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1.
Artif Organs ; 45(9): 968-986, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34263961

RESUMO

Over the last few years, technological advances have led to tremendous improvement in the management of type 1 diabetes (T1D). Artificial pancreas systems have been shown to improve glucose control compared with conventional insulin pump therapy. However, clinically significant hypoglycemic and hyperglycemic episodes still occur with the artificial pancreas. Postprandial glucose excursions and exercise-induced hypoglycemia represent major hurdles in improving glucose control and glucose variability in many patients with T1D. In this regard, dual-hormone artificial pancreas systems delivering other hormones in addition to insulin (glucagon or amylin) may better reproduce the physiology of the endocrine pancreas and have been suggested as an alternative tool to overcome these limitations in clinical practice. In addition, novel ultra-rapid-acting insulin analogs with a more physiological time-action profile are currently under investigation for use in artificial pancreas devices, aiming to address the unmet need for further improvements in postprandial glucose control. This review article aims to discuss the current progress and future outlook in the development of novel ultra-rapid insulin analogs and dual-hormone closed-loop systems, which offer the next steps to fully closing the loop in the artificial pancreas.


Assuntos
Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Tipo 1/tratamento farmacológico , Pâncreas Artificial , Glicemia/análise , Glucagon/administração & dosagem , Humanos , Insulina/administração & dosagem , Sistemas de Infusão de Insulina , Polipeptídeo Amiloide das Ilhotas Pancreáticas/administração & dosagem
2.
Transplantation ; 105(11): 2490-2498, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33481552

RESUMO

BACKGROUND: Allosensitization has been reported after discontinuation of immunosuppression following graft failure in islet transplantation (ITx) recipients, though duration of its persistence is unknown. METHODS: We evaluated 35 patients with type 1 diabetes who received ITx, including 17 who developed graft failure (ITx alone, n = 13; ITx plus bone marrow-derived hematopoietic stem cells, n = 4) and 18 with persistent graft function. Panel-reactive antibody (PRA) was measured yearly for the duration of graft function within 1 y after graft failure at enrollment and yearly thereafter. RESULTS: In ITx alone graft failure patients, 61% (8/13) were PRA-positive at 6 y postgraft failure, and 46% (6/13) developed donor-specific anti-HLA antibodies (DSA to 2 ± 1 donors) during follow-up. The degree of sensitization was variable (cPRA ranging between 22% and 100% after graft failure). Allosensitization persisted for 7-15 y. Three subjects (3/13) were not allosensitized. In ITx plus bone marrow-derived hematopoietic stem cell recipients, cPRA-positivity (88%-98%) and DSA positivity persisted for 15 y in 75% (3/4) of subjects. CONCLUSIONS: Allosensitization was minimal while subjects remained on immunosuppression, but after discontinuation of immunosuppressive therapy, the majority of subjects (77%) became allosensitized with persistence of PRA positivity for up to 15 y. Persistence of allosensitization in this patient population is of clinical importance as it may result in longer transplant waiting list times for identification of a suitable donor in the case of requiring a subsequent transplant.


Assuntos
Transplante das Ilhotas Pancreáticas , Doadores de Tecidos , Aloenxertos , Rejeição de Enxerto , Sobrevivência de Enxerto , Antígenos HLA , Humanos , Transplante das Ilhotas Pancreáticas/efeitos adversos , Estudos Retrospectivos , Transplante Homólogo
3.
Stem Cells Transl Med ; 10(5): 660-673, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33400390

RESUMO

Acute respiratory distress syndrome (ARDS) in COVID-19 is associated with high mortality. Mesenchymal stem cells are known to exert immunomodulatory and anti-inflammatory effects and could yield beneficial effects in COVID-19 ARDS. The objective of this study was to determine safety and explore efficacy of umbilical cord mesenchymal stem cell (UC-MSC) infusions in subjects with COVID-19 ARDS. A double-blind, phase 1/2a, randomized, controlled trial was performed. Randomization and stratification by ARDS severity was used to foster balance among groups. All subjects were analyzed under intention to treat design. Twenty-four subjects were randomized 1:1 to either UC-MSC treatment (n = 12) or the control group (n = 12). Subjects in the UC-MSC treatment group received two intravenous infusions (at day 0 and 3) of 100 ± 20 × 106 UC-MSCs; controls received two infusions of vehicle solution. Both groups received best standard of care. Primary endpoint was safety (adverse events [AEs]) within 6 hours; cardiac arrest or death within 24 hours postinfusion). Secondary endpoints included patient survival at 31 days after the first infusion and time to recovery. No difference was observed between groups in infusion-associated AEs. No serious adverse events (SAEs) were observed related to UC-MSC infusions. UC-MSC infusions in COVID-19 ARDS were found to be safe. Inflammatory cytokines were significantly decreased in UC-MSC-treated subjects at day 6. Treatment was associated with significantly improved patient survival (91% vs 42%, P = .015), SAE-free survival (P = .008), and time to recovery (P = .03). UC-MSC infusions are safe and could be beneficial in treating subjects with COVID-19 ARDS.


Assuntos
Anti-Inflamatórios/uso terapêutico , COVID-19/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Citocinas/sangue , Método Duplo-Cego , Feminino , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Células-Tronco Mesenquimais , Pessoa de Meia-Idade , SARS-CoV-2/efeitos dos fármacos , Índice de Gravidade de Doença , Resultado do Tratamento , Cordão Umbilical/citologia
4.
Rev. bras. oftalmol ; 78(5): 334-337, Sept.-Oct. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1042385

RESUMO

Abstract We herein report a patient without risk factors who presented acute bilateral Irvine-Gass syndrome after uneventful phacoemulsification. The novelty of our case lies on the fact that the patient presented acute bilateral Irvine-Gass syndrome without a predisposing systemic disease. Even though Cystoid Macular Edema (CME) was somehow expected in the first eye because of the ocular history of trauma, prophylactic measures were not strong enough to avoid its development. Furthermore, those measures could not avoid developing CME in the second eye. A 44-years-old male who underwent cataract surgery in both eyes presented bilateral Irvine-Gass syndrome. Despite prophylactic measures, both eyes developed CME after uneventful cataract surgery. Regular treatment options could not solve the situation and intravitreal Anti-VEGF injections were needed. Bilateral cases of Irvine-Gass Syndrome are rare and generally associated with systemic risk factors. Patients who developed CME following their first cataract surgery should be counseled about the risks of developing the condition following surgery on the contralateral eye. On top of that, aggressive prophylactic measures should be encouraged to prevent CME in these cases.


Resumo Relatamos aqui um paciente sem fatores de risco que apresentou síndrome de Irvine-Gass bilateral aguda após facoemulsificação sem intercorrências. A novidade do nosso caso reside no fato de o paciente apresentar síndrome de Irvine-Gass bilateral aguda sem doença sistêmica predisponente. Embora o Edema Macular Cistoide (EMC) fosse de alguma forma esperado no primeiro olho por causa do histórico ocular de trauma, as medidas profiláticas não foram suficientemente fortes para evitar seu desenvolvimento. Além disso, essas medidas não puderam evitar o desenvolvimento de EMC no segundo olho. Homem de 44 anos submetido a cirurgia de catarata em ambos os olhos apresentou síndrome de Irvine-Gass bilateral. Apesar das medidas profiláticas, ambos os olhos desenvolveram EMC após a cirurgia de catarata sem intercorrências. As opções de tratamento regular não conseguiram resolver a situação e foram necessárias injeções intravítreas de Anti-VEGF. Casos de Síndrome de Irvine-Gass bilateral são raros e geralmente associados a fatores de risco sistêmicos. Os pacientes que desenvolveram EMC após a primeira cirurgia de catarata devem ser avisados sobre os riscos de desenvolver a doença após a cirurgia no olho contralateral. Além disso, medidas profiláticas agressivas devem ser incentivadas para evitar a EMC nesses casos.


Assuntos
Humanos , Masculino , Adulto , Edema Macular/etiologia , Facoemulsificação/efeitos adversos , Acuidade Visual , Edema Macular/tratamento farmacológico , Edema Macular/diagnóstico por imagem , Implante de Lente Intraocular , Inibidores da Angiogênese/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Tomografia de Coerência Óptica , Injeções Intravítreas
5.
Acta Diabetol ; 55(7): 715-722, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29654388

RESUMO

BACKGROUND: The immunosuppressive drug rapamycin may influence insulin sensitivity in insulin-responsive tissues. AIMS: This study aimed at evaluating the effectiveness of rapamycin pre-treatment before pancreatic islet allotransplantation (ITx) in patients with type 1 diabetes mellitus (T1DM). METHODS: Forty-one T1DM patients were studied. Thirteen patients with poor glycemic control underwent a short-term rapamycin treatment before ITx (Group 1), and they were compared to 28 patients undergoing ITx without rapamycin pre-treatment (Group 2). Outcomes were daily insulin requirement (DIR), fasting blood glucose, HbA1c, C-peptide and the SUITO index of beta-cell function. A subgroup of patients pre-treated with rapamycin before ITx underwent euglycemic hyperinsulinemic clamp with [6,6-2H2] glucose before and after ITx to evaluate insulin sensitivity. RESULTS: We found a significant reduction in DIR after rapamycin pre-treatment (- 8 ± 6 U/day, mean ± SD, p < 0.001) and 1 year after ITx. DIR reduction 1 year after ITx was greater in Group 1 as compared to Group 2 (- 37 ± 15 vs. - 19 ± 13 U/day, p = 0.005) and remained significant after adjusting for gender, age, glucose and baseline HbA1c (beta = 18.2 ± 5.9, p = 0.006). Fasting glucose and HbA1c significantly decreased 1 year after ITx in Group 1 (HbA1c: - 2.1 ± 1.4%, p = 0.002), while fasting C-peptide (+0.5 ± 0.3 nmol/l, p = 0.002) and SUITO index increased (+57.4 ± 39.7, p = 0.016), without differences between the two groups. Hepatic glucose production decreased after rapamycin pre-treatment (- 1.1 ± 1.1 mg/kg/min, p = 0.04) and after ITx (- 1.6 ± 0.6 mg/kg/min, p = 0.015), while no changes in peripheral glucose disposal were observed. CONCLUSIONS: Rapamycin pre-treatment before ITx succeeds in reducing insulin requirement, enhancing hepatic insulin sensitivity. This treatment may improve short-term ITx outcomes, possibly in selected patients with T1DM complicated by insulin resistance. CLINICAL TRIAL: Clinicaltrials.gov NCT01060605; NCT00014911.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/cirurgia , Insulina/uso terapêutico , Transplante das Ilhotas Pancreáticas , Sirolimo/administração & dosagem , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Idoso , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
6.
PLoS One ; 11(6): e0157245, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27285580

RESUMO

BACKGROUND: Allogeneic human islet transplantation is an effective therapy for the treatment of patients with Type 1 Diabetes (T1D). The low number of islet transplants performed worldwide and the different transplantation protocols used limit the identification of the most effective therapeutic options to improve the efficacy of this approach. METHODS: We present a retrospective analysis on the data collected from 44 patients with T1D who underwent islet transplantation at our institute between 2000 and 2007. Several variables were included: recipient demographics and immunological characteristics, donor and transplant characteristics, induction protocols, and additional medical treatment received. Immunosuppression was induced with anti-CD25 (Daclizumab), alone or in association with anti-tumor necrosis factor alpha (TNF-α) treatments (Etanercept or Infliximab), or with anti-CD52 (Alemtuzumab) in association with anti-TNF-α treatments (Etanercept or Infliximab). Subsets of patients were treated with Filgrastim for moderate/severe neutropenia and/or Exenatide for post prandial hyperglycemia. RESULTS: The analysis performed indicates a negative association between graft survival (c-peptide level ≥ 0.3 ng/ml) and islet infusion volume, with the caveat that, the progressive reduction of infusion volumes over the years has been paralleled by improved immunosuppressive protocols. A positive association is instead suggested between graft survival and administration of Exenatide and Filgrastim, alone or in combination. CONCLUSION: This retrospective analysis may be of assistance to further improve long-term outcomes of protocols for transplant of islets and other organs.


Assuntos
Filgrastim/uso terapêutico , Sobrevivência de Enxerto/efeitos dos fármacos , Fármacos Hematológicos/uso terapêutico , Hipoglicemiantes/uso terapêutico , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/efeitos dos fármacos , Peptídeos/uso terapêutico , Peçonhas/uso terapêutico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Daclizumabe , Exenatida , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/etiologia , Imunoglobulina G/uso terapêutico , Imunossupressores/uso terapêutico , Ilhotas Pancreáticas/fisiologia , Transplante das Ilhotas Pancreáticas/efeitos adversos , Pessoa de Meia-Idade , Neutropenia/tratamento farmacológico , Neutropenia/etiologia , Estudos Retrospectivos , Transplante Homólogo
7.
Pancreas ; 43(8): 1317-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25036907

RESUMO

OBJECTIVES: The effects of glucocorticoid during culture on human islet cells have been controversial. Exendin-4 (EX) enhances the insulin secretion and significantly improves clinical outcomes in islet cell transplantation. In this study, we examined the effects of glucocorticoids and EX on human islet cells during pretransplant culture. METHODS: Methylprednisolone (MP) and/or EX were added to the standard culture medium for clinical islet cell transplantation. Islets were cultured for 24 hours with 3 different conditions (control, no additives; MP alone; and MP + EX). ß-Cell fractional viability, cellular composition, multiple cytokine/chemokine production, multiple phosphorylation proteins, and glucose-induced insulin secretion were evaluated. RESULTS: Viable ß-cell survival in MP and MP + EX group was significantly higher than in the control group. Exendin-4 prevented MP-induced reduction of insulin secretion. Methylprednisolone supplementation to the culture medium decreased cytokine and chemokine production. Moreover, extracellular signal-regulated kinase 1/2 phosphorylation was significantly increased by MP and MP + EX. CONCLUSIONS: Glucocorticoid supplementation into culture media significantly decreased the cytokine/chemokine production and increased the extracellular signal-regulated kinase 1/2 phosphorylation, resulting in the improvement of human ß-cell survival. In addition, EX maintained the insulin secretion suppressed by MP. The supplementation of MP and EX together could be a useful strategy to create suitable human islets for transplantation.


Assuntos
Técnicas de Cultura de Células/métodos , Meios de Cultura/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Sobrevivência Celular , Quimiocinas/metabolismo , Citocinas/metabolismo , Exenatida , Glucose/farmacologia , Humanos , Mediadores da Inflamação , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metilprednisolona/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Peptídeos/farmacologia , Fosfoproteínas/análise , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Peçonhas/farmacologia
8.
Cell Transplant ; 20(10): 1649-51, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21396172

RESUMO

Pancreatic islet allotransplantation is an option for patients with unstable type 1 diabetes mellitus (T1DM). Major improvements in islet isolation techniques and the implementation of steroid-free immunosuppressive regimens can maintain insulin independence in the majority of T1DM for at least 1 year after transplantation. Recent studies have emphasized the impact of sirolimus on female reproductive tract. In this communication we report on the alterations of the female reproductive tract in 18 chronically immunosuppressed patients with T1DM following allogenic islet transplantation. Previous research has shown development of ovarian cysts in islet transplant patients receiving sirolimus. We extensively reevaluated this and other possible side effects on the female reproductive system. These side effects have been underestimated, although they are significant, requiring surgical or intensive medical treatment. Pre- and posttransplant gynecological evaluation should be performed to address the development of complications secondary to sirolimus in order to intervene sooner with alternative therapies.


Assuntos
Genitália Feminina/efeitos dos fármacos , Terapia de Imunossupressão/efeitos adversos , Imunossupressores/efeitos adversos , Transplante das Ilhotas Pancreáticas/métodos , Sirolimo/efeitos adversos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/cirurgia , Feminino , Humanos , Imunossupressores/uso terapêutico , Pessoa de Meia-Idade , Sirolimo/uso terapêutico
9.
Rev Diabet Stud ; 7(2): 144-57, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21060973

RESUMO

The bone marrow is an invaluable source of adult pluripotent stem cells, as it gives rise to hematopoietic stem cells, endothelial progenitor cells, and mesenchymal cells, amongst others. The use of bone marrow-derived stem cell (BMC) transplantation (BMT) may be of assistance in achieving tissue repair and regeneration, as well as in modulating immune responses in the context of autoimmunity and transplantation. Ongoing clinical trials are evaluating the effects of BMC to preserve functional beta-cell mass in subjects with type 1 and type 2 diabetes, and to favor engraftment and survival of transplanted islets. Additional trials are evaluating the impact of BMT (i.e., mesenchymal stem cells) on the progression of diabetes complications. This article reviews the progress in the field of BMC for the treatment of subjects with insulin-dependent diabetes, and summarizes clinical data of pilot studies performed over the last two decades at our research center by combining allogeneic islet transplantation with donor-specific BMC. Clinical data is summarized from pilot studies performed at our research center over the last two decades.


Assuntos
Transplante de Medula Óssea , Diabetes Mellitus/terapia , Insulina/metabolismo , Transplante de Células-Tronco Mesenquimais , Animais , Células da Medula Óssea/citologia , Diabetes Mellitus/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia
10.
Cell Transplant ; 18(10): 1247-59, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20003758

RESUMO

The initial success of islet transplantation (ITx) is followed by graft dysfunction (GDF) and insulin reintroduction. Exenatide, a GLP-1 agonist, increases insulin and decreases glucagon secretion and has potential for beta-cell regeneration. To improve functional islet mass, exenatide treatment was given to ITx recipients with GDF. The objective of this study was to assess metabolic and hormonal effects of exenatide in GDF. In this prospective, single-arm, nonrandomized study, 11 type 1 diabetes recipients of ITx with GDF had HbA1c, weight, insulin requirements, and 5-h mixed meal tolerance test (MMTT; with/without exenatide given before test) at baseline, 3, 6, and 12 months after initiating exenatide treatment. Baseline MMTT showed postprandial hyperglycemia and hyperglucagonemia. Daily exenatide treatment resulted in improved glucose, increased amylin/insulin ratio, and decreased proinsulin/insulin ratio as assessed by MMTT. Glucagon responses remained unchanged. Exenatide administration 1 h before MMTT showed decreased glucagon and glucose at 0 min and attenuation in their postprandial rise. Time-to-peak glucose was delayed, followed by insulin, proinsulin, amylin, and C-peptide, indicating glucose-driven insulin secretion. Five subjects completed 12-month follow-up. Glucose and glucagon suppression responses after MMTT with exenatide were no longer observed. Retrospective 3-month analysis of these subjects revealed higher and sustained glucagon levels that did not suppress as profoundly with exenatide administration, associated with higher glucose levels and increased C-peptide responses. In conclusion, Exenatide suppresses the abnormal postprandial hyperglucagonemia and hyperglycemia observed in GDF. Changes in amylin and proinsulin secretion may reflect more efficient insulin processing. Different degrees of responsiveness to exenatide were identified. These may help guide the clinical management of ITx recipients.


Assuntos
Hipoglicemiantes/farmacologia , Transplante das Ilhotas Pancreáticas , Peptídeos/farmacologia , Disfunção Primária do Enxerto/tratamento farmacológico , Peçonhas/farmacologia , Adulto , Amiloide/metabolismo , Área Sob a Curva , Peptídeo C/metabolismo , Demografia , Diabetes Mellitus Tipo 1/terapia , Exenatida , Feminino , Glucagon/metabolismo , Glucose/metabolismo , Humanos , Hiperglicemia/etiologia , Insulina/metabolismo , Secreção de Insulina , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Ilhotas Pancreáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Transplante Homólogo
11.
Transplantation ; 86(12): 1658-65, 2008 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-19104401

RESUMO

BACKGROUND: Progressive graft dysfunction (GDF) and loss of insulin independence (II) have been invariably observed in islet transplant recipients under the "Edmonton protocol." To reestablish II, we performed supplemental islet infusions (SI) in recipients of allogeneic islet transplant alone, displaying GDF. To improve the engraftment and long-term graft function of SI, exenatide (EXN) and etanercept treatment at islet infusion, and long-term EXN treatment were tested in a non-randomized pilot clinical trial. METHODS: Patients with GDF received SI under Edmonton-like immunosuppression with daclizumab induction, either without interventions (SI-control; n=5) or with EXN and etanercept treatment (SI-EXN; n=4). Clinical and metabolic profiles were assessed during 18-month follow-up. RESULTS: Long-term II (18 months) was observed in 100% of SI-EXN and in 20% of SI-control (P=0.04). SI-EXN subjects demonstrated restoration of function better than that seen after initial islet infusions. Comparison of SI-EXN and SI-control groups demonstrated better responses in SI-EXN subjects at 3 months post-SI. During the 18 months of follow-up, function was sustained in the SI-EXN subjects better than in SI-controls. Acute effects of EXN during mixed meal tolerance test and intravenous glucose tolerance test results in improved first and second phase insulin release in response to intravenous glucose tolerance test and suppressed postprandial hyperglucagonemia after mixed meal tolerance test. CONCLUSION: These results suggest that the combination of EXN and etanercept improve engraftment and long-term islet survival and function in subjects undergoing SI. This data, however, must be interpreted with some caution because of small sample size, lack of randomization, and sequential comparison with historical controls.


Assuntos
Hipoglicemiantes/uso terapêutico , Imunoglobulina G/uso terapêutico , Imunossupressores/uso terapêutico , Insulina/metabolismo , Transplante das Ilhotas Pancreáticas/métodos , Peptídeos/uso terapêutico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Peçonhas/uso terapêutico , Adulto , Glicemia/metabolismo , Peso Corporal , Peptídeo C/sangue , Etanercepte , Exenatida , Seguimentos , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Secreção de Insulina , Transplante das Ilhotas Pancreáticas/imunologia , Pessoa de Meia-Idade , Falha de Tratamento
12.
Transplantation ; 86(12): 1695-701, 2008 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-19104407

RESUMO

BACKGROUND: Only a minority of islet transplant recipients maintain insulin independence at 5 years under the Edmonton protocol of immunosuppression. New immunosuppressive strategies are required to improve long-term outcomes. MATERIALS AND METHODS: Three subjects with unstable type 1 diabetes mellitus underwent islet transplantation with alemtuzumab induction and sirolimus-tacrolimus maintenance for 3 months and then sirolimus-mycophenolic acid maintenance thereafter. Follow-up was more than 2 years. Comparison was with 16 historical subjects transplanted under the Miami version of the Edmonton protocol. RESULTS: Insulin independence was achieved in 2 of 3 alemtuzumab and 14 of 16 historical subjects. Those who did not achieve insulin independence only received a single islet infusion. Insulin-independence rates remained unchanged in the alemtuzumab group, but decreased from 14 of 16 (88%) to 6 of 16 (38%) in the historical group over 2 years. Insulin requirements increased in the historical group while remaining stable in the alemtuzumab group. Comparison of functional measures at 3 months suggested better engraftment with alemtuzumab (P=NS). Further comparison of alemtuzumab versus historical groups, up to 24 months, demonstrated significantly better: Mixed meal stimulation index (24 months, 1.0+/-0.08 [n=3] vs. 0.5+/-0.06 pmol/mL [n=6], P<0.01), mixed meal peak C-peptide (24 months, 5.0+/-0.5 [n=3] vs. 3.1+/-0.3 nmol/mL [n=6], P<0.05), HbA1c (24 months, 5.4+/-0.15 [n=3] vs. 6.3+/-0.12 pmol/mL [n=10], P<0.01). Administration of alemtuzumab was well tolerated. There was no increased incidence of infections in alemtuzumab subjects despite profound, prolonged lymphocyte depletion. CONCLUSIONS: Islet transplantation with alemtuzumab induction was well tolerated and resulted in improved short- and long-term outcomes. Further investigation is underway for validation.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Antineoplásicos/uso terapêutico , Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/imunologia , Adulto , Alemtuzumab , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Índice de Massa Corporal , Peptídeo C/sangue , Calcineurina , Esquema de Medicação , Quimioterapia Combinada , Seguimentos , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/uso terapêutico , Imunossupressores/uso terapêutico , Insulina/uso terapêutico , Sirolimo/uso terapêutico , Tacrolimo/uso terapêutico , Resultado do Tratamento
13.
Transplantation ; 86(9): 1161-7, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19005394

RESUMO

BACKGROUND: Health related quality of life (HRQoL) is one of the most important outcomes to measure effectiveness of an intervention, especially for islet transplantation in which benefits should outweigh risks of long-term immunosuppression. This study aimed to evaluate long-term effects of islet transplantation and to outline possible influential factors. METHODS: Forty islet transplant recipients who completed 344 Health Status Questionnaires (HSQ 2.0) and 384 Diabetes Quality of Life Questionnaires (DQoL) between 2000 and 2007 were retrospectively reviewed. Assessments were analyzed in pretransplantation period, then every 3 months after the first infusion for 18 months and every 6 months thereafter. The mean follow-up posttransplantation was 40.8+/-21.9 months (9-72 months). RESULTS: Sustained improvement in DQoL-impact score was observed at all time-points posttransplantation. Similarly, worry and satisfaction scales were significantly better than pretransplant evaluation for most time-points. Four of eight HSQ 2.0 scales demonstrated a significant improvement at some time-points. Longitudinal analysis, after adjustments for potential confounding factors, showed significantly sustained improvement in impact scale up to 72 months. Longer diabetes duration, higher insulin dosage, and occurrence of adverse events had negative effects on HRQoL. Single islet infusion or islet after kidney transplant recipients showed the lowest values in HSQ 2.0. In contrast, subjects on exenatide therapy had significantly higher HSQ 2.0 scores. CONCLUSIONS: Islet transplantation is associated with long-term improvement in HRQoL. Exenatide usage had a positive effect whereas single islet infusion, islet after kidney transplantation, longer diabetes duration, higher insulin dosage, and adverse events had a negative impact on HRQoL scores.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Nível de Saúde , Transplante das Ilhotas Pancreáticas , Qualidade de Vida , Adulto , Diabetes Mellitus Tipo 1/tratamento farmacológico , Relação Dose-Resposta a Droga , Exenatida , Feminino , Seguimentos , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Transplante das Ilhotas Pancreáticas/efeitos adversos , Transplante das Ilhotas Pancreáticas/fisiologia , Transplante das Ilhotas Pancreáticas/psicologia , Transplante de Rim , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Peptídeos/uso terapêutico , Qualidade de Vida/psicologia , Estudos Retrospectivos , Peçonhas/uso terapêutico
14.
Lab Invest ; 88(11): 1167-77, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18779781

RESUMO

Substantial amounts of nonendocrine cells are implanted as part of human islet grafts, and a possible influence of nonendocrine cells on clinical islet transplantation outcome has been postulated. There are currently no product release criteria specific for nonendocrine cells due to lack of available methods. The aims of this study were to develop a method for the evaluation of pancreatic ductal cells (PDCs) for clinical islet transplantation and to characterize them regarding phenotype, viability, and function. We assessed 161 human islet preparations using laser scanning cytometry (LSC/iCys) for phenotypic analysis of nonendocrine cells and flow cytometry (FACS) for PDC viability. PDC and beta-cells obtained from different density fractions during the islet cell purification were compared in terms of viability. Furthermore, we examined PDC ability to produce proinflammatory cytokines/chemokines, vascular endothelial growth factor (VEGF) and tissue factor (TF) relevant to islet graft outcome. Phenotypic analysis by LSC/iCys indicated that single staining for CK19 or CA19-9 was not enough for identifying PDCs, and that double staining for amylase and CK19 or CA19-9 allowed for quantitative evaluation of acinar cells and PDC content in human islet preparation. PDC showed a significantly higher viability than beta-cells (PDC vs beta-cell: 75.5+/-13.9 and 62.7+/-18.7%; P<0.0001). Although beta-cell viability was independent of its density, that of PDCs was higher as the density from which they were recovered increased. There was no correlation between PDCs and beta-cell viability (R(2)=0.0078). PDCs sorted from high-density fractions produced significantly higher amounts of proinflammatory mediators and VEGF, but not TF. We conclude that PDCs isolated from different fractions had different viability and functions. The precise characterization and assessment of these cells in addition to beta-cells in human islet cell products may be of assistance in understanding their contribution to islet engraftment and in developing strategies to enhance islet graft function.


Assuntos
Antígeno CA-19-9 , Células Secretoras de Insulina/citologia , Transplante das Ilhotas Pancreáticas , Queratina-19 , Ductos Pancreáticos/citologia , Animais , Diabetes Mellitus Experimental , Humanos , Células Secretoras de Insulina/classificação , Ilhotas Pancreáticas/citologia , Citometria de Varredura a Laser , Camundongos , Camundongos Nus , Fenótipo
15.
Transplantation ; 86(1): 36-45, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18622276

RESUMO

BACKGROUND: A current limitation of islet transplantation is reduced long-term graft function. The glucagon-like peptide-1 receptor agonist, exenatide (Byetta, Amylin Pharmaceuticals, CA) has properties that could improve existing islet function, prevent further loss of islet mass and possibly even stimulate islet regeneration. METHODS: This prospective study evaluated the safety, efficacy, and metabolic effects of exenatide in subjects with type 1 diabetes mellitus and islet allograft dysfunction requiring exogenous insulin. RESULTS: Sixteen subjects commenced exenatide, 12 continue (follow-up 214+/-57 days; range 108-287), four (25%) discontinued medication because of side effects. At 6 months, exogenous insulin was significantly reduced with stable glycemic control (0.15+/-0.02 vs. 0.11+/-0.025 U/kg per day; P<0.0001); three subjects discontinued insulin from 4, 5, and 9 U/day, respectively, two sustained insulin independence with A1c reduction below graft dysfunction criteria. Postprandial capillary blood glucose was significantly decreased (129.4+/-3.8 vs. 118.7+/-4.6 mg/dL; P<0.001), C-peptide and C-peptide-to-glucose ratio increased significantly by 5th and 6th months of treatment (ratio, 1.09+/-0.15 vs. 1.52+/-0.18; P<0.05). Weight loss more than 3 kg occurred in 8 of 12 (67%) subjects. Stimulation testing demonstrated improved glucose disposal and C-peptide secretion (glucose area under the curve 52,332+/-3,219 vs. 42,072+/-1,965; P=0.002 mg x min x dL, mixed meal stimulation index 0.50+/-0.06 vs. 0.66+/-0.09; P=0.03 pmol x mL), with marked suppression of glucagon secretion and progressive increase in amylin secretion. Side effects were more frequent and severe compared with published reports in type 2 diabetes, tolerated doses were lower. CONCLUSIONS: Exenatide was tolerated in this patient population after appropriate dose titration and there appeared to be gradual but sustained positive effects on glycemic control and islet graft function.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Peptídeos/uso terapêutico , Peçonhas/uso terapêutico , Adulto , Amiloide/sangue , Glicemia/efeitos dos fármacos , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/cirurgia , Exenatida , Estudos de Viabilidade , Glucagon/sangue , Rejeição de Enxerto/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Imunossupressores/uso terapêutico , Insulina/uso terapêutico , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Transplante das Ilhotas Pancreáticas , Pessoa de Meia-Idade , Peptídeos/efeitos adversos , Estudos Prospectivos , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento , Peçonhas/efeitos adversos
17.
Transplantation ; 85(4): 501-6, 2008 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-18347527

RESUMO

BACKGROUND: To investigate whether changes of nutritional status and behavior are associated with islet transplantation (ITx) and to assess their possible mechanisms. METHODS: In this observational study, 52 subjects with type 1 diabetes, 30 of whom received ITx, underwent nutritional assessments. The study consisted of questionnaires complemented by a dietary intake recording, anthropometric measurements, and body composition analysis. Laboratory tests were also reviewed as part of the follow up. RESULTS: After ITx, significant reductions in body weight (3.7 kg; P<0.0001), body mass index (1.39 kg/m2; P<0.0001), waist circumference (3.96 cm; P=0.006), and fat weight (3.28 kg; P<0.01) were observed. The average consumption of carbohydrate and protein were also lower than pretransplant, together with some micronutrients (vitamins B12 and B6, zinc, and phosphorus). Insulin administration and changes in A1C were not associated with a significant change in anthropometric measurements. Subjects on exenatide after ITx showed significantly lower weight and body mass index than those not taking exenatide. CONCLUSIONS: ITx is associated with modifications in nutritional behavior and status. Drugs and health conditions are likely to be at least in part responsible for these changes, but a voluntary modification of eating habits by the patients also plays a role. Strict monitoring of nutritional parameters, counseling by experts in nutrition, and multivitamin/mineral supplement after ITx could be of benefit to the patients.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/fisiologia , Transplante das Ilhotas Pancreáticas/psicologia , Estado Nutricional , Adulto , Índice de Massa Corporal , Transplante de Medula Óssea/fisiologia , Transplante de Medula Óssea/psicologia , Diabetes Mellitus Tipo 1/psicologia , Diabetes Mellitus Tipo 1/reabilitação , Dieta para Diabéticos , Ingestão de Energia , Exenatida , Seguimentos , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Entrevistas como Assunto , Transplante de Rim/fisiologia , Transplante de Rim/psicologia , Peptídeos/uso terapêutico , Percepção , Inquéritos e Questionários , Peçonhas/uso terapêutico
18.
Cell Transplant ; 17(12): 1295-304, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19364067

RESUMO

The objective of this study was to determine whether the combination therapy of intrapancreatic autologous stem cell infusion (ASC) and hyperbaric oxygen treatment (HBO) before and after ASC can improve islet function and metabolic control in patients with type 2 diabetes mellitus (T2DM). This prospective phase 1 study enrolled 25 patients with T2DM who received a combination therapy of intrapancreatic ASC and peri-infusion HBO between March 2004 and October 2006 at Stem Cells Argentina Medical Center Buenos Aires, Argentina. Clinical variables (body mass index, oral hypoglycemic drugs, insulin requirement) and metabolic variables (fasting plasma glucose, C-peptide, HbA1c, and calculation of C-peptide/glucose ratio) were assessed over quartile periods starting at baseline and up to 1 year follow-up after intervention. Means were calculated in each quartile period and compared to baseline. Seventeen male and eight female patients were enrolled. Baseline variables expressed as means +/- SEs were: age 55 +/- 2.14 years, diabetes duration 13.2 +/- 1.62 years, insulin dose 34.8 +/- 2.96 U/day, and BMI 27.11 +/- 0.51. All metabolic variables showed significant improvement when comparing baseline to 12 months follow-up, respectively: fasting glucose 205.6 +/- 5.9 versus 105.2 +/- 14.2 mg/dl, HbAlc 8.8 +/- 0.2 versus 6.0 +/- 0.4%, fasting C-peptide 1.5 +/- 0.2 versus 3.3 +/- 0.3 ng/ml, C-peptide/glucose ratio 0.7 +/- 0.2 versus 3.5 +/- 0.3, and insulin requirements 34.8 +/- 2.9 versus 2.5 +/- 6.7 U/day. BMI remained constant over the 1-year follow-up. Combined therapy of intrapancreatic ASC infusion and HBO can improve metabolic control and reduce insulin requirements in patients with T2DM. Further randomized controlled clinical trials will be required to confirm these findings.


Assuntos
Diabetes Mellitus Tipo 2/cirurgia , Oxigenoterapia Hiperbárica/métodos , Transplante de Células-Tronco/métodos , Adulto , Animais , Glicemia/metabolismo , Células da Medula Óssea , Peptídeo C/sangue , Terapia Combinada , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/terapia , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Oxigenoterapia Hiperbárica/efeitos adversos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Transplante de Células-Tronco/efeitos adversos , Transplante Autólogo
19.
N Engl J Med ; 355(13): 1318-30, 2006 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17005949

RESUMO

BACKGROUND: Islet transplantation offers the potential to improve glycemic control in a subgroup of patients with type 1 diabetes mellitus who are disabled by refractory hypoglycemia. We conducted an international, multicenter trial to explore the feasibility and reproducibility of islet transplantation with the use of a single common protocol (the Edmonton protocol). METHODS: We enrolled 36 subjects with type 1 diabetes mellitus, who underwent islet transplantation at nine international sites. Islets were prepared from pancreases of deceased donors and were transplanted within 2 hours after purification, without culture. The primary end point was defined as insulin independence with adequate glycemic control 1 year after the final transplantation. RESULTS: Of the 36 subjects, 16 (44%) met the primary end point, 10 (28%) had partial function, and 10 (28%) had complete graft loss 1 year after the final transplantation. A total of 21 subjects (58%) attained insulin independence with good glycemic control at any point throughout the trial. Of these subjects, 16 (76%) required insulin again at 2 years; 5 of the 16 subjects who reached the primary end point (31%) remained insulin-independent at 2 years. CONCLUSIONS: Islet transplantation with the use of the Edmonton protocol can successfully restore long-term endogenous insulin production and glycemic stability in subjects with type 1 diabetes mellitus and unstable control, but insulin independence is usually not sustainable. Persistent islet function even without insulin independence provides both protection from severe hypoglycemia and improved levels of glycated hemoglobin. (ClinicalTrials.gov number, NCT00014911 [ClinicalTrials.gov].).


Assuntos
Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas/métodos , Adulto , Glicemia/metabolismo , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/sangue , Estudos de Viabilidade , Seguimentos , Humanos , Hipoglicemiantes/uso terapêutico , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Infusões Intravenosas , Insulina/metabolismo , Insulina/uso terapêutico , Secreção de Insulina , Transplante das Ilhotas Pancreáticas/efeitos adversos , Transplante das Ilhotas Pancreáticas/normas , Isoanticorpos/sangue , Pessoa de Meia-Idade , Infecções Oportunistas/epidemiologia , Veia Porta , Reprodutibilidade dos Testes , Condicionamento Pré-Transplante/normas
20.
Transplantation ; 80(12): 1718-28, 2005 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-16378067

RESUMO

BACKGROUND: The success of sirolimus and low-dose tacrolimus in islet cell transplantation has influenced many transplant centers to utilize this novel regimen. The long-term safety and tolerability of this steroid-free immunosuppressive protocol for allogeneic islet transplantation has yet to be determined. METHODS: We transplanted 26 adult patients with long standing type 1 diabetes mellitus between April 2000 and June 2004. Immunosuppression consisted of induction with daclizumab and maintenance therapy with tacrolimus and sirolimus. Adverse events (AEs) in patients were followed and graded using the Common Terminology Criteria for Adverse Events, version 3.0 (National Cancer Institute). RESULTS: To date, the majority of patients were able to remain on the immunosuppression combination for up to 22+/-11 months. Four patients were successfully converted to Mycophenolate Mofetil due to tacrolimus-related toxicity. Withdrawal from immunosuppression was decided in four patients due to hypereosinophilic syndrome, parvovirus infection, aspiration pneumonia, and severe depression, respectively. Six patients required filgrastim therapy for neutropenia. Transient elevation of liver enzymes was observed in most patients early after islet infusion. Increased LDL in 20 patients required medical treatment. CONCLUSION: There was a varying range of AEs, most of them mild and self-limiting; however, some required urgent medical attention. The majority of patients were able to tolerate and remain on this effective regimen. To date, no deaths, cytomegalovirus disease, graft-versus-host disease, or posttransplant lymphoproliferative disease has been observed.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Terapia de Imunossupressão/efeitos adversos , Transplante das Ilhotas Pancreáticas/imunologia , Complicações Pós-Operatórias/induzido quimicamente , Adulto , Peptídeo C/sangue , Feminino , Humanos , Imunossupressores/efeitos adversos , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Homólogo/imunologia
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