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1.
Mol Metab ; 76: 101772, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37442376

RESUMO

OBJECTIVES: Readily accessible human pancreatic beta cells that are functionally close to primary adult beta cells are a crucial model to better understand human beta cell physiology and develop new treatments for diabetes. We here report the characterization of EndoC-ßH5 cells, the latest in the EndoC-ßH cell family. METHODS: EndoC-ßH5 cells were generated by integrative gene transfer of immortalizing transgenes hTERT and SV40 large T along with Herpes Simplex Virus-1 thymidine kinase into human fetal pancreas. Immortalizing transgenes were removed after amplification using CRE activation and remaining non-excized cells eliminated using ganciclovir. Resulting cells were distributed as ready to use EndoC-ßH5 cells. We performed transcriptome, immunological and extensive functional assays. RESULTS: Ready to use EndoC-ßH5 cells display highly efficient glucose dependent insulin secretion. A robust 10-fold insulin secretion index was observed and reproduced in four independent laboratories across Europe. EndoC-ßH5 cells secrete insulin in a dynamic manner in response to glucose and secretion is further potentiated by GIP and GLP-1 analogs. RNA-seq confirmed abundant expression of beta cell transcription factors and functional markers, including incretin receptors. Cytokines induce a gene expression signature of inflammatory pathways and antigen processing and presentation. Finally, modified HLA-A2 expressing EndoC-ßH5 cells elicit specific A2-alloreactive CD8 T cell activation. CONCLUSIONS: EndoC-ßH5 cells represent a unique storable and ready to use human pancreatic beta cell model with highly robust and reproducible features. Such cells are thus relevant for the study of beta cell function, screening and validation of new drugs, and development of disease models.


Assuntos
Células Secretoras de Insulina , Humanos , Células Secretoras de Insulina/metabolismo , Secreção de Insulina , Linhagem Celular , Insulina/metabolismo , Fatores de Transcrição/metabolismo , Glucose/metabolismo
9.
Anat Rec (Hoboken) ; 300(8): 1429-1438, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28296236

RESUMO

Our objectives were to describe, in Beagle dogs, the ontogenesis of beta (insulin-producing) and alpha (glucagon-producing) cells from fetal to early postnatal life and adulthood. In addition, to have some insight into interspecies comparison, Beagle dog pancreases were compared to pancreases from a Labrador and Chow Chow. At midgestation, the epithelium was dense, beta cells scarce, and alpha cells numerous and concentrated in the center of the pancreatic bud. From 36 to 45 days post conception (pc), beta cell numbers increased and the epithelium expanded and branched out. At 55 days pc, large beta cell aggregates were seen. At weaning, the islets were similar to those in adults, with limited alpha cells intermingled with numerous beta cells. Quantification of the Alpha to Beta cells ratio has shown a gradual increase of beta cells proportion throughout development. Similar findings were obtained in the two other breeds. In conclusion, in the fetal Beagle dog beta cells emerge from the pancreatic bud at midgestation, but the endocrine structure is mature only in early postnatal life. The ontogenesis of the endocrine pancreas demonstrated in dogs resembles that reported in rats and mice. In contrast, human beta cells appear earlier, at the beginning of the second trimester of gestation. Our study provides a detailed morphological description of pancreatic development in dogs but supplies no information on alpha- or beta-cell function during fetal life. The morphological data reported here provide a foundation for building physiological studies. Anat Rec, 300:1429-1438, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Feto/citologia , Regulação da Expressão Gênica no Desenvolvimento , Ilhotas Pancreáticas/crescimento & desenvolvimento , Animais , Cães , Feminino , Feto/metabolismo , Glucagon/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Gravidez
10.
Cell Med ; 8(3): 99-112, 2016 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-28003935

RESUMO

Innovative treatments to cure type 1 diabetes are being actively researched. Among the different strategies, the replacement of ß-cells has given promising results. Classically, islets from cadaveric donors are transplanted into diabetic patients, but recently phase I clinical trials that use stem cell-derived ß-cells have been started. Such protocols require either an immunosuppressive treatment or the macroencapsulation of the ß-cells. They involve cell aggregation and the exposure of the cells to hypoxia. Using an engineered human ß-cell, we have addressed these two problems: a novel human ß-cell line called EndoC-ßH3 was cultured as single cells or aggregated clusters. EndoC-ßH3 cells were also cultured at normal atmospheric oxygen tension (pO2 = 21%) or hypoxia (pO2 = 3%) in the presence or absence of modulators of the hypoxia-inducible factor 1α (HIF1α) pathway. Cell aggregation improved glucose-stimulated insulin secretion, demonstrating the benefit of cell-cell contacts. Low oxygen tension decreased ß-cell viability and their sensitivity to glucose, but did not alter insulin production nor the insulin secretion capacity of the remaining cells. To investigate the role of HIF1α, we first used a HIF stabilizer at pO2 = 21%. This led to a mild decrease in cell viability, impaired glucose sensitivity, and altered insulin secretion. Finally, we used a HIF inhibitor on EndoC-ßH3 pseudoislets exposed to hypoxia. Such treatment considerably decreased cell viability. In conclusion, aggregation of the EndoC-ßH3 cells seems to be important to improve their function. A fraction of the EndoC-ßH3 cells are resistant to hypoxia, depending on the level of activity of HIF1α. Thus, these cells represent a good human cell model for future investigations on islet cell transplantation analysis.

11.
Acta Diabetol ; 53(3): 413-21, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26467464

RESUMO

AIMS: To address questions regarding onset and progression of types 1 and 2 diabetes (T1D/T2D), surrogate imaging biomarkers for beta cell function and mass are needed. Here, we assess the potential of GPR44 as a surrogate marker for beta cells, in a direct comparison with clinically used biomarker VMAT2. METHODS: GPR44 surface availability was assessed by flow cytometry of human beta cells. RNA transcription levels in different pancreas compartments were evaluated. The density of GPR44 receptor in endocrine and exocrine tissues was assessed by the radiolabeled GPR44 ligand [(3)H]AZD 3825. A direct comparison with the established beta cell marker VMAT2 was performed by radiolabeled [(3)H]DTBZ. RESULTS: GPR44 was available on the cell surface, and pancreatic RNA levels were restricted to the islets of Langerhans. [(3)H]AZD 3825 had nanomolar affinity for GPR44 in human islets and EndoC-ßH1 beta cells, and the specific binding to human beta cells was close to 50 times higher than in exocrine preparations. The endocrine-to-exocrine binding ratio was approximately 10 times higher for [(3)H]AZD 3825 than for [(3)H]DTBZ. CONCLUSION: GPR44 is a highly beta cell-specific target, which potentially offers improved imaging contrast between the human beta cell and the exocrine pancreas.


Assuntos
Diabetes Mellitus/metabolismo , Células Secretoras de Insulina/metabolismo , Receptores Imunológicos/metabolismo , Receptores de Prostaglandina/metabolismo , Animais , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Células HEK293 , Humanos , Especificidade de Órgãos , Ratos , Receptores Imunológicos/genética , Receptores de Prostaglandina/genética , Proteínas Vesiculares de Transporte de Monoamina/genética , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
12.
Diabetologia ; 59(1): 170-175, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26489735

RESUMO

AIMS/HYPOTHESIS: Genetically engineered human beta cell lines provide a novel source of human beta cells to study metabolism, pharmacology and beta cell replacement therapy. Since the immune system is essentially involved in beta cell destruction in type 1 diabetes and after beta cell transplantation, we investigated the interaction of human beta cell lineswith the immune system to resolve their potential for immune intervention protocol studies. METHODS: Human pancreatic beta cell lines (EndoC-ßH1 and ECi50) generated by targeted oncogenesis in fetal pancreas were assessed for viability after innate and adaptive immune challenges. Beta cell lines were pre-conditioned with T helper type 1 (Th1) cytokines or high glucose to mimic inflammatory and hyperglycaemia-stressed conditions. Beta cells were then co-cultured with auto- and alloreactive cytotoxic T cells (CTL), natural killer (NK) cells, supernatant fraction from activated autoreactive Th1 cells, or alloantibodies in the presence of complement or effector cells. RESULTS: Low HLA expression protected human beta cell lines from adaptive immune destruction, but it was associated with direct killing by activated NK cells. Autoreactive Th1 cell inflammation, rather than glucose stress, induced increased beta cell apoptosis and upregulation of HLA, increasing beta cell vulnerability to killing by auto- and alloreactive CTL and alloreactive antibodies. CONCLUSIONS/INTERPRETATION: We demonstrate that genetically engineered human beta cell lines can be used in vitro to assess diverse immune responses that may be involved in the pathogenesis of type 1 diabetes in humans and beta cell transplantation, enabling preclinical evaluation of novel immune intervention strategies protecting beta cells from immune destruction.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Células Secretoras de Insulina/imunologia , Anticorpos/imunologia , Linhagem Celular , Transplante de Células/métodos , Proteínas do Sistema Complemento/imunologia , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Engenharia Genética/métodos , Genótipo , Antígenos HLA/imunologia , Células HeLa , Humanos , Hiperglicemia/metabolismo , Sistema Imunitário , Inflamação , Células Secretoras de Insulina/citologia , Células Matadoras Naturais/citologia , Leucócitos Mononucleares/citologia , Linfócitos T Citotóxicos/citologia , Células Th1/citologia
13.
Horm Res Paediatr ; 83(2): 102-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25634148

RESUMO

BACKGROUND/OBJECTIVE: Normally sited glands account for increasing congenital hypothyroidism (CH). Mechanisms often remain unknown. To report the incidence of CH with in situ thyroid gland (ISTG) and describe the natural history of the disease without known etiology. METHOD: Clinical, biochemical and imaging data at diagnosis were retrospectively analyzed in 285 children positively screened for CH in Ile-de-France between 2005 and 2008. If treatment was discontinued, management of hormonal substitution and follow-up of biochemical thyroid function was performed. RESULTS: 93 full-term CH neonates displayed ISTG (40.6%), including 50 with unexplained mechanism. Follow-up data were available in 32 of them. Therapy was withdrawn from 20 children at a median age of 23.5 months (6-66), among whom 18 remained still untreated over a median duration of 15.3 months (4.4-29.6). In 11 children, levothyroxine (L-T4) dosage was increased over time to maintain biochemical euthyroidism. No statistical differences in initial TSH or FT4 levels, iodine status or birth weight were found between children with transient and permanent hypothyroidism. CONCLUSION: Withdrawal of L-T4 substitution was feasible in 56.2% of full-term children with CH with ISTG but unexplained mechanism, emphasizing the need for systematic therapy withdrawal. However, further studies are warranted to standardize withdrawal protocol.


Assuntos
Hipotireoidismo Congênito/tratamento farmacológico , Terapia de Reposição Hormonal , Glândula Tireoide/metabolismo , Tiroxina/uso terapêutico , Criança , Pré-Escolar , Hipotireoidismo Congênito/sangue , Hipotireoidismo Congênito/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Lactente , Masculino , Estudos Retrospectivos , Tireotropina/sangue , Tiroxina/sangue
14.
Mol Metab ; 4(12): 916-25, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26909308

RESUMO

OBJECTIVES: Access to immortalized human pancreatic beta cell lines that are phenotypically close to genuine adult beta cells, represent a major tool to better understand human beta cell physiology and develop new therapeutics for Diabetes. Here we derived a new conditionally immortalized human beta cell line, EndoC-ßH3 in which immortalizing transgene can be efficiently removed by simple addition of tamoxifen. METHODS: We used lentiviral mediated gene transfer to stably integrate a tamoxifen inducible form of CRE (CRE-ERT2) into the recently developed conditionally immortalized EndoC ßH2 line. The resulting EndoC-ßH3 line was characterized before and after tamoxifen treatment for cell proliferation, insulin content and insulin secretion. RESULTS: We showed that EndoC-ßH3 expressing CRE-ERT2 can be massively amplified in culture. We established an optimized tamoxifen treatment to efficiently excise the immortalizing transgenes resulting in proliferation arrest. In addition, insulin expression raised by 12 fold and insulin content increased by 23 fold reaching 2 µg of insulin per million cells. Such massive increase was accompanied by enhanced insulin secretion upon glucose stimulation. We further observed that tamoxifen treated cells maintained a stable function for 5 weeks in culture. CONCLUSIONS: EndoC ßH3 cell line represents a powerful tool that allows, using a simple and efficient procedure, the massive production of functional non-proliferative human beta cells. Such cells are close to genuine human beta cells and maintain a stable phenotype for 5 weeks in culture.

15.
J Clin Invest ; 124(5): 2087-98, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24667639

RESUMO

Diabetic patients exhibit a reduction in ß cells, which secrete insulin to help regulate glucose homeostasis; however, little is known about the factors that regulate proliferation of these cells in human pancreas. Access to primary human ß cells is limited and a challenge for both functional studies and drug discovery progress. We previously reported the generation of a human ß cell line (EndoC-ßH1) that was generated from human fetal pancreas by targeted oncogenesis followed by in vivo cell differentiation in mice. EndoC-ßH1 cells display many functional properties of adult ß cells, including expression of ß cell markers and insulin secretion following glucose stimulation; however, unlike primary ß cells, EndoC-ßH1 cells continuously proliferate. Here, we devised a strategy to generate conditionally immortalized human ß cell lines based on Cre-mediated excision of the immortalizing transgenes. The resulting cell line (EndoC-ßH2) could be massively amplified in vitro. After expansion, transgenes were efficiently excised upon Cre expression, leading to an arrest of cell proliferation and pronounced enhancement of ß cell-specific features such as insulin expression, content, and secretion. Our data indicate that excised EndoC-ßH2 cells are highly representative of human ß cells and should be a valuable tool for further analysis of human ß cells.


Assuntos
Linhagem Celular Transformada/citologia , Proliferação de Células , Células Secretoras de Insulina/citologia , Animais , Linhagem Celular Transformada/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Insulina/biossíntese , Células Secretoras de Insulina/metabolismo , Camundongos
17.
Acta Paediatr ; 102(8): 787-96, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23586744

RESUMO

UNLABELLED: Normal growth is a sign of good health. Monitoring for growth disturbances is fundamental to children's health care. Early detection and diagnosis of the causes of short stature allows management of underlying medical conditions, optimizing attainment of good health and normal adult height. CONCLUSION: This review summarizes currently available information on monitoring for short stature in children and conditions usually associated with short stature and summarizes the authors' conclusions on the early recognition of growth disorders.


Assuntos
Proteção da Criança , Diagnóstico Precoce , Intervenção Médica Precoce/métodos , Transtornos do Crescimento/diagnóstico , Transtornos do Crescimento/terapia , Adolescente , Adulto , Fatores Etários , Estatura , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Monitorização Fisiológica/métodos , Prognóstico , Medição de Risco , Fatores Sexuais , Fatores de Tempo
18.
J Clin Endocrinol Metab ; 98(7): 2746-54, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23626006

RESUMO

CONTEXT: Recombinant human GH (rhGH) improves growth and body composition in glucocorticoid-treated children. Its effects on muscle strength are poorly evaluated. OBJECTIVES: Our objective was to evaluate rhGH effects on muscle strength in children receiving long-term glucocorticoid therapy; effects on height SD score (SDS) and body composition were assessed also. DESIGN AND SETTING: A randomized, controlled, delayed-start study of rhGH for 12 months was started after randomization (baseline) or 6 months later (M6). PATIENTS: Patients included 30 children with various diagnoses. INTERVENTION: rhGH was administered at 0.065 mg/kg/d for 6 months and then in the dosage maintaining serum IGF-I levels below +2 SDS for chronological age. MAIN OUTCOME MEASURES: The primary criterion was the between-group difference in composite index of muscle strength (CIMS) change at M6. Secondary criteria included between-group differences in CIMS SDS(height), lean mass (LM), thigh muscle area (MA), and height SDS changes at M6; these parameters were also assessed in the overall population after 1 year of rhGH therapy. RESULTS: At M6, rhGH therapy did not significantly affect changes in CIMS or CIMS SDS(height) (+17.6% vs +7.5% and +0.14 ± 0.38 vs +0.11 ± 0.62, respectively); the rhGH-treated group had significantly larger changes in height SDS (+0.2 [0.3] vs -0.2 [0.3]; P = 0.003), LM (+7.3% [+3.7%; +21.6%] vs 0% [-4.7%; +3.2%]; P = 0.002), and MA (+8.8% [+5%; +15.6%] vs. -0.6% [-6.3%; +7.7%]; P = 0.01) compared with the untreated group. After 1 year of rhGH, height SDS, LM, and MA increased significantly, CIMS increased by 24.7% (+5.8%; +34.2%), and CIMS SDS(height) remained within the normal range. CONCLUSIONS: rhGH increased height, LM, and MA. However, muscle strength did not improve significantly.


Assuntos
Desenvolvimento do Adolescente/efeitos dos fármacos , Composição Corporal/efeitos dos fármacos , Desenvolvimento Infantil/efeitos dos fármacos , Doença Crônica/tratamento farmacológico , Glucocorticoides/efeitos adversos , Hormônio do Crescimento Humano/uso terapêutico , Força Muscular/efeitos dos fármacos , Adolescente , Estatura/efeitos dos fármacos , Criança , Monitoramento de Medicamentos , Feminino , Seguimentos , Glucocorticoides/uso terapêutico , Transtornos do Crescimento/induzido quimicamente , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/prevenção & controle , Hormônio do Crescimento Humano/administração & dosagem , Hormônio do Crescimento Humano/efeitos adversos , Humanos , Fator de Crescimento Insulin-Like I/análise , Masculino , Debilidade Muscular/etiologia , Debilidade Muscular/prevenção & controle , Projetos Piloto , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico
20.
Lancet Diabetes Endocrinol ; 1(3): 199-207, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24622368

RESUMO

BACKGROUND: Neonatal diabetes mellitus is a rare genetic form of pancreatic ß-cell dysfunction. We compared phenotypic features and clinical outcomes according to genetic subtypes in a cohort of patients diagnosed with neonatal diabetes mellitus before age 1 year, without ß-cell autoimmunity and with normal pancreas morphology. METHODS: We prospectively investigated patients from 20 countries referred to the French Neonatal Diabetes Mellitus Study Group from 1995 to 2010. Patients with hyperglycaemia requiring treatment with insulin before age 1 year were eligible, provided that they had normal pancreatic morphology as assessed by ultrasonography and negative tests for ß-cell autoimmunity. We assessed changes in the 6q24 locus, KATP-channel subunit genes (ABCC8 and KCNJ11), and preproinsulin gene (INS) and investigated associations between genotype and phenotype, with special attention to extra-pancreatic abnormalities. FINDINGS: We tested 174 index patients, of whom 47 (27%) had no detectable genetic defect. Of the remaining 127 index patients, 40 (31%) had 6q24 abnormalities, 43 (34%) had mutations in KCNJ11, 31 (24%) had mutations in ABCC8, and 13 (10%) had mutations in INS. We reported developmental delay with or without epilepsy in 13 index patients (18% of participants with mutations in genes encoding KATP channel subunits). In-depth neuropsychomotor investigations were done at median age 7 years (IQR 1-15) in 27 index patients with mutations in KATP channel subunit genes who did not have developmental delay or epilepsy. Developmental coordination disorder (particularly visual-spatial dyspraxia) or attention deficits were recorded in all index patients who had this testing. Compared with index patients who had mutations in KATP channel subunit genes, those with 6q24 abnormalities had specific features: developmental defects involving the heart, kidneys, or urinary tract (8/36 [22%] vs 2/71 [3%]; p=0·002), intrauterine growth restriction (34/37 [92%] vs 34/70 [48%]; p<0·0001), and early diagnosis (median age 5·0 days, IQR 1·0-14·5 vs 45·5 days, IQR 27·2-95·0; p<0·0001). Remission of neonatal diabetes mellitus occurred in 89 (51%) index patients at a median age of 17 weeks (IQR 9·5-39·0; median follow-up 4·7 years, IQR 1·5-12·8). Recurrence was common, with no difference between the groups who had 6q24 abnormalities versus mutations in KATP channel subunit genes (82% vs 86%; p=0·36). INTERPRETATION: Neonatal diabetes mellitus is often associated with neuropsychological dysfunction and developmental defects that are specific to the underlying genetic abnormality. A multidisciplinary assessment is therefore essential when patients are diagnosed. Features of neuropsychological dysfunction and developmental defects should be tested for in adults with a history of neonatal diabetes mellitus. FUNDING: Agence Nationale de la Recherche-Maladies Rares Research Program Grant, the Transnational European Research Grant on Rare Diseases, the Société Francophone du Diabète-Association Française du Diabète, the Association Française du Diabète, Aide aux Jeunes Diabétiques, a CIFRE grant from the French Government, HRA-Pharma, the French Ministry of Education and Research, and the Société Française de Pédiatrie.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 6/genética , Deficiências do Desenvolvimento/genética , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Fenótipo , Transtornos Psicomotores/genética , Criança , Estudos de Coortes , Deficiências do Desenvolvimento/patologia , França/epidemiologia , Estudos de Associação Genética , Humanos , Lactente , Recém-Nascido , Insulina/genética , Estimativa de Kaplan-Meier , Mutação/genética , Pâncreas/diagnóstico por imagem , Canais de Potássio Corretores do Fluxo de Internalização/genética , Estudos Prospectivos , Precursores de Proteínas/genética , Transtornos Psicomotores/patologia , Receptores de Sulfonilureias/genética , Ultrassonografia
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