lower median insulin requirements (0·53 units/kg per day [0·45-0·67] vs 0·59 units/kg per day [0·48-0·70]; p=0·032), but median HbA1c concentrations were similar (8·2% [7·5-9·0] vs 8·5% [7·8-9·2]; p=0·23). 201 (79%) recipients had insulin independence, with a Kaplan-Meier estimate of 61% (95% CI 54-67) at 1 year, 32% (25-39) at 5 years, 20% (14-27) at 10 years, 11% (6-18) at 15 years, and 8% (2-17) at 20 years. Patients with sustained graft survival had significantly higher rates of insulin independence (160 [90%] of 178 vs 41 [53%] of 77; p<0·0001) and sustained improvements in glycaemic control mixed-main-effects model group effect, p<0·0001) compared with those with non-sustained graft survival. Multivariate analyses identified the combined use of anakinra plus etanercept (adjusted odds ratio 7·5 [95% CI 2·7-21·0], p<0·0001) and the BETA-2 score of 15 or higher (4·1 [1·5-11·4], p=0·0066) as factors associated with sustained graft survival. In recipients with sustained graft survival, the incidence of procedural complications was lower (23 [5%] of 443 infusions vs 17 [10%] of 167 infusions; p=0·027), whereas the incidence of cancer was higher (29 of [16%] of 178 vs four [5%] of 77; p=0·015) than in those with non-sustained graft survival; most were skin cancers (22 [67%] of 33). End-stage renal disease and severe infections were similar between groups. INTERPRETATION: We present the largest single-centre cohort study of long-term outcomes following islet transplantation. Although some limitations with our study remain, such as the retrospective component, a relatively small sample size, and the absence of non-transplant controls, we found that the combined use of anakinra plus etanercept and the BETA-2 score were associated with improved outcomes, and therefore these factors could inform clinical practice. FUNDING: None.

Pancreatic transplantation with duodenoduodenostomy drainage: technique, normal radiological appearance and complications.

Pancreas transplantation is considered the curative treatment for severe type 1 diabetes mellitus in selected cases. Since the first procedure in 1966, surgical techniques have been improved. The current trend among most medical centers, as well as at our Institution, is enteric drainage and systemic venous or portal anastomosis. The aim of this pictorial essay is to describe the main imaging features of pancreatic transplantation with duodenoduodenostomy drainage.

The quality of life in type I diabetic patients with end-stage kidney disease before and after simultaneous pancreas-kidney transplantation: a single-center prospective study.

Simultaneous pancreas-kidney transplantation (SPKT) aimed at increasing the life expectancy for diabetic patients with end-stage kidney disease (ESKD). However, the risks of surgery complications and immunosuppression therapy make it unclear if the SPKT positively impacts patient's quality of life (QoL). Using the Kidney Disease Quality of Life-Short-Form Health Survey (KDQOL-SF36) and Problems Areas in Diabetes (PAID) measurement tools, we compared the QoL of 57 patients on the pretransplant waiting list with that of 103 patients who had undergone SPKT. Posttransplantation patients were assessed within different time intervals (<1, 1-3, and >3 years). Mean KDQOL-SF36 scores were better among posttransplantation patients in the SF36 and KDQOL domains. It was also observed patients' stress reduction in PAID mean score (P = 0.011) after SPKT. We concluded that patients receiving SPKT had a better perception of QoL than did patients on the waiting list, and this positive perception remained almost entirely comparable over the three different intervals of the posttransplantation time. These positive results showed better outcomes when excluding patients that lost pancreas graft function. Further research is needed to compare diabetic patients with kidney transplant alone using specific measurement tools to evaluate patient's QoL.

The effect of metabolic surgery on type 1 diabetes: meta-analysis.

OBJECTIVE: Metabolic and bariatric surgery has a definite role in the management of obese patients with type 2 diabetes mellitus (T2DM). There is also evidence of such surgery improving the health of type 1 diabetic (T1DM) patients. The aim of this paper is to explore the effect of metabolic and bariatric surgery on T1DM. MATERIALS AND METHODS: A comprehensive search of PubMed and Google Scholar was performed to identify relevant papers reporting metabolic and bariatric surgery effects on T1DM. A statistical analysis is applied after data synthesis. A forest plot and Pearson correlation are then calculated. RESULTS: Of the 567 papers that were identified, 558 articles did not fulfill the inclusion criteria and were therefore excluded. Nine studies involving 78 patients were selected for this metaanalysis. There was improvement in HBA1c (p value = 0.40), insulin dose (p value = 0.0001) and BMI (p value = 0.00001) after surgery. However, improvement in the HBA1c did not reach statistical significance. There was a weak correlation between postoperative insulin dose and BMI change after surgery (r = -0.177). There was a negligible correlation between HBA1c and BMI change after operations (r = -0.01). CONCLUSION: Current metabolic/bariatric surgery is improving T1DM in obese and morbidly obese patients. This is not exclusively related to excess weight loss (EWL) as previously thought. Therefore, there is a role for other factors, which are potential players to reproduce the same effect in nonobese T1DM patients.

Renopancreatic Transplantation: Evaluation of 15 Years in 131 Patients.

BACKGROUND: The most common multiple-organ transplant is the simultaneous pancreas-kidney transplantation (SPK). It is usually offered to patients who have insulin-dependent diabetes mellitus and those with diabetic nephropathy and renal failure that has already been established. In this study we present the results of 15 years of SPK in a transplant hospital center in Paraná, Brazil, and evaluated survival, immunosuppression, and transplant-related problems. METHODS: This study was a retrospective analysis of 131 SPK transplants performed at the Angelina Caron Hospital between January 2001 and December 2015. RESULTS: The mean age of SPK recipients was 34 years, with slight a predominance of males (50.4%). Mean graft ischemia time was 11 hours. Exocrine drainage was predominantly vesical, but this approach was abandoned after 2011. As for immunosuppression, induction was performed with basiliximab or thymoglobulin and maintained with prednisone, mycophenolate mofetil, tacrolimus, and/or sirolimus. Patient survival increased from 68.1% in 2001 to 2005 to 77.6% in 2011 to 2015. Graft survival at the end of the period was 85.7% for kidney and 75.5% for pancreas. The main surgery-derived problems for pancreas and kidney was thrombosis (15% and 6%, respectively). The main clinical problems were rejection of the pancreas (18.3%) and urinary infection of the kidney (33.3%). The main cause of death was intra-abdominal sepsis (11.4%). CONCLUSION: There was an improvement in survival rates over the time frame observed, but it remains necessary to adopt measures to reduce transplant-derived problems, including review of the antibiotic therapy protocol and measures to avoid graft thrombosis.

The effect of metabolic surgery on type 1 diabetes: meta-analysis

ABSTRACT Objective Metabolic and bariatric surgery has a definite role in the management of obese patients with type 2 diabetes mellitus (T2DM). There is also evidence of such surgery improving the health of type 1 diabetic (T1DM) patients. The aim of this paper is to explore the effect of metabolic and bariatric surgery on T1DM. Materials and methods A comprehensive search of PubMed and Google Scholar was performed to identify relevant papers reporting metabolic and bariatric surgery effects on T1DM. A statistical analysis is applied after data synthesis. A forest plot and Pearson correlation are then calculated. Results Of the 567 papers that were identified, 558 articles did not fulfill the inclusion criteria and were therefore excluded. Nine studies involving 78 patients were selected for this metaanalysis. There was improvement in HBA1c (p value = 0.40), insulin dose (p value = 0.0001) and BMI (p value = 0.00001) after surgery. However, improvement in the HBA1c did not reach statistical significance. There was a weak correlation between postoperative insulin dose and BMI change after surgery (r = -0.177). There was a negligible correlation between HBA1c and BMI change after operations (r = -0.01). Conclusion Current metabolic/bariatric surgery is improving T1DM in obese and morbidly obese patients. This is not exclusively related to excess weight loss (EWL) as previously thought. Therefore, there is a role for other factors, which are potential players to reproduce the same effect in nonobese T1DM patients.

En-Bloc Transplant of the Liver, Kidney and Pancreas: Experience from a Latin American Transplant Center.

BACKGROUND En-bloc transplantation is a surgical procedure in which multiple organs are transplanted simultaneously. It has some similarities with multi-organ transplantation but offers certain advantages. This report highlights the experience of our interdisciplinary group regarding the treatment and follow-up of patients who received en-bloc transplantation, with the aim of encouraging the development of this surgical technique. CASE REPORT The first case is a 38-year-old patient with type 1 diabetes mellitus, liver cirrhosis, and chronic kidney failure who received an en-bloc transplant of the liver, pancreas, and kidney with no intraoperative complications. He had a prolonged hospital stay due to anemia and systemic inflammatory response syndrome, which were resolved successfully. At follow-up, he had no requirement for insulin or for dialysis, or for new interventions. The second case describes a 48-year-old patient with type 2 diabetes mellitus, renal failure, and liver cirrhosis who received an en-bloc transplant of the liver, pancreas, and kidney with no complications. During the postoperative period, the patient suffered a possible episode of acute tubular necrosis, which evolved towards improvement, with a tendency to normal metabolic and renal functioning, with no additional events. The patient is currently in follow-up and is insulin-independent. CONCLUSIONS En-bloc transplantation is a safe procedure, which is technically simple and which achieves excellent results. This procedure is indicated in patients with end-stage renal disease, cirrhosis, and diabetes mellitus that is difficult to control.

Pancreas transplantation: review.

Vascularized pancreas transplantation is the only treatment that establishes normal glucose levels and normalizes glycosylated hemoglobin levels in type 1 diabetic patients. The first vascularized pancreas transplant was performed by William Kelly and Richard Lillehei, to treat a type 1 diabetes patient, in December 1966. In Brazil, Edison Teixeira performed the first isolated segmental pancreas transplant in 1968. Until the 1980s, pancreas transplants were restricted to a few centers of the United States and Europe. The introduction of tacrolimus and mycophenolate mofetil in 1994, led to a significant outcome improvement and consequently, an increase in pancreas transplants in several countries. According to the International Pancreas Transplant Registry, until December 31st, 2010, more than 35 thousand pancreas transplants had been performed. The one-year survival of patients and pancreatic grafts exceeds 95 and 83%, respectively. The better survival of pancreatic (86%) and renal (93%) grafts in the first year after transplantation is in the simultaneous pancreas-kidney transplant group of patients. Immunological loss in the first year after transplant for simultaneous pancreas-kidney, pancreas after kidney, and pancreas alone are 1.8, 3.7, and 6%, respectively. Pancreas transplant has 10 to 20% surgical complications requiring laparotomy. Besides enhancing quality of life, pancreatic transplant increases survival of uremic diabetic patient as compared to uremic diabetic patients on dialysis or with kidney transplantation alone.

Pancreas transplantation: review / Transplante de pâncreas: revisão

ABSTRACT Vascularized pancreas transplantation is the only treatment that establishes normal glucose levels and normalizes glycosylated hemoglobin levels in type 1 diabetic patients. The first vascularized pancreas transplant was performed by William Kelly and Richard Lillehei, to treat a type 1 diabetes patient, in December 1966. In Brazil, Edison Teixeira performed the first isolated segmental pancreas transplant in 1968. Until the 1980s, pancreas transplants were restricted to a few centers of the United States and Europe. The introduction of tacrolimus and mycophenolate mofetil in 1994, led to a significant outcome improvement and consequently, an increase in pancreas transplants in several countries. According to the International Pancreas Transplant Registry, until December 31st, 2010, more than 35 thousand pancreas transplants had been performed. The one-year survival of patients and pancreatic grafts exceeds 95 and 83%, respectively. The better survival of pancreatic (86%) and renal (93%) grafts in the first year after transplantation is in the simultaneous pancreas-kidney transplant group of patients. Immunological loss in the first year after transplant for simultaneous pancreas-kidney, pancreas after kidney, and pancreas alone are 1.8, 3.7, and 6%, respectively. Pancreas transplant has 10 to 20% surgical complications requiring laparotomy. Besides enhancing quality of life, pancreatic transplant increases survival of uremic diabetic patient as compared to uremic diabetic patients on dialysis or with kidney transplantation alone.

RESUMO O transplante vascularizado de pâncreas é o único tratamento que estabelece normoglicemia e normaliza os níveis séricos de hemoglobina glicosilada em pacientes diabéticos tipo 1. O primeiro transplante de pâncreas vascularizado foi realizado para tratar um paciente diabético tipo 1 em dezembro de 1966, por William Kelly e Richard Lillehei. No Brasil, Edison Teixeira realizou o primeiro transplante de pâncreas segmentar isolado em 1968. Até a década de 1980, os transplantes de pâncreas ficaram restritos a poucos centros dos Estados Unidos e da Europa. A introdução dos imunossupressores tacrolimo e micofenolato mofetila, a partir de 1994, propiciou a melhora significativa dos resultados e a consequente realização de transplantes em escala crescente em vários países. Segundo o Registro Internacional de Transplante de Pâncreas, foram realizados, até 31 de dezembro de 2010, mais de 35 mil transplantes de pâncreas. Sobrevida no primeiro ano dos pacientes e dos enxertos pancreáticos excede, respectivamente, 95 e 83%. A melhor sobrevida dos enxertos pancreático (86%) e renal (93%), no primeiro ano pós-transplante, está na categoria de transplante simultâneo de pâncreas e rim. As perdas imunológicas no primeiro ano pós-transplante para transplante simultâneo de pâncreas e rim, transplante de pâncreas após rim e transplante de pâncreas isolado foram, respectivamente, 1,8, 3,7, e 6%. O transplante de pâncreas apresenta de 10 a 20% de complicações cirúrgicas, necessitando laparotomia. O transplante de pâncreas, além de melhorar a qualidade de vida, proporciona o aumento da sobrevida em diabéticos urêmicos, comparados aos diabéticos em diálise ou transplantados renais.

Review of experimental attempts of islet allotransplantation in rodents: parameters involved and viability of the procedure.

The purpose of the present study was to organize the parameters involved in experimental allotransplantation in rodents to elaborate the most suitable model to supply the scarcity of islet donors. We used the PubMed database to systematically search for published articles containing the keywords "rodent islet transplantation" to review. We included studies that involved allotransplantation experiments with rodents' islets, and we reviewed the reference lists from the eligible publications that were retrieved. We excluded articles related to isotransplantation, autotransplantation and xenotransplantation, i.e., transplantation in other species. A total of 25 studies related to allotransplantation were selected for systematic review based on their relevance and updated data. Allotransplantation in rodents is promising and continues to develop. Survival rates of allografts have increased with the discovery of new immunosuppressive drugs and the use of different graft sites. These successes suggest that islet transplantation is a promising method to overcome the scarcity of islet donors and advance the treatment options for type 1 diabetes.

Pancreas transplantation from donors after cardiac death: an update of the UNOS database.

OBJECTIVE: There is reluctance to use donation after cardiac death (DCD) organs for fear of worse outcomes due to increased warm ischemia time. Extensive evidence to confirm the quality of DCD pancreas transplants is not manifest. METHODS: A united network for organ sharing database review of pancreas transplants performed between 1996 and 2012 was conducted. We compared outcomes and all demographic variables between donors after cardiac death and donors after brain death in pancreas transplantation. RESULTS: There were 320 DCD pancreas transplants and 20,448 donation after brain death pancreas transplants performed in the United States between 1996 and 2012. There was no statistically significant difference in graft survival or patient survival in pancreas transplantation in DCD versus donation after brain death donors measured at 1-year, 3-year, 5-year, 10-year, and 15-year intervals. There was no significant difference between donor and recipient age, race, sex, and body mass index (BMI) between the groups. There was no significant difference between the recipient ethnicity or time on wait list between the groups. CONCLUSIONS: Pancreata procured by DCD have comparable outcomes to those procured after brain death. Donation after cardiac death pancreas transplant is a viable method of increasing the donor pool, decreasing wait list mortality, and improving the quality of life for type 1 diabetic patients.

The effect of diabetes mellitus on chronic rhinosinusitis and sinus surgery outcome.

BACKGROUND: Patients with diabetes mellitus (DM) are known to be prone to infection. However, the association between diabetes and chronic rhinosinusitis (CRS) has not been well studied. We sought to determine the effects of DM on CRS culture results and quality of life (QOL) after functional endoscopic sinus surgery (FESS). METHODS: We conducted a retrospective cohort study. Adult CRS patients undergoing FESS were recruited from October 1, 2007 to December 31, 2011. Patient demographics, comorbidities, medication use, and Lund-Mackay CT scores were collected prior to FESS. Intraoperative culture was obtained. Preoperative and 1-month, 3-month, and 6-month postoperative QOL was measured by scores on the 22-item Sinonasal Outcome Test (SNOT-22). A mixed effects model was performed for analysis. RESULTS: Among the 376 CRS patients included, 19 patients (5.05%) had DM. Compared to non-DM patients, DM patients were significantly more likely to have Pseudomonas aeruginosa (26.32% vs 7.56%; p = 0.004) and Gram-negative rods (26.32% vs 8.96%; p = 0.013), but there was no significant difference in the prevalence of Staphylococcus aureus; DM patients were also significantly more likely to have nasal polyps and gastroesophageal reflux disease. Additionally, DM patients had significantly less improvement of postoperative SNOT-22 scores from baseline to 6-month follow-up than non-DM patients (adjusted mean = 11.14, 95% CI (0.14, 22.15), p = 0.047) after adjusting for all the other risk factors for CRS. CONCLUSION: DM patients may be prone to Gram-negative bacterial sinus infections, and have significantly worse short-term postoperative QOL. Special postoperative care may need to be considered in CRS patients with DM.

Charcot neuroarthropathy after simultaneous pancreas-kidney transplant.

BACKGROUND: Immunosuppressive regimen is associated with several metabolic adverse effects. Bone loss and fractures are frequent after transplantation and involve multifactorial mechanisms. METHODS: A retrospective analysis of 130 patients submitted to simultaneous pancreas-kidney transplantation (SPKT) and an identification of risk factors involved in de novo Charcot neuroarthropathy by multivariate analysis were used; P<0.05 was considered significant. RESULTS: Charcot neuroarthropathy was diagnosed in 4.6% of SPKT recipients during the first year. Cumulative glucocorticoid doses (daily dose plus methylprednisolone pulse) during the first 6 months both adjusted to body weight (>78 mg/kg) and not adjusted to body weight were associated with Charcot neuroarthropathy (P=0.001 and P<0.0001, respectively). Age, gender, race, time on dialysis, time of diabetes history, and posttransplantation hyperparathyroidism were not related to Charcot neuroarthropathy after SPKT. CONCLUSIONS: Glucocorticoids are the main risk factors for de novo Charcot neuroarthropathy after SPKT. Protocols including glucocorticoid avoidance or minimization should be considered.

The antidiabetic effect of mesenchymal stem cells is unrelated to their transdifferentiation potential but to their capability to restore Th1/Th2 balance and to modify the pancreatic microenvironment.

Type 1 diabetes mellitus (T1DM) is a chronic metabolic disease that results from cell-mediated autoimmune destruction of insulin-producing cells. In T1DM animal models, it has been shown that the systemic administration of multipotent mesenchymal stromal cells, also referred as to mesenchymal stem cells (MSCs), results in the regeneration of pancreatic islets. Mechanisms underlying this effect are still poorly understood. Our aims were to assess whether donor MSCs (a) differentiate into pancreatic ß-cells and (b) modify systemic and pancreatic pathophysiologic markers of T1DM. After the intravenous administration of 5 × 10(5) syngeneic MSCs, we observed that mice with T1DM reverted their hyperglycemia and presented no donor-derived insulin-producing cells. In contrast, 7 and 65 days post-transplantation, MSCs were engrafted into secondary lymphoid organs. This correlated with a systemic and local reduction in the abundance of autoaggressive T cells together with an increase in regulatory T cells. Additionally, in the pancreas of mice with T1DM treated with MSCs, we observed a cytokine profile shift from proinflammatory to antinflammatory. MSC transplantation did not reduce pancreatic cell apoptosis but recovered local expression and increased the circulating levels of epidermal growth factor, a pancreatic trophic factor. Therefore, the antidiabetic effect of MSCs intravenously administered is unrelated to their transdifferentiation potential but to their capability to restore the balance between Th1 and Th2 immunological responses along with the modification of the pancreatic microenvironment. Our data should be taken into account when designing clinical trials aimed to evaluate MSC transplantation in patients with T1DM since the presence of endogenous precursors seems to be critical in order to restore glycemic control.

Up-regulation of fas and fasL pro-apoptotic genes expression in type 1 diabetes patients after autologous haematopoietic stem cell transplantation.

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by T cell-mediated destruction of pancreatic ß cells, resulting in insulin deficiency and hyperglycaemia. Recent studies have described that apoptosis impairment during central and peripheral tolerance is involved in T1D pathogenesis. In this study, the apoptosis-related gene expression in T1D patients was evaluated before and after treatment with high-dose immunosuppression followed by autologous haematopoietic stem cell transplantation (HDI-AHSCT). We also correlated gene expression results with clinical response to HDI-AHSCT. We observed a decreased expression of bad, bax and fasL pro-apoptotic genes and an increased expression of a1, bcl-x(L) and cIAP-2 anti-apoptotic genes in patients' peripheral blood mononuclear cells (PBMCs) compared to controls. After HDI-AHSCT, we found an up-regulation of fas and fasL and a down-regulation of anti-apoptotic bcl-x(L) genes expression in post-HDI-AHSCT periods compared to pre-transplantation. Additionally, the levels of bad, bax, bok, fasL, bcl-x(L) and cIAP-1 genes expression were found similar to controls 2 years after HDI-AHSCT. Furthermore, over-expression of pro-apoptotic noxa at 540 days post-HDI-AHSCT correlated positively with insulin-free patients and conversely with glutamic acid decarboxylase autoantibodies (GAD65) autoantibody levels. Taken together, the results suggest that apoptosis-related genes deregulation in patients' PBMCs might be involved in breakdown of immune tolerance and consequently contribute to T1D pathogenesis. Furthermore, HDI-AHSCT modulated the expression of some apoptotic genes towards the levels similar to controls. Possibly, the expression of these apoptotic molecules could be applied as biomarkers of clinical remission of T1D patients treated with HDI-AHSCT therapy.