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1.
Surg Endosc ; 38(7): 3948-3956, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38844730

RESUMO

INTRODUCTION: Total pancreatectomy with islet autotransplantation (TPIAT) treats refractory pain in chronic pancreatitis, prevents episodes of acute exacerbation, and mitigates postoperative brittle diabetes. The minimally invasive (MIS) approach offers a decreased surgical access trauma and enhanced recovery. Having established a laparoscopic TPIAT program, we adopted a robotic approach (R-TPIAT) and studied patient outcomes compared to open TPIAT. METHODS: Between 2013 and 2021, 61 adult patients underwent TPIAT after a comprehensive evaluation (97% chronic pancreatitis). Pancreatic islets were isolated on-site during the procedure. We analyzed and compared intraoperative surgical and islet characteristics, postoperative morbidity and mortality, and 1-year glycemic outcomes. RESULTS: MIS-TPIAT was performed in 41 patients (67%, 15 robotic and 26 laparoscopic), and was associated with a shorter mean length of intensive care unit stay compared to open TPIAT (2.9 vs 4.5 days, p = 0.002). R-TPIAT replaced laparoscopic TPIAT in 2017 as the MIS approach of choice and demonstrated decreased blood loss compared to open TPIAT (324 vs 843 mL, p = 0.004), similar operative time (609 vs 562 min), 30-day readmission rate (7% vs 15%), and 90-day complication rate (13% vs 20%). The glycemic outcomes including C-peptide detection at 1-year (73% vs 88%) and insulin dependence at 1-year (75% vs 92%) did not differ. The mean length of hospital stay after R-TPIAT was 8.6 days, shorter than for laparoscopic (11.5 days, p = 0.031) and open TPIAT (12.6 days, p = 0.017). Both MIS approaches had a 1-year mortality rate of 0%. CONCLUSIONS: R-TPIAT was associated with a 33% reduction in length of hospital stay (4-day benefit) compared to open TPIAT. R-TPIAT was similar to open TPIAT on measures of feasibility, safety, pain control, and 1-year glycemic outcomes. Our data suggest that robotic technology, a new component in the multidisciplinary therapy of TPIAT, is poised to develop into the primary surgical approach for experienced pancreatic surgeons.


Assuntos
Transplante das Ilhotas Pancreáticas , Pancreatectomia , Pancreatite Crônica , Procedimentos Cirúrgicos Robóticos , Transplante Autólogo , Humanos , Pancreatite Crônica/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Transplante das Ilhotas Pancreáticas/métodos , Masculino , Feminino , Pancreatectomia/métodos , Pessoa de Meia-Idade , Adulto , Laparoscopia/métodos , Tempo de Internação/estatística & dados numéricos , Estudos Retrospectivos , Duração da Cirurgia , Resultado do Tratamento , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
2.
Cell Transplant ; 33: 9636897241259433, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38877672

RESUMO

Islet transplantation may be the most efficient therapeutic technique for patients with type 1 diabetes mellitus (T1DM). However, the clinical application of this method is faced with numerous limitations, including isolated islet apoptosis, recipient rejection, and graft vascular reconstruction. Mesenchymal stem cells (MSCs) possess anti-apoptotic, immunomodulatory, and angiogenic properties. Here, we review recent studies on co-culture and co-transplantation of islets with MSCs. We have summarized the methods of preparation of co-transplantation, especially the merits of co-culture, and the effects of co-transplantation. Accumulating experimental evidence shows that co-culture of islets with MSCs promotes islet survival, enhances islet secretory function, and prevascularizes islets through various pretransplant preparations. This review is expected to provide a reference for exploring the use of MSCs for clinical islet co-transplantation.


Assuntos
Técnicas de Cocultura , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Transplante das Ilhotas Pancreáticas/métodos , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Ilhotas Pancreáticas/citologia , Animais , Técnicas de Cocultura/métodos , Diabetes Mellitus Tipo 1/terapia
3.
Sci Adv ; 10(23): eadk3081, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848367

RESUMO

Clinical outcomes for total-pancreatectomy followed by intraportal islet autotransplantation (TP-IAT) to treat chronic pancreatitis (CP) are suboptimal due to pancreas inflammation, oxidative stress during islet isolation, and harsh engraftment conditions in the liver's vasculature. We describe a thermoresponsive, antioxidant macromolecule poly(polyethylene glycol citrate-co-N-isopropylacrylamide) (PPCN) to protect islet redox status and function and to enable extrahepatic omentum islet engraftment. PPCN solution transitions from a liquid to a hydrogel at body temperature. Islets entrapped in PPCN and exposed to oxidative stress remain functional and support long-term euglycemia, in contrast to islets entrapped in a plasma-thrombin biologic scaffold. In the nonhuman primate (NHP) omentum, PPCN is well-tolerated and mostly resorbed without fibrosis at 3 months after implantation. In NHPs, autologous omentum islet transplantation using PPCN restores normoglycemia with minimal exogenous insulin requirements for >100 days. This preclinical study supports TP-IAT with PPCN in patients with CP and highlights antioxidant properties as a mechanism for islet function preservation.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Omento , Estresse Oxidativo , Transplante das Ilhotas Pancreáticas/métodos , Omento/metabolismo , Animais , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácido Cítrico/farmacologia , Humanos , Antioxidantes/farmacologia , Pancreatite Crônica/metabolismo , Pancreatite Crônica/cirurgia , Pancreatite Crônica/patologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Masculino , Transição de Fase
4.
J Vis Exp ; (208)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38912778

RESUMO

Pancreatic islet transplantation is an emerging treatment for type I diabetes; however, it is limited by donor matching and availability. Porcine islet xenotransplantation offers a promising alternative to allotransplantation, with the potential for large-scale production of on-demand, functional islets. The yield and viability of isolated islets is highly susceptible to the quality of the donor pancreas and the method of procurement, particularly the duration of warm-ischemia time. To improve organ preservation and subsequent islet yield and viability, we have developed a protocol for surgical perfusion and resection of the porcine pancreas. This protocol employs direct infrarenal aortic cannulation and organ perfusion to both minimize warm-ischemia time and simplify the procedure for operators who do not have extensive surgical expertise. Subsequent arterial perfusion of the pancreas via the aorta flushes stagnant blood from the microvasculature, thereby reducing thrombosis and oxidative damage to the tissue. This manuscript provides a detailed protocol for surgical perfusion and resection of the porcine pancreas, followed by islet isolation and purification.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Pâncreas , Perfusão , Animais , Suínos , Ilhotas Pancreáticas/citologia , Transplante das Ilhotas Pancreáticas/métodos , Perfusão/métodos , Pâncreas/cirurgia , Pâncreas/irrigação sanguínea , Pâncreas/citologia , Transplante Heterólogo/métodos
5.
Nat Commun ; 15(1): 5176, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890279

RESUMO

The longevity of grafts remains a major challenge in allogeneic transplantation due to immune rejection. Systemic immunosuppression can impair graft function and can also cause severe adverse effects. Here, we report a local immuno-protective strategy to enhance post-transplant persistence of allografts using a mesenchymal stem cell membrane-derived vesicle (MMV)-crosslinked hydrogel (MMV-Gel). MMVs are engineered to upregulate expression of Fas ligand (FasL) and programmed death ligand 1 (PD-L1). The MMVs are retained within the hydrogel by crosslinking. The immuno-protective microenvironment of the hydrogel protects allografts by presenting FasL and PD-L1. The binding of these ligands to T effector cells, the dominant contributors to graft destruction and rejection, results in apoptosis of T effector cells and generation of regulatory T cells. We demonstrate that implantation with MMV-Gel prolongs the survival and function of grafts in mouse models of allogeneic pancreatic islet cells and skin transplantation.


Assuntos
Proteína Ligante Fas , Hidrogéis , Transplante das Ilhotas Pancreáticas , Camundongos Endogâmicos C57BL , Transplante de Pele , Linfócitos T Reguladores , Transplante Homólogo , Animais , Hidrogéis/química , Camundongos , Proteína Ligante Fas/metabolismo , Proteína Ligante Fas/imunologia , Linfócitos T Reguladores/imunologia , Transplante das Ilhotas Pancreáticas/métodos , Transplante de Pele/métodos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/imunologia , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Rejeição de Enxerto/imunologia , Humanos , Masculino , Apoptose/efeitos dos fármacos
6.
Pediatr Transplant ; 28(5): e14813, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38895780

RESUMO

BACKGROUND: Total pancreatectomy with islet autotransplantation (TPIAT) is a potentially curative treatment for patients with chronic pancreatitis (CP) refractory to medical and endoscopic therapies. Patients often receive the initial follow-up medical care at the surgery-performing center, but then may follow up closer to where they live. We sought to describe the characteristics and outcomes of pediatric patients who underwent TPIAT at a national surgical referral center and were subsequently followed at our regional subspecialty center, the Children's Hospital Colorado. METHODS: We performed a retrospective analysis of baseline and outcomes data for the 10 pediatric patients who underwent TPIAT from 2007 to 2020 and received follow-up care at our institution. RESULTS: All patients had a diagnosis of CP, and nine of 10 patients had an identified underlying genetic risk factor. Insulin usage was common immediately following TPIAT, but at 1 year of follow-up, five of nine patients (55.6%) were insulin-independent and nine of nine had an HbA1c below 6.5%. For the four patients on insulin 1 year after TPIAT, total daily insulin dose ranged from 0.06 to 0.71 units/kg/day. All patients who underwent mixed meal tolerance testing had a robust peak C-peptide response at 1 year. There were significant improvements in nausea, school/work absences, narcotic dependence, and pancreas-related hospital admissions 1 year after TPIAT. CONCLUSIONS: Patients followed at our center had long-term improvements with low-insulin usage, detectable C-peptide, and improved pancreatitis-related outcomes after TPIAT. Pediatric patients who undergo TPIAT can be successfully co-managed in conjunction with the original surgery-performing center.


Assuntos
Transplante das Ilhotas Pancreáticas , Pancreatectomia , Pancreatite Crônica , Qualidade de Vida , Transplante Autólogo , Humanos , Pancreatite Crônica/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Masculino , Feminino , Estudos Retrospectivos , Criança , Adolescente , Resultado do Tratamento , Glicemia/análise , Glicemia/metabolismo , Estudos Longitudinais
7.
Front Immunol ; 15: 1391504, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887292

RESUMO

Diabetes is a prevalent chronic disease that traditionally requires severe reliance on medication for treatment. Oral medication and exogenous insulin can only temporarily maintain blood glucose levels and do not cure the disease. Most patients need life-long injections of exogenous insulin. In recent years, advances in islet transplantation have significantly advanced the treatment of diabetes, allowing patients to discontinue exogenous insulin and avoid complications.Long-term follow-up results from recent reports on islet transplantation suggest that they provide significant therapeutic benefit although patients still require immunotherapy, suggesting the importance of future transplantation strategies. Although organ shortage remains the primary obstacle for the development of islet transplantation, new sources of islet cells, such as stem cells and porcine islet cells, have been proposed, and are gradually being incorporated into clinical research. Further research on new transplantation sites, such as the subcutaneous space and mesenteric fat, may eventually replace the traditional portal vein intra-islet cell infusion. Additionally, the immunological rejection reaction in islet transplantation will be resolved through the combined application of immunosuppressant agents, islet encapsulation technology, and the most promising mesenchymal stem cells/regulatory T cell and islet cell combined transplantation cell therapy. This review summarizes the progress achieved in islet transplantation, and discusses the research progress and potential solutions to the challenges faced.


Assuntos
Transplante das Ilhotas Pancreáticas , Transplante das Ilhotas Pancreáticas/métodos , Humanos , Animais , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/cirurgia , Diabetes Mellitus Tipo 1/imunologia
9.
Stem Cell Res Ther ; 15(1): 188, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937834

RESUMO

Diabetes mellitus, a significant global public health challenge, severely impacts human health worldwide. The organoid, an innovative in vitro three-dimensional (3D) culture model, closely mimics tissues or organs in vivo. Insulin-secreting islet organoid, derived from stem cells induced in vitro with 3D structures, has emerged as a potential alternative for islet transplantation and as a possible disease model that mirrors the human body's in vivo environment, eliminating species difference. This technology has gained considerable attention for its potential in diabetes treatment. Despite advances, the process of stem cell differentiation into islet organoid and its cultivation demonstrates deficiencies, prompting ongoing efforts to develop more efficient differentiation protocols and 3D biomimetic materials. At present, the constructed islet organoid exhibit limitations in their composition, structure, and functionality when compared to natural islets. Consequently, further research is imperative to achieve a multi-tissue system composition and improved insulin secretion functionality in islet organoid, while addressing transplantation-related safety concerns, such as tumorigenicity, immune rejection, infection, and thrombosis. This review delves into the methodologies and strategies for constructing the islet organoid, its application in diabetes treatment, and the pivotal scientific challenges within organoid research, offering fresh perspectives for a deeper understanding of diabetes pathogenesis and the development of therapeutic interventions.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Organoides , Humanos , Organoides/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/citologia , Animais , Transplante das Ilhotas Pancreáticas/métodos , Diabetes Mellitus/terapia , Diabetes Mellitus/patologia , Diferenciação Celular
11.
Life Sci ; 351: 122812, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38862063

RESUMO

AIMS: Despite islet transplantation has proved a great potential to become the standard therapy for type 1 diabetes mellitus (T1DM), this approach remains limited by ischemia, hypoxia, and poor revascularization in early post-transplant period as well as inflammation and life-long host immune rejection. Here, we investigate the potential and mechanism of human amniotic mesenchymal stem cells (hAMSCs)-islet organoid to improve the efficiency of islet engraftment in immunocompetent T1DM mice. MAIN METHODS: We generated the hAMSC-islet organoid structure through culturing the mixture of hAMSCs and islets on 3-dimensional-agarose microwells. Flow cytometry, whole-body fluorescent imaging, immunofluorescence, Calcein-AM/PI staining, ELISA, and qPCR were used to assess the potential and mechanism of shielding hAMSCs to improve the efficiency of islet transplantation. KEY FINDINGS: Transplant of hAMSC-islet organoids results in remarkably better glycemic control, an enhanced glucose tolerance, and a higher ß cell mass in vivo compared with control islets. Our results show that hAMSCs shielding provides an immune privileged microenvironment for islets and promotes graft revascularization in vivo. In addition, hAMSC-islet organoids show higher viability and reduced dysfunction after exposure to hypoxia and inflammatory cytokines in vitro. Finally, our results show that shielding with hAMSCs leads to the activation of PKA-CREB-IRS2-PI3K and PKA-PDX1 signaling pathways, up-regulation of SIL1 mRNA levels, and down-regulation of MT1 mRNA levels in ß cells, which ultimately promotes the synthesis, folding and secretion of insulin, respectively. SIGNIFICANCE: hAMSC-islet organoids can evidently increase the efficiency of islet engraftment and might develop into a promising alternative for the clinical treatment of T1DM.


Assuntos
Âmnio , Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Organoides , Animais , Células-Tronco Mesenquimais/citologia , Camundongos , Humanos , Transplante das Ilhotas Pancreáticas/métodos , Diabetes Mellitus Experimental/terapia , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/citologia , Âmnio/citologia , Transplante de Células-Tronco Mesenquimais/métodos , Diabetes Mellitus Tipo 1/terapia , Camundongos Endogâmicos C57BL , Masculino
12.
J Immunol ; 212(12): 1971-1980, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38709159

RESUMO

Most pancreatic islets are destroyed immediately after intraportal transplantation by an instant blood-mediated inflammatory reaction (IBMIR) generated through activation of coagulation, complement, and proinflammatory pathways. Thus, effective mitigation of IBMIR may be contingent on the combined use of agents targeting these pathways for modulation. CD47 and thrombomodulin (TM) are two molecules with distinct functions in regulating coagulation and proinflammatory responses. We previously reported that the islet surface can be modified with biotin for transient display of novel forms of these two molecules chimeric with streptavidin (SA), that is, thrombomodulin chimeric with SA (SA-TM) and CD47 chimeric with SA (SA-CD47), as single agents with improved engraftment following intraportal transplantation. This study aimed to test whether islets can be coengineered with SA-TM and SA-CD47 molecules as a combinatorial approach to improve engraftment by inhibiting IBMIR. Mouse islets were effectively coengineered with both molecules without a detectable negative impact on their viability and metabolic function. Coengineered islets were refractory to destruction by IBMIR ex vivo and showed enhanced engraftment and sustained function in a marginal mass syngeneic intraportal transplantation model. Improved engraftment correlated with a reduction in intragraft innate immune infiltrates, particularly neutrophils and M1 macrophages. Moreover, transcripts for various intragraft procoagulatory and proinflammatory agents, including tissue factor, HMGB1 (high-mobility group box-1), IL-1ß, IL-6, TNF-α, IFN-γ, and MIP-1α, were significantly reduced in coengineered islets. These data demonstrate that the transient codisplay of SA-TM and SA-CD47 proteins on the islet surface is a facile and effective platform to modulate procoagulatory and inflammatory responses with implications for both autologous and allogeneic islet transplantation.


Assuntos
Antígeno CD47 , Inflamação , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Camundongos Endogâmicos C57BL , Trombomodulina , Animais , Masculino , Camundongos , Antígeno CD47/imunologia , Antígeno CD47/metabolismo , Inflamação/imunologia , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas/métodos , Estreptavidina
13.
Cells ; 13(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38786050

RESUMO

Allogeneic islet transplantation has become a standard therapy for unstable type 1 diabetes. However, considering the large number of type 1 diabetic patients, the shortage of donors is a serious issue. To address this issue, clinical islet xenotransplantation is conducted. The first clinical islet xenotransplantation was performed by a Swedish team using fetal pancreatic tissue. Thereafter, clinical trials of islet xenotransplantation were conducted in New Zealand, Russia, Mexico, Argentina, and China using neonatal pig islets. In clinical trials, fetal or neonatal pancreata are used because of the established reliable islet isolation methods. These trials demonstrate the method's safety and efficacy. Currently, the limited number of source animal facilities is a problem in terms of promoting islet xenotransplantation. This limitation is due to the high cost of source animal facilities and the uncertain future of xenotransplantation. In the United States, the first xenogeneic heart transplantation has been performed, which could promote xenotransplantation. In Japan, to enhance xenotransplantation, the 'Medical Porcine Development Association' has been established. We hope that xenogeneic transplantation will become a clinical reality, serving to address the shortage of donors.


Assuntos
Transplante das Ilhotas Pancreáticas , Transplante Heterólogo , Transplante das Ilhotas Pancreáticas/métodos , Animais , Humanos , Rejeição de Enxerto , Suínos , Resultado do Tratamento , Diabetes Mellitus Tipo 1/cirurgia , Diabetes Mellitus Tipo 1/terapia , Ensaios Clínicos como Assunto , Ilhotas Pancreáticas
14.
BMC Nephrol ; 25(1): 156, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724923

RESUMO

BACKGROUND: Islet transplantation is an effective treatment for diabetes or even its complications. Aim of this study is to investigate efficacy of biomaterial treated islet transplantation on treating diabetic nephropathy. METHODS: Male rats were randomly divided into 6 groups; Control, diabetic control, diabetic transplanted with untreated islets, with platelet rich plasma treated islets, with pancreatic islets homogenate treated islets, or with these biomaterials combination treated islets. Islets cultured with biomaterials and transplanted to diabetic rats. After 60 days, biochemical, oxidative stress, and stereological parameters were assessed. RESULTS: Serum albumin and BUN concentration, decreased and increased respectively, Oxidative stress of kidney impaired, kidney weight, volume of kidney, cortex, medulla, glomerulus, proximal and distal tubules, collecting ducts, vessels, inflammatory, necrotic and fibrotic tissue in diabetic group increased compared to control group (p < 0.001). In treated groups, especially pancreatic islets homogenate treated islets transplanting animals, there was significant changes in kidney weight, and volume of kidney, proximal and distal tubules, Henle's loop and collecting ducts compared with diabetic group (p = 0.013 to p < 0.001). Combination treated islets animals showed significant increase in vessel volume compared to diabetic group (p < 0.001). Necrotic and fibrotic tissue significantly decreased in islets treated than untreated islet animals, it was higher in pancreatic islets homogenate, and combination treated islets groups (p = 0.001). CONCLUSIONS: Biomaterials treated islets transplanting could improve diabetic nephropathy. Improvement of oxidative stress followed by controlling glucose level, and effects of growth factors presenting in biomaterials can be considered as capable underlying mechanism of ameliorating inflammatory, necrotic and fibrotic tissue volume.


Assuntos
Materiais Biocompatíveis , Diabetes Mellitus Experimental , Nefropatias Diabéticas , Transplante das Ilhotas Pancreáticas , Animais , Masculino , Ratos , Nefropatias Diabéticas/patologia , Transplante das Ilhotas Pancreáticas/métodos , Materiais Biocompatíveis/uso terapêutico , Ilhotas Pancreáticas/patologia , Estresse Oxidativo , Ratos Sprague-Dawley , Resultado do Tratamento
15.
Cell Transplant ; 33: 9636897241251621, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756050

RESUMO

Subcutaneous islet transplantation is a promising treatment for severe diabetes; however, poor engraftment hinders its prevalence. We previously revealed that a gelatin hydrogel nonwoven fabric (GHNF) markedly improved subcutaneous islet engraftment. We herein investigated whether the addition of adipose tissue-derived stem cells (ADSCs) to GHNF affected the outcome. A silicone spacer sandwiched between two GHNFs with (AG group) or without (GHNF group) ADSCs, or a silicone spacer alone (Silicone group) was implanted into the subcutaneous space of healthy mice at 6 weeks before transplantation, then diabetes was induced 7 days before transplantation. Syngeneic islets were transplanted into the pretreated space. Intraportal transplantation (IPO group) was also performed to compare the transplant efficiency. Blood glucose, intraperitoneal glucose tolerance, immunohistochemistry, and inflammatory mediators were evaluated. The results in the subcutaneous transplantation were compared using the Silicone group as a control. The results of the IPO group were also compared with those of the AG group. The AG group showed significantly better blood glucose changes than the Silicone and the IPO groups. The cure rate of AG group (72.7%) was the highest among the groups (GHNF; 40.0%, IPO; 40.0%, Silicone; 0%). The number of vWF-positive vessels in the subcutaneous space of the AG group was significantly higher than that in other groups before transplantation (P < 0.01). Lectin angiography also showed that the same results (P < 0.05). According to the results of the ADSCs tracing, ADSCs did not exist at the transplant site (6 weeks after implantation). The positive rates for laminin and collagen III constructed around the transplanted islets did not differ among groups. Inflammatory mediators were higher in the Silicone group, followed by the AG and GHNF groups. Pretreatment using bioabsorbable scaffolds combined with ADSCs enhanced neovascularization in subcutaneous space, and subcutaneous islet transplantation using GHNF with ADSCs was superior to intraportal islet transplantation.


Assuntos
Tecido Adiposo , Gelatina , Hidrogéis , Transplante das Ilhotas Pancreáticas , Animais , Transplante das Ilhotas Pancreáticas/métodos , Tecido Adiposo/citologia , Gelatina/química , Camundongos , Hidrogéis/química , Masculino , Diabetes Mellitus Experimental/terapia , Células-Tronco/citologia , Células-Tronco/metabolismo , Ilhotas Pancreáticas/citologia , Glicemia/metabolismo , Camundongos Endogâmicos C57BL
16.
Expert Rev Endocrinol Metab ; 19(3): 217-227, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693782

RESUMO

INTRODUCTION: Type 1 diabetes (T1D) mellitus is an autoimmune disease in which immune cells, predominantly effector T cells, destroy insulin-secreting beta-cells. Beta-cell destruction led to various consequences ranging from retinopathy and nephropathy to neuropathy. Different strategies have been developed to achieve normoglycemia, including exogenous glucose compensation, whole pancreas transplantation, islet transplantation, and beta-cell replacement. AREAS COVERED: The last two decades of experience have shown that indigenous glucose compensation through beta-cell regeneration and protection is a peerless method for T1D therapy. Tremendous studies have tried to find an unlimited source for beta-cell regeneration, on the one hand, and beta-cell protection against immune attack, on the other hand. Recent advances in stem cell technology, gene editing methods, and immune modulation approaches provide a unique opportunity for both beta-cell regeneration and protection. EXPERT OPINION: Pluripotent stem cell differentiation into the beta-cell is considered an unlimited source for beta-cell regeneration. Devising engineered pancreas-specific regulatory T cells using Chimeric Antigen Receptor (CAR) technology potentiates an effective immune tolerance induction for beta-cell protection. Beta-cell regeneration using pluripotent stem cells and beta-cell protection using pancreas-specific engineered regulatory T cells promises to develop a curative protocol in T1D.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Transplante das Ilhotas Pancreáticas , Regeneração , Humanos , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/fisiologia , Transplante das Ilhotas Pancreáticas/métodos , Animais , Células-Tronco Pluripotentes , Transplante de Pâncreas/métodos
17.
Sci Rep ; 14(1): 11640, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773268

RESUMO

Porcine islet xenotransplantation is a promising therapy for severe diabetes mellitus. Maintenance of the quality and quantity of porcine islets is important for the success of this treatment. Here, we aimed to elucidate the influence of relatively short-term (14 days) culture on adult porcine islets isolated from three micro-minipigs (P111, P112 and P121). Morphological characteristics of islets changed little after 14 days of culture. The viability of cultured islets was also maintained at a high level (> 80%). Furthermore, cultured islets exhibited similar glucose-stimulated insulin secretion and insulin content at Day 14 were preserved comparing with Day 1, while the expressions of Ins, Gcg and Sst were attenuated at Day 14. Xenotransplantation using diabetic nude mice showed no normalization of blood glucose but increased levels of plasma porcine C-peptide after the transplantation of 14 day cultured porcine islets. Histological assessment revealed that relatively short-term cultured porcine islets were successfully engrafted 56 days following transplantation. These data show that relatively short-term culture did not impair the quality of adult porcine islets in regard to function, morphology, and viability. Prevention of impairment of gene correlated with endocrine hormone is warranted for further improvement.


Assuntos
Insulina , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Transplante Heterólogo , Animais , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/citologia , Suínos , Transplante das Ilhotas Pancreáticas/métodos , Insulina/metabolismo , Camundongos , Camundongos Nus , Secreção de Insulina , Diabetes Mellitus Experimental/terapia , Glicemia/metabolismo , Porco Miniatura , Sobrevivência Celular , Peptídeo C/metabolismo , Peptídeo C/sangue
18.
Sci Rep ; 14(1): 12402, 2024 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-38811610

RESUMO

Evaluating the quality of isolated human islets before transplantation is crucial for predicting the success in treating Type 1 diabetes. The current gold standard involves time-intensive in vivo transplantation into diabetic immunodeficient mice. Given the susceptibility of isolated islets to hypoxia, we hypothesized that hypoxia present in islets before transplantation could indicate compromised islet quality, potentially leading to unfavorable outcomes. To test this hypothesis, we analyzed expression of 39 hypoxia-related genes in human islets from 85 deceased donors. We correlated gene expression profiles with transplantation outcomes in 327 diabetic mice, each receiving 1200 islet equivalents grafted into the kidney capsule. Transplantation outcome was post-transplant glycemic control based on area under the curve of blood glucose over 4 weeks. In linear regression analysis, DDIT4 (R = 0.4971, P < 0.0001), SLC2A8 (R = 0.3531, P = 0.0009) and HK1 (R = 0.3444, P = 0.0012) had the highest correlation with transplantation outcome. A multiple regression model of 11 genes increased the correlation (R = 0.6117, P < 0.0001). We conclude that assessing pre-transplant hypoxia in human islets via gene expression analysis is a rapid, viable alternative to conventional in vivo assessments. This approach also underscores the importance of mitigating pre-transplant hypoxia in isolated islets to improve the success rate of islet transplantation.


Assuntos
Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Humanos , Animais , Transplante das Ilhotas Pancreáticas/métodos , Camundongos , Ilhotas Pancreáticas/metabolismo , Diabetes Mellitus Experimental/terapia , Masculino , Diabetes Mellitus Tipo 1/metabolismo , Hipóxia/metabolismo , Feminino , Hipóxia Celular , Pessoa de Meia-Idade , Glicemia/metabolismo
19.
J Diabetes Res ; 2024: 5574968, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800586

RESUMO

Islet transplantation (ITx) is an established and safe alternative to pancreas transplantation for type 1 diabetes mellitus (T1DM) patients. However, most ITx recipients lose insulin independence by 3 years after ITx due to early graft loss, such that multiple donors are required to achieve insulin independence. In the present study, we investigated whether skeletal myoblast cells could be beneficial for promoting angiogenesis and maintaining the differentiated phenotypes of islets. In vitro experiments showed that the myoblast cells secreted angiogenesis-related cytokines (vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and stromal-derived factor-1α (SDF-1α)), contributed to maintenance of differentiated islet phenotypes, and enhanced islet cell insulin secretion capacity. To verify these findings in vivo, we transplanted islets alone or with myoblast cells under the kidney capsule of streptozotocin-induced diabetic mice. Compared with islets alone, the group bearing islets with myoblast cells had a significantly lower average blood glucose level. Histological examination revealed that transplants with islets plus myoblast cells were associated with a significantly larger insulin-positive area and significantly higher number of CD31-positive microvessels compared to islets alone. Furthermore, islets cotransplanted with myoblast cells showed JAK-STAT signaling activation. Our results suggest two possible mechanisms underlying enhancement of islet graft function with myoblast cells cotransplantation: "indirect effects" mediated by angiogenesis and "direct effects" of myoblast cells on islets via the JAK-STAT cascade. Overall, these findings suggest that skeletal myoblast cells enhance the function of transplanted islets, implying clinical potential for a novel ITx procedure involving myoblast cells for patients with diabetes.


Assuntos
Diabetes Mellitus Experimental , Insulina , Transplante das Ilhotas Pancreáticas , Mioblastos Esqueléticos , Neovascularização Fisiológica , Animais , Transplante das Ilhotas Pancreáticas/métodos , Diabetes Mellitus Experimental/metabolismo , Mioblastos Esqueléticos/transplante , Mioblastos Esqueléticos/metabolismo , Camundongos , Masculino , Insulina/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Camundongos Endogâmicos C57BL , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/irrigação sanguínea , Quimiocina CXCL12/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 1/cirurgia , Transdução de Sinais , Secreção de Insulina , Diferenciação Celular
20.
Cell Transplant ; 33: 9636897241249556, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38742734

RESUMO

Pancreatic islet transplantation is one of the clinical options for certain types of diabetes. However, difficulty in maintaining islets prior to transplantation limits the clinical expansion of islet transplantations. Our study introduces a dynamic culture platform developed specifically for primary human islets by mimicking the physiological microenvironment, including tissue fluidics and extracellular matrix support. We engineered the dynamic culture system by incorporating our distinctive microwell-patterned porous collagen scaffolds for loading isolated human islets, enabling vertical medium flow through the scaffolds. The dynamic culture system featured four 12 mm diameter islet culture chambers, each capable of accommodating 500 islet equivalents (IEQ) per chamber. This configuration calculates > five-fold higher seeding density than the conventional islet culture in flasks prior to the clinical transplantations (442 vs 86 IEQ/cm2). We tested our culture platform with three separate batches of human islets isolated from deceased donors for an extended period of 2 weeks, exceeding the limits of conventional culture methods for preserving islet quality. Static cultures served as controls. The computational simulation revealed that the dynamic culture reduced the islet volume exposed to the lethal hypoxia (< 10 mmHg) to ~1/3 of the static culture. Dynamic culture ameliorated the morphological islet degradation in long-term culture and maintained islet viability, with reduced expressions of hypoxia markers. Furthermore, dynamic culture maintained the islet metabolism and insulin-secreting function over static culture in a long-term culture. Collectively, the physiological microenvironment-mimetic culture platform supported the viability and quality of isolated human islets at high-seeding density. Such a platform has a high potential for broad applications in cell therapies and tissue engineering, including extended islet culture prior to clinical islet transplantations and extended culture of stem cell-derived islets for maturation.


Assuntos
Colágeno , Ilhotas Pancreáticas , Alicerces Teciduais , Humanos , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Alicerces Teciduais/química , Porosidade , Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/instrumentação , Transplante das Ilhotas Pancreáticas/métodos
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