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1.
J Behav Med ; 46(6): 1032-1041, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37450207

RESUMO

The premise of this study was to gain more insight into whether type 1 diabetes (T1D) can impact how youth perceive parents and peers. To address limitations of previous observational studies comparing youth with T1D to control youth, propensity weighting was used to mimic a randomized controlled trial. A total of 558 youth with T1D and 426 control youth (14-26y) completed questionnaires on parental responsiveness, psychological control, overprotection, friend support, extreme peer orientation, and a host of background and psychological functioning variables. The groups were statistically weighted to become as comparable as possible except for disease status. The analysis plan and hypotheses were preregistered on the open science framework. Youth with T1D perceived their mothers to be more overprotective, perceived fewer friend support, and were less extremely oriented toward peers than control youth. There were no group differences for paternal overprotection and paternal and maternal responsiveness and psychological control. Mothers of youth with T1D seem at risk to practice overprotective parenting and clinicians could play an important role in making mothers aware of this risk. However, the absence of group differences for the maladaptive parenting dimension of psychological control and adaptive dimension of responsiveness are reassuring and testify to the resilient nature of youth with T1D and their families. Additionally, there is accumulating evidence that T1D could interfere with engaging in supportive friendships.

2.
Am J Transplant ; 22(3): 927-936, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34735732

RESUMO

Intraportal (IP) islet cell transplants can restore metabolic control in type 1 diabetes patients, but limitations raise the need for establishing a functional beta cell mass (FBM) in a confined extrahepatic site. This study reports on function and composition of omental (OM) implants after placement of islet cell grafts with similar beta cell mass as in our IP-protocol (2-5.106 beta cells/kg body weight) on a scaffold. Four of seven C-peptide-negative recipients achieved low beta cell function (hyperglycemic clamp [HGC] 2-8 percent of controls) until laparoscopy, 2-6 months later, for OM-biopsy and concomitant IP-transplant with similar beta cell dose. This IP-transplant increased HGC-values to 15-40 percent. OM-biopsies reflected the composition of initial grafts, exhibiting varying proportions of endocrine-cell-enriched clusters with more beta than alpha cells and leucocyte pole, non-endocrine cytokeratin-positive clusters surrounded by leucocytes, and scaffold remnants with foreign body reaction. OM-implants on a polyglactin-thrombin-fibrinogen-scaffold presented larger endocrine clusters with infiltrating endothelial cells and corresponded to the higher HGC-values. No activation of cellular immunity to GAD/IA2 was measured post-OM-transplant. Establishment of a metabolically adequate FBM in omentum may require a higher beta cell number in grafts but also elimination of their immunogenic non-endocrine components as well as local conditioning that favors endocrine cell engraftment and function.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Diabetes Mellitus Tipo 1/cirurgia , Células Endoteliais , Humanos , Transplante das Ilhotas Pancreáticas/métodos , Omento/cirurgia
3.
Am J Hum Genet ; 104(5): 985-989, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31006513

RESUMO

We report a recurrent CNOT1 de novo missense mutation, GenBank: NM_016284.4; c.1603C>T (p.Arg535Cys), resulting in a syndrome of pancreatic agenesis and abnormal forebrain development in three individuals and a similar phenotype in mice. CNOT1 is a transcriptional repressor that has been suggested as being critical for maintaining embryonic stem cells in a pluripotent state. These findings suggest that CNOT1 plays a critical role in pancreatic and neurological development and describe a novel genetic syndrome of pancreatic agenesis and holoprosencephaly.


Assuntos
Deficiências do Desenvolvimento/etiologia , Holoprosencefalia/etiologia , Doenças do Recém-Nascido/etiologia , Mutação , Doenças do Sistema Nervoso/etiologia , Pâncreas/anormalidades , Pancreatopatias/congênito , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Deficiências do Desenvolvimento/patologia , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/patologia , Feminino , Holoprosencefalia/patologia , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/patologia , Masculino , Camundongos , Camundongos Knockout , Doenças do Sistema Nervoso/patologia , Pâncreas/patologia , Pancreatopatias/etiologia , Pancreatopatias/patologia , Linhagem , Fenótipo , Homologia de Sequência , Síndrome
4.
Lancet ; 397(10291): 2275-2283, 2021 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-34089660

RESUMO

BACKGROUND: People with type 1 diabetes can continuously monitor their glucose levels on demand (intermittently scanned continuous glucose monitoring [isCGM]), or in real time (real-time continuous glucose monitoring [rtCGM]). However, it is unclear whether switching from isCGM to rtCGM with alert functionality offers additional benefits. Therefore, we did a trial comparing rtCGM and isCGM in adults with type 1 diabetes (ALERTT1). METHODS: We did a prospective, double-arm, parallel-group, multicentre, randomised controlled trial in six hospitals in Belgium. Adults with type 1 diabetes who previously used isCGM were randomly assigned (1:1) to rtCGM (intervention) or isCGM (control). Randomisation was done centrally using minimisation dependent on study centre, age, gender, glycated haemoglobin (HbA1c), time in range (sensor glucose 3·9-10·0 mmol/L), insulin administration method, and hypoglycaemia awareness. Participants, investigators, and study teams were not masked to group allocation. Primary endpoint was mean between-group difference in time in range after 6 months assessed in the intention-to-treat sample. This trial is registered with ClinicalTrials.gov, NCT03772600. FINDINGS: Between Jan 29 and Jul 30, 2019, 269 participants were recruited, of whom 254 were randomly assigned to rtCGM (n=127) or isCGM (n=127); 124 and 122 participants completed the study, respectively. After 6 months, time in range was higher with rtCGM than with isCGM (59·6% vs 51·9%; mean difference 6·85 percentage points [95% CI 4·36-9·34]; p<0·0001). After 6 months HbA1c was lower (7·1% vs 7·4%; p<0·0001), as was time <3·0 mmol/L (0·47% vs 0·84%; p=0·0070), and Hypoglycaemia Fear Survey version II worry subscale score (15·4 vs 18·0; p=0·0071). Fewer participants on rtCGM experienced severe hypoglycaemia (n=3 vs n=13; p=0·0082). Skin reaction was more frequently observed with isCGM and bleeding after sensor insertion was more frequently reported by rtCGM users. INTERPRETATION: In an unselected adult type 1 diabetes population, switching from isCGM to rtCGM significantly improved time in range after 6 months of treatment, implying that clinicians should consider rtCGM instead of isCGM to improve the health and quality of life of people with type 1 diabetes. FUNDING: Dexcom.


Assuntos
Automonitorização da Glicemia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemia/diagnóstico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Adulto , Bélgica , Glicemia/análise , Feminino , Hemoglobinas Glicadas/análise , Humanos , Sistemas de Infusão de Insulina , Masculino , Estudos Prospectivos , Qualidade de Vida
5.
Diabetologia ; 64(2): 313-324, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33145642

RESUMO

AIMS/HYPOTHESIS: Numerous clinical studies have investigated the anti-CD3ɛ monoclonal antibody otelixizumab in individuals with type 1 diabetes, but limited progress has been made in identifying the optimal clinical dose with acceptable tolerability and safety. The aim of this study was to evaluate the association between dose-response, safety and tolerability, beta cell function preservation and the immunological effects of otelixizumab in new-onset type 1 diabetes. METHODS: In this randomised, single-blind, placebo-controlled, 24 month study, conducted in five centres in Belgium via the Belgian Diabetes Registry, participants (16-27 years old, <32 days from diagnosis of type 1 diabetes) were scheduled to receive placebo or otelixizumab in one of four dose cohorts (cumulative i.v. dose 9, 18, 27 or 36 mg over 6 days; planned n = 40). Randomisation to treatment was by a central computer system; only participants and bedside study personnel were blinded to study treatment. The co-primary endpoints were the incidence of adverse events, the rate of Epstein-Barr virus (EBV) reactivation, and laboratory measures and vital signs. A mixed-meal tolerance test was used to assess beta cell function; exploratory biomarkers were used to measure T cell responses. RESULTS: Thirty participants were randomised/28 were analysed (placebo, n = 6/5; otelixizumab 9 mg, n = 9/8; otelixizumab 18 mg, n = 8/8; otelixizumab 27 mg, n = 7/7; otelixizumab 36 mg, n = 0). Dosing was stopped at otelixizumab 27 mg as the predefined EBV reactivation stopping criteria were met. Adverse event frequency and severity were dose dependent; all participants on otelixizumab experienced at least one adverse event related to cytokine release syndrome during the dosing period. EBV reactivation (otelixizumab 9 mg, n = 2/9; 18 mg, n = 4/8: 27 mg, n = 5/7) and clinical manifestations (otelixizumab 9 mg, n = 0/9; 18 mg, n = 1/8; 27 mg, n = 3/7) were rapid, dose dependent and transient, and were associated with increased productive T cell clonality that diminished over time. Change from baseline mixed-meal tolerance test C-peptide weighted mean AUC0-120 min following otelixizumab 9 mg was above baseline for up to 18 months (difference from placebo 0.39 [95% CI 0.06, 0.72]; p = 0.023); no beta cell function preservation was observed at otelixizumab 18 and 27 mg. CONCLUSIONS/INTERPRETATION: A metabolic response was observed with otelixizumab 9 mg, while doses higher than 18 mg increased the risk of unwanted clinical EBV reactivation. Although otelixizumab can temporarily compromise immunocompetence, allowing EBV to reactivate, the effect is dose dependent and transient, as evidenced by a rapid emergence of EBV-specific T cells preceding long-term control over EBV reactivation. TRIAL REGISTRATION: ClinicalTrials.gov NCT02000817. FUNDING: The study was funded by GlaxoSmithKline. Graphical abstract.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Adolescente , Adulto , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Progressão da Doença , Relação Dose-Resposta a Droga , Infecções por Vírus Epstein-Barr/induzido quimicamente , Feminino , Humanos , Infecção Latente/induzido quimicamente , Masculino , Método Simples-Cego , Adulto Jovem
6.
Am J Transplant ; 21(6): 2090-2099, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33206461

RESUMO

Detection of amyloid in intraportal islet implants of type 1 diabetes patients has been proposed as cause in their functional decline. The present study uses cultured adult human islets devoid of amyloid to examine conditions of its formation. After intraportal injection in patients, amyloid deposits <15 µm diameter were identified in 5%-12% of beta cell containing aggregates, 3-76 months posttransplant. Such deposits also formed in glucose-controlling islet implants in the kidney of diabetic mice but not in failing implants. Alginate-encapsulated islets formed amyloid during culture when functional, and in all intraperitoneal implants that corrected diabetes in mice, exhibiting larger sizes than in functioning nonencapsulated implants. After intraperitoneal injection in a patient, retrieved single capsules presented amyloid near living beta cells, whereas no amyloid occurred in clustered capsules with dead cells. Amyloid was also demonstrated in functional human stem cell-generated beta cell implants in subcutaneous devices of mice. Deposits up to 35 µm diameter were localized in beta cell-enriched regions and related to an elevated IAPP over insulin ratio in the newly generated beta cells. Amyloid in device-encapsulated human stem cell-generated beta cell implants marks the formation of a functional beta cell mass but also an imbalance between its activated state and its microenvironment.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Adulto , Amiloide , Animais , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Camundongos , Células-Tronco
7.
Transpl Int ; 34(7): 1182-1186, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34048106

RESUMO

Allogeneic islet transplantation is a standard of care treatment for patients with labile type 1 diabetes in many countries around the world, including Japan, the United Kingdom, Australia, much of continental Europe, and parts of Canada. The United States is now endorsing islet cell treatment for type 1 diabetes, but the FDA has chosen to consider islets as a biologic that requires licensure, making the universal implementation of the procedure in the clinic very challenging and opening the manufacture of islet grafts to private companies. The commercialization of human tissues raises significant legal and ethical issues and ironically leads to a situation where treatments developed as a result of the scientific and economic efforts of academia over several decades become exploited exclusively by for-profit entities.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Austrália , Diabetes Mellitus Tipo 1/cirurgia , Europa (Continente) , Humanos , Japão , Reino Unido , Estados Unidos , United States Food and Drug Administration
8.
Diabetologia ; 61(7): 1623-1632, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29679103

RESUMO

AIMS/HYPOTHESIS: HLA-A*24 carriership hampers achievement of insulin independence in islet allograft recipients. However, less than half of those who fail to achieve insulin independence carry the allele. We investigated whether genetic polymorphism at the recipients' zinc transporter 8-encoding SLC30A8 gene (rs13266634) could complement their HLA-A*24 status in predicting functional graft outcome. METHODS: We retrospectively analysed data of a hospital-based patient cohort followed for 18 months post transplantation. Forty C-peptide-negative type 1 diabetic individuals who received >2 million beta cells (>4000 islet equivalents) per kg body weight in one or two intraportal implantations under similar immunosuppression were genotyped for SLC30A8. Outcome measurements included achievement and maintenance of graft function. Metabolic benefit was defined as <25% CV of fasting glycaemia in the presence of >331 pmol/l C-peptide, in addition to achievement of insulin independence and maintenance of C-peptide positivity. RESULTS: In multivariate analysis, HLA-A*24 positivity, presence of SLC30A8 CT or TT genotypes and BMI more than or equal to the group median (23.9 kg/m2) were independently associated with failure to achieve insulin independence (p = 0.015-0.046). The risk increased with the number of factors present (p < 0.001). High BMI interacted with SLC30A8 T allele carriership to independently predict difficulty in achieving graft function with metabolic benefit (p = 0.015). Maintenance of C-peptide positivity was mainly associated with older age at the time of implantation. Only HLA-A*24 carriership independently predicted failure to maintain acceptable graft function once achieved (p = 0.012). CONCLUSIONS/INTERPRETATION: HLA-A*24, the SLC30A8 T allele and high BMI are associated with poor graft outcome and should be considered in the interpretation of future transplantation trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT00798785 and NCT00623610.


Assuntos
Glicemia/metabolismo , Índice de Massa Corporal , Diabetes Mellitus Tipo 1/cirurgia , Antígeno HLA-A24/genética , Células Secretoras de Insulina/transplante , Transplante das Ilhotas Pancreáticas/efeitos adversos , Polimorfismo Genético , Transportador 8 de Zinco/genética , Aloenxertos , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Feminino , Antígeno HLA-A24/imunologia , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
9.
BMC Med Genet ; 18(1): 57, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28525974

RESUMO

BACKGROUND: Pancreatic agenesis is an extremely rare cause of neonatal diabetes mellitus and has enabled the discovery of several key transcription factors essential for normal pancreas and beta cell development. CASE PRESENTATION: We report a case of a Caucasian female with complete pancreatic agenesis occurring together with semilobar holoprosencephaly (HPE), a more common brain developmental disorder. Clinical findings were later confirmed by autopsy, which also identified agenesis of the gallbladder. Although the sequences of a selected set of genes related to pancreas agenesis or HPE were wild-type, the patient's phenotype suggests a genetic defect that emerges early in embryonic development of brain, gallbladder and pancreas. CONCLUSIONS: Developmental defects of the pancreas and brain can occur together. Identifying the genetic defect may identify a novel key regulator in beta cell development.


Assuntos
Anormalidades Congênitas/genética , Vesícula Biliar/anormalidades , Holoprosencefalia/genética , Pâncreas/anormalidades , Encéfalo/anormalidades , Encéfalo/embriologia , Anormalidades Congênitas/diagnóstico , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Feminino , Vesícula Biliar/embriologia , Holoprosencefalia/diagnóstico , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/genética , Pâncreas/embriologia , Análise de Sequência de DNA , População Branca
10.
J Immunol ; 189(8): 3947-56, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22988034

RESUMO

CD4(+)Foxp3(+) regulatory T cells (Treg) are essential for immune homeostasis and maintenance of self-tolerance. They are produced in the thymus and also generated de novo in the periphery in a TGF-ß-dependent manner. Foxp3(+) Treg are also required to achieve tolerance to transplanted tissues when induced by coreceptor or costimulation blockade. Using TCR-transgenic mice to avoid issues of autoimmune pathology, we show that Foxp3 expression is both necessary and sufficient for tissue tolerance by coreceptor blockade. Moreover, the known need in tolerance induction for TGF-ß signaling to T cells can wholly be explained by its role in induction of Foxp3, as such signaling proved dispensable for the suppressive process. We analyzed the relative contribution of TGF-ß and Foxp3 to the transcriptome of TGF-ß-induced Treg and showed that TGF-ß elicited a large set of downregulated signature genes. The number of genes uniquely modulated due to the influence of Foxp3 alone was surprisingly limited. Retroviral-mediated conditional nuclear expression of Foxp3 proved sufficient to confer transplant-suppressive potency on CD4(+) T cells and was lost once nuclear Foxp3 expression was extinguished. These data support a dual role for TGF-ß and Foxp3 in induced tolerance, in which TGF-ß stimulates Foxp3 expression, for which sustained expression is then associated with acquisition of tolerance.


Assuntos
Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/genética , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante , Animais , Linhagem Celular Tumoral , Fatores de Transcrição Forkhead/deficiência , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/fisiologia , Tolerância ao Transplante/genética
11.
Lancet Diabetes Endocrinol ; 11(2): 96-108, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702566

RESUMO

BACKGROUND: Comparing Continuous With Flash Glucose Monitoring In Adults With Type 1 Diabetes (ALERTT1) examined whether switching from first-generation intermittently scanned continuous glucose monitoring (isCGM) without alerts to real-time continuous glucose monitoring (rtCGM) with alert functionality offers additional benefits to adults with type 1 diabetes. The extension of the randomised ALERTT1 trial assessed the effect of switching from isCGM to rtCGM up to 24 months. METHODS: In this 6-month, double-arm, parallel-group, non-masked, randomised, controlled trial, done across six hospitals in Belgium, 254 adults aged 18 years or older with type 1 diabetes previously using isCGM were randomly assigned (1:1) to rtCGM with alerts (intervention; n=127) or isCGM without alerts (control; n=127). Upon completion of the 6-month trial, the control group switched to rtCGM (is-rtCGM group), and the intervention group continued rtCGM (rt-rtCGM group). The extension focused on within-group changes in time in range (TIR; 3·9-10·0 mmol/L; primary outcome), HbA1c, time in clinically significant hypoglycaemia (<3·0 mmol/L), and Hypoglycaemia Fear Survey worry (HFS-worry) score (all prespecified key secondary outcomes). Mean within-group change versus the start of rtCGM is reported, with a positive value referring to a lower value at start of rtCGM. This trial is registered at ClinicalTrials.gov (NCT03772600). FINDINGS: 119 participants were assigned to the is-rtCGM group of whom 112 (94%) completed the 24-month trial, and 123 participants were assigned to the rt-rtCGM group of whom 117 (95%) completed the 24-month trial. TIR increased from 51·8% (95% CI 49·1-54·5) at start of rtCGM (month 6) to 63·5% (60·7-66·3) at month 12 in the is-rtCGM group, and remained stable up to month 24 (change 11·7 percentage points [pp] [9·4-14·0; p<0·0001). In the rt-rtCGM group, TIR increased from 52·5% (95% CI 49·8-55·1) at start of rtCGM (month 0) to 63·0% (60·3-65·8) at month 12, also remaining stable up to month 24 (change 10·5 pp [8·2-12·8]; p<0·0001). HbA1c decreased from 7·4% (57 mmol/mol; month 6) to 6·9% (52 mmol/mol) at month 24 (change -0·54 pp [95% CI -0·64 to -0·44]; -5 mmol/mol [95% CI -6 to -4]; p<0·0001) in the is-rtCGM group, and from 7·4% (57 mmol/mol; month 0) to 7·0% (53 mmol/mol) at month 24 (change -0·43 pp [95% CI -0·53 to -0·33]; -4 mmol/mol [95% CI -5 to -3]; p<0·0001) in the rt-rtCGM group. The change in HFS-worry score was -2·67 (month 24 vs month 6; p=0·0008) in the is-rtCGM group and -5·17 points (month 24 vs month 0; p<0·0001) in the rt-rtCGM group. Time in clinically significant hypoglycaemia was unchanged in both groups after month 12. Severe hypoglycaemia decreased from 31·0 to 3·3 per 100 patient-years after switching to rtCGM. INTERPRETATION: Glycaemic control and hypoglycaemia worry improved significantly up to 24 months after switching from isCGM without alerts to rtCGM with alerts, supporting the use of rtCGM in the care of adults with type 1 diabetes. FUNDING: Dexcom.


Assuntos
Diabetes Mellitus Tipo 1 , Hipoglicemia , Humanos , Adulto , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Automonitorização da Glicemia/métodos , Glicemia , Hipoglicemia/prevenção & controle
12.
Cell Transplant ; 31: 9636897221096160, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35583214

RESUMO

Patients fulfilling criteria for euthanasia can choose to donate their organs after circulatory death [donors after euthanasia (DCD V)]. This study assesses the outcome of islet cell isolation from DCD V pancreases. A procedure for DCD V procurement provided 13 pancreases preserved in Institut Georges Lopez-1 preservation solution and following acirculatory warm ischemia time under 10 minutes. Islet cell isolation outcomes are compared with those from reference donors after brain death (DBD, n = 234) and a cohort of donors after controlled circulatory death (DCD III, n = 29) procured under the same conditions. Islet cell isolation from DCD V organs resulted in better in vitro outcome than for selected DCD III or reference DBD organs. A 50% higher average beta cell number before and after culture and a higher average beta cell purity (35% vs 24% and 25%) was observed, which led to more frequent selection for our clinical protocol (77% of isolates vs 50%). The functional capacity of a DCD V islet cell preparation was illustrated by its in vivo effect following intraportal transplantation in a type 1 diabetes patient: injection of 2 million beta cells/kg body weight (1,900 IEQ/kg body weight) at 39% insulin purity resulted in an implant with functional beta cell mass that represented 30% of that in non-diabetic controls. In conclusion, this study describes procurement and preservation conditions for donor organs after euthanasia, which allow preparation of cultured islet cells, that more frequently meet criteria for clinical use than those from DBD or DCD III organs.


Assuntos
Células Secretoras de Insulina , Doadores de Tecidos , Peso Corporal , Morte Encefálica , Eutanásia , Humanos , Células Secretoras de Insulina/transplante , Pâncreas
13.
J Diabetes Sci Technol ; : 19322968221128315, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36172693

RESUMO

BACKGROUND: ALERTT1 showed that switching from intermittently scanned continuous glucose monitoring (isCGM) without alerts to real-time CGM (rtCGM) with alert functionality improved time in range (TIR; 70-180 mg/dL), glycated hemoglobin (HbA1c), time <54 mg/dL, and Hypoglycemia Fear Survey version II worry subscale (HFS-worry) score after six months in adults with type 1 diabetes (T1D). Moderator analyses aimed to identify certain subgroups that would benefit more from switching to rtCGM than others. METHODS: Post hoc analyses of ALERTT1 evaluated the impact of 14 baseline characteristics on the difference (delta) in mean TIR, HbA1c, time <54 mg/dL, and HFS-worry score at six months between rtCGM and isCGM. Therefore, the delta was allowed to depend on each of these variables by including interactions in the moderator analysis model. Analyses were performed separately for each variable; variables with P < .10 in the univariable analysis were combined into a single model. RESULTS: Univariable analyses showed no dependency of delta TIR, HbA1c, or time <54 mg/dL on variables other than CGM type. Only delta HFS-worry score depended on baseline HbA1c (P = .0059), indicating less worries with rtCGM in people with baseline HbA1c <6.5% or ≥8%. Given P < .10 for dependency of delta TIR on insulin therapy type (favoring multiple daily injections), baseline HbA1c, and baseline TIR, these variables were combined into a multivariable analysis; interactions were not statistically significant. CONCLUSIONS: Except for HFS-worry score, no interactions between 14 baseline characteristics and the six-month intervention effect of rtCGM on TIR, HbA1c, or time <54 mg/dL were observed, supporting the conclusion of ALERTT1 that switching from isCGM without alerts to rtCGM with alert functionality is beneficial for a wide range of people with T1D.

14.
J Autoimmun ; 37(3): 151-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21636247

RESUMO

Autoreactive cytotoxic CD8 T-cells (CTLs) play a key pathogenic role in the destruction of insulin-producing beta-cells resulting in type 1 diabetes. However, knowledge regarding their targets is limited, restricting the ability to monitor the course of the disease and immune interventions. In a multi-step discovery process to identify novel CTL epitopes in human preproinsulin (PPI), PPI was digested with purified human proteasomes, and resulting COOH-fragments aligned with algorithm-predicted HLA-binding peptides to yield nine potential HLA-A1, -A2, -A3 or -B7-restricted candidates. An UV-exchange method allowed the generation of a repertoire of multimers including low-affinity HLA-binding peptides. These were labeled with quantum dot-fluorochromes and encoded in a combinatorial fashion, allowing parallel and sensitive detection of specific, low-avidity T-cells. Significantly increased frequencies of T-cells against four novel PPI epitopes (PPI(4-13)/B7, PPI(29-38)/A2, PPI(76-84)/A3 and PPI(79-88)/A3) were detected in stored blood of patients with recent onset diabetes but not in controls. Changes in frequencies of circulating CD8 T-cells against these novel epitopes were detected in blood of islet graft recipients at different time points after transplantation, which correlated with clinical outcome. In conclusion, our novel strategy involving a sensitive multiplex detection technology and requiring minimal volumes of stored blood represents a major improvement in the direct ex-vivo characterization and enumeration of immune cells in the pathogenesis of type 1 diabetes.


Assuntos
Autoimunidade , Linfócitos T CD8-Positivos/metabolismo , Técnicas de Química Combinatória , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/metabolismo , Insulina/química , Peptídeos/química , Precursores de Proteínas/química , Algoritmos , Sequência de Aminoácidos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Epitopos , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/metabolismo , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/metabolismo , Antígenos HLA-A/química , Antígenos HLA-A/imunologia , Antígenos HLA-A/metabolismo , Antígeno HLA-B7/química , Antígeno HLA-B7/imunologia , Antígeno HLA-B7/metabolismo , Humanos , Insulina/imunologia , Insulina/metabolismo , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/patologia , Células Secretoras de Insulina/transplante , Transplante das Ilhotas Pancreáticas/imunologia , Complexo Principal de Histocompatibilidade , Dados de Sequência Molecular , Peptídeos/análise , Peptídeos/imunologia , Peptídeos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Precursores de Proteínas/imunologia , Precursores de Proteínas/metabolismo , Pontos Quânticos
15.
Diabetes Metab Res Rev ; 27(8): 925-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22069286

RESUMO

BACKGROUND: The safety of any immune modulating agent in type 1 diabetes mellitus (T1DM) involves its selectivity on autoimmunity and its preservation of recall and tumour immunity. METHODS: We performed lymphocyte proliferation tests on seven recent onset diabetic patients treated with anti-CD3 (Otelixizumab; ChAglyCD3) and five recent onset diabetic patients treated with placebo, on average 2 years after therapy. RESULTS: Proliferative responses towards common viral, bacterial and yeast antigens upon in vitro stimulation with a range of recall antigens in anti-CD3-treated T1DM patients were highly similar to those in placebo-treated T1DM patients. Similarly, T-cell responses towards autoantigens were equally low between the two groups, several years after diagnosis of T1DM. The proliferative response upon stimulation with the human suppressor protein p53 was invariably high in both anti-CD3- and placebo-treated patients, implying preserved anti-tumour immunity in anti-CD3 treatment. CONCLUSIONS: As long-term focus on side effects is key, we demonstrate in this sub-cohort of recent onset T1DM patients treated with Otelixizumab that recall immunity is preserved in spite of high-dose anti-CD3 treatment, adding to the safety of anti-CD3 treatment as an immune-modulatory agent in the treatment of T1DM.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Complexo CD3/imunologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Memória Imunológica/fisiologia , Humanos , Tolerância Imunológica/imunologia
16.
Front Pediatr ; 9: 624416, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33614555

RESUMO

Background and Aims: The management of chronic inflammatory bowel diseases in youth is challenging. We aimed to determine health literacy (HL), quality of life (QoL) and clinical outcomes in young adults from the BELgian CROhn's disease registry (BELCRO) in comparison to type 1 diabetes mellitus (DM) as a control. Methods: In this prospective and observational study, young adults with Crohn's disease (CD) diagnosed < 18 years and with > 5 years disease duration and a comparable group of patients with DM completed validated HL, QoL and work productivity and activity impairment questionnaires (HLS-EU-Q16, EQ-5D-5L and WPAI). HL was scored as sufficient (13-16), problematic (9-12) or inadequate (0-8). QoL was dichotomized into "no problems" (EQ-5D level 1) or "problems" (EQ-5D levels 2 to 5). Non-parametric (Mann-Whitney U) analyses and Spearman correlations were performed. Results: A total of 52 CD (median [IQR] age of 25.0 [23.8-27.0], 64% male) and 50 DM (age 20.0 [19.0-22.0], 50% male) patients were included. HL was 14.0 [11.0-16.0] for CD and 14.0 [11.3-14.8] for DM (p = 0.6) with similar proportions of sufficient (60 vs. 68%, p = 0.4), problematic (34 vs. 26%, p = 0.3) and inadequate HL (both 6%, p = 1). Although QoL was comparable for CD and DM (77.0 [68.8-82.0] vs. 75.0 [65.0-80.0] %, p =0.4), CD had a trend for higher pain/discomfort (50 vs. 32%, p = 0.06). HL and QoL correlated in CD (r = 0.6, p < 0.001) and DM patients (r = 0.6, p < 0.001). Fewer CD patients with recent hospitalization/surgery had sufficient HL (31 vs. 69%, p = 0.01) and had lower QoL (70.0 [60.0-77.0] vs. 80.0 [70.0-85.0], p = 0.04) compared to those without. Conclusions: Selected young Belgian adults suffering from CD for >5 years have similar and sufficient HL compared to DM patients. However, CD patients requiring hospitalization/surgery have lower HL, which indicates the need for targeted educational programs.

17.
Transplantation ; 104(10): e295-e302, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32433237

RESUMO

BACKGROUND: Clinical islet transplantation is generally conducted within 72 hours after isolating sufficient beta-cell mass. A preparation that does not meet the sufficient dose can be cultured until this is reached after combination with subsequent ones. This retrospective study examines whether metabolic outcome is influenced by culture duration. METHODS: Forty type 1 diabetes recipients of intraportal islet cell grafts under antithymocyte globulin induction and mycophenolate mofetil-tacrolimus maintenance immunosuppression were analyzed. One subgroup (n = 10) was transplanted with preparations cultured for ≥96 hours; in the other subgroup (n = 30) grafts contained similar beta-cell numbers but included isolates that were cultured for a shorter duration. Both subgroups were compared by numbers with plasma C-peptide ≥0.5 ng/mL, low glycemic variability associated with C-peptide ≥1.0 ng/mL, and with insulin independence. RESULTS: The subgroup with all cells cultured ≥96 hours exhibited longer C-peptide ≥0.5 ng/mL (103 versus 48 mo; P = 0.006), and more patients with low glycemic variability and C-peptide ≥1.0 ng/mL, at month 12 (9/10 versus 12/30; P = 0.005) and 24 (7/10 versus 6/30; P = 0.007). In addition, 9/10 became insulin-independent versus 15/30 (P = 0.03). Grafts with all cells cultured ≥96 hours did not contain more beta cells but a higher endocrine purity (49% versus 36%; P = 0.03). In multivariate analysis, longer culture duration and older recipient age were independently associated with longer graft function. CONCLUSIONS: Human islet isolates with insufficient beta-cell mass for implantation within 72 hours can be cultured for 96 hours and longer to combine multiple preparations in order to reach the desired beta-cell dose and therefore result in a better metabolic benefit.


Assuntos
Proliferação de Células , Diabetes Mellitus Tipo 1/cirurgia , Células Secretoras de Insulina/transplante , Transplante das Ilhotas Pancreáticas , Adulto , Biomarcadores/sangue , Glicemia/metabolismo , Peptídeo C/sangue , Células Cultivadas , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Técnicas de Cultura de Tecidos , Resultado do Tratamento
18.
Transplantation ; 101(9): 2218-2227, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27779572

RESUMO

BACKGROUND: Induction therapy with a T cell-depleting agent followed by mycophenolate mofetil and tacrolimus is presently the most frequently used immune suppression (IS) regimen in islet transplantation. This study assesses its safety and tolerability in nonuremic type 1 diabetic recipients. METHODS: Fifty-one patients (age, between 29 and 63 years) with high glycemic variability and problematic hypoglycemia received intraportal islet grafts under anti-thymocyte globulin-mycophenolate mofetil-tacrolimus protocol. They were followed up for over 48 months for function of the implant and adverse events. RESULTS: Severe hypoglycemia and diabetic ketoacidosis were absent in patients with functioning graft. Immune suppressive therapy was maintained for 48 months in 29 recipients with sustained function (group A), whereas 16 patients stopped earlier due to graft failure (group B) and in 6 for other reasons. Group A was significantly older at the time of implantation and achieved higher graft function at posttransplantation month 6 under similar dose of IS. Prevalence of IS-related side effects was similar in groups A and B, occurring predominantly during the first year posttransplantation. IS-related serious adverse events (SAE) were reported in 47% of patients, with 4 presenting with cytomegalovirus infection and 4 (age, 42-59 years) diagnosed with cancer. Except in 1 patient with cancer, all SAEs resolved after appropriate treatment. CONCLUSIONS: These risk/benefit data serve as a basis for clinical decision-making before entering an intraportal islet transplantation protocol. A longer benefit is observed in recipients of higher age (≥40 years), but it is not associated with more side effects and SAE.


Assuntos
Soro Antilinfocitário/uso terapêutico , Diabetes Mellitus Tipo 1/cirurgia , Imunossupressores/uso terapêutico , Transplante das Ilhotas Pancreáticas , Ácido Micofenólico/uso terapêutico , Tacrolimo/uso terapêutico , Adulto , Soro Antilinfocitário/efeitos adversos , Biomarcadores/sangue , Glicemia/metabolismo , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/sangue , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/efeitos adversos , Transplante das Ilhotas Pancreáticas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/efeitos adversos , Complicações Pós-Operatórias/etiologia , Medição de Risco , Fatores de Risco , Tacrolimo/efeitos adversos , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento
19.
Front Immunol ; 7: 124, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27148253

RESUMO

Regulatory T cells expressing the transcription factor Foxp3 require acquisition of a specific hypomethylation pattern to ensure optimal functional commitment, limited lineage plasticity, and long-term maintenance of tolerance. A better understanding of the molecular mechanisms involved in the generation of these epigenetic changes in vivo will contribute to the clinical exploitation of Foxp3(+) Treg. Here, we show that both in vitro and in vivo generated antigen-specific Foxp3(+) Treg can acquire Treg-specific epigenetic characteristics and prevent skin graft rejection in an animal model.

20.
Diabetes Care ; 39(6): 1060-4, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27208324

RESUMO

OBJECTIVE: We investigated whether changes in islet autoantibody profile and presence of HLA risk markers, reported to predict rapid ß-cell loss in pre-type 1 diabetes, associate with poor functional outcome in islet allograft recipients. RESEARCH DESIGN AND METHODS: Forty-one patients received ≥2.3 million ß-cells/kg body wt in one to two intraportal implantations. Outcome after 6-18 months was assessed by C-peptide (random and stimulated), insulin dose, and HbA1c. RESULTS: Patients carrying HLA-A*24-positive or experiencing a significant autoantibody surge within 6 months after the first transplantation (n = 19) had lower C-peptide levels (P ≤ 0.003) and higher insulin needs (P < 0.001) despite higher HbA1c levels (P ≤ 0.018). They became less often insulin independent (16% vs. 68%, P = 0.002) and remained less often C-peptide positive (47% vs. 100%, P < 0.001) than recipients lacking both risk factors. HLA-A*24 positivity or an autoantibody surge predicted insulin dependence (P = 0.007). CONCLUSIONS: HLA-A*24 and early autoantibody surge after islet implantation associate with poor functional graft outcome.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/terapia , Antígeno HLA-A24/genética , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Transplante das Ilhotas Pancreáticas , Adulto , Aloenxertos , Peptídeo C/metabolismo , Proteínas de Transporte de Cátions/imunologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Feminino , Glutamato Descarboxilase/imunologia , Humanos , Células Secretoras de Insulina , Masculino , Pessoa de Meia-Idade , Transplante Homólogo , Resultado do Tratamento , Transportador 8 de Zinco
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