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1.
Am J Transplant ; 22(3): 745-760, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34704345

RESUMO

A safe, efficacious, and clinically applicable immunosuppressive regimen is necessary for islet xenotransplantation to become a viable treatment option for diabetes. We performed intraportal transplants of wild-type adult porcine islets in 25 streptozotocin-diabetic cynomolgus monkeys. Islet engraftment was good in 21, partial in 3, and poor in 1 recipient. Median xenograft survival was 25 days with rapamycin and CTLA4Ig immunosuppression. Adding basiliximab induction and maintenance tacrolimus to the base regimen significantly extended median graft survival to 147 days (p < .0001), with three animals maintaining insulin-free xenograft survival for 265, 282, and 288 days. We demonstrate that this regimen suppresses non-Gal anti-pig antibody responses, circulating effector memory T cell expansion, effector function, and infiltration of the graft. However, a chronic systemic inflammatory state manifested in the majority of recipients with long-term graft survival indicated by increased neutrophil to lymphocyte ratio, IL-6, MCP-1, CD40, and CRP expression. This suggests that this immunosuppression regimen fails to regulate innate immunity and resulting inflammation is significantly associated with increased incidence and severity of adverse events making this regimen unacceptable for translation. Additional studies are needed to optimize a maintenance regimen for regulating the innate inflammatory response.


Assuntos
Diabetes Mellitus , Transplante das Ilhotas Pancreáticas , Animais , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Xenoenxertos , Humanos , Terapia de Imunossupressão , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Inflamação/etiologia , Transplante das Ilhotas Pancreáticas/métodos , Macaca fascicularis , Suínos , Transplante Heterólogo/métodos
2.
Sci Adv ; 10(1): eadi4919, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38181083

RESUMO

Cell-based therapies hold promise for many chronic conditions; however, the continued need for immunosuppression along with challenges in replacing cells to improve durability or retrieving cells for safety are major obstacles. We subcutaneously implanted a device engineered to exploit the innate transcapillary hydrostatic and colloid osmotic pressure generating ultrafiltrate to mimic interstitium. Long-term stable accumulation of ultrafiltrate was achieved in both rodents and nonhuman primates (NHPs) that was chemically similar to serum and achieved capillary blood oxygen concentration. The majority of adult pig islet grafts transplanted in non-immunosuppressed NHPs resulted in xenograft survival >100 days. Stable cytokine levels, normal neutrophil to lymphocyte ratio, and a lack of immune cell infiltration demonstrated successful immunoprotection and averted typical systemic changes related to xenograft transplant, especially inflammation. This approach eliminates the need for immunosuppression and permits percutaneous access for loading, reloading, biopsy, and recovery to de-risk the use of "unlimited" xenogeneic cell sources to realize widespread clinical translation of cell-based therapies.


Assuntos
Terapia de Imunossupressão , Primatas , Adulto , Animais , Humanos , Suínos , Xenoenxertos , Transplante Heterólogo , Biópsia
3.
Cells ; 12(8)2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37190056

RESUMO

Pluripotent stem (PS) cells enable the scalable production of tissue-specific derivatives with therapeutic potential for various clinical applications, including muscular dystrophies. Given the similarity to human counterparts, the non-human primate (NHP) is an ideal preclinical model to evaluate several questions, including delivery, biodistribution, and immune response. While the generation of human-induced PS (iPS)-cell-derived myogenic progenitors is well established, there have been no data for NHP counterparts, probably due to the lack of an efficient system to differentiate NHP iPS cells towards the skeletal muscle lineage. Here, we report the generation of three independent Macaca fascicularis iPS cell lines and their myogenic differentiation using PAX7 conditional expression. The whole-transcriptome analysis confirmed the successful sequential induction of mesoderm, paraxial mesoderm, and myogenic lineages. NHP myogenic progenitors efficiently gave rise to myotubes under appropriate in vitro differentiation conditions and engrafted in vivo into the TA muscles of NSG and FKRP-NSG mice. Lastly, we explored the preclinical potential of these NHP myogenic progenitors in a single wild-type NHP recipient, demonstrating engraftment and characterizing the interaction with the host immune response. These studies establish an NHP model system through which iPS-cell-derived myogenic progenitors can be studied.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , Camundongos , Células-Tronco Pluripotentes Induzidas/metabolismo , Distribuição Tecidual , Células-Tronco Pluripotentes/metabolismo , Músculo Esquelético/metabolismo , Primatas , Pentosiltransferases/metabolismo
4.
BMC Biochem ; 13: 17, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22962947

RESUMO

BACKGROUND: The molecular basis of the increased susceptibility of steatotic livers to warm ischemia/reperfusion (I/R) injury during transplantation remains undefined. Animal model for warm I/R injury was induced in obese Zucker rats. Lean Zucker rats provided controls. Two dimensional differential gel electrophoresis was performed with liver protein extracts. Protein features with significant abundance ratios (p < 0.01) between the two cohorts were selected and analyzed with HPLC/MS. Proteins were identified by Uniprot database. Interactive protein networks were generated using Ingenuity Pathway Analysis and GRANITE software. RESULTS: The relative abundance of 105 proteins was observed in warm I/R injury. Functional grouping revealed four categories of importance: molecular chaperones/endoplasmic reticulum (ER) stress, oxidative stress, metabolism, and cell structure. Hypoxia up-regulated 1, calcium binding protein 1, calreticulin, heat shock protein (HSP) 60, HSP-90, and protein disulfide isomerase 3 were chaperonins significantly (p < 0.01) down-regulated and only one chaperonin, HSP-1 was significantly upregulated in steatotic liver following I/R. CONCLUSION: Down-regulation of the chaperones identified in this analysis may contribute to the increased ER stress and, consequently, apoptosis and necrosis. This study provides an initial platform for future investigation of the role of chaperones and therapeutic targets for increasing the viability of steatotic liver allografts.


Assuntos
Fígado Gorduroso/metabolismo , Chaperonas Moleculares/metabolismo , Proteômica , Traumatismo por Reperfusão/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Bases de Dados de Proteínas , Regulação para Baixo , Eletroforese em Gel Bidimensional , Estresse do Retículo Endoplasmático , Fígado Gorduroso/patologia , Masculino , Espectrometria de Massas , Proteoma/metabolismo , Ratos , Ratos Zucker , Regulação para Cima , Isquemia Quente
5.
Exp Mol Pathol ; 93(3): 378-85, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23036474

RESUMO

Organ transplantation, an accepted treatment for end stage organ failure, is often complicated by allograft rejection and disease recurrence. In this review we will discuss the potential role of microRNAs in allograft immunity especially leading to rejection of the transplanted organ. microRNAs (miRNAs), originally identified in C. elegans, are short non-coding 21-24 nucleotide sequences that bind to its complementary sequences in functional messenger RNAs and inhibits post-translational processes through RNA duplex formation resulting in gene silencing (Lau et al., 2001). Gene specific translational silencing by miRNAs regulates pathways for immune responses such as development of innate immunity, inflammation, T-cell and B-cell differentiation and signaling that are implicated in various stages of allograft rejection. miRNAs also play a role in development of post-transplant complicacies like fibrosis, cirrhosis, carcinogenesis often leading to graft loss and poor patient outcome. Recent advancements in the methods for detecting and quantifying miRNA in tissue biopsies, as well as in serum and urine samples, has led to identification of specific miRNA signatures in patients with allograft rejection and have been utilized to predict allograft status and survival. Therefore, miRNAs play a significant role in post-transplant events including allograft rejection, disease recurrence and tumor development impacting patient outcome.


Assuntos
Rejeição de Enxerto/genética , Imunidade Inata/genética , MicroRNAs/fisiologia , Transplante de Órgãos , Imunologia de Transplantes/genética , Linfócitos B/imunologia , Diferenciação Celular , Inativação Gênica , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/imunologia , Humanos , Imunidade Inata/imunologia , Prognóstico , Linfócitos T/imunologia , Transplante Homólogo , Resultado do Tratamento
6.
Vaccine ; 40(15): 2342-2351, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35282925

RESUMO

An orally active vaccine capable of boosting SARS-CoV-2 immune responses in previously infected or vaccinated individuals would help efforts to achieve and sustain herd immunity. Unlike mRNA-loaded lipid nanoparticles and recombinant replication-defective adenoviruses, replicating vesicular stomatitis viruses with SARS-CoV-2 spike glycoproteins (VSV-SARS2) were poorly immunogenic after intramuscular administration in clinical trials. Here, by G protein trans-complementation, we generated VSV-SARS2(+G) virions with expanded target cell tropism. Compared to parental VSV-SARS2, G-supplemented viruses were orally active in virus-naive and vaccine-primed cynomolgus macaques, powerfully boosting SARS-CoV-2 neutralizing antibody titers. Clinical testing of this oral VSV-SARS2(+G) vaccine is planned.


Assuntos
COVID-19 , Rhabdoviridae , Vacinas Virais , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Lipossomos , Nanopartículas , Primatas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética
7.
Liver Transpl ; 17(2): 189-200, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21280192

RESUMO

Hepatic steatosis continues to present a major challenge in liver transplantation. These organs have been shown to have increased susceptibility to cold ischemia/reperfusion (CIR) injury in comparison with otherwise comparable lean livers; the mechanisms governing this increased susceptibility to CIR injury are not fully understood. Endoplasmic reticulum (ER) stress is an important link between hepatic steatosis, insulin resistance, and metabolic syndrome. In this study, we investigated ER stress signaling and blockade in the mediation of CIR injury in severely steatotic rodent allografts. Steatotic allografts from genetically leptin-resistant rodents had increased ER stress responses and increased markers of hepatocellular injury after liver transplantation into strain-matched lean recipients. ER stress response components were reduced by the chemical chaperone taurine-conjugated ursodeoxycholic acid (TUDCA), and this resulted in an improvement in the allograft injury. TUDCA treatment decreased nuclear factor kappa B activation and the proinflammatory cytokines interleukin-6 and interleukin-1ß. However, the predominant response was decreased expression of the ER stress cell death mediator [CCAAT/enhancer-binding protein homologous protein (CHOP)]. Furthermore, activation of inflammation-associated caspase-11 was decreased, and this linked ER stress/CHOP to proinflammatory cytokine production after steatotic liver transplantation. These data confirm ER stress in steatotic allografts and implicate this as a mediating mechanism of inflammation and hepatocyte death in the steatotic liver allograft.


Assuntos
Retículo Endoplasmático/metabolismo , Transplante de Fígado/efeitos adversos , Fígado/cirurgia , Traumatismo por Reperfusão/etiologia , Estresse Fisiológico , Fator 4 Ativador da Transcrição/metabolismo , Animais , Caspases/metabolismo , Modelos Animais de Doenças , Retículo Endoplasmático/efeitos dos fármacos , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado Gorduroso/cirurgia , Proteínas de Choque Térmico/metabolismo , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica , Ratos , Ratos Zucker , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais , Ácido Tauroquenodesoxicólico/farmacologia , Fatores de Tempo , Fator de Transcrição CHOP/metabolismo , Transplante Homólogo
8.
J Immunol ; 182(1): 309-18, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19109162

RESUMO

Alloimmunity to mismatched donor HLA-Ags and autoimmunity to self-Ags have been hypothesized to play an important role in immunopathogenesis of chronic rejection of transplanted organs. However, it is not known what role, if any, alloimmune response plays in inducing autoimmunity. To test whether Ab-developed posttransplantation to mismatched donor MHC induces autoimmunity and chronic rejection, we developed a murine model wherein anti-MHC class I Abs or control (C1.18.4/anti-keratin) were administered intrabronchially into native lungs. Animals receiving anti-MHC class I, but not control Abs, developed marked cellular infiltration around vessels and bronchiole of lung by day 15, followed by epithelial hyperplasia, fibrosis, and occlusion of the distal airways similar to chronic rejection following human lung transplantation. Lungs of mice receiving anti-MHC class I showed increased expression of chemokines, their receptors, and growth factors, and induced IL-17 as well as de novo Abs to self-Ags, K-alpha1 tubulin, and collagen V. IL-17 neutralization by anti-IL-17 resulted in reduction of autoantibody and lesions induced by anti-MHC class I Abs. Thus, our results indicate that Abs to donor MHC can induce autoimmunity, mediated by IL-17, which plays a pivotal role in chronic rejection postlung transplantation. Therefore, approaches to prevent autoimmunity should be considered for the treatment of chronic rejection postlung transplantation.


Assuntos
Autoanticorpos/administração & dosagem , Autoanticorpos/fisiologia , Doenças Autoimunes/imunologia , Bronquiolite Obliterante/imunologia , Rejeição de Enxerto/imunologia , Antígenos H-2/imunologia , Animais , Autoanticorpos/metabolismo , Doenças Autoimunes/patologia , Sítios de Ligação de Anticorpos , Bronquiolite Obliterante/patologia , Movimento Celular/imunologia , Doença Crônica , Fibrose , Rejeição de Enxerto/patologia , Antígenos H-2/administração & dosagem , Antígenos H-2/metabolismo , Hiperplasia , Imunidade Celular , Interleucina-17/antagonistas & inibidores , Interleucina-17/imunologia , Interleucina-17/fisiologia , Intubação Intratraqueal , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/imunologia , Transplante de Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Síndrome
9.
Sci Rep ; 11(1): 2340, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33504894

RESUMO

Cytokine profiling is a valuable tool for monitoring immune responses associated with disease and treatment. This study assessed the impact of sex and sedation on serum cytokines in healthy nonhuman primates (NHPs). Twenty-three cytokines were measured from serum using a bead-based multiplex assay. Assay validation for precision, sensitivity, recovery, linearity, and stability was performed. Samples from male and female cynomolgus and rhesus macaques either cooperating or sedated were compared. All cytokines except TNFα demonstrated acceptable sensitivity and precision, with variable recovery and linearity. IFNγ, IL-2, IL-5, IL-6, IL-8, IL-12/23 (p40), IL-13, IL-15, MCP-1, TGFα, VEGF met acceptance criteria; G-CSF, IL-4, IL-10, MIP1α, sCD40L were marginal. Higher cytokine levels were observed in females and cytokine levels were blunted in sedated NHPs when compared to awake cooperating NHPs. Significant differences observed in cytokines related to sex, species, or imposed by handling highlight the importance of model design on translational relevance for clinical settings.


Assuntos
Citocinas/sangue , Macaca mulatta/metabolismo , Animais , Citocinas/metabolismo , Feminino , Imunoensaio , Macaca mulatta/sangue , Macaca mulatta/imunologia , Masculino , Reprodutibilidade dos Testes , Caracteres Sexuais
10.
iScience ; 24(12): 103421, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34877488

RESUMO

The obesity epidemic significantly contributes to overall morbidity and mortality. Bariatric surgery is the gold standard treatment for obesity and metabolic dysfunction, yet the mechanisms by which it exerts metabolic benefit remain unclear. Here, we demonstrate a model of vertical sleeve gastrectomy (VSG) in nonhuman primates (NHP) that mimics the complexity and outcomes in humans. We also show that VSG confers weight loss and durable metabolic benefit, where equivalent caloric intake in shams resulted in significant weight gain following surgery. Furthermore, we show that VSG is associated with early, weight-independent increases in bile acids, short-chain fatty acids, and reduced visceral adipose tissue (VAT) inflammation with a polarization of VAT-resident immunocytes toward highly regulatory myeloid cells and Tregs. These data demonstrate that this strongly translational NHP model can be used to interrogate factors driving successful intervention to unravel the interplay between physiologic systems and improve therapies for obesity and metabolic syndrome.

11.
Transplantation ; 104(2): 259-269, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31385927

RESUMO

BACKGROUND: We have utilized a noninvasive technique for measuring the partial pressure of oxygen (pO2) in alginate microcapsules implanted intraperitoneally in healthy nonhuman primates (NHPs). Average pO2 is important for determining if a transplant site and capsules with certain passive diffusion characteristics can support the islet viability, metabolic activity, and dose necessary to reverse diabetes. METHODS: Perfluoro-15-crown-5-ether alginate capsules were infused intraperitoneally into 3 healthy NHPs. Peritoneal pO2 levels were measured on days 0 and 7 using fluorine-19 magnetic resonance relaxometry and a fiber-optic probe. Fluorine-19 MRI was used to determine the locations of capsules within the peritoneal space on days 0 and 7. Gross and histologic evaluations of the capsules were used to assess their biocompatibility postmortem. RESULTS: At day 0 immediately after infusion of capsules equilibrated to room air, capsules were concentrated near the infusion site, and the pO2 measurement using magnetic resonance relaxometry was 147 ± 9 mm Hg. On day 7 after capsules were dispersed throughout the peritoneal cavity, the pO2 level was 61 ± 11 mm Hg. Measurements using the fiber-optic oxygen sensor were 132 ± 7.5 mm Hg (day 0) and 89 ± 6.1 mm Hg (day 7). Perfluoro-15-crown-5-ether capsules retrieved on day 7 were intact and free-floating without host cell attachment, although the numbers of peritoneal CD20 B cells, CD4 and CD8 T cells, and CD14 macrophages increased consistent with a mild foreign body reaction. CONCLUSIONS: The peritoneal pO2 of normal NHPs is relatively low and we predict would decrease further when encapsulated islets are transplanted intraperitoneally.


Assuntos
Alginatos/farmacologia , Diabetes Mellitus Experimental/cirurgia , Imagem por Ressonância Magnética de Flúor-19/métodos , Transplante das Ilhotas Pancreáticas/métodos , Consumo de Oxigênio/fisiologia , Oxigênio/metabolismo , Cavidade Peritoneal/cirurgia , Animais , Cápsulas , Diabetes Mellitus Experimental/metabolismo , Feminino , Sobrevivência de Enxerto , Macaca mulatta , Pressão Parcial
12.
Nat Commun ; 10(1): 3495, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375697

RESUMO

Immune tolerance to allografts has been pursued for decades as an important goal in transplantation. Administration of apoptotic donor splenocytes effectively induces antigen-specific tolerance to allografts in murine studies. Here we show that two peritransplant infusions of apoptotic donor leukocytes under short-term immunotherapy with antagonistic anti-CD40 antibody 2C10R4, rapamycin, soluble tumor necrosis factor receptor and anti-interleukin 6 receptor antibody induce long-term (≥1 year) tolerance to islet allografts in 5 of 5 nonsensitized, MHC class I-disparate, and one MHC class II DRB allele-matched rhesus macaques. Tolerance in our preclinical model is associated with a regulatory network, involving antigen-specific Tr1 cells exhibiting a distinct transcriptome and indirect specificity for matched MHC class II and mismatched class I peptides. Apoptotic donor leukocyte infusions warrant continued investigation as a cellular, nonchimeric and translatable method for inducing antigen-specific tolerance in transplantation.


Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Tolerância Imunológica , Transplante das Ilhotas Pancreáticas/efeitos adversos , Linfócitos T Reguladores/transplante , Transferência Adotiva , Aloenxertos/imunologia , Animais , Apoptose/imunologia , Modelos Animais de Doenças , Feminino , Rejeição de Enxerto/imunologia , Humanos , Imunossupressores/uso terapêutico , Ilhotas Pancreáticas/imunologia , Macaca mulatta , Masculino , Linfócitos T Reguladores/imunologia , Doadores de Tecidos , Transplante Homólogo/efeitos adversos
13.
Transpl Immunol ; 18(3): 260-3, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18047935

RESUMO

The long term survival of human lung allograft is hampered by the occurrence of chronic rejection, Bronchiolitis Obliterans Syndrome (BOS). This end-stage disease is normally diagnosed clinically by using the pulmonary function tests. This results in delay of BOS diagnosis and consequently prevents early intervention. It is generally accepted that alloimmunity plays an important role in chronic rejection of the allograft. In this study we analyzed serial serum samples from BOS+ and BOS- patients for sCD30 levels to determine the role of sCD30 to predict the onset of BOS. In contrast to BOS negative patients and normal subjects, 6 out of 9 BOS+ patients (p<0.05) studied had an increase in the sCD30 levels. Significantly, the rise was noted 7.57+/-2.63 months before the clinical diagnosis was evident. Therefore, we propose that the rise in serum sCD30 levels can be used as a marker for the detection of patients who are at risk of development of BOS.


Assuntos
Bronquiolite Obliterante/diagnóstico , Rejeição de Enxerto/diagnóstico , Antígeno Ki-1/sangue , Transplante de Pulmão/imunologia , Adulto , Bronquiolite Obliterante/complicações , Bronquiolite Obliterante/imunologia , Feminino , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Humanos , Antígeno Ki-1/imunologia , Pulmão , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória
14.
Cell Stem Cell ; 22(1): 78-90.e4, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29304344

RESUMO

Successful strategies for treating type 1 diabetes need to restore the function of pancreatic beta cells that are destroyed by the immune system and overcome further destruction of insulin-producing cells. Here, we infused adeno-associated virus carrying Pdx1 and MafA expression cassettes through the pancreatic duct to reprogram alpha cells into functional beta cells and normalized blood glucose in both beta cell-toxin-induced diabetic mice and in autoimmune non-obese diabetic (NOD) mice. The euglycemia in toxin-induced diabetic mice and new insulin+ cells persisted in the autoimmune NOD mice for 4 months prior to reestablishment of autoimmune diabetes. This gene therapy strategy also induced alpha to beta cell conversion in toxin-treated human islets, which restored blood glucose levels in NOD/SCID mice upon transplantation. Hence, this strategy could represent a new therapeutic approach, perhaps complemented by immunosuppression, to bolster endogenous insulin production. Our study thus provides a potential basis for further investigation in human type 1 diabetes.


Assuntos
Reprogramação Celular , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/terapia , Terapia Genética , Células Secretoras de Glucagon/patologia , Células Secretoras de Insulina/patologia , Aloxano , Animais , Glicemia , Dependovirus/metabolismo , Perfilação da Expressão Gênica , Glucagon/metabolismo , Células Secretoras de Glucagon/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Hiperglicemia/complicações , Hiperglicemia/patologia , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Lectinas Tipo C , Camundongos Endogâmicos C57BL , Camundongos SCID , Receptores Imunológicos/metabolismo , Transativadores/metabolismo
15.
Transplantation ; 82(2): 180-7, 2006 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-16858280

RESUMO

BACKGROUND: In recent years, transplantation of islets and pancreas has become a viable option for patients debilitated with type I diabetes. The success of islet transplantation has been attributed to the ability to isolate high quality islets for transplantation and capacity to maintain the recipient's immunosuppressive levels within a specific target range following transplantation. The purpose of this study was to determine the role of pretransplant sensitization to human leukocyte antigen (HLA) in islet transplantation. METHODS: We retrospectively analyzed seven patients that were transplanted with islets under the auspices of the Juvenile Diabetes Research Foundation and Islet Cell Resource Center/National Institutes of Health. Humoral sensitization towards donor antigens both prior to and following islet transplantation was detected by FLOW panel reactive antibodies (PRA) and donor-specific cellular sensitization was detected by performing enzyme-linked immunospot assay analysis for cytokines interferon-gamma and interleukin-2. RESULTS: Our analysis demonstrates that humoral and cellular sensitization to histocompatibility antigens prior to and after islet transplantation are associated with the failure of transplanted islets CONCLUSION: Patient selection based on sensitization to donor HLA may be one of the factors crucial for the success of islet transplant. Further, in some patients, rejection of islets can be associated with sensitization to mismatched donor histocompatibility antigens.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Histocompatibilidade/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Diabetes Mellitus Tipo 1/sangue , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Insulina/sangue , Transplante Homólogo , Resultado do Tratamento
16.
J Gastrointest Surg ; 10(3): 357-64, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16504880

RESUMO

Hepatic cryoablation can produce acute lung injury, with activation of nuclear factor (NF)-kappaB in the remnant liver and lungs, production of C-X-C chemokines, and neutrophil infiltration of the lungs. Activated complement stimulates NF-kappaB and cytokine secretion from Kupffer cells. The role of complement in the development of acute lung injury after cryoablation was examined using HLL transgenic mice (5'HIV-LTR-Luciferase gene; 5' HIV-LTR is an NF-kappaB-dependent promoter). Total complement depletion was achieved with preoperative administration of cobra venom factor (CVF). After hepatic cryoablation, bioluminescent NF-kappaB activity increased in the nonablated liver remnant by 4 hours in both control (119,093 +/- 22,808 net RLU/mg protein) and CVF-treated mice (117,722 +/- 14,932) from cumulative baseline (657 +/- 90, P < 0.0001). In the lung, complement-depletion induced significantly greater increases in NF-kappaB activation at both early and later times. Likewise, chemokines were higher in complement-depleted mice relative to controls (KC: 493 +/- 43 versus 269 +/- 29 pg/mg protein, P < 0.001; MIP-2: 171 +/- 29 versus 64 +/- 13 pg/mg protein, P < 0.0001). Pulmonary myeloperoxidase activity was equivalent at 24 hours, but complement-depletion caused a significantly more rapid influx of neutrophils. Complement depletion results in increased pulmonary inflammation following liver cryo injury via relative upregulation of NF-kappaB activity. Activated complement is not the initiator of the systemic inflammatory response; in fact, downstream components of the complement cascade may diminish subsequent inflammation.


Assuntos
Proteínas do Sistema Complemento/metabolismo , Criocirurgia , Hepatopatias/cirurgia , Pneumonia/imunologia , Análise de Variância , Animais , Quimiocinas/imunologia , Medições Luminescentes , Camundongos , Camundongos Transgênicos , Modelos Animais , NF-kappa B/imunologia
17.
Endocrinology ; 157(4): 1348-56, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26872091

RESUMO

Although islet transplantation is an effective treatment for severe diabetes, its broad application is greatly limited due to a shortage of donor islets. Suppression of TGFß receptor signaling in ß-cells has been shown to increase ß-cell proliferation in mice, but has not been rigorously examined in humans. Here, treatment of human islets with a TGFß receptor I inhibitor, SB-431542 (SB), significantly improved C-peptide secretion by ß-cells, and significantly increased ß-cell number by increasing ß-cell proliferation. In addition, SB increased cell-cycle activators and decreased cell-cycle suppressors in human ß-cells. Transplantation of SB-treated human islets into diabetic immune-deficient mice resulted in significant improvement in blood glucose control, significantly higher serum and graft insulin content, and significantly greater increases in ß-cell proliferation in the graft, compared with controls. Thus, our data suggest that transient suppression of TGFß receptor signaling may improve the outcome of human islet transplantation, seemingly through increasing ß-cell number and function.


Assuntos
Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais/fisiologia , Animais , Benzamidas/farmacologia , Glicemia/metabolismo , Western Blotting , Peptídeo C/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Dioxóis/farmacologia , Feminino , Humanos , Insulina/sangue , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Camundongos Endogâmicos NOD , Camundongos SCID , Microscopia Confocal , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transplante Heterólogo
18.
Transplant Direct ; 2(10): e105, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27795987

RESUMO

OBJECTIVE: The aim of this study was to assess short-term and long-term results of the pancreatic islet transplantation using the Edmonton protocol at the University of Chicago. MATERIALS AND METHODS: Nine patients underwent pancreatic islet cell transplantation using the Edmonton Protocol; they were followed up for 10 years after initial islet transplant with up to 3 separate islet infusions. They were given induction treatment using an IL-2R antibody and their maintenance immunosuppression regimen consisted of sirolimus and tacrolimus. RESULTS: Nine patients received a total of 18 islet infusions. Five patients dropped out in the early phase of the study. Greater than 50% drop-out and noncompliance rate resulted from both poor islet function and recurrent side effects of immunosuppression. The remaining 4 (44%) patients stayed insulin free with intervals for at least over 5 years (cumulative time) after the first transplant. Each of them received 3 infusions, on average 445 000 islet equivalent per transplant. Immunosuppression regimen required multiple adjustments in all patients due to recurrent side effects. In the long-term follow up, kidney function remained stable, and diabetic retinopathy and polyneuropathy did not progress in any of the patients. Patients' panel reactive antibodies remained zero and anti-glutamic acid decarboxylase 65 antibody did not rise after the transplant. Results of metabolic tests including hemoglobin A1c, arginine stimulation, and mixed meal tolerance test were correlated with clinical islet function. CONCLUSIONS: Pancreatic islet transplantation initiated according to Edmonton protocol offered durable long-term insulin-free glycemic control in only highly selected brittle diabetics providing stable control of diabetic neuropathy and retinopathy and without increased sensitization or impaired renal function. Immunosuppression adjustments and close follow-up were critical for patient retention and ultimate success.

19.
Transplantation ; 79(11): 1627-30, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15940055

RESUMO

Standard islet potency testing uses transplantation of islets under the kidney capsule in diabetic severe combined immunodeficient (d-SCID) mice. Even though it is possible to achieve normoglycemia in the majority of recipients by this method, the surgical procedure, by itself, is technically difficult and associated with an appreciable mortality of animals. In addition, the spatially limited renal subcapsular site restricts the mass of islet tissue that can be transplanted. Matrigel basement membrane matrix (MATRIGEL), extracted from a mouse sarcoma, is rich in angiogenic growth factors and has been shown to support the growth of mammalian cells using murine models. In this report we demonstrate that subcutaneous islet transplantation with MATRIGEL can effectively achieve normoglycemia and that this is a simple and reproducible model for in vivo islet potency testing in d-SCID mice that overcomes many drawbacks of the conventional method of kidney subcapsular islet transplantation.


Assuntos
Transplante das Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/citologia , Animais , Glicemia/metabolismo , Colágeno , Combinação de Medicamentos , Transplante das Ilhotas Pancreáticas/métodos , Transplante das Ilhotas Pancreáticas/fisiologia , Laminina , Camundongos , Camundongos SCID , Modelos Animais , Proteoglicanas , Valores de Referência
20.
Lung Cancer ; 47(1): 17-29, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15603851

RESUMO

PURPOSE: Extracellular matrix (ECM) proteins play a significant role in the survival and metastasis of cancer cells. Tenascin-C (TN-C) is an extracellular matrix protein and its large isoform has been implicated in tumor progression. Goal of this study was to analyze the expression of the small and large isoforms of TN-C in non-small cell lung cancer (NSCLC) and determine its functional significance. EXPERIMENTAL DESIGN: TN-C expression was studied in tumor and non-tumor tissue of patients with NSCLC at the mRNA and protein level. Immunomodulatory properties of the large isoform of TN-C were analyzed by determining its effect on lymphocyte proliferation and cytokine secretion by tumor-infiltrating lymphocytes (TIL). RESULTS: Quantitative real-time PCR analysis showed an eight-fold increase in the amount of large isoform in cancer cells compared to adjacent normal tissue. Expression at the protein level by Western blot analysis using a murine monoclonal anti-TN-C antibody detected increased expression of the large isoform in the tumor tissue that was correlated with the development of recurrent disease. A 18-fold increase in the expression of the large TN-C isoform was observed in patients with recurrent NSCLC compared to non-recurrent NSCLC. Large isoform of TN-C significantly inhibited anti-CD3 and mitogen-induced proliferation of human peripheral blood lymphocytes and interferon-gamma production by TIL isolated from the lung cancer specimens. CONCLUSIONS: Increased expression of TN-C observed at the site of tumor in NSCLC correlates with recurrence. TN-C inhibits TIL proliferation and cytokine thereby may promote tumor immune evasion and recurrence.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Linfócitos do Interstício Tumoral/imunologia , Tenascina/biossíntese , Tenascina/farmacologia , Western Blotting , Proliferação de Células , Citocinas/metabolismo , Humanos , Invasividade Neoplásica/imunologia , Recidiva Local de Neoplasia/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
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