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1.
Int J Gen Med ; 17: 3003-3014, 2024.
Article in English | MEDLINE | ID: mdl-39011423

ABSTRACT

Type 1 diabetes (T1D) is a complex, chronic autoimmune disease that affects over 1.6 million people in the United States. It is now understood that T1D may be undetected for many years while the disease progresses quietly without producing symptoms. T1D can be identified through diabetes-related autoantibody screening and staged accordingly, enabling healthcare providers to identify high-risk individuals in the early stages of the disease and either provide a stage-specific intervention or offer clinical trial opportunities to preserve beta cell function and anticipate the onset of clinical T1D. Evidence-based clinical practice guidelines currently do not exist for routine diabetes-related autoantibody screening of individuals at risk of developing T1D or of the general population. The purpose of this article is to help clinicians acquire an understanding of the rationale and protocols recommended for identifying patients at risk of developing T1D and monitoring such patients for autoimmune markers and progression of disease from Stage 1 to Stage 3 (clinical disease).


Type 1 diabetes (T1D) is a life-long condition where the body's immune system (which normally fights infection) mistakenly attacks cells in the pancreas that make insulin. Insulin allows one to use energy from food and controls blood sugar levels. Without early recognition and treatment, high blood sugar can cause serious symptoms and life-threatening complications, such as diabetic ketoacidosis (DKA). DKA happens when there is very low insulin, and if not spotted early, it can cause coma and death. T1D can occur at any age. The chance of getting T1D is higher if another family member has it. T1D progresses silently for months or years before symptoms appear such as increased thirst, frequent urination, and unintentional weight loss. Healthcare providers can now screen and identify people who are at early stages of T1D (without symptoms) with blood tests called autoantibodies. Early detection through screening allows people to 1) learn about the disease before symptoms start and insulin is needed, 2) potentially receive treatments that delay T1D progression, and 3) participate in research trials. By detecting T1D at early stages, people can connect with the right care team and develop the skills needed to manage later stage T1D. Early detection has been shown to prevent hospitalization and life-threatening conditions. Screening for T1D will help people maximize their opportunities to delay T1D onset while preparing for diabetes care.

2.
Pediatr Res ; 95(1): 70-74, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37684431

ABSTRACT

BACKGROUND: The ACGME recently released its recommendation for updates to the program requirements for pediatrics. These updates proposed changes to allocation of resident clinical time and a greater emphasis on individualization. The potential impact of these changes on the training of physician-scientists is discussed. METHODS: Discussion of the proposed changes was held within the members of the National Pediatrician-Scientist Collaborative Workgroup, a group that represents scientists, trainees, program directors, chairs, and physician-scientist educators at nearly 30 residency programs from across the US with a focus on understanding and developing optimal approaches to physician-scientist training. Consideration was given to the both the personal and institutional impact of the proposal for physician-scientist development. RESULTS: Both threats and opportunities were identified. Key opportunities include the enhanced individualized training time that could be used to explore research. Threats include re-allocation of clinical training time that may strain institutions financially, expand clinical service requirements for other early career stage individuals, and alter exposure to a broad range of pediatric specialists and sub-specialists that impact career development. CONCLUSION: The NPSCW encourages consideration of the impact of changing program requirements on physician-scientist development to include ongoing discussion amongst mentors, programs, and trainees to understand and mitigate impact of new program requirements on the development of pediatrician-scientists.


Subject(s)
Biomedical Research , Internship and Residency , Physicians , Humans , Child , Biomedical Research/education , Pediatricians , Research Personnel/education
3.
J Med Genet ; 61(3): 232-238, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-37813462

ABSTRACT

BACKGROUND: The Ehlers-Danlos syndromes (EDS) are heritable disorders of connective tissue (HDCT), reclassified in the 2017 nosology into 13 subtypes. The genetic basis for hypermobile Ehlers-Danlos syndrome (hEDS) remains unknown. METHODS: Whole exome sequencing (WES) was undertaken on 174 EDS patients recruited from a national diagnostic service for complex EDS and a specialist clinic for hEDS. Patients had already undergone expert phenotyping, laboratory investigation and gene sequencing, but were without a genetic diagnosis. Filtered WES data were reviewed for genes underlying Mendelian disorders and loci reported in EDS linkage, transcriptome and genome-wide association studies (GWAS). A genetic burden analysis (Minor Allele Frequency (MAF) <0.05) incorporating 248 Avon Longitudinal Study of Parents and Children (ALSPAC) controls sequenced as part of the UK10K study was undertaken using TASER methodology. RESULTS: Heterozygous pathogenic (P) or likely pathogenic (LP) variants were identified in known EDS and Loeys-Dietz (LDS) genes. Multiple variants of uncertain significance where segregation and functional analysis may enable reclassification were found in genes associated with EDS, LDS, heritable thoracic aortic disease (HTAD), Mendelian disorders with EDS symptomatology and syndromes with EDS-like features. Genetic burden analysis revealed a number of novel loci, although none reached the threshold for genome-wide significance. Variants with biological plausibility were found in genes and pathways not currently associated with EDS or HTAD. CONCLUSIONS: We demonstrate the clinical utility of large panel-based sequencing and WES for patients with complex EDS in distinguishing rare EDS subtypes, LDS and related syndromes. Although many of the P and LP variants reported in this cohort would be identified with current panel testing, they were not at the time of this study, highlighting the use of extended panels and WES as a clinical tool for complex EDS. Our results are consistent with the complex genetic architecture of EDS and suggest a number of novel hEDS and HTAD candidate genes and pathways.


Subject(s)
Connective Tissue Diseases , Ehlers-Danlos Syndrome , Child , Humans , Genome-Wide Association Study , Longitudinal Studies , Ehlers-Danlos Syndrome/diagnosis , Ehlers-Danlos Syndrome/genetics
4.
Diabetes Care ; 47(3): 393-400, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38151474

ABSTRACT

OBJECTIVE: This multicenter prospective cohort study compared pancreas volume as assessed by MRI, metabolic scores derived from oral glucose tolerance testing (OGTT), and a combination of pancreas volume and metabolic scores for predicting progression to stage 3 type 1 diabetes (T1D) in individuals with multiple diabetes-related autoantibodies. RESEARCH DESIGN AND METHODS: Pancreas MRI was performed in 65 multiple autoantibody-positive participants enrolled in the Type 1 Diabetes TrialNet Pathway to Prevention study. Prediction of progression to stage 3 T1D was assessed using pancreas volume index (PVI), OGTT-derived Index60 score and Diabetes Prevention Trial-Type 1 Risk Score (DPTRS), and a combination of PVI and DPTRS. RESULTS: PVI, Index60, and DPTRS were all significantly different at study entry in 11 individuals who subsequently experienced progression to stage 3 T1D compared with 54 participants who did not experience progression (P < 0.005). PVI did not correlate with metabolic testing across individual study participants. PVI declined longitudinally in the 11 individuals diagnosed with stage 3 T1D, whereas Index60 and DPTRS increased. The area under the receiver operating characteristic curve for predicting progression to stage 3 from measurements at study entry was 0.76 for PVI, 0.79 for Index60, 0.79 for DPTRS, and 0.91 for PVI plus DPTRS. CONCLUSIONS: These findings suggest that measures of pancreas volume and metabolism reflect distinct components of risk for developing stage 3 type 1 diabetes and that a combination of these measures may provide superior prediction than either alone.


Subject(s)
Diabetes Mellitus, Type 1 , Humans , Diabetes Mellitus, Type 1/diagnosis , Prospective Studies , Pancreas/diagnostic imaging , Pancreas/metabolism , Risk Factors , Autoantibodies , Magnetic Resonance Imaging
6.
J Clin Endocrinol Metab ; 108(10): 2699-2707, 2023 09 18.
Article in English | MEDLINE | ID: mdl-36938587

ABSTRACT

CONTEXT: Individuals with type 1 diabetes (T1D) have a smaller pancreas, but longitudinal changes in pancreas size and shape are unclear. OBJECTIVE: We monitored changes in pancreas size and shape after diagnosis with T1D. DESIGN: We conducted a prospective cohort study at an academic medical center between 2014 and 2022. PATIENTS AND HEALTHY CONTROLS: Individuals with T1D (n = 91) or controls (n = 90) underwent magnetic resonance imaging (MRI) of the pancreas, including longitudinal MRI in 53 individuals with new-onset T1D. INTERVENTION: Interventions included MRI and continuous glucose monitoring (CGM). MAIN OUTCOME MEASURES: Pancreas size and shape were measured from MRI. For participants who used CGM, measures of glycemic variability were calculated. RESULTS: On longitudinal imaging, pancreas volume and pancreas volume index normalized for body weight declined during the first year after diagnosis. Pancreas volume index continued to decline through the fifth year after diagnosis. A cross-sectional study of individuals with diabetes duration up to 60 years demonstrated that pancreas size in adults negatively correlated with age and disease duration, whereas pancreas volume and pancreas volume index remained stable in controls. Pancreas volume index correlated inversely with low blood glucose index, a measure of risk for hypoglycemia. Pancreas shape was altered in individuals with T1D and further diverged from controls over the first 5 years after diagnosis. Pancreas size and shape are altered in nondiabetic individuals at genetic risk for T1D. Combined pancreas size and shape analysis better distinguished the pancreas of individuals with T1D from controls than size alone. CONCLUSIONS: Pancreas size declines most rapidly near the clinical diagnosis of T1D and continues to decline throughout adulthood. Declines in pancreas size are accompanied by changes in pancreas shape.


Subject(s)
Diabetes Mellitus, Type 1 , Adult , Humans , Blood Glucose , Blood Glucose Self-Monitoring/methods , Cross-Sectional Studies , Prospective Studies , Pancreas/diagnostic imaging , Magnetic Resonance Imaging
7.
Diabetes Care ; 46(5): 1005-1013, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36920087

ABSTRACT

OBJECTIVE: Previous studies showed that inhibiting lymphocyte costimulation reduces declining ß-cell function in individuals newly diagnosed with type 1 diabetes. We tested whether abatacept would delay or prevent progression of type 1 diabetes from normal glucose tolerance (NGT) to abnormal glucose tolerance (AGT) or to diabetes and the effects of treatment on immune and metabolic responses. RESEARCH DESIGN AND METHODS: We conducted a phase 2, randomized, placebo-controlled, double-masked trial of abatacept in antibody-positive participants with NGT who received monthly abatacept/placebo infusions for 12 months. The end point was AGT or diabetes, assessed by oral glucose tolerance tests. RESULTS: A total of 101 participants received abatacept and 111 placebo. Of these, 81 (35 abatacept and 46 placebo) met the end point of AGT or type 1 diabetes diagnosis (hazard ratio 0.702; 95% CI 0.452, 1.09; P = 0.11) The C-peptide responses to oral glucose tolerance tests were higher in the abatacept arm (P < 0.03). Abatacept reduced the frequency of inducible T-cell costimulatory (ICOS)+ PD1+ T-follicular helper (Tfh) cells during treatment (P < 0.0001), increased naive CD4+ T cells, and also reduced the frequency of CD4+ regulatory T cells (Tregs) from the baseline (P = 0.0067). Twelve months after treatment, the frequency of ICOS+ Tfh, naive CD4+ T cells, and Tregs returned to baseline. CONCLUSIONS: Although abatacept treatment for 1 year did not significantly delay progression to glucose intolerance in at-risk individuals, it impacted immune cell subsets and preserved insulin secretion, suggesting that costimulation blockade may modify progression of type 1 diabetes.


Subject(s)
Diabetes Mellitus, Type 1 , Humans , Abatacept/therapeutic use , Abatacept/pharmacology , Diabetes Mellitus, Type 1/drug therapy , Immunosuppressive Agents , T-Lymphocytes, Regulatory , Glucose/therapeutic use
8.
Diabetes Care ; 46(4): 773-776, 2023 04 01.
Article in English | MEDLINE | ID: mdl-36724370

ABSTRACT

OBJECTIVE: To determine the mechanism of reduced pancreas size in type 1 diabetes and the significance of islet-derived insulin in pancreatic growth. RESEARCH DESIGN AND METHODS: Using a validated and standardized MRI protocol, we measured pancreas volume and shape in a family with an autosomal-dominant insulin gene mutation that results in insulin deficiency similar in severity to that of type 1 diabetes but without autoimmunity. DNA sequencing confirmed the mutation in all four affected individuals and none of the four control family members. Insulin secretory capacity was determined by measuring postprandial urinary C-peptide. RESULTS: Family members with this form of monogenic diabetes had a markedly smaller pancreas and a severely impaired postprandial C-peptide level than family members without diabetes. CONCLUSIONS: These results suggest that severe insulin deficiency, rather than islet-directed autoimmunity, leads to reduced pancreas size in type 1 diabetes and that insulin is a major trophic factor for the exocrine pancreas.


Subject(s)
Diabetes Mellitus, Type 1 , Insulin , Pancreas , Diabetes Mellitus, Type 1/diagnostic imaging , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/pathology , Organ Size , Insulin/deficiency , Insulin/genetics , Pancreas/diagnostic imaging , Pancreas/pathology , Pedigree , Magnetic Resonance Imaging , Heterozygote , Humans , Male , Female , Adult , Middle Aged , Mutation
9.
Diabetes Care ; 45(10): 2406-2411, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35944264

ABSTRACT

OBJECTIVE: Although mortality from coronavirus disease 2019 (COVID-19) among youth with type 1 diabetes is rare, severe acute respiratory syndrome coronavirus 2 is associated with increased pediatric hospitalizations for diabetic ketoacidosis (DKA). To clarify whether the relationship between COVID-19 and DKA is coincidental or causal, we compared tissue glucose disposal (TGD) during standardized treatment for DKA between pediatric patients with COVID-19 and those without COVID-19. RESEARCH DESIGN AND METHODS: We retrospectively compared TGD during standardized therapy for DKA in all children with preexisting type 1 diabetes with or without COVID-19. Cases were assessed beginning with the first case of COVID-19-positive DKA on 19 June 2020 through 2 February 2022. RESULTS: We identified 93 COVID-19-negative patients and 15 COVID-19-positive patients who were treated for DKA, with similar baseline characteristics between groups. Median TGD was 46% lower among patients who had COVID-19 compared with those who did not (P = 0.013). CONCLUSIONS: These results suggest that COVID-19 provokes a metabolic derangement over and above factors that typically contribute to pediatric DKA. These findings underscore the significant and direct threat posed by COVID-19 in pediatric type 1 diabetes and emphasize the importance of mitigation and monitoring including through vaccination as a primary prevention.


Subject(s)
COVID-19 , Diabetes Mellitus, Type 1 , Diabetic Ketoacidosis , Insulin Resistance , Adolescent , COVID-19/complications , Child , Diabetes Mellitus, Type 1/complications , Diabetic Ketoacidosis/etiology , Diabetic Ketoacidosis/therapy , Glucose , Humans , Retrospective Studies
10.
Pediatr Diabetes ; 23(7): 1088-1100, 2022 11.
Article in English | MEDLINE | ID: mdl-36004391

ABSTRACT

OBJECTIVE: Despite enthusiasm for low carbohydrate diets (LCDs) among patients with type 1 diabetes (T1DM), no prospective study has investigated outcomes in adolescent T1DM. We aimed to quantify a pragmatic LCD intervention's impact on glycemia, lipidemia, and quality of life (QOL) in adolescents with T1DM. RESEARCH DESIGN AND METHODS: At an academic center, we randomized 39 patients with T1DM aged 13-21 years to one of three 12-week interventions: an LCD, an isocaloric standard carbohydrate diet (SCD), or general diabetes education without a prescriptive diet. Glycemic outcomes included glycosylated hemoglobin (HbA1c) and continuous glucose monitoring. RESULTS: There were no significant differences in glycemic, lipidemic, or QOL parameters between groups at any timepoint. Median HbA1c was similar at baseline between groups and did not change appreciably (7.9%-8.4% in LCDs, 7.9%-7.9% in SCDs, and 8.2%-7.8% in controls). Change in carbohydrate consumption was minimal with only one participant reaching target carbohydrate intake. CONCLUSIONS: This pragmatic LCD intervention did not alter carbohydrate consumption or glycemia. Although this study was unable to evaluate a highly controlled LCD, it indicates that adolescents are unlikely to implement an educational LCD intervention in routine clinic settings. Thus, this approach is unlikely to effectively mitigate hyperglycemia in adolescents.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Adolescent , Blood Glucose , Blood Glucose Self-Monitoring , Diabetes Mellitus, Type 1/therapy , Diet, Carbohydrate-Restricted , Glycated Hemoglobin/analysis , Humans , Quality of Life , Young Adult
11.
Sci Rep ; 12(1): 11731, 2022 07 11.
Article in English | MEDLINE | ID: mdl-35821261

ABSTRACT

The immune system of healthy individuals is capable of regulating autoimmunity through multiple mechanisms. In Type 1 Diabetes (T1D) we recently discovered natural IgM, although present at normal levels, is unable to perform its normal immunoregulatory function. Treating diabetic mice with IgM from healthy donors led to reversal of disease without immune depletion. To investigate the therapeutic potential of a human preparation of IgM, we administered an IgM-enriched preparation of immunoglobulin called Pentaglobin. Administration of Pentaglobin therapy reversed disease in diabetic NOD mice and boosted CD4 + Foxp3 + Tregs. Importantly, the impact of Pentaglobin on the immune system was limited to inhibiting beta cell destruction but was not immune depleting nor did it inhibit the immunization response to an irrelevant antigen. These findings indicate that inhibition of deleterious autoimmunity in T1D is possible while leaving protective immunity fully intact.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 1 , Animals , Diabetes Mellitus, Experimental/drug therapy , Humans , Immunoglobulin A , Immunoglobulin M , Mice , Mice, Inbred NOD
12.
F S Sci ; 3(2): 148-158, 2022 05.
Article in English | MEDLINE | ID: mdl-35560012

ABSTRACT

OBJECTIVE: To determine the impact of autoimmunity in the absence of glycemic alterations on pregnancy in type 1 diabetes (T1D). DESIGN: Because nonobese diabetic (NOD) mice experience autoimmunity before the onset of hyperglycemia, we studied pregnancy outcomes in prediabetic NOD mice using flow cytometry and enzyme-linked immunosorbent assays. Once we determined that adverse events in pregnancy occurred in euglycemic mice, we performed an exploratory study using electronic health records to better understand pregnancy complications in humans with T1D and normal hemoglobin A1c levels. SETTING: University Medical Center. PATIENT(S)/ANIMAL(S): Nonobese diabetic mice and electronic health records from Vanderbilt University Medical Center. INTERVENTION(S): Nonobese diabetic mice were administered 200 µg of an anti-interleukin 6 (IL-6) antibody every other day starting on day 5 of gestation. MAIN OUTCOME MEASURE(S): Changes in the number of abnormal and reabsorbed pups in NOD mice and odds of vascular complications in pregnancy in T1D in relation to A1c. RESULT(S): Prediabetic NOD mice had increased adverse pregnancy outcomes compared with nonautoimmune mice; blockade of IL-6, which was secreted by endothelial cells, decreased the number of reabsorbed and abnormal fetuses. Similarly, vascular complications were increased in pregnant patients with T1D across all A1c values. CONCLUSION(S): The vascular secretion of IL-6 drives adverse pregnancy outcomes in prediabetic NOD mice. Pregnant patients with T1D have increased vascular complications even with normal hemoglobin A1cs, indicating a potential effect of autoimmunity on the placental vasculature.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 1 , Prediabetic State , Animals , Endothelial Cells , Female , Glycated Hemoglobin , Humans , Interleukin-6 , Mice , Mice, Inbred NOD , Placenta , Pregnancy
14.
BMC Med Imaging ; 22(1): 5, 2022 01 05.
Article in English | MEDLINE | ID: mdl-34986790

ABSTRACT

Pancreas volume is reduced in individuals with diabetes and in autoantibody positive individuals at high risk for developing type 1 diabetes (T1D). Studies investigating pancreas volume are underway to assess pancreas volume in large clinical databases and studies, but manual pancreas annotation is time-consuming and subjective, preventing extension to large studies and databases. This study develops deep learning for automated pancreas volume measurement in individuals with diabetes. A convolutional neural network was trained using manual pancreas annotation on 160 abdominal magnetic resonance imaging (MRI) scans from individuals with T1D, controls, or a combination thereof. Models trained using each cohort were then tested on scans of 25 individuals with T1D. Deep learning and manual segmentations of the pancreas displayed high overlap (Dice coefficient = 0.81) and excellent correlation of pancreas volume measurements (R2 = 0.94). Correlation was highest when training data included individuals both with and without T1D. The pancreas of individuals with T1D can be automatically segmented to measure pancreas volume. This algorithm can be applied to large imaging datasets to quantify the spectrum of human pancreas volume.


Subject(s)
Deep Learning , Diabetes Mellitus, Type 1/diagnostic imaging , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Pancreas/diagnostic imaging , Adolescent , Algorithms , Diabetes Mellitus, Type 1/pathology , Humans , Imaging, Three-Dimensional/methods , Male , Organ Size , Pancreas/pathology , Retrospective Studies
15.
Dev Biol ; 481: 43-51, 2022 01.
Article in English | MEDLINE | ID: mdl-34555363

ABSTRACT

Developmental patterning is thought to be regulated by conserved signalling pathways. Initial patterns are often broad before refining to only those cells that commit to a particular fate. However, the mechanisms by which pattern refinement takes place remain to be addressed. Using the posterior crossvein (PCV) of the Drosophila pupal wing as a model, into which bone morphogenetic protein (BMP) ligand is extracellularly transported to instruct vein patterning, we investigate how pattern refinement is regulated. We found that BMP signalling induces apical enrichment of Myosin II in developing crossvein cells to regulate apical constriction. Live imaging of cellular behaviour indicates that changes in cell shape are dynamic and transient, only being maintained in those cells that retain vein fate competence after refinement. Disrupting cell shape changes throughout the PCV inhibits pattern refinement. In contrast, disrupting cell shape in only a subset of vein cells can result in a loss of BMP signalling. We propose that mechano-chemical feedback leads to competition for the developmental signal which plays a critical role in pattern refinement.


Subject(s)
Body Patterning , Bone Morphogenetic Proteins/metabolism , Drosophila Proteins/metabolism , Gene Expression Regulation, Developmental , Signal Transduction , Animals , Bone Morphogenetic Proteins/genetics , Drosophila Proteins/genetics , Drosophila melanogaster , Pupa , Wings, Animal
18.
Am J Reprod Immunol ; 86(6): e13501, 2021 12.
Article in English | MEDLINE | ID: mdl-34570418

ABSTRACT

Group B Streptococcus (GBS), also known as Streptococcus agalactiae is a Gram-positive bacterium commonly encountered as part of the microbiota within the human gastrointestinal tract. A common cause of infections during pregnancy, GBS is responsible for invasive diseases ranging from urinary tract infections to chorioamnionitis and neonatal sepsis. Diabetes mellitus (DM) is a chronic disease resulting from impaired regulation of blood glucose levels. The incidence of DM has steadily increased worldwide to affecting over 450 million people. Poorly controlled DM is associated with multiple health comorbidities including an increased risk for infection. Epidemiologic studies have clearly demonstrated that DM correlates with an increased risk for invasive GBS infections, including skin and soft tissue infections and sepsis in non-pregnant adults. However, the impact of DM on risk for invasive GBS urogenital infections, particularly during the already vulnerable time of pregnancy, is less clear. We review the evolving epidemiology, immunology, and pathophysiology of GBS urogenital infections including rectovaginal colonization during pregnancy, neonatal infections of infants exposed to DM in utero, and urinary tract infections in pregnant and non-pregnant adults in the context of DM and highlight in vitro studies examining why DM might increase risk for GBS urogenital infection.


Subject(s)
Immunocompromised Host , Pregnancy Complications, Infectious/immunology , Pregnancy in Diabetics/immunology , Streptococcal Infections/immunology , Female , Humans , Pregnancy , Streptococcus agalactiae
19.
JCI Insight ; 6(19)2021 10 08.
Article in English | MEDLINE | ID: mdl-34403367

ABSTRACT

Autoimmune disease has presented an insurmountable barrier to restoration of durable immune tolerance. Previous studies indicate that chronic therapy with metabolic inhibitors can reduce autoimmune inflammation, but it remains unknown whether acute metabolic modulation enables permanent immune tolerance to be established. In an animal model of lupus, we determined that targeting glucose metabolism with 2-deoxyglucose (2DG) and mitochondrial metabolism with metformin enables endogenous immune tolerance mechanisms to respond to tolerance induction. A 2-week course of 2DG and metformin, when combined with tolerance-inducing therapy anti-CD45RB, prevented renal deposition of autoantibodies for 6 months after initial treatment and restored tolerance induction to allografts in lupus-prone mice. The restoration of durable immune tolerance was linked to changes in T cell surface glycosylation patterns, illustrating a role for glycoregulation in immune tolerance. These findings indicate that metabolic therapy may be applied as a powerful preconditioning to reinvigorate tolerance mechanisms in autoimmune and transplant settings that resist current immune therapies.


Subject(s)
Antimetabolites/pharmacology , CD4-Positive T-Lymphocytes/immunology , Deoxyglucose/pharmacology , Hypoglycemic Agents/pharmacology , Immune Tolerance/drug effects , Kidney/drug effects , Leukocyte Common Antigens/immunology , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/metabolism , Metformin/pharmacology , Animals , Antibodies/pharmacology , Disease Models, Animal , Glycolysis/drug effects , Glycosylation/drug effects , Immune Tolerance/immunology , Kidney/immunology , Leukocyte Common Antigens/antagonists & inhibitors , Mice , Oxidative Phosphorylation/drug effects , Transplantation Tolerance/drug effects , Transplantation Tolerance/immunology , Transplantation, Homologous
20.
PLoS One ; 16(8): e0256029, 2021.
Article in English | MEDLINE | ID: mdl-34428220

ABSTRACT

Magnetic resonance imaging (MRI) has detected changes in pancreas volume and other characteristics in type 1 and type 2 diabetes. However, differences in MRI technology and approaches across locations currently limit the incorporation of pancreas imaging into multisite trials. The purpose of this study was to develop a standardized MRI protocol for pancreas imaging and to define the reproducibility of these measurements. Calibrated phantoms with known MRI properties were imaged at five sites with differing MRI hardware and software to develop a harmonized MRI imaging protocol. Subsequently, five healthy volunteers underwent MRI at four sites using the harmonized protocol to assess pancreas size, shape, apparent diffusion coefficient (ADC), longitudinal relaxation time (T1), magnetization transfer ratio (MTR), and pancreas and hepatic fat fraction. Following harmonization, pancreas size, surface area to volume ratio, diffusion, and longitudinal relaxation time were reproducible, with coefficients of variation less than 10%. In contrast, non-standardized image processing led to greater variation in MRI measurements. By using a standardized MRI image acquisition and processing protocol, quantitative MRI of the pancreas performed at multiple locations can be incorporated into clinical trials comparing pancreas imaging measures and metabolic state in individuals with type 1 or type 2 diabetes.


Subject(s)
Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/standards , Pancreas/diagnostic imaging , Adult , Diffusion Magnetic Resonance Imaging/methods , Female , Healthy Volunteers , Humans , Image Processing, Computer-Assisted , Male , Phantoms, Imaging , Prospective Studies , Reproducibility of Results
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