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1.
Diabetologia ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38910151

RESUMO

Given the proven benefits of screening to reduce diabetic ketoacidosis (DKA) likelihood at the time of stage 3 type 1 diabetes diagnosis, and emerging availability of therapy to delay disease progression, type 1 diabetes screening programmes are being increasingly emphasised. Once broadly implemented, screening initiatives will identify significant numbers of islet autoantibody-positive (IAb+) children and adults who are at risk of (confirmed single IAb+) or living with (multiple IAb+) early-stage (stage 1 and stage 2) type 1 diabetes. These individuals will need monitoring for disease progression; much of this care will happen in non-specialised settings. To inform this monitoring, JDRF in conjunction with international experts and societies developed consensus guidance. Broad advice from this guidance includes the following: (1) partnerships should be fostered between endocrinologists and primary-care providers to care for people who are IAb+; (2) when people who are IAb+ are initially identified there is a need for confirmation using a second sample; (3) single IAb+ individuals are at lower risk of progression than multiple IAb+ individuals; (4) individuals with early-stage type 1 diabetes should have periodic medical monitoring, including regular assessments of glucose levels, regular education about symptoms of diabetes and DKA, and psychosocial support; (5) interested people with stage 2 type 1 diabetes should be offered trial participation or approved therapies; and (6) all health professionals involved in monitoring and care of individuals with type 1 diabetes have a responsibility to provide education. The guidance also emphasises significant unmet needs for further research on early-stage type 1 diabetes to increase the rigour of future recommendations and inform clinical care.

2.
S D Med ; 76(suppl 6): s23-s24, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37732925

RESUMO

INTRODUCTION: Over the last 13 years, the Immune Tolerance Network (ITN), has conducted trials of agents to abrogate the autoimmunity underlying type 1 diabetes. Primary endpoints center on the change of C-peptide production during mixed meal tolerance tests (MMTT), measured as the area under the curve (AUC) or AUC mean over 2-3 years. Studies permit rapid-acting insulin until a few hours before the MMTT, and thus do not exclude overnight hyperglycemia prior to testing. We hypothesize that overnight or fasting hyperglycemia will deplete pre-formed insulin and impact measurements of first-phase insulin secretion and C-peptide AUC. METHODS: Publicly available, deidentified, subject-level data were obtained from ITN TrialShare. We developed several graphical analyses to reexamine results from each MMTT including combined glucose and C-peptide response curves, the centroids of polygons of MMTT timepoints, and ratios comparing extents of excursions of glucose and c-peptide production. RESULTS: We have applied these graphical analyses to 1161 MMTT from 245 subjects in 8 studies. Graphical analyses of MMTT results for individuals over the course of the follow-up period reflect the expected loss of c-peptide and higher blood glucose during MMTT; centroids move accordingly, upwards and leftwards. CONCLUSIONS: We were able to analyze MMTT data from ITN studies with several graphical analyses. We are poised to apply these approaches to test our central hypothesis by comparing how deviations from modeled rates of predicted changes for an individual over time correlate with blood glucose levels in the hours before a MMTT. This may lead to refinement of future trial protocols to ensure tighter regulation of glycemic excursions ahead of provocative testing.


Assuntos
Diabetes Mellitus Tipo 1 , Hiperglicemia , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Glicemia , Peptídeo C , Glucose , Hiperglicemia/diagnóstico
3.
Cell Immunol ; 358: 104224, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33068914

RESUMO

Type 1 Diabetes (T1D) is an autoimmune disease marked by direct elimination of insulin-producing ß cells by autoreactive T effectors. Recent T1D clinical trials utilizing autologous Tregs transfers to restore immune balance and improve disease has prompted us to design a novel Tregs-based antigen-specific T1D immunotherapy. We engineered a Chimeric Antigen Receptor (CAR) expressing a single-chain Fv recognizing the human pancreatic endocrine marker, HPi2. Human T cells, transduced with the resultant HPi2-CAR, proliferated and amplified Granzyme B accumulation when co-cultured with human, but not mouse ß cells. Furthermore, following exposure of HPi2-CAR transduced cells to islets, CD8+ lymphocytes demonstrated enhanced CD107a (LAMP-1) expression, while CD4+ cells produced increased levels of IL-2. HPi2-CAR Tregs failed to maintain expansion due to a persistent tonic signaling from the CAR engagement to unexpectantly HPi2 antigen present on Tregs. Overall, we show lack of functionality of HPi2-CAR and highlight the importance of careful selection of CAR recognition driver for the sustainable activity and expandability of engineered T cells.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Protaminas/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular , Humanos , Tolerância Imunológica/imunologia , Imunoterapia Adotiva/métodos , Ilhotas Pancreáticas , Pâncreas/citologia , Pâncreas/metabolismo , Protaminas/metabolismo , Engenharia de Proteínas/métodos , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/metabolismo
4.
Infect Immun ; 84(10): 3007-16, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27481239

RESUMO

The CPS1 gene was identified as a virulence factor in the maize pathogen Cochliobolus heterostrophus Hypothesizing that the homologous gene in Coccidioides posadasii could be important for virulence, we created a Δcps1 deletion mutant which was unable to cause disease in three strains of mice (C57BL/6, BALB/c, or the severely immunodeficient NOD-scid,γc(null) [NSG]). Only a single colony was recovered from 1 of 60 C57BL/6 mice following intranasal infections of up to 4,400 spores. Following administration of very high doses (10,000 to 2.5 × 10(7) spores) to NSG and BALB/c mice, spherules were observed in lung sections at time points from day 3 to day 10 postinfection, but nearly all appeared degraded with infrequent endosporulation. Although the role of CPS1 in virulence is not understood, phenotypic alterations and transcription differences of at least 33 genes in the Δcps1 strain versus C. posadasii is consistent with both metabolic and regulatory functions for the gene. The in vitro phenotype of the Δcps1 strain showed slower growth of mycelia with delayed and lower spore production than C. posadasii, and in vitro spherules were smaller. Vaccination of C57BL/6 or BALB/c mice with live Δcps1 spores either intranasally, intraperitoneally, or subcutaneously resulted in over 95% survival with mean residual lung fungal burdens of <1,000 CFU from an otherwise lethal C. posadasii intranasal infection. Considering its apparently complete attenuation of virulence and the high degree of resistance to C. posadasii infection when used as a vaccine, the Δcps1 strain is a promising vaccine candidate for preventing coccidioidomycosis in humans or other animals.


Assuntos
Coccidioides/fisiologia , Coccidioidomicose/genética , Deleção de Sequência , Fatores de Virulência/genética , Virulência/fisiologia , Animais , Coccidioides/genética , Coccidioidomicose/prevenção & controle , Modelos Animais de Doenças , Feminino , Proteínas Fúngicas/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Vacinação/métodos
5.
Nat Genet ; 38(7): 794-800, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16767104

RESUMO

Phosphodiesterases (PDEs) regulate cyclic nucleotide levels. Increased cyclic AMP (cAMP) signaling has been associated with PRKAR1A or GNAS mutations and leads to adrenocortical tumors and Cushing syndrome. We investigated the genetic source of Cushing syndrome in individuals with adrenocortical hyperplasia that was not caused by known defects. We performed genome-wide SNP genotyping, including the adrenocortical tumor DNA. The region with the highest probability to harbor a susceptibility gene by loss of heterozygosity (LOH) and other analyses was 2q31-2q35. We identified mutations disrupting the expression of the PDE11A isoform-4 gene (PDE11A) in three kindreds. Tumor tissues showed 2q31-2q35 LOH, decreased protein expression and high cyclic nucleotide levels and cAMP-responsive element binding protein (CREB) phosphorylation. PDE11A codes for a dual-specificity PDE that is expressed in adrenal cortex and is partially inhibited by tadalafil and other PDE inhibitors; its germline inactivation is associated with adrenocortical hyperplasia, suggesting another means by which dysregulation of cAMP signaling causes endocrine tumors.


Assuntos
Glândulas Suprarrenais/enzimologia , Glândulas Suprarrenais/patologia , Mutação , Diester Fosfórico Hidrolases/genética , 3',5'-GMP Cíclico Fosfodiesterases , Adulto , Criança , Cromossomos Humanos Par 2/genética , Síndrome de Cushing/enzimologia , Síndrome de Cushing/genética , Síndrome de Cushing/patologia , Feminino , Humanos , Hiperplasia , Perda de Heterozigosidade , Masculino , Diester Fosfórico Hidrolases/metabolismo , Polimorfismo de Nucleotídeo Único
6.
Sci Transl Med ; 16(746): eadn2404, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38718135

RESUMO

CD4+CD25hiCD127lo/-FOXP3+ regulatory T cells (Tregs) play a key role in preventing autoimmunity. In autoimmune type 1 diabetes (T1D), adoptive transfer of autologous polyclonal Tregs has been shown to be safe in adults in phase 1 clinical trials. We explored factors contributing to efficacy of autologous polyclonal expanded Tregs (expTregs) in a randomized phase 2 multi-center, double-blind, clinical trial (Sanford/Lisata Therapeutics T-Rex phase 2 trial, ClinicalTrials.gov NCT02691247). One hundred ten treated children and adolescents with new-onset T1D were randomized 1:1:1 to high-dose (20 × 106 cells/kilogram) or low-dose (1 × 106 cells/kilogram) treatments or to matching placebo. Cytometry as well as bulk and single-cell RNA sequencing were performed on selected expTregs and peripheral blood samples from participants. The single doses of expTregs were safe but did not prevent decline in residual ß cell function over 1 year compared to placebo (P = 0.94 low dose, P = 0.21 high dose), regardless of age or baseline C-peptide. ExpTregs were highly activated and suppressive in vitro. A transient increase of activated memory Tregs was detectable 1 week after infusion in the high-dose cohort, suggesting effective transfer of expTregs. However, the in vitro fold expansion of expTregs varied across participants, even when accounting for age, and lower fold expansion and its associated gene signature were linked with better C-peptide preservation regardless of Treg dose. These results suggest that a single dose of polyclonal expTregs does not alter progression in T1D; instead, Treg quality may be an important factor.


Assuntos
Diabetes Mellitus Tipo 1 , Linfócitos T Reguladores , Humanos , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/terapia , Linfócitos T Reguladores/imunologia , Criança , Adolescente , Masculino , Feminino , Método Duplo-Cego , Pré-Escolar , Transplante Autólogo
7.
Horm Res Paediatr ; : 1-12, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38663372

RESUMO

Teplizumab (TzieldTM, Provention Bio), a monoclonal antibody directed at T-cell marker CD3, is the first medication approved by the FDA to delay progression from stage 2 to stage 3 type 1 diabetes. To date, the overwhelming majority of pediatric endocrinologists do not have experience using immunotherapeutics and seek guidance on the use of teplizumab in clinical practice. To address this need, the Pediatric Endocrine Society (PES) Diabetes Special Interest Group (Diabetes SIG) and Drug and Therapeutics Committee assembled a task force to review clinical trial data and solicit expert recommendations on the approach to teplizumab infusions. We present considerations on all aspects of teplizumab administration, utilizing evidence where possible and providing a spectrum of expert opinions on unknown aspects. We discuss patient selection and prescreening, highlighting the safety and considerations for monitoring and treatment of side effects. We propose a schedule of events, a protocol for administration, and discuss practice management aspects. We advocate for the need for further long-term systematic surveillance studies to continue evaluating the efficacy and safety of teplizumab.

8.
Commun Med (Lond) ; 4(1): 66, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582818

RESUMO

BACKGROUND: Islet autoantibodies form the foundation for type 1 diabetes (T1D) diagnosis and staging, but heterogeneity exists in T1D development and presentation. We hypothesized that autoantibodies can identify heterogeneity before, at, and after T1D diagnosis, and in response to disease-modifying therapies. METHODS: We systematically reviewed PubMed and EMBASE databases (6/14/2022) assessing 10 years of original research examining relationships between autoantibodies and heterogeneity before, at, after diagnosis, and in response to disease-modifying therapies in individuals at-risk or within 1 year of T1D diagnosis. A critical appraisal checklist tool for cohort studies was modified and used for risk of bias assessment. RESULTS: Here we show that 152 studies that met extraction criteria most commonly characterized heterogeneity before diagnosis (91/152). Autoantibody type/target was most frequently examined, followed by autoantibody number. Recurring themes included correlations of autoantibody number, type, and titers with progression, differing phenotypes based on order of autoantibody seroconversion, and interactions with age and genetics. Only 44% specifically described autoantibody assay standardization program participation. CONCLUSIONS: Current evidence most strongly supports the application of autoantibody features to more precisely define T1D before diagnosis. Our findings support continued use of pre-clinical staging paradigms based on autoantibody number and suggest that additional autoantibody features, particularly in relation to age and genetic risk, could offer more precise stratification. To improve reproducibility and applicability of autoantibody-based precision medicine in T1D, we propose a methods checklist for islet autoantibody-based manuscripts which includes use of precision medicine MeSH terms and participation in autoantibody standardization workshops.


Islet autoantibodies are markers found in the blood when insulin-producing cells in the pancreas become damaged and can be used to predict future development of type 1 diabetes. We evaluated published literature to determine whether characteristics of islet antibodies (type, levels, numbers) could improve prediction and help understand differences in how individuals with type 1 diabetes respond to treatments. We found existing evidence shows that islet autoantibody type and number are most useful to predict disease progression before diagnosis. In addition, the age when islet autoantibodies first appear strongly influences rate of progression. These findings provide important information for patients and care providers on how islet autoantibodies can be used to understand future type 1 diabetes development and to identify individuals who have the potential to benefit from intervention or prevention therapy.

9.
Diabetes Care ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912694

RESUMO

Given the proven benefits of screening to reduce diabetic ketoacidosis (DKA) likelihood at the time of stage 3 type 1 diabetes diagnosis, and emerging availability of therapy to delay disease progression, type 1 diabetes screening programs are being increasingly emphasized. Once broadly implemented, screening initiatives will identify significant numbers of islet autoantibody-positive (IAb+) children and adults who are at risk for (confirmed single IAb+) or living with (multiple IAb+) early-stage (stage 1 and stage 2) type 1 diabetes. These individuals will need monitoring for disease progression; much of this care will happen in nonspecialized settings. To inform this monitoring, JDRF, in conjunction with international experts and societies, developed consensus guidance. Broad advice from this guidance includes the following: 1) partnerships should be fostered between endocrinologists and primary care providers to care for people who are IAb+; 2) when people who are IAb+ are initially identified, there is a need for confirmation using a second sample; 3) single IAb+ individuals are at lower risk of progression than multiple IAb+ individuals; 4) individuals with early-stage type 1 diabetes should have periodic medical monitoring, including regular assessments of glucose levels, regular education about symptoms of diabetes and DKA, and psychosocial support; 5) interested people with stage 2 type 1 diabetes should be offered trial participation or approved therapies; and 6) all health professionals involved in monitoring and care of individuals with type 1 diabetes have a responsibility to provide education. The guidance also emphasizes significant unmet needs for further research on early-stage type 1 diabetes to increase the rigor of future recommendations and inform clinical care.

10.
Commun Med (Lond) ; 3(1): 130, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37794169

RESUMO

BACKGROUND: Type 1 diabetes (T1D) results from immune-mediated destruction of insulin-producing beta cells. Prevention efforts have focused on immune modulation and supporting beta cell health before or around diagnosis; however, heterogeneity in disease progression and therapy response has limited translation to clinical practice, highlighting the need for precision medicine approaches to T1D disease modification. METHODS: To understand the state of knowledge in this area, we performed a systematic review of randomized-controlled trials with ≥50 participants cataloged in PubMed or Embase from the past 25 years testing T1D disease-modifying therapies and/or identifying features linked to treatment response, analyzing bias using a Cochrane-risk-of-bias instrument. RESULTS: We identify and summarize 75 manuscripts, 15 describing 11 prevention trials for individuals with increased risk for T1D, and 60 describing treatments aimed at preventing beta cell loss at disease onset. Seventeen interventions, mostly immunotherapies, show benefit compared to placebo (only two prior to T1D onset). Fifty-seven studies employ precision analyses to assess features linked to treatment response. Age, beta cell function measures, and immune phenotypes are most frequently tested. However, analyses are typically not prespecified, with inconsistent methods of reporting, and tend to report positive findings. CONCLUSIONS: While the quality of prevention and intervention trials is overall high, the low quality of precision analyses makes it difficult to draw meaningful conclusions that inform clinical practice. To facilitate precision medicine approaches to T1D prevention, considerations for future precision studies include the incorporation of uniform outcome measures, reproducible biomarkers, and prespecified, fully powered precision analyses into future trial design.


Type 1 diabetes (T1D) is a condition that results from the destruction of a type of cell in the pancreas that produces the hormone insulin, leading to lifelong dependence on insulin injections. T1D prevention remains a challenging goal, largely due to the immense variability in disease processes and progression. Therapies tested to date in medical research settings (clinical trials) work only in a subset of individuals, highlighting the need for more tailored prevention approaches. We reviewed clinical trials of therapies targeting the disease process in T1D. While the overall quality of trials was high, studies testing individual features affecting responses to treatments were low. This review reveals an important need to carefully plan high-quality analyses of features that affect treatment response in T1D, to ensure that tailored approaches may one day be applied to clinical practice.

11.
medRxiv ; 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37131690

RESUMO

Background: Type 1 diabetes (T1D) results from immune-mediated destruction of insulin-producing beta cells. Efforts to prevent T1D have focused on modulating immune responses and supporting beta cell health; however, heterogeneity in disease progression and responses to therapies have made these efforts difficult to translate to clinical practice, highlighting the need for precision medicine approaches to T1D prevention. Methods: To understand the current state of knowledge regarding precision approaches to T1D prevention, we performed a systematic review of randomized-controlled trials from the past 25 years testing disease-modifying therapies in T1D and/or identifying features linked to treatment response, analyzing bias using a Cochrane-risk-of-bias instrument. Results: We identified 75 manuscripts, 15 describing 11 prevention trials for individuals with increased risk for T1D, and 60 describing treatments aimed at preventing beta cell loss in individuals at disease onset. Seventeen agents tested, mostly immunotherapies, showed benefit compared to placebo (only two prior to T1D onset). Fifty-seven studies employed precision analyses to assess features linked to treatment response. Age, measures of beta cell function and immune phenotypes were most frequently tested. However, analyses were typically not prespecified, with inconsistent methods reporting, and tended to report positive findings. Conclusions: While the quality of prevention and intervention trials was overall high, low quality of precision analyses made it difficult to draw meaningful conclusions that inform clinical practice. Thus, prespecified precision analyses should be incorporated into the design of future studies and reported in full to facilitate precision medicine approaches to T1D prevention. Plain Language Summary: Type 1 diabetes (T1D) results from the destruction of insulin-producing cells in the pancreas, necessitating lifelong insulin dependence. T1D prevention remains an elusive goal, largely due to immense variability in disease progression. Agents tested to date in clinical trials work in a subset of individuals, highlighting the need for precision medicine approaches to prevention. We systematically reviewed clinical trials of disease-modifying therapy in T1D. While age, measures of beta cell function, and immune phenotypes were most commonly identified as factors that influenced treatment response, the overall quality of these studies was low. This review reveals an important need to proactively design clinical trials with well-defined analyses to ensure that results can be interpreted and applied to clinical practice.

12.
Diabetes Technol Ther ; 25(1): 1-12, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36472543

RESUMO

Objective: To evaluate safety and effectiveness of MiniMed™ 670G hybrid closed loop (HCL) in comparison with continuous subcutaneous insulin infusion (CSII) therapy for 6 months in persons with type 1 diabetes (T1D). Methods: Adults (aged 18-80 years), adolescents, and children (aged 2-17 years) with T1D who were using CSII therapy were enrolled and randomized (1:1) to 6 months of HCL intervention (n = 151, mean age of 39.9 ± 19.8 years) or CSII without continuous glucose monitoring (n = 151, 35.7 ± 18.4 years). Primary effectiveness endpoints included change in A1C for Group 1 (baseline A1C >8.0%), from baseline to the end of study, and difference in the end of study percentage of time spent below 70 mg/dL (%TBR <70 mg/dL) for Group 2 (baseline A1C ≤8.0%), to show superiority of HCL intervention versus control. Secondary effectiveness endpoints were change in A1C and %TBR <70 mg/dL for Group 2 and Group 1, respectively, to show noninferiority of HCL intervention versus control. Primary safety endpoints were rates of severe hypoglycemia and diabetic ketoacidosis (DKA). Results: Change in A1C and difference in %TBR <70 mg/dL for the overall group were significantly improved, in favor of HCL intervention. In addition, a significant mean (95% confidence interval) change in A1C was observed for both Group 1 (-0.8% [-1.1% to -0.4%], P < 0.0001) and Group 2 (-0.3% [-0.5% to -0.1%], P < 0.0001), in favor of HCL intervention. The same was observed for difference in %TBR <70 mg/dL for Group 1 (-2.2% [-3.6% to -0.9%]) and Group 2 (-4.9% [-6.3% to -3.6%]) (P < 0.0001 for both). There was one DKA event during run-in and six severe hypoglycemic events: two during run-in and four during study (HCL: n = 0 and CSII: n = 4 [6.08 per 100 patient-years]). Conclusions: This RCT demonstrates that the MiniMed 670G HCL safely and significantly improved A1C and %TBR <70 mg/dL compared with CSII control in persons with T1D, irrespective of baseline A1C level.


Assuntos
Diabetes Mellitus Tipo 1 , Cetoacidose Diabética , Adolescente , Adulto , Criança , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Glicemia , Automonitorização da Glicemia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Cetoacidose Diabética/tratamento farmacológico , Hemoglobinas Glicadas , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Sistemas de Infusão de Insulina , Pré-Escolar , Idoso , Idoso de 80 Anos ou mais
13.
Hum Mol Genet ; 19(8): 1387-98, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20080939

RESUMO

PRKAR1A inactivation leads to dysregulated cAMP signaling and Carney complex (CNC) in humans, a syndrome associated with skin, endocrine and other tumors. The CNC phenotype is not easily explained by the ubiquitous cAMP signaling defect; furthermore, Prkar1a(+/-) mice did not develop skin and other CNC tumors. To identify whether a Prkar1a defect is truly a generic but weak tumorigenic signal that depends on tissue-specific or other factors, we investigated Prkar1a(+/-) mice when bred within the Rb1(+/-) or Trp53(+/-) backgrounds, or treated with a two-step skin carcinogenesis protocol. Prkar1a(+/-) Trp53(+/-) mice developed more sarcomas than Trp53(+/-) mice (P < 0.05) and Prkar1a(+/-) Rb1(+/-) mice grew more (and larger) pituitary and thyroid tumors than Rb1(+/-) mice. All mice with double heterozygosity had significantly reduced life-spans compared with their single-heterozygous counterparts. Prkar1a(+/-) mice also developed more papillomas than wild-type animals. A whole-genome transcriptome profiling of tumors produced by all three models identified Wnt signaling as the main pathway activated by abnormal cAMP signaling, along with cell cycle abnormalities; all changes were confirmed by qRT-PCR array and immunohistochemistry. siRNA down-regulation of Ctnnb1, E2f1 or Cdk4 inhibited proliferation of human adrenal cells bearing a PRKAR1A-inactivating mutation and Prkar1a(+/-) mouse embryonic fibroblasts and arrested both cell lines at the G0/G1 phase of the cell cycle. In conclusion, Prkar1a haploinsufficiency is a relatively weak tumorigenic signal that can act synergistically with other tumor suppressor gene defects or chemicals to induce tumors, mostly through Wnt-signaling activation and cell cycle dysregulation, consistent with studies in human neoplasms carrying PRKAR1A defects.


Assuntos
Ciclo Celular , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Neoplasias/genética , Neoplasias/patologia , Proteína do Retinoblastoma/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteínas Wnt/metabolismo , Animais , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Haploidia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Processos Neoplásicos , Papiloma/induzido quimicamente , Papiloma/genética , Papiloma/metabolismo , Papiloma/fisiopatologia , Proteína do Retinoblastoma/metabolismo , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/fisiopatologia , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt/genética
14.
Diabetes ; 71(4): 610-623, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35316839

RESUMO

Most screening programs to identify individuals at risk for type 1 diabetes have targeted relatives of people living with the disease to improve yield and feasibility. However, ∼90% of those who develop type 1 diabetes do not have a family history. Recent successes in disease-modifying therapies to impact the course of early-stage disease have ignited the consideration of the need for and feasibility of population screening to identify those at increased risk. Existing population screening programs rely on genetic or autoantibody screening, and these have yielded significant information about disease progression and approaches for timing for screening in clinical practice. At the March 2021 Type 1 Diabetes TrialNet Steering Committee meeting, a session was held in which ongoing efforts for screening in the general population were discussed. This report reviews the background of these efforts and the details of those programs. Additionally, we present hurdles that need to be addressed for successful implementation of population screening and provide initial recommendations for individuals with positive screens so that standardized guidelines for monitoring and follow-up can be established.


Assuntos
Diabetes Mellitus Tipo 1 , Autoanticorpos , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/epidemiologia , Humanos , Programas de Rastreamento
15.
JCI Insight ; 6(21)2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34747368

RESUMO

BackgroundIL-6 receptor (IL-6R) signaling drives development of T cell populations important to type 1 diabetes pathogenesis. We evaluated whether blockade of IL-6R with monoclonal antibody tocilizumab would slow loss of residual ß cell function in newly diagnosed type 1 diabetes patients.MethodsWe conducted a multicenter, randomized, placebo-controlled, double-blind trial with tocilizumab in new-onset type 1 diabetes. Participants were screened within 100 days of diagnosis. Eligible participants were randomized 2:1 to receive 7 monthly doses of tocilizumab or placebo. The primary outcome was the change from screening in the mean AUC of C-peptide collected during the first 2 hours of a mixed meal tolerance test at week 52 in pediatric participants (ages 6-17 years).ResultsThere was no statistical difference in the primary outcome between tocilizumab and placebo. Immunophenotyping showed reductions in downstream signaling of the IL-6R in T cells but no changes in CD4 memory subsets, Th17 cells, Tregs, or CD4+ T effector cell resistance to Treg suppression. A DC subset decreased during therapy but regressed to baseline once therapy stopped. Tocilizumab was well tolerated.ConclusionTocilizumab reduced T cell IL-6R signaling but did not modulate CD4+ T cell phenotypes or slow loss of residual ß cell function in newly diagnosed individuals with type 1 diabetes.Trial RegistrationClinicalTrials.gov NCT02293837.FundingNIH National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and National Institute of Allergy and Infectious Diseases (NIAID) UM1AI109565, UL1TR000004 from NIH/National Center for Research Resources (NCRR) Clinical and Translational Science Award (CTSA), NIH/NIDDK P30DK036836, NIH/NIDDK U01DK103266, NIH/NIDDK U01DK103266, 1UL1TR000064 from NIH/NCRR CTSA, NIH/National Center for Advancing Translational Sciences (NCATS) UL1TR001878, UL1TR002537 from NIH/CTSA; National Health and Medical Research Council Practitioner Fellowship (APP1136735), NIH/NIDDK U01-DK085476, NIH/CTSA UL1-TR002494, Indiana Clinical and Translational Science Institute Award UL1TR002529, Vanderbilt Institute for Clinical and Translational Research UL1TR000445. NIH/NCATS UL1TR003142, NIH/CTSA program UL1-TR002494, Veteran Affairs Administration, and 1R01AI132774.


Assuntos
Subpopulações de Linfócitos B/metabolismo , Diabetes Mellitus Tipo 1/genética , Receptores de Interleucina-6/antagonistas & inibidores , Adolescente , Criança , Diabetes Mellitus Tipo 1/patologia , Método Duplo-Cego , Feminino , Humanos , Masculino
16.
Cancer Res ; 66(24): 11571-5, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17178847

RESUMO

Several types of adrenocortical tumors that lead to Cushing syndrome may be caused by aberrant cyclic AMP (cAMP) signaling. We recently identified patients with micronodular adrenocortical hyperplasia who were carriers of inactivating mutations in the 2q-located phosphodiesterase 11A (PDE11A) gene. We now studied the frequency of two missense substitutions, R804H and R867G, in conserved regions of the enzyme in several sets of normal controls, including 745 individuals enrolled in a longitudinal cohort study, the New York Cancer Project. In the latter, we also screened for the presence of the previously identified PDE11A nonsense mutations. R804H and R867G were frequent among patients with adrenocortical tumors; although statistical significance was not reached, these variants affected significantly enzymatic function in vitro with variable increases in cAMP and/or cyclic guanosine 3',5'-monophosphate levels in HeLa and HEK293 cells. Adrenocortical tissues carrying the R804H mutation showed 2q allelic losses and higher cyclic nucleotide levels and cAMP-responsive element binding protein phosphorylation. We conclude that missense mutations of the PDE11A gene that affect enzymatic activity in vitro are present in the general population; protein-truncating PDE11A mutations may also contribute to a predisposition to other tumors, in addition to their association with adrenocortical hyperplasia. We speculate that PDE11A genetic defects may be associated with adrenal pathology in a wider than previously suspected clinical spectrum that includes asymptomatic individuals.


Assuntos
Adenoma/genética , Hiperfunção Adrenocortical/enzimologia , Hiperfunção Adrenocortical/genética , Variação Genética , Mutação , Diester Fosfórico Hidrolases/genética , Neoplasias Hipofisárias/genética , 3',5'-GMP Cíclico Fosfodiesterases , Adenoma/enzimologia , Sequência de Bases , Portador Sadio , Linhagem Celular , Códon sem Sentido , Síndrome de Cushing/enzimologia , Síndrome de Cushing/genética , DNA/genética , Primers do DNA , DNA de Neoplasias/genética , Frequência do Gene , Genótipo , Células HeLa , Humanos , Rim , Perda de Heterozigosidade , Neoplasias Hipofisárias/enzimologia
17.
Cancer Res ; 64(24): 8811-5, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15604237

RESUMO

Mutations of the human type Ialpha regulatory subunit (RIalpha) of cyclic AMP-dependent protein kinase (PKA; PRKAR1A) lead to altered kinase activity, primary pigmented nodular adrenocortical disease, and tumors of the thyroid and other tissues. To bypass the early embryonic lethality of Prkar1a(-/-) mice, we established transgenic mice carrying an antisense transgene for Prkar1a exon 2 (X2AS) under the control of a tetracycline-responsive promoter. Down-regulation of Prkar1a by up to 70% was achieved in transgenic mouse tissues and embryonic fibroblasts, with concomitant changes in kinase activity and increased cell proliferation, respectively. Mice developed thyroid follicular hyperplasia and adenomas, adrenocortical hyperplasia, and other features reminiscent of primary pigmented nodular adrenocortical disease, histiocytic and epithelial hyperplasias, lymphomas, and other mesenchymal tumors. These were associated with allelic losses of the mouse chromosome 11 Prkar1a locus, an increase in total type II PKA activity, and higher RIIbeta protein levels. This mouse provides a novel, useful tool for the investigation of cyclic AMP, RIalpha, and PKA functions and confirms the critical role of Prkar1a in tumorigenesis in endocrine and other tissues.


Assuntos
Neoplasias do Córtex Suprarrenal/enzimologia , Transtornos Linfoproliferativos/enzimologia , Proteínas/fisiologia , Neoplasias da Glândula Tireoide/enzimologia , Adenoma/enzimologia , Adenoma/genética , Neoplasias do Córtex Suprarrenal/genética , Animais , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico , DNA Antissenso/genética , Regulação para Baixo , Éxons , Feminino , Transtornos Linfoproliferativos/genética , Mesoderma/enzimologia , Mesoderma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Gravidez , Regiões Promotoras Genéticas , Proteínas/genética , Tetraciclina/farmacologia , Neoplasias da Glândula Tireoide/genética , Transativadores/genética
18.
J Clin Endocrinol Metab ; 90(9): 5134-40, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15941871

RESUMO

CONTEXT: We recently showed that pre- and postcontrast spoiled gradient-recalled acquisition in the steady-state (SPGR) was superior to conventional pre- and postcontrast T-1 weighted spin echo (SE) acquisition magnetic resonance imaging (MRI) for the diagnostic evaluation of pituitary tumors in adult patients. OBJECTIVE: The present investigation assessed the use of SPGR vs. SE-MRI in the diagnostic evaluation of ACTH-secreting tumors in children and adolescents with Cushing disease. DESIGN: Data were analyzed retrospectively from a series of patients seen over 7 yr (1997-2004). SETTING: The setting for this study was a tertiary care referral center. PATIENTS: Thirty children with Cushing disease (13 females and 17 males with a mean age of 12 +/- 3 yr) were studied. INTERVENTIONS AND OUTCOME MEASURES: Imaging results were compared with surgical and pathological findings and the clinical outcome. RESULTS: Twenty-eight patients had microadenomas, and two had macroadenomas; the latter were identified by both MRI techniques. Precontrast SE and SPGR-MRI identified four and six of the microadenomas, respectively. Postcontrast SPGR-MRI identified the location of the tumor in 18 of 28 patients, whereas postcontrast SE-MRI identified the location and accurately estimated the size of the tumor in only five patients (P < 0.001). CONCLUSIONS: We conclude that conventional MRI, even with contrast enhancement, mostly failed to identify ACTH-secreting microadenomas in children and adolescents with Cushing disease. Postcontrast SPGR-MRI was superior to SE-MRI and should be used in addition to conventional SE-MRI in the pituitary evaluation of children and adolescents with suspected Cushing disease.


Assuntos
Adenoma/diagnóstico , Adenoma/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Síndrome de Cushing/diagnóstico , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/metabolismo , Adenoma/patologia , Adenoma/cirurgia , Adolescente , Criança , Imagem Ecoplanar/normas , Reações Falso-Negativas , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Masculino , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
J Clin Invest ; 125(8): 3285-96, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26193635

RESUMO

BACKGROUND: Type 1 diabetes (T1D) results from destruction of pancreatic ß cells by autoreactive effector T cells. We hypothesized that the immunomodulatory drug alefacept would result in targeted quantitative and qualitative changes in effector T cells and prolonged preservation of endogenous insulin secretion by the remaining ß cells in patients with newly diagnosed T1D. METHODS: In a multicenter, randomized, double-blind, placebo-controlled trial, we compared alefacept (two 12-week courses of 15 mg/wk i.m., separated by a 12-week pause) with placebo in patients with recent onset of T1D. Endpoints were assessed at 24 months and included meal-stimulated C-peptide AUC, insulin use, hypoglycemic events, and immunologic responses. RESULTS: A total of 49 patients were enrolled. At 24 months, or 15 months after the last dose of alefacept, both the 4-hour and the 2-hour C-peptide AUCs were significantly greater in the treatment group than in the control group (P = 0.002 and 0.015, respectively). Exogenous insulin requirements were lower (P = 0.002) and rates of major hypoglycemic events were about 50% reduced (P < 0.001) in the alefacept group compared with placebo at 24 months. There was no apparent between-group difference in glycemic control or adverse events. Alefacept treatment depleted CD4+ and CD8+ central memory T cells (Tcm) and effector memory T cells (Tem) (P < 0.01), preserved Tregs, increased the ratios of Treg to Tem and Tcm (P < 0.01), and increased the percentage of PD-1+CD4+ Tem and Tcm (P < 0.01). CONCLUSIONS: In patients with newly diagnosed T1D, two 12-week courses of alefacept preserved C-peptide secretion, reduced insulin use and hypoglycemic events, and induced favorable immunologic profiles at 24 months, well over 1 year after cessation of therapy. TRIAL REGISTRATION: https://clinicaltrials.gov/ NCT00965458. FUNDING: NIH and Astellas.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Fármacos Dermatológicos/administração & dosagem , Diabetes Mellitus Tipo 1 , Memória Imunológica/efeitos dos fármacos , Proteínas Recombinantes de Fusão/administração & dosagem , Adolescente , Adulto , Alefacept , Peptídeo C/sangue , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Criança , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Fatores de Tempo
20.
J Clin Endocrinol Metab ; 89(7): 3173-82, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15240590

RESUMO

Cushing syndrome is uncommon in childhood and rare in infancy. We report the case of a 3-yr-old child who presented with symptoms of Cushing syndrome beginning shortly after birth. Her hypercortisolemia was cyclical, causing relapsing and remitting symptoms, which eventually led to suspicions of possible Munchausen syndrome by proxy. Investigation at the National Institutes of Health excluded exogenous administration of glucocorticoids and indicated ACTH-independent Cushing syndrome. Paradoxical response to dexamethasone stimulation (Liddle's test) suggested a diagnosis of primary pigmented nodular adrenocortical disease (PPNAD). After bilateral adrenalectomy, both glands showed micronodular adrenocortical hyperplasia, but histology was not consistent with typical PPNAD. DNA analysis of the coding sequences of the PRKAR1A gene (associated with PPNAD and Carney complex) and the GNAS gene (associated with McCune-Albright syndrome) showed no mutations. We conclude that hypercortisolemia in infancy may be caused by micronodular adrenocortical hyperplasia, which can be cyclical and confused with exogenous Cushing syndrome. A paradoxical rise of glucocorticoid excretion during Liddle's test may delineate these patients. Infantile micronodular disease has some features of PPNAD and may represent its early form; however, at least in the case of the patient reported here, micronodular hyperplasia was not caused by coding mutations of the PRKAR1A or GNAS genes or associated with typical histology or any other features of Carney complex or McCune-Albright syndrome and may represent a distinct entity.


Assuntos
Doenças do Córtex Suprarrenal/diagnóstico , Síndrome de Cushing/diagnóstico , Hidrocortisona/sangue , Periodicidade , Doenças do Córtex Suprarrenal/sangue , Doenças do Córtex Suprarrenal/patologia , Doenças do Córtex Suprarrenal/cirurgia , Glândulas Suprarrenais/patologia , Adrenalectomia , DNA de Neoplasias/análise , Diagnóstico Diferencial , Feminino , Seguimentos , Hormônios/sangue , Humanos , Hiperplasia , Recém-Nascido , Microscopia Eletrônica , Tomografia Computadorizada por Raios X
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