Cost-effectiveness of a Novel Hypoglycaemia Programme: The 'HARPdoc vs BGAT' RCT

AIMS

To assess the cost-effectiveness of HARPdoc (Hypoglycaemia Awareness Restoration Programme for adults with type 1 diabetes and problematic hypoglycaemia despite optimised care), focussed upon cognitions and motivation, versus BGAT (Blood Glucose Awareness Training), focussed on behaviours and education, as adjunctive treatments for treatment-resistant problematic hypoglycaemia in type 1 diabetes, in a randomised controlled trial.

METHODS

Eligible adults were randomised to either intervention. Quality of life (QoL, measured using EQ-5D-5L); cost of utilisation of health services (using the adult services utilization schedule, AD-SUS) and of programme implementation and curriculum delivery were measured. A cost-utility analysis was undertaken using quality-adjusted life years (QALYs) as a measure of trial participant outcome and cost-effectiveness was evaluated with reference to the incremental net benefit (INB) of HARPdoc compared to BGAT.

RESULTS

Over 24 months mean total cost per participant was £194 lower for HARPdoc compared to BGAT (95% CI: -£2498 to £1942). HARPdoc was associated with a mean incremental gain of 0.067 QALYs/participant over 24 months post-randomisation: an equivalent gain of 24 days in full health. The mean INB of HARPdoc compared to BGAT over 24 months was positive: £1521/participant, indicating comparative cost-effectiveness, with an 85% probability of correctly inferring an INB > 0.

CONCLUSIONS

Addressing health cognitions in people with treatment-resistant hypoglycaemia achieved cost-effectiveness compared to an alternative approach through improved QoL and reduced need for medical services, including hospital admissions. Compared to BGAT, HARPdoc offers a cost-effective adjunct to educational and technological solutions for problematic hypoglycaemia.

Profiles of disordered eating behaviour in type 1 diabetes using the DEPS-R and behaviour and glycaemic outcomes in a real-life setting

AIMS

The Diabetes Eating Problems Survey - Revised (DEPS-R) is commonly used to assess disordered eating behaviour (DEB) in individuals with type 1 diabetes and has advantages compared to other measures not specifically tailored to diabetes. A score ≥20 on the DEPS-R is used to indicate clinically significant DEB; however, it does not distinguish between eating disorder (ED) phenotypes necessary to guide treatment decisions, limiting clinical utility.

METHODS

The current study used latent class analysis to identify distinct person-centred profiles of DEB in adults with type 1 diabetes using the DEPS-R. Analysis of Variance with Games Howell post-hoc comparisons was then conducted to examine the correspondence between the profiles and binge eating, insulin restriction and glycaemic control (HbA1c, mean blood glucose, and percent time spent in hyperglycaemia) during 3 days of assessment in a real-life setting.

RESULTS

Latent class analysis indicated a 4-class solution, with patterns of item endorsement suggesting the following profiles: Bulimia, Binge Eating, Overeating and Low Pathology. Differences in binge eating, insulin restriction and glycaemic control were observed between profiles during 3 days of at-home assessment. The Bulimia profile was associated with highest HbA1c and 3-day mean blood glucose.

CONCLUSIONS

There are common patterns of responses on the DEPS-R that appear to reflect different ED phenotypes. Profiles based on the DEPS-R corresponded with behaviour in the real-life setting as expected and were associated with different glycaemic outcomes. Results may have implications for the use of the DEPS-R in research and clinical settings.

A multi-ancestry genome-wide association study in type 1 diabetes

Type 1 diabetes (T1D) is an autoimmune disease caused by destruction of the pancreatic β-cells. Genome-wide association (GWAS) and fine mapping studies have been conducted mainly in European ancestry (EUR) populations. We performed a multi-ancestry GWAS to identify SNPs and HLA alleles associated with T1D risk and age at onset. EUR families (N = 3223), and unrelated individuals of African (AFR, N = 891) and admixed (Hispanic/Latino) ancestry (AMR, N = 308) were genotyped using the Illumina HumanCoreExome BeadArray, with imputation to the TOPMed reference panel. The Multi-Ethnic HLA reference panel was utilized to impute HLA alleles and amino acid residues. Logistic mixed models (T1D risk) and frailty models (age at onset) were used for analysis. In GWAS meta-analysis, seven loci were associated with T1D risk at genome-wide significance: PTPN22, HLA-DQA1, IL2RA, RNLS, INS, IKZF4-RPS26-ERBB3, and SH2B3, with four associated with T1D age at onset (PTPN22, HLA-DQB1, INS, and ERBB3). AFR and AMR meta-analysis revealed NRP1 as associated with T1D risk and age at onset, although NRP1 variants were not associated in EUR ancestry. In contrast, the PTPN22 variant was significantly associated with risk only in EUR ancestry. HLA alleles and haplotypes most significantly associated with T1D risk in AFR and AMR ancestry differed from that seen in EUR ancestry; in addition, the HLA-DRB1*08:02-DQA1*04:01-DQB1*04:02 haplotype was 'protective' in AMR while HLA-DRB1*08:01-DQA1*04:01-DQB1*04:02 haplotype was 'risk' in EUR ancestry, differing only at HLA-DRB1*08. These results suggest that much larger sample sizes in non-EUR populations are required to capture novel loci associated with T1D risk.

Monocytes in type 1 diabetes families exhibit high cytolytic activity and subset abundances that correlate with clinical progression

Monocytes are immune regulators implicated in the pathogenesis of type 1 diabetes (T1D), an autoimmune disease that targets insulin-producing pancreatic β cells. We determined that monocytes of recent onset (RO) T1D patients and their healthy siblings express proinflammatory/cytolytic transcriptomes and hypersecrete cytokines in response to lipopolysaccharide exposure compared to unrelated healthy controls (uHCs). Flow cytometry measured elevated circulating abundances of intermediate monocytes and >2-fold more CD14+CD16+HLADR+KLRD1+PRF1+ NK-like monocytes among patients with ROT1D compared to uHC. The intermediate to nonclassical monocyte ratio among ROT1D patients correlated with the decline in functional β cell mass during the first 24 months after onset. Among sibling nonprogressors, temporal decreases were measured in the intermediate to nonclassical monocyte ratio and NK-like monocyte abundances; these changes coincided with increases in activated regulatory T cells. In contrast, these monocyte populations exhibited stability among T1D progressors. This study associates heightened monocyte proinflammatory/cytolytic activity with T1D susceptibility and progression and offers insight to the age-dependent decline in T1D susceptibility.

Zinc-chelating BET bromodomain inhibitors equally target islet endocrine cell types

Inhibition of the bromodomain and extraterminal domain (BET) protein family is a potential strategy to prevent and treat diabetes; however, the clinical use of BET bromodomain inhibitors (BETi) is associated with adverse effects. Here, we explore a strategy for targeting BETi to β-cells by exploiting the high zinc (Zn2+) concentration in β-cells relative to other cell types. We report the synthesis of a novel, Zn2+-chelating derivative of the pan-BETi (+)-JQ1, (+)-JQ1-DPA, in which (+)-JQ1 was conjugated to dipicolyl amine (DPA). As controls, we synthesized (+)-JQ1-DBA, a non-Zn2+-chelating derivative, and (-)-JQ1-DPA, an inactive enantiomer that chelates Zn2+. Molecular modeling and biophysical assays showed that (+)-JQ1-DPA and (+)-JQ1-DBA retain potent binding to BET bromodomains in vitro. Cellular assays demonstrated (+)-JQ1-DPA attenuated NF-ĸB target gene expression in β-cells stimulated with the pro-inflammatory cytokine interleukin 1β. To assess β-cell selectivity, we isolated islets from a mouse model that expresses green fluorescent protein in insulin-positive β-cells and mTomato in insulin-negative cells (non-β-cells). Surprisingly, Zn2+-chelation did not confer β-cell selectivity as (+)-JQ1-DPA was equally effective in both β- and α-cells; however, (+)-JQ1-DPA was less effective in macrophages, a non-endocrine islet cell type. Intriguingly, the non-Zn2+-chelating derivative (+)-JQ1-DBA displayed the opposite selectivity, with greater effect in macrophages compared to (+)-JQ1-DPA, suggesting potential as a macrophage-targeting molecule. These findings suggest that Zn2+-chelating small molecules confer endocrine cell selectivity rather than β-cell selectivity in pancreatic islets and provide valuable insights and techniques to assess Zn2+-chelation as an approach to selectively target small molecules to pancreatic β-cells.

Time spent outdoors in childhood related to myopia among young adults in the Swedish ABIS cohort

PURPOSE

Elucidate the prevalence of myopia among young adults from a birth cohort of Swedish children and its relationship to possible risk factors during their childhood.

METHODS

Five thousand two hundred young adults, mean 23.4 years and 58% females, participating in the prospective birth cohort All Babies in Southeast Sweden (ABIS) answered a questionnaire including questions regarding health and physical activity, spectacle use, myopia and age at first optical correction. Questionnaires at previous follow-ups at ages 2-3, 5-6 and 8 years included information on type of housing, time outdoors, screen time and hours of reading. Myopia prevalence and associations with potential risk factors were analysed in univariate and multivariate regression models with Bonferroni's correction of p-values.

RESULTS

In the ABIS Swedish birth cohort of young adults, the prevalence of myopia was 29%. A univariate logistic regression showed a higher odds ratio for myopia with female gender (OR 1.59; p < 0.05) and a completed and started university education (OR 1.52; p < 0.05). Significantly lower odds ratios were found for hours spent outdoors at 8 years of age (OR 0.82; p < 0.05). Multivariate logistic regression showed a higher odds ratio for myopia in females (OR 1.52-1.57; p < 0.05) and completed and started university education (OR 1.34-1.49; p < 0.05) in all models. In a model including accommodative effort, measured in diopter hours at 8 years of age, hours spent outdoors were associated with a lower odds ratio for myopia (OR 0.86; p < 0.05). No association could be detected between myopia and the type of housing or near work.

CONCLUSION

The prevalence of myopia among young adults in a Swedish birth cohort was lower or unchanged compared to previous data. Female gender, higher education and less time spent outdoors in childhood were associated with an increased risk of developing myopia. Recommendations from child health services and schools should be given to stimulate children to spend enough time outdoors.

MetaboAnalyst 6.0: towards a unified platform for metabolomics data processing, analysis and interpretation

We introduce MetaboAnalyst version 6.0 as a unified platform for processing, analyzing, and interpreting data from targeted as well as untargeted metabolomics studies using liquid chromatography - mass spectrometry (LC-MS). The two main objectives in developing version 6.0 are to support tandem MS (MS2) data processing and annotation, as well as to support the analysis of data from exposomics studies and related experiments. Key features of MetaboAnalyst 6.0 include: (i) a significantly enhanced Spectra Processing module with support for MS2 data and the asari algorithm; (ii) a MS2 Peak Annotation module based on comprehensive MS2 reference databases with fragment-level annotation; (iii) a new Statistical Analysis module dedicated for handling complex study design with multiple factors or phenotypic descriptors; (iv) a Causal Analysis module for estimating metabolite - phenotype causal relations based on two-sample Mendelian randomization, and (v) a Dose-Response Analysis module for benchmark dose calculations. In addition, we have also improved MetaboAnalyst's visualization functions, updated its compound database and metabolite sets, and significantly expanded its pathway analysis support to around 130 species. MetaboAnalyst 6.0 is freely available at https://www.metaboanalyst.ca.

Endothelial NOX5 Obliterates the Reno-Protective Effect of Nox4 Deletion by Promoting Renal Fibrosis via Activation of EMT and ROS-Sensitive Pathways in Diabetes

Chronic hyperglycemia induces intrarenal oxidative stress due to the excessive production of reactive oxygen species (ROS), leading to a cascade of events that contribute to the development and progression of diabetic kidney disease (DKD). NOX5, a pro-oxidant NADPH oxidase isoform, has been identified as a significant contributor to renal ROS in humans. Elevated levels of renal ROS contribute to endothelial cell dysfunction and associated inflammation, causing increased endothelial permeability, which can disrupt the renal ecosystem, leading to progressive albuminuria and renal fibrosis in DKD. This study specifically examines the contribution of endothelial cell-specific human NOX5 expression in renal pathology in a transgenic mouse model of DKD. This study additionally compares NOX5 with the previously characterized NADPH oxidase, NOX4, in terms of their relative roles in DKD. Regardless of NOX4 pathway, this study found that endothelial cell-specific expression of NOX5 exacerbates renal injury, albuminuria and fibrosis. This is attributed to the activation of the endothelial mesenchymal transition (EMT) pathway via enhanced ROS formation and the modulation of redox-sensitive factors. These findings underscore the potential therapeutic significance of NOX5 inhibition in human DKD. The study proposes that inhibiting NOX5 could be a promising approach for mitigating the progression of DKD and strengthens the case for the development of NOX5-specific inhibitors as a potential therapeutic intervention.

Metabolomic associations of impaired awareness of hypoglycaemia in type 1 diabetes

This study investigates impaired awareness of hypoglycaemia (IAH), a complication of insulin therapy affecting 20-40% of individuals with type 1 diabetes. The exact pathophysiology is unclear, therefore we sought to identify metabolic signatures in IAH to elucidate potential pathophysiological pathways. Plasma samples from 578 individuals of the Dutch type 1 diabetes biomarker cohort, 67 with IAH and 108 without IAH (NAH) were analysed using the targeted metabolomics Biocrates AbsoluteIDQ p180 assay. Eleven metabolites were significantly associated with IAH. Genome-wide association studies of these 11 metabolites identified significant single nucleotide polymorphisms (SNPs) in C22:1-OH and phosphatidylcholine diacyl C36:6. After adjusting for the SNPs, 11 sphingomyelins and phosphatidylcholines were significantly higher in the IAH group in comparison to NAH. These metabolites are important components of the cell membrane and have been implicated to play a role in cell signalling in diabetes. These findings demonstrate the potential role of phosphatidylcholine and sphingomyelins in IAH.

Caloric restriction for the immunometabolic control of human health

Nutrition affects all physiological processes occurring in our body, including those related to the function of the immune system; indeed, metabolism has been closely associated with the differentiation and activity of both innate and adaptive immune cells. While excessive energy intake and adiposity have been demonstrated to cause systemic inflammation, several clinical and experimental evidence show that calorie restriction (CR), not leading to malnutrition, is able to delay aging and exert potent anti-inflammatory effects in different pathological conditions. This review provides an overview of the ability of different CR-related nutritional strategies to control autoimmune, cardiovascular, and infectious diseases, as tested by preclinical studies and human clinical trials, with a specific focus on the immunological aspects of these interventions. In particular, we recapitulate the state of the art on the cellular and molecular mechanisms pertaining to immune cell metabolic rewiring, regulatory T cell expansion, and gut microbiota composition, which possibly underline the beneficial effects of CR. Although studies are still needed to fully evaluate the feasibility and efficacy of the nutritional intervention in clinical practice, the experimental observations discussed here suggest a relevant role of CR in lowering the inflammatory state in a plethora of different pathologies, thus representing a promising therapeutic strategy for the control of human health.

Increased Diabetes Complications in a Mouse Model of Oxidative Stress Due to 'Mismatched' Mitochondrial DNA

Associations between chronic diabetes complications and mitochondrial dysfunction represent a subject of major importance, given the diabetes pandemic and high personal and socioeconomic costs of diabetes and its complications. Modelling diabetes complications in inbred laboratory animals is challenging due to incomplete recapitulation of human features, but offer mechanistic insights and preclinical testing. As mitochondrial-based oxidative stress is implicated in human diabetic complications, herein we evaluate diabetes in a unique mouse model that harbors a mitochondrial DNA from a divergent mouse species (the 'xenomitochondrial mouse'), which has mild mitochondrial dysfunction and increased oxidative stress. We use the streptozotocin-induced diabetes model with insulin supplementation, with 20-weeks diabetes. We compare C57BL/6 mice and the 'xenomitochondrial' mouse, with measures of heart and kidney function, histology, and skin oxidative stress markers. Compared to C57BL/6 mice, the xenomitochondrial mouse has increased diabetic heart and kidney damage, with cardiac dysfunction, and increased cardiac and renal fibrosis. Our results show that mitochondrial oxidative stress consequent to divergent mtDNA can worsen diabetes complications. This has implications for novel therapeutics to counter diabetes complications, and for genetic studies of risk, as mtDNA genotypes may contribute to clinical outcomes.

Integrative analysis of pathogenic variants in glucose-6-phosphatase based on an AlphaFold2 model

Mediating the terminal reaction of gluconeogenesis and glycogenolysis, the integral membrane protein glucose-6-phosphate catalytic subunit 1 (G6PC1) regulates hepatic glucose production by catalyzing hydrolysis of glucose-6-phosphate (G6P) within the lumen of the endoplasmic reticulum. Consistent with its vital contribution to glucose homeostasis, inactivating mutations in G6PC1 causes glycogen storage disease (GSD) type 1a characterized by hepatomegaly and severe hypoglycemia. Despite its physiological importance, the structural basis of G6P binding to G6PC1 and the molecular disruptions induced by missense mutations within the active site that give rise to GSD type 1a are unknown. In this study, we determine the atomic interactions governing G6P binding as well as explore the perturbations imposed by disease-linked missense variants by subjecting an AlphaFold2 G6PC1 structural model to molecular dynamics simulations and in silico predictions of thermodynamic stability validated with robust in vitro and in situ biochemical assays. We identify a collection of side chains, including conserved residues from the signature phosphatidic acid phosphatase motif, that contribute to a hydrogen bonding and van der Waals network stabilizing G6P in the active site. The introduction of GSD type 1a mutations modified the thermodynamic landscape, altered side chain packing and substrate-binding interactions, and induced trapping of catalytic intermediates. Our results, which corroborate the high quality of the AF2 model as a guide for experimental design and to interpret outcomes, not only confirm the active-site structural organization but also identify previously unobserved mechanistic contributions of catalytic and noncatalytic side chains.

Mitochondrial Dysfunction, Oxidative Stress, and Inter-Organ Miscommunications in T2D Progression

Type 2 diabetes (T2D) is a heterogenous disease, and conventionally, peripheral insulin resistance (IR) was thought to precede islet β-cell dysfunction, promoting progression from prediabetes to T2D. New evidence suggests that T2D-lean individuals experience early β-cell dysfunction without significant IR. Regardless of the primary event (i.e., IR vs. β-cell dysfunction) that contributes to dysglycemia, significant early-onset oxidative damage and mitochondrial dysfunction in multiple metabolic tissues may be a driver of T2D onset and progression. Oxidative stress, defined as the generation of reactive oxygen species (ROS), is mediated by hyperglycemia alone or in combination with lipids. Physiological oxidative stress promotes inter-tissue communication, while pathological oxidative stress promotes inter-tissue mis-communication, and new evidence suggests that this is mediated via extracellular vesicles (EVs), including mitochondria containing EVs. Under metabolic-related stress conditions, EV-mediated cross-talk between β-cells and skeletal muscle likely trigger mitochondrial anomalies leading to prediabetes and T2D. This article reviews the underlying molecular mechanisms in ROS-related pathogenesis of prediabetes, including mitophagy and mitochondrial dynamics due to oxidative stress. Further, this review will describe the potential of various therapeutic avenues for attenuating oxidative damage, reversing prediabetes and preventing progression to T2D.

A bioengineered artificial interstitium supports long-term islet xenograft survival in nonhuman primates without immunosuppression

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

EZH2 inhibitors promote β-like cell regeneration in young and adult type 1 diabetes donors

β-cells are a type of endocrine cell found in pancreatic islets that synthesize, store and release insulin. In type 1 diabetes (T1D), T-cells of the immune system selectively destroy the insulin-producing β-cells. Destruction of these cells leads to a lifelong dependence on exogenous insulin administration for survival. Consequently, there is an urgent need to identify novel therapies that stimulate β-cell growth and induce β-cell function. We and others have shown that pancreatic ductal progenitor cells are a promising source for regenerating β-cells for T1D owing to their inherent differentiation capacity. Default transcriptional suppression is refractory to exocrine reaction and tightly controls the regenerative potential by the EZH2 methyltransferase. In the present study, we show that transient stimulation of exocrine cells, derived from juvenile and adult T1D donors to the FDA-approved EZH2 inhibitors GSK126 and Tazemetostat (Taz) influence a phenotypic shift towards a β-like cell identity. The transition from repressed to permissive chromatin states are dependent on bivalent H3K27me3 and H3K4me3 chromatin modification. Targeting EZH2 is fundamental to β-cell regenerative potential. Reprogrammed pancreatic ductal cells exhibit insulin production and secretion in response to a physiological glucose challenge ex vivo. These pre-clinical studies underscore the potential of small molecule inhibitors as novel modulators of ductal progenitor differentiation and a promising new approach for the restoration of β-like cell function.

Dynamic-Covalent Crosslinking of Benzenetricarboxamide-Phenylboronate Conjugates

In an effort to augment the function of supramolecular biomaterials, recent efforts have explored the creation of hybrid materials that couple supramolecular and covalent components. Here, the benzenetricarboxamide (BTA) supramolecular polymer motif is modified to present a phenylboronic acid (PBA) in order to promote the crosslinking of 1D BTA stacks by PBA-diol dynamic-covalent bonds through the addition of a multi-arm diol-bearing crosslinker. Interestingly, the combination of these two motifs serves to frustrate the resulting assembly process, yielding hydrogels with worse mechanical properties than those prepared without the multi-arm diol crosslinker. Both systems with and without the crosslinker do, however, respond to the presence of a physiological level of glucose with a reduction in their mechanical integrity; repulsive electrostatic interactions in the BTA stacks occur in both cases upon glucose binding, with added competition from glucose with PBA-diol bonds amplifying glucose response in the hybrid material. Accordingly, the present results point to an unexpected outcome of reduced hydrogel mechanics, yet increased glucose response, when two disparate dynamic motifs of BTA supramolecular polymerization and PBA-diol crosslinking are combined, offering a vision for future preparation of glucose-responsive supramolecular biomaterials.

OGTT Metrics Surpass Continuous Glucose Monitoring Data for T1D Prediction in Multiple-Autoantibody-Positive Individuals

CONTEXT

The value of continuous glucose monitoring (CGM) for monitoring autoantibody (AAB)-positive individuals in clinical trials for progression of type 1 diabetes (T1D) is unknown.

OBJECTIVE

Compare CGM with oral glucose tolerance test (OGTT)-based metrics in prediction of T1D.

METHODS

At academic centers, OGTT and CGM data from multiple-AAB relatives were evaluated for associations with T1D diagnosis. Participants were multiple-AAB-positive individuals in a TrialNet Pathway to Prevention (TN01) CGM ancillary study (n = 93). The intervention was CGM for 1 week at baseline, 6 months, and 12 months. Receiver operating characteristic (ROC) curves of CGM and OGTT metrics for prediction of T1D were analyzed.

RESULTS

Five of 7 OGTT metrics and 29/48 CGM metrics but not HbA1c differed between those who subsequently did or did not develop T1D. ROC area under the curve (AUC) of individual CGM values ranged from 50% to 69% and increased when adjusted for age and AABs. However, the highest-ranking metrics were derived from OGTT: 4/7 with AUC ∼80%. Compared with adjusted multivariable models using CGM data, OGTT-derived variables, Index60 and DPTRS (Diabetes Prevention Trial-Type 1 Risk Score), had higher discriminative ability (higher ROC AUC and positive predictive value with similar negative predictive value).

CONCLUSION

Every 6-month CGM measures in multiple-AAB-positive individuals are predictive of subsequent T1D, but less so than OGTT-derived variables. CGM may have feasibility advantages and be useful in some settings. However, our data suggest there is insufficient evidence to replace OGTT measures with CGM in the context of clinical trials.

Tracking DNA-based antigen-specific T cell receptors during progression to type 1 diabetes

T cells targeting self-proteins are important mediators in autoimmune diseases. T cells express unique cell-surface receptors (TCRs) that recognize peptides presented by major histocompatibility molecules. TCRs have been identified from blood and pancreatic islets of individuals with type 1 diabetes (T1D). Here, we tracked ~1700 known antigen-specific TCR sequences, islet antigen or viral reactive, in bulk TCRβ sequencing from longitudinal blood DNA samples in at-risk cases who progressed to T1D, age/sex/human leukocyte antigen-matched controls, and a new-onset T1D cohort. Shared and frequent antigen-specific TCRβ sequences were identified in all three cohorts, and viral sequences were present across all ages. Islet sequences had different patterns of accumulation based upon antigen specificity in the at-risk cases. Furthermore, 73 islet-antigen TCRβ sequences were present in higher frequencies and numbers in T1D samples relative to controls. The total number of these disease-associated TCRβ sequences inversely correlated with age at clinical diagnosis, indicating the potential to use disease-relevant TCR sequences as biomarkers in autoimmune disorders.

Population Pharmacokinetic Model of N-Acetylcysteine During Periods of Recurrent Hypoglycemia in Healthy Volunteers

Recurrent hypoglycemia leads to impaired awareness of hypoglycemia where the blood glucose threshold that elicits the counterregulatory response is lowered. Hypoglycemia-induced oxidative stress is hypothesized to contribute to impaired awareness of hypoglycemia development and hypoglycemia-associated autonomic failure. Our group conducted a randomized, double-blinded, placebo-controlled, crossover study in healthy individuals undergoing experimentally induced recurrent hypoglycemia to evaluate the impact of intravenous N-acetylcysteine (NAC) during experimental hypoglycemia to preserve the counterregulatory response to subsequent hypoglycemia. The work presented herein aimed to characterize the NAC pharmacokinetics and its effects on oxidative stress. Whole blood and plasma samples were collected at specified time points during separate NAC and placebo infusions from 10 healthy volunteers. Samples were analyzed for NAC, cysteine, and glutathione (GSH) concentrations. A 2-compartment population NAC pharmacokinetic model was developed. Estimates for central compartment clearance and volume of distribution were 19.8 L/h, and 12.2 L, respectively, for a 70-kg person. Peripheral compartment clearance and volume of distribution estimates were 34.9 L/h and 13.1 L, respectively, for a 70-kg person. The PK parameters estimated here were different from those reported in the literature, suggesting a higher NAC clearance during hypoglycemic episodes. NAC leads to a significant increase in circulating cysteine concentration in a NAC concentration-dependent manner, suggesting rapid biotransformation. A transient decrease in plasma GSH was observed, supporting the hypothesis that NAC can act as a reducing agent displacing glutathione from the disulfide bond allowing for increased clearance and/or distribution of GSH.

Clinical implications of ADHD, ASD, and their co-occurrence in early adulthood-the prospective ABIS-study

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are childhood-onset disorders associated with functional and psychosocial impairments that may persist into adulthood, leading to serious personal and societal costs.

OBJECTIVE

This study aimed to examine the socio-economic difficulties, physical and mental comorbidities, and psycho-social vulnerabilities associated with ADHD, ASD, and their co-occurrence among young adults.

METHODS

16 365 families with children born 1997-1999, were involved in the prospective population-based ABIS study (All Babies in Southeast Sweden). A total of 6 233 ABIS young adults answered the questionnaire at the 17-19-year follow-up and were included in this case-control study. Diagnoses of ADHD and ASD from birth up to 17 years of age were obtained from the Swedish National Diagnosis Register. N=182 individuals received a single diagnosis of ADHD, n=78 of ASD, and n=51 received both diagnoses and were considered the co-occurrence group. Multiple multinomial logistic regression analyses were performed.

RESULTS

In the univariate analyses all three conditions were significantly associated with concentration difficulties, worse health quality, lower socio-economic status, lower faith in the future, less control over life, and lower social support. In the adjusted analyses, individuals with ADHD were almost three-times more likely to have less money compared with their friends (aOR 2.86; p < .001), experienced worse sleep quality (aOR 1.50; p = .043) and concentration difficulties (aOR 1.96; p < .001). ASD group were two-fold more likely to experience concentration difficulties (aOR 2.35; p = .002) and tended not to have faith in the future (aOR .63; p = .055), however, showed lesser risk-taking bahaviours (aOR .40; p < .001). Finally, the co-occurrence was significantly associated with unemployment (aOR 2.64; p = .007) and tended to have a higher risk of autoimmune disorders (aOR 2.41; p = .051), however, showed a 51% lower risk of stomach pain (aOR .49; p = .030).

CONCLUSIONS

All these conditions significantly deteriorated several areas of life. ADHD/ASD co-occurrence is a heavy burden for health associated with several psychosocial vulnerabilities, that shared a similar morbidity pattern with ADHD although showed less risk cognitive and behavioral profile, similar to the ASD group. Long-term follow-up and support for individuals with these conditions over the life course are crucial.

RANKL/RANK is required for cytokine-induced beta cell death; osteoprotegerin, a RANKL inhibitor, reverses rodent type 1 diabetes

Treatment for type 1 diabetes (T1D) requires stimulation of functional β cell regeneration and survival under stress. Previously, we showed that inhibition of the RANKL/RANK [receptor activator of nuclear factor kappa Β (NF-κB) ligand] pathway, by osteoprotegerin and the anti-osteoporotic drug denosumab, induces rodent and human β cell proliferation. We demonstrate that the RANK pathway mediates cytokine-induced rodent and human β cell death through RANK-TRAF6 interaction and induction of NF-κB activation. Osteoprotegerin and denosumab protected β cells against this cytotoxicity. In human immune cells, osteoprotegerin and denosumab reduce proinflammatory cytokines in activated T-cells by inhibiting RANKL-induced activation of monocytes. In vivo, osteoprotegerin reversed recent-onset T1D in nonobese diabetic/Ltj mice, reduced insulitis, improved glucose homeostasis, and increased plasma insulin, β cell proliferation, and mass in these mice. Serum from T1D subjects induced human β cell death and dysfunction, but not α cell death. Osteoprotegerin and denosumab reduced T1D serum-induced β cell cytotoxicity and dysfunction. Inhibiting RANKL/RANK could have therapeutic potential.

Immunological Phenotyping of Mice with a Point Mutation in Cdk4

Cyclin-dependent kinases (CDKs) play a crucial role in regulation of the mammalian cell cycle. CDK4 and CDK6 control the G1/S restriction checkpoint through their ability to associate with cyclin D proteins in response to growth factor signals. CDK4 deficiency in mice gives rise to a range of endocrine-specific phenotypes including diabetes, infertility, dwarfism, and atrophy of the anterior pituitary. Although CDK6 deficiency can cause thymic atrophy due to a block in the double-negative (DN) to double-positive (DP) stage of T cell development, there are no overt defects in immune cell development reported for CDK4-deficient mice. Here, we examined the impact of a novel N-ethyl-N-nitrosourea-induced point mutation in the gene encoding CDK4 on immune cell development. Mutant mice (Cdk4wnch/wnch) showed normal development and differentiation of major immune cell subsets in the thymus and spleen. Moreover, T cells from Cdk4wnch/wnch mice exhibited normal cytokine production in response to in vitro stimulation. However, analysis of the mixed bone marrow chimeras revealed that Cdk4wnch/wnch-derived T cell subsets and NK cells are at a competitive disadvantage compared to Cdk4+/+-derived cells in the thymus and periphery of recipients. These results suggest a possible role for the CDK4wnch mutation in the development of some immune cells, which only becomes apparent when the Cdk4wnch/wnch mutant cells are in direct competition with wild-type immune cells in the mixed bone marrow chimera.

Stem Cell-Derived Islet Transplantation in Patients With Type 2 Diabetes: Can Diabetes Subtypes Guide Implementation?

Historically, only patients with brittle diabetes or severe recurrent hypoglycemia have been considered for islet transplantation (ITx). This population has been selected to optimize the risk-benefit profile, considering risks of long-term immunosuppression and limited organ supply. However, with the advent of stem cell (SC)-derived ITx and the potential for immunosuppression-free ITx, consideration of a broader recipient cohort may soon be justified. Simultaneously, the classical categorization of diabetes is being challenged by growing evidence in support of a clustering of disease subtypes that can be better categorized by the All New Diabetics in Scania (ANDIS) classification system. Using the ANDIS classification, 5 subtypes of diabetes have been described, each with unique causes and consequences. We evaluate consideration for ITx in the context of this broader patient population and the new classification of diabetes subtypes. In this review, we evaluate considerations for ITx based on novel diabetes subtypes, including their limitations, and we elaborate on unique transplant features that should now be considered to enable ITx in these "unconventional" patient cohorts. Based on evidence from those receiving whole pancreas transplant and our more than 20-year experience with ITx, we offer recommendations and potential research avenues to justify implementation of SC-derived ITx in broader populations of patients with all types of diabetes.

Limited Hyperoxia-Induced Proliferative Retinopathy (LHIPR) as a Model of Retinal Fibrosis, Angiogenesis, and Inflammation

The progression to fibrosis and traction in retinopathy of prematurity (ROP) and other ischemic retinopathies remains an important clinical and surgical challenge, necessitating a comprehensive understanding of its pathogenesis. Fibrosis is an unbalanced deposition of extracellular matrix components responsible for scar tissue formation with consequent tissue and organ impairment. Together with retinal traction, it is among the main causes of retinal detachment and vision loss. We capitalize on the Limited Hyperoxia Induced Retinopathy (LHIPR) model, as it reflects the more advanced pathological phenotypes seen in ROP and other ischemic retinopathies. To model LHIPR, we exposed wild-type C57Bl/6J mouse pups to 65% oxygen from P0 to P7. Then, the pups were returned to room air to recover until later endpoints. We performed histological and molecular analysis to evaluate fibrosis progression, angiogenesis, and inflammation at several time points, from 1.5 months to 9 months. In addition, we performed in vivo retinal imaging by optical coherence tomography (OCT) or OCT Angiography (OCTA) to follow the fibrovascular progression in vivo. Although the retinal morphology was relatively preserved, we found a progressive increase in preretinal fibrogenesis over time, up to 9 months of age. We also detected blood vessels in the preretinal space as well as an active inflammatory process, altogether mimicking advanced preretinal fibrovascular disease in humans.

Inferring regulators of cell identity in the human adult pancreas

Cellular identity during development is under the control of transcription factors that form gene regulatory networks. However, the transcription factors and gene regulatory networks underlying cellular identity in the human adult pancreas remain largely unexplored. Here, we integrate multiple single-cell RNA-sequencing datasets of the human adult pancreas, totaling 7393 cells, and comprehensively reconstruct gene regulatory networks. We show that a network of 142 transcription factors forms distinct regulatory modules that characterize pancreatic cell types. We present evidence that our approach identifies regulators of cell identity and cell states in the human adult pancreas. We predict that HEYL, BHLHE41 and JUND are active in acinar, beta and alpha cells, respectively, and show that these proteins are present in the human adult pancreas as well as in human induced pluripotent stem cell (hiPSC)-derived islet cells. Using single-cell transcriptomics, we found that JUND represses beta cell genes in hiPSC-alpha cells. BHLHE41 depletion induced apoptosis in primary pancreatic islets. The comprehensive gene regulatory network atlas can be explored interactively online. We anticipate our analysis to be the starting point for a more sophisticated dissection of how transcription factors regulate cell identity and cell states in the human adult pancreas.

Children diagnosed with presymptomatic type 1 diabetes through public health screening have milder diabetes at clinical manifestation

AIMS/HYPOTHESIS

We aimed to determine whether disease severity was reduced at onset of clinical (stage 3) type 1 diabetes in children previously diagnosed with presymptomatic type 1 diabetes in a population-based screening programme for islet autoantibodies.

METHODS

Clinical data obtained at diagnosis of stage 3 type 1 diabetes were evaluated in 128 children previously diagnosed with presymptomatic early-stage type 1 diabetes between 2015 and 2022 in the Fr1da study and compared with data from 736 children diagnosed with incident type 1 diabetes between 2009 and 2018 at a similar age in the DiMelli study without prior screening.

RESULTS

At the diagnosis of stage 3 type 1 diabetes, children with a prior early-stage diagnosis had lower median HbA1c (51 mmol/mol vs 91 mmol/mol [6.8% vs 10.5%], p<0.001), lower median fasting glucose (5.3 mmol/l vs 7.2 mmol/l, p<0.05) and higher median fasting C-peptide (0.21 nmol/l vs 0.10 nmol/l, p<0.001) compared with children without previous early-stage diagnosis. Fewer participants with prior early-stage diagnosis had ketonuria (22.2% vs 78.4%, p<0.001) or required insulin treatment (72.3% vs 98.1%, p<0.05) and only 2.5% presented with diabetic ketoacidosis at diagnosis of stage 3 type 1 diabetes. Outcomes in children with a prior early-stage diagnosis were not associated with a family history of type 1 diabetes or diagnosis during the COVID-19 pandemic. A milder clinical presentation was observed in children who participated in education and monitoring after early-stage diagnosis.

CONCLUSIONS/INTERPRETATION

Diagnosis of presymptomatic type 1 diabetes in children followed by education and monitoring improved clinical presentation at the onset of stage 3 type 1 diabetes.

Long-Term Survival and Induction of Operational Tolerance to Murine Islet Allografts by Co-Transplanting Cyclosporine A Microparticles and CTLA4-Ig

One strategy to prevent islet rejection is to create a favorable immune-protective local environment at the transplant site. Herein, we utilize localized cyclosporine A (CsA) delivery to islet grafts via poly(lactic-co-glycolic acid) (PLGA) microparticles to attenuate allograft rejection. CsA-eluting PLGA microparticles were prepared using a single emulsion (oil-in-water) solvent evaporation technique. CsA microparticles alone significantly delayed islet allograft rejection compared to islets alone (p < 0.05). Over 50% (6/11) of recipients receiving CsA microparticles and short-term cytotoxic T lymphocyte-associated antigen 4-Ig (CTLA4-Ig) therapy displayed prolonged allograft survival for 214 days, compared to 25% (2/8) receiving CTLA4-Ig alone. CsA microparticles alone and CsA microparticles + CTLA4-Ig islet allografts exhibited reduced T-cell (CD4+ and CD8+ cells, p < 0.001) and macrophage (CD68+ cells, p < 0.001) infiltration compared to islets alone. We observed the reduced mRNA expression of proinflammatory cytokines (IL-6, IL-10, INF-γ, and TNF-α; p < 0.05) and chemokines (CCL2, CCL5, CCL22, and CXCL10; p < 0.05) in CsA microparticles + CTLA4-Ig allografts compared to islets alone. Long-term islet allografts contained insulin+ and intra-graft FoxP3+ T regulatory cells. The rapid rejection of third-party skin grafts (C3H) in islet allograft recipients suggests that CsA microparticles + CTLA4-Ig therapy induced operational tolerance. This study demonstrates that localized CsA drug delivery plus short-course systemic immunosuppression promotes an immune protective transplant niche for allogeneic islets.

GABA and Combined GABA with GAD65-Alum Treatment Alters Th1 Cytokine Responses of PBMCs from Children with Recent-Onset Type 1 Diabetes

Type 1 diabetes (T1D) is an autoimmune disease culminating in the destruction of insulin-producing pancreatic cells. There is a need for the development of novel antigen-specific strategies to delay cell destruction, including combinatorial strategies that do not elicit systemic immunosuppression. Gamma-aminobutyric acid (GABA) is expressed by immune cells, β-cells, and gut bacteria and is immunomodulatory. Glutamic-acid decarboxylase 65 (GAD65), which catalyzes GABA from glutamate, is a T1D autoantigen. To test the efficacy of combinatorial GABA treatment with or without GAD65-immunization to dampen autoimmune responses, we enrolled recent-onset children with T1D in a one-year clinical trial (ClinicalTrials.gov NCT02002130) and examined T cell responses. We isolated peripheral blood mononuclear cells and evaluated cytokine responses following polyclonal activation and GAD65 rechallenge. Both GABA alone and GABA/GAD65-alum treatment inhibited Th1 cytokine responses over the 12-month study with both polyclonal and GAD65 restimulation. We also investigated whether patients with HLA-DR3-DQ2 and HLA-DR4-DQ8, the two highest-risk human leukocyte antigen (HLA) haplotypes in T1D, exhibited differences in response to GABA alone and GABA/GAD65-alum. HLA-DR4-DQ8 patients possessed a Th1-skewed response compared to HLA-DR3-DQ2 patients. We show that GABA and GABA/GAD65-alum present an attractive immunomodulatory treatment for children with T1D and that HLA haplotypes should be considered.

The Vitamin D Metabolite Ratio (VMR) is a Biomarker of Vitamin D Status That is Not Affected by Acute Changes in Vitamin D Binding Protein

BACKGROUND

25-hydroxyvitamin D[25(OH)D] may be a poor marker of vitamin D status due to variability in levels of vitamin D binding protein (VDBP). The vitamin D metabolite ratio (VMR) is the ratio of 24,25-dihydroxyvitamin D[24,25(OH)2D3] to 25(OH)D3 and has been postulated to reflect vitamin D sufficiency independent of variability in VDBP. Therapeutic plasma exchange (TPE) is a procedure that removes plasma, including VDBP, and may lower bound vitamin D metabolite concentrations. Effects of TPE on the VMR are unknown.

METHODS

We measured 25(OH)D, free 25(OH)D, 1,25-dihydroxyvitamin D[1,25(OH)2D], 24,25(OH)2D3, and VDBP in persons undergoing TPE, before and after treatment. We used paired t-tests to assess changes in these biomarkers during a TPE procedure.

RESULTS

Study participants (n = 45) had a mean age of 55 ± 16 years; 67% were female; and 76% were white. Compared to pretreatment concentrations, TPE caused a significant decrease in total VDBP by 65% (95%CI 60,70%), as well as all the vitamin D metabolites-25(OH)D by 66% (60%,74%), free 25(OH)D by 31% (24%,39%), 24,25(OH)2D3 by 66% (55%,78%) and 1,25(OH)2D by 68% (60%,76%). In contrast, there was no significant change in the VMR before and after a single TPE treatment, with an observed mean 7% (-3%, 17%) change in VMR.

CONCLUSIONS

Changes in VDBP concentration across TPE parallel changes in 25(OH)D, 1,25(OH)2D, and 24,25(OH)2D3, suggesting that concentrations of these metabolites reflect underlying VDBP concentrations. The VMR is stable across a TPE session despite a 65% reduction in VDBP. These findings suggest that the VMR is a marker of vitamin D status independent of VDBP levels.

Single-nucleus multi-omics of human stem cell-derived islets identifies deficiencies in lineage specification

Insulin-producing β cells created from human pluripotent stem cells have potential as a therapy for insulin-dependent diabetes, but human pluripotent stem cell-derived islets (SC-islets) still differ from their in vivo counterparts. To better understand the state of cell types within SC-islets and identify lineage specification deficiencies, we used single-nucleus multi-omic sequencing to analyse chromatin accessibility and transcriptional profiles of SC-islets and primary human islets. Here we provide an analysis that enabled the derivation of gene lists and activity for identifying each SC-islet cell type compared with primary islets. Within SC-islets, we found that the difference between β cells and awry enterochromaffin-like cells is a gradient of cell states rather than a stark difference in identity. Furthermore, transplantation of SC-islets in vivo improved cellular identities overtime, while long-term in vitro culture did not. Collectively, our results highlight the importance of chromatin and transcriptional landscapes during islet cell specification and maturation.

UBASH3A Interacts with PTPN22 to Regulate IL2 Expression and Risk for Type 1 Diabetes

UBASH3A is a negative regulator of T cell activation and IL-2 production and plays key roles in autoimmunity. Although previous studies revealed the individual effects of UBASH3A on risk for type 1 diabetes (T1D; a common autoimmune disease), the relationship of UBASH3A with other T1D risk factors remains largely unknown. Given that another well-known T1D risk factor, PTPN22, also inhibits T cell activation and IL-2 production, we investigated the relationship between UBASH3A and PTPN22. We found that UBASH3A, via its Src homology 3 (SH3) domain, physically interacts with PTPN22 in T cells, and that this interaction is not altered by the T1D risk coding variant rs2476601 in PTPN22. Furthermore, our analysis of RNA-seq data from T1D cases showed that the amounts of UBASH3A and PTPN22 transcripts exert a cooperative effect on IL2 expression in human primary CD8⁺ T cells. Finally, our genetic association analyses revealed that two independent T1D risk variants, rs11203203 in UBASH3A and rs2476601 in PTPN22, interact statistically, jointly affecting risk for T1D. In summary, our study reveals novel interactions, both biochemical and statistical, between two independent T1D risk loci, and suggests how these interactions may affect T cell function and increase risk for T1D.

NET Proteome in Established Type 1 Diabetes Is Enriched in Metabolic Proteins

BACKGROUND AND AIMS

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by a T-cell-mediated destruction of the pancreatic insulin-producing beta cells. A growing body of evidence suggests that abnormalities in neutrophils and neutrophil extracellular trap (NET) formation (NETosis) are associated with T1D pathophysiology. However, little information is available on whether these changes are primary neutrophil defects or related to the environmental signals encountered during active disease.

METHODS

In the present work, the NET proteome (NETome) of phorbol 12-myristate 13-acetate (PMA)- and ionomycin-stimulated neutrophils from people with established T1D compared to healthy controls (HC) was studied by proteomic analysis.

RESULTS

Levels of NETosis, in addition to plasma levels of pro-inflammatory cytokines and NET markers, were comparable between T1D and HC subjects. However, the T1D NETome was distinct from that of HC in response to both stimuli. Quantitative analysis revealed that the T1D NETome was enriched in proteins belonging to metabolic pathways (i.e., phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase, and UTP-glucose-1-phosphate uridylyltransferase). Complementary metabolic profiling revealed that the rate of extracellular acidification, an approximate measure for glycolysis, and mitochondrial respiration were similar between T1D and HC neutrophils in response to both stimuli.

CONCLUSION

The NETome of people with established T1D was enriched in metabolic proteins without an apparent alteration in the bio-energetic profile or dysregulated NETosis. This may reflect an adaptation mechanism employed by activated T1D neutrophils to avoid impaired glycolysis and consequently excessive or suboptimal NETosis, pivotal in innate immune defence and the resolution of inflammation.

Presence of immunogenic alternatively spliced insulin gene product in human pancreatic delta cells

AIMS/HYPOTHESIS

Transcriptome analyses revealed insulin-gene-derived transcripts in non-beta endocrine islet cells. We studied alternative splicing of human INS mRNA in pancreatic islets.

METHODS

Alternative splicing of insulin pre-mRNA was determined by PCR analysis performed on human islet RNA and single-cell RNA-seq analysis. Antisera were generated to detect insulin variants in human pancreatic tissue using immunohistochemistry, electron microscopy and single-cell western blot to confirm the expression of insulin variants. Cytotoxic T lymphocyte (CTL) activation was determined by MIP-1β release.

RESULTS

We identified an alternatively spliced INS product. This variant encodes the complete insulin signal peptide and B chain and an alternative C-terminus that largely overlaps with a previously identified defective ribosomal product of INS. Immunohistochemical analysis revealed that the translation product of this INS-derived splice transcript was detectable in somatostatin-producing delta cells but not in beta cells; this was confirmed by light and electron microscopy. Expression of this alternatively spliced INS product activated preproinsulin-specific CTLs in vitro. The exclusive presence of this alternatively spliced INS product in delta cells may be explained by its clearance from beta cells by insulin-degrading enzyme capturing its insulin B chain fragment and a lack of insulin-degrading enzyme expression in delta cells.

CONCLUSIONS/INTERPRETATION

Our data demonstrate that delta cells can express an INS product derived from alternative splicing, containing both the diabetogenic insulin signal peptide and B chain, in their secretory granules. We propose that this alternative INS product may play a role in islet autoimmunity and pathology, as well as endocrine or paracrine function or islet development and endocrine destiny, and transdifferentiation between endocrine cells. INS promoter activity is not confined to beta cells and should be used with care when assigning beta cell identity and selectivity.

DATA AVAILABILITY

The full EM dataset is available via www.nanotomy.org (for review: http://www.nanotomy.org/OA/Tienhoven2021SUB/6126-368/ ). Single-cell RNA-seq data was made available by Segerstolpe et al [13] and can be found at https://sandberglab.se/pancreas . The RNA and protein sequence of INS-splice was uploaded to GenBank (BankIt2546444 INS-splice OM489474).

Nutrient regulation of the islet epigenome controls adaptive insulin secretion

Adaptation of the islet β cell insulin-secretory response to changing insulin demand is critical for blood glucose homeostasis, yet the mechanisms underlying this adaptation are unknown. Here, we have shown that nutrient-stimulated histone acetylation plays a key role in adapting insulin secretion through regulation of genes involved in β cell nutrient sensing and metabolism. Nutrient regulation of the epigenome occurred at sites occupied by the chromatin-modifying enzyme lysine-specific demethylase 1 (Lsd1) in islets. β Cell-specific deletion of Lsd1 led to insulin hypersecretion, aberrant expression of nutrient-response genes, and histone hyperacetylation. Islets from mice adapted to chronically increased insulin demand exhibited shared epigenetic and transcriptional changes. Moreover, we found that genetic variants associated with type 2 diabetes were enriched at LSD1-bound sites in human islets, suggesting that interpretation of nutrient signals is genetically determined and clinically relevant. Overall, these studies revealed that adaptive insulin secretion involves Lsd1-mediated coupling of nutrient state to regulation of the islet epigenome.

Experiences and Attitudes of Parents Reducing Carbohydrate Intake in the Management of Their Child’s Type 1 Diabetes: A Qualitative Study

Reducing carbohydrate (CHO) intake is being used as an approach to manage type 1 diabetes (T1D) in children. This study aimed to investigate the experiences and attitudes of parents of children with T1D who are reducing CHO intake to help manage blood glucose levels (BGLs). Semi-structured interviews were conducted with the parents of children with T1D for >1 year who reported implementing a low CHO approach to manage BGLs. Data were analysed using a constant comparative analysis approach. Participants (n = 14) were parents of children (6.6 ± 2.0 years) with T1D in Western Australia. All parents reported different methods of CHO restriction and all perceived that benefits outweighed challenges. Parents reported feeling less worried, had improved sleep and felt their child was safer when using a low CHO approach due to more stable BGLs. Reported challenges included: increased cost and time spent preparing food; perceived judgement from others; and child dissatisfaction with restricted food choices. Parents reported accessing information and support through social media networks. Parents reported a desire for more research into this approach. Understanding the promoters and barriers for this dietary approach may inform strategies to better engage and support families with approaches that align with current evidence while considering their concerns around safety and hyperglycaemia.

Risk of relapse of ANCA-associated vasculitis among patients homozygous for the proteinase 3 gene Val119Ile polymorphism

BACKGROUND

The frequency of proteinase 3 gene (PRTN3) polymorphisms in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is not fully characterised. We hypothesise that the presence of a PRTN3 gene polymorphism (single nucleotide polymorphism (SNP) rs351111) is relevant for clinical outcomes.

METHODS

DNA variant calling for SNP rs351111 (chr.19:844020, c.355G>A) in PRTN3 gene assessed the allelic frequency in patients with PR3-AAV included in the Rituximab in ANCA-Associated Vasculitis trial. This was followed by RNA-seq variant calling to characterise the mRNA expression. We compared clinical outcomes between patients homozygous for PRTN3-Ile119 or PRTN3-Val119.

RESULTS

Whole blood samples for DNA calling were available in 188 patients. 75 patients with PR3-AAV had the allelic variant: 62 heterozygous PRTN3-Val119Ile and 13 homozygous for PRTN3-Ile119. RNA-seq was available for 89 patients and mRNA corresponding to the allelic variant was found in 32 patients with PR3-AAV: 25 heterozygous PRTN3-Val119Ile and 7 homozygous for PRTN3-Ile119. The agreement between the DNA calling results and mRNA expression of the 86 patients analysed by both methods was 100%. We compared the clinical outcomes of 64 patients with PR3-AAV: 51 homozygous for PRTN3-Val119 and 13 homozygous for PRTN3-Ile119. The frequency of severe flares at 18 months in homozygous PRTN3-Ile119 was significantly higher when compared with homozygous PRTN3-Val119 (46.2% vs 19.6%, p=0.048). Multivariate analysis identified homozygous PR3-Ile119 as main predictor of severe relapse (HR 4.67, 95% CI 1.16 to 18.86, p=0.030).

CONCLUSION

In patients with PR3-AAV, homozygosity for PRTN3-Val119Ile polymorphism appears associated with higher frequency of severe relapse. Further studies are necessary to better understand the association of this observation with the risk of severe relapse.

Longitudinal consumption of fruits and vegetables and risk of asthma by 5 years of age

BACKGROUND

Fruit and vegetable consumption has been linked to a decreased risk of asthma, but prospective evidence on longitudinal consumption in childhood is scarce. We aimed to investigate the association between fruit and vegetable consumption in childhood and the risk of asthma by the age of 5 years, and to explore the role of processing of fruits and vegetables in the Finnish Type 1 Diabetes Prediction and Prevention Allergy Study.

METHODS

Child's food consumption was assessed by 3-day food records completed at the age of 3 and 6 months, and 1, 2, 3, 4, and 5 years, and asthma and allergies by a validated modified version of the ISAAC questionnaire at the age of 5 years. Consumption of processed and unprocessed fruits and vegetables was calculated. Joint models with a current value association structure for longitudinal and time-to-event data were used for statistical analyses.

RESULTS

Of the 3053 children, 184 (6%) developed asthma by the age of 5 years. The risk of asthma was not associated with the consumption of all fruits and vegetables together (HR 1.00, 95%CI 0.99-1.01 per consumption of 1 g/MJ, adjusted for energy and other covariates), or with most subgroups. Weak inverse associations were seen between all leafy vegetables and asthma (HR = 0.87, 0.77-0.99), and unprocessed vegetables and nonatopic asthma (HR = 0.90, 95% CI 0.81-0.98).

CONCLUSION

Total consumption of fruits and vegetables in childhood was not associated with the development of asthma by the age of 5 years. Weak inverse associations found for vegetables need to be confirmed or rejected in future studies.

Spectrum of Clinical Presentations, Imaging Findings, and HLA Types in Immune Checkpoint Inhibitor-Induced Hypophysitis

Context

Hypophysitis is a known immune-related adverse event (irAE) of immune checkpoint inhibitors (CPIs), commonly associated with CTLA-4 inhibitors and less often with PD-1/PD-L1 inhibitors.

Objective

We aimed to determine clinical, imaging, and HLA characteristics of CPI-induced hypophysitis (CPI-hypophysitis).

Methods

We examined the clinical and biochemical characteristics, magnetic resonance imaging (MRI) of the pituitary, and association with HLA type in patients with CPI-hypophysitis.

Results

Forty-nine patients were identified. Mean age was 61.3 years, 61.2% were men, 81.6% were Caucasian, 38.8% had melanoma, and 44.5% received PD-1/PD-L1 inhibitor monotherapy while the remainder received CTLA-4 inhibitor monotherapy or CTLA-4/PD-1 inhibitor combination therapy. A comparison of CTLA-4 inhibitor exposure vs PD-1/PD-L1 inhibitor monotherapy revealed faster time to CPI-hypophysitis (median 84 vs 185 days, P < .01) and abnormal pituitary appearance on MRI (odds ratio 7.00, P = .03). We observed effect modification by sex in the association between CPI type and time to CPI-hypophysitis. In particular, anti-CTLA-4 exposed men had a shorter time to onset than women. MRI changes of the pituitary were most common at the time of hypophysitis diagnosis (55.6% enlarged, 37.0% normal, 7.4% empty or partially empty) but persisted in follow-up (23.8% enlarged, 57.1% normal, 19.1% empty or partially empty). HLA typing was done on 55 subjects; HLA type DQ0602 was over-represented in CPI-hypophysitis relative to the Caucasian American population (39.4% vs 21.5%, P = 0.01) and CPI population.

Conclusion

The association of CPI-hypophysitis with HLA DQ0602 suggests a genetic risk for its development. The clinical phenotype of hypophysitis appears heterogenous, with differences in timing of onset, changes in thyroid function tests, MRI changes, and possibly sex related to CPI type. These factors may play an important role in our mechanistic understanding of CPI-hypophysitis.

Artificial Intelligence Based Analysis of Corneal Confocal Microscopy Images for Diagnosing Peripheral Neuropathy: A Binary Classification Model

Diabetic peripheral neuropathy (DPN) is the leading cause of neuropathy worldwide resulting in excess morbidity and mortality. We aimed to develop an artificial intelligence deep learning algorithm to classify the presence or absence of peripheral neuropathy (PN) in participants with diabetes or pre-diabetes using corneal confocal microscopy (CCM) images of the sub-basal nerve plexus. A modified ResNet-50 model was trained to perform the binary classification of PN (PN+) versus no PN (PN-) based on the Toronto consensus criteria. A dataset of 279 participants (149 PN-, 130 PN+) was used to train (n = 200), validate (n = 18), and test (n = 61) the algorithm, utilizing one image per participant. The dataset consisted of participants with type 1 diabetes (n = 88), type 2 diabetes (n = 141), and pre-diabetes (n = 50). The algorithm was evaluated using diagnostic performance metrics and attribution-based methods (gradient-weighted class activation mapping (Grad-CAM) and Guided Grad-CAM). In detecting PN+, the AI-based DLA achieved a sensitivity of 0.91 (95%CI: 0.79-1.0), a specificity of 0.93 (95%CI: 0.83-1.0), and an area under the curve (AUC) of 0.95 (95%CI: 0.83-0.99). Our deep learning algorithm demonstrates excellent results for the diagnosis of PN using CCM. A large-scale prospective real-world study is required to validate its diagnostic efficacy prior to implementation in screening and diagnostic programmes.

The relationship between islet autoantibody status and the genetic risk of type 1 diabetes in adult-onset type 1 diabetes

AIMS/HYPOTHESIS

The reason for the observed lower rate of islet autoantibody positivity in clinician-diagnosed adult-onset vs childhood-onset type 1 diabetes is not known. We aimed to explore this by assessing the genetic risk of type 1 diabetes in autoantibody-negative and -positive children and adults.

METHODS

We analysed GAD autoantibodies, insulinoma-2 antigen autoantibodies and zinc transporter-8 autoantibodies (ZnT8A) and measured type 1 diabetes genetic risk by genotyping 30 type 1 diabetes-associated variants at diagnosis in 1814 individuals with clinician-diagnosed type 1 diabetes (1112 adult-onset, 702 childhood-onset). We compared the overall type 1 diabetes genetic risk score (T1DGRS) and non-HLA and HLA (DR3-DQ2, DR4-DQ8 and DR15-DQ6) components with autoantibody status in those with adult-onset and childhood-onset diabetes. We also measured the T1DGRS in 1924 individuals with type 2 diabetes from the Wellcome Trust Case Control Consortium to represent non-autoimmune diabetes control participants.

RESULTS

The T1DGRS was similar in autoantibody-negative and autoantibody-positive clinician-diagnosed childhood-onset type 1 diabetes (mean [SD] 0.274 [0.034] vs 0.277 [0.026], p=0.4). In contrast, the T1DGRS in autoantibody-negative adult-onset type 1 diabetes was lower than that in autoantibody-positive adult-onset type 1 diabetes (mean [SD] 0.243 [0.036] vs 0.271 [0.026], p<0.0001) but higher than that in type 2 diabetes (mean [SD] 0.229 [0.034], p<0.0001). Autoantibody-negative adults were more likely to have the more protective HLA DR15-DQ6 genotype (15% vs 3%, p<0.0001), were less likely to have the high-risk HLA DR3-DQ2/DR4-DQ8 genotype (6% vs 19%, p<0.0001) and had a lower non-HLA T1DGRS (p<0.0001) than autoantibody-positive adults. In contrast to children, autoantibody-negative adults were more likely to be male (75% vs 59%), had a higher BMI (27 vs 24 kg/m²) and were less likely to have other autoimmune conditions (2% vs 10%) than autoantibody-positive adults (all p<0.0001). In both adults and children, type 1 diabetes genetic risk was unaffected by the number of autoantibodies (p>0.3). These findings, along with the identification of seven misclassified adults with monogenic diabetes among autoantibody-negative adults and the results of a sensitivity analysis with and without measurement of ZnT8A, suggest that the intermediate type 1 diabetes genetic risk in autoantibody-negative adults is more likely to be explained by the inclusion of misclassified non-autoimmune diabetes (estimated to represent 67% of all antibody-negative adults, 95% CI 61%, 73%) than by the presence of unmeasured autoantibodies or by a discrete form of diabetes. When these estimated individuals with non-autoimmune diabetes were adjusted for, the prevalence of autoantibody positivity in adult-onset type 1 diabetes was similar to that in children (93% vs 91%, p=0.4).

CONCLUSIONS/INTERPRETATION

The inclusion of non-autoimmune diabetes is the most likely explanation for the observed lower rate of autoantibody positivity in clinician-diagnosed adult-onset type 1 diabetes. Our data support the utility of islet autoantibody measurement in clinician-suspected adult-onset type 1 diabetes in routine clinical practice.

Milder loss of insulin-containing islets in individuals with type 1 diabetes and type 2 diabetes-associated TCF7L2 genetic variants

AIMS/HYPOTHESIS

TCF7L2 variants are the strongest genetic risk factor for type 2 diabetes. In individuals with type 1 diabetes, these variants are associated with a higher C-peptide AUC, a lower glucose AUC during an OGTT, single autoantibody positivity near diagnosis, particularly in individuals older than 12 years of age, and a lower frequency of type 1 diabetes-associated HLA genotypes. Based on initial observations from clinical cohorts, we tested the hypothesis that type 2 diabetes-predisposing TCF7L2 genetic variants are associated with a higher percentage of residual insulin-containing cells (ICI%) in pancreases of donors with type 1 diabetes, by examining genomic data and pancreatic tissue samples from the Network for Pancreatic Organ donors with Diabetes (nPOD) programme.

METHODS

We analysed nPOD donors with type 1 diabetes (n=110; mean±SD age at type 1 diabetes onset 12.2±7.9 years, mean±SD diabetes duration 15.3±13.7 years, 53% male, 80% non-Hispanic White, 12.7% African American, 7.3% Hispanic) using data pertaining to residual beta cell number; quantified islets containing insulin-positive beta cells in pancreatic tissue sections; and expressed these values as a percentage of the total number of islets from each donor (mean ± SD ICI% 9.8±21.5, range 0-92.2).

RESULTS

Donors with a high ICI% (≥5) (n=30; 27%) vs a low ICI% (<5) (n=80; 73%) were older at onset (15.3±6.9 vs 11.1±8 years, p=0.013), had a shorter diabetes duration at donor tissue procurement (7.0±7.4 vs 18.5±14.3 years, p<0.001), a higher African ancestry score (0.2±0.3 vs 0.1±0.2, p=0.043) and a lower European ancestry score (0.7±0.3 vs 0.9±0.3, p=0.023). After adjustment for age of onset (p=0.105), diabetes duration (p<0.001), BMI z score (p=0.145), sex (p=0.351) and African American race (p=0.053), donors with the TCF7L2 rs7903146 T allele (TC or TT, 45.5%) were 2.93 times (95% CI 1.02, 8.47) more likely to have a high ICI% than those without it (CC) (p=0.047).

CONCLUSIONS/INTERPRETATION

Overall, these data support the presence of a type 1 diabetes endotype associated with a genetic factor that predisposes to type 2 diabetes, with donors in this category exhibiting less severe beta cell loss. It is possible that in these individuals the disease pathogenesis may include mechanisms associated with type 2 diabetes and thus this may provide an explanation for the poor response to immunotherapies to prevent type 1 diabetes or its progression in a subset of individuals. If so, strategies that target both type 1 diabetes and type 2 diabetes-associated factors when they are present may increase the success of prevention and treatment in these individuals.

Live enteroviruses, but not other viruses, detected in human pancreas at the onset of type 1 diabetes in the DiViD study

AIMS/HYPOTHESIS

Enterovirus (EV) infection of pancreatic islet cells is one possible factor contributing to type 1 diabetes development. We have reported the presence of EV genome by PCR and of EV proteins by immunohistochemistry in pancreatic sections. Here we explore multiple human virus species in the Diabetes Virus Detection (DiViD) study cases using innovative methods, including virus passage in cell cultures.

METHODS

Six recent-onset type 1 diabetes patients (age 24-35) were included in the DiViD study. Minimal pancreatic tail resection was performed under sterile conditions. Eleven live cases (age 43-83) of pancreatic carcinoma without diabetes served as control cases. In the present study, we used EV detection methods that combine virus growth in cell culture, gene amplification and detection of virus-coded proteins by immunofluorescence. Pancreas homogenates in cell culture medium were incubated with EV-susceptible cell lines for 3 days. Two to three blind passages were performed. DNA and RNA were extracted from both pancreas tissue and cell cultures. Real-time PCR was used for detecting 20 different viral agents other than EVs (six herpesviruses, human polyomavirus [BK virus and JC virus], parvovirus B19, hepatitis B virus, hepatitis C virus, hepatitis A virus, mumps, rubella, influenza A/B, parainfluenza 1-4, respiratory syncytial virus, astrovirus, norovirus, rotavirus). EV genomes were detected by endpoint PCR using five primer pairs targeting the partially conserved 5' untranslated region genome region of the A, B, C and D species. Amplicons were sequenced. The expression of EV capsid proteins was evaluated in cultured cells using a panel of EV antibodies.

RESULTS

Samples from six of six individuals with type 1 diabetes (cases) and two of 11 individuals without diabetes (control cases) contained EV genomes (p<0.05). In contrast, genomes of 20 human viruses other than EVs could be detected only once in an individual with diabetes (Epstein-Barr virus) and once in an individual without diabetes (parvovirus B19). EV detection was confirmed by immunofluorescence of cultured cells incubated with pancreatic extracts: viral antigens were expressed in the cytoplasm of approximately 1% of cells. Notably, infection could be transmitted from EV-positive cell cultures to uninfected cell cultures using supernatants filtered through 100 nm membranes, indicating that infectious agents of less than 100 nm were present in pancreases. Due to the slow progression of infection in EV-carrying cell cultures, cytopathic effects were not observed by standard microscopy but were recognised by measuring cell viability. Sequences of 5' untranslated region amplicons were compatible with EVs of the B, A and C species. Compared with control cell cultures exposed to EV-negative pancreatic extracts, EV-carrying cell cultures produced significantly higher levels of IL-6, IL-8 and monocyte chemoattractant protein-1 (MCP1).

CONCLUSIONS/INTERPRETATION

Sensitive assays confirm that the pancreases of all DiViD cases contain EVs but no other viruses. Analogous EV strains have been found in pancreases of two of 11 individuals without diabetes. The detected EV strains can be passaged in series from one cell culture to another in the form of poorly replicating live viruses encoding antigenic proteins recognised by multiple EV-specific antibodies. Thus, the early phase of type 1 diabetes is associated with a low-grade infection by EVs, but not by other viral agents.

Inflammatory Cytokines Rewire the Proinsulin Interaction Network in Human Islets

CONTEXT

Aberrant biosynthesis and secretion of the insulin precursor proinsulin occurs in both type I and type II diabetes. Inflammatory cytokines are implicated in pancreatic islet stress and dysfunction in both forms of diabetes, but the mechanisms remain unclear.

OBJECTIVE

We sought to determine the effect of the diabetes-associated cytokines on proinsulin folding, trafficking, secretion, and β-cell function.

METHODS

Human islets were treated with interleukin-1β and interferon-γ for 48 hours, followed by analysis of interleukin-6, nitrite, proinsulin and insulin release, RNA sequencing, and unbiased profiling of the proinsulin interactome by affinity purification-mass spectrometry.

RESULTS

Cytokine treatment induced secretion of interleukin-6, nitrites, and insulin, as well as aberrant release of proinsulin. RNA sequencing showed that cytokines upregulated genes involved in endoplasmic reticulum stress, and, consistent with this, affinity purification-mass spectrometry revealed cytokine induced proinsulin binding to multiple endoplasmic reticulum chaperones and oxidoreductases. Moreover, increased binding to the chaperone immunoglobulin binding protein was required to maintain proper proinsulin folding in the inflammatory environment. Cytokines also regulated novel interactions between proinsulin and type 1 and type 2 diabetes genome-wide association studies candidate proteins not previously known to interact with proinsulin (eg, Ataxin-2). Finally, cytokines induced proinsulin interactions with a cluster of microtubule motor proteins and chemical destabilization of microtubules with Nocodazole exacerbated cytokine induced proinsulin secretion.

CONCLUSION

Together, the data shed new light on mechanisms by which diabetes-associated cytokines dysregulate β-cell function. For the first time, we show that even short-term exposure to an inflammatory environment reshapes proinsulin interactions with critical chaperones and regulators of the secretory pathway.

Glucose-Dependent Insulin Secretion from β Cell Spheroids Is Enhanced by Embedding into Softer Alginate Hydrogels Functionalised with RGD Peptide

Type 1 diabetes results from the loss of pancreatic β cells, reduced insulin secretion and dysregulated blood glucose levels. Replacement of these lost β cells with stem cell-derived β cells, and protecting these cells within macro-device implants is a promising approach to restore glucose homeostasis. However, to achieve this goal of restoration of glucose balance requires work to optimise β cell function within implants. We know that native β cell function is enhanced by cell-cell and cell-extracellular matrix interactions within the islets of Langerhans. Reproducing these interactions in 2D, such as culture on matrix proteins, does enhance insulin secretion. However, the impact of matrix proteins on the 3D organoids that would be in implants has not been widely studied. Here, we use native β cells that are dispersed from islets and reaggregated into small spheroids. We show these β cell spheroids have enhanced glucose-dependent insulin secretion when embedded into softer alginate hydrogels conjugated with RGD peptide (a common motif in extracellular matrix proteins). Embedding into alginate-RGD causes activation of integrin responses and repositioning of liprin, a protein that controls insulin secretion. We conclude that insulin secretion from β cell spheroids can be enhanced through manipulation of the surrounding environment.

Long-term Outcomes With Islet-Alone and Islet-After-Kidney Transplantation for Type 1 Diabetes in the Clinical Islet Transplantation Consortium: The CIT-08 Study

OBJECTIVE

To determine long-term outcomes for islet-alone and islet-after-kidney transplantation in adults with type 1 diabetes complicated by impaired awareness of hypoglycemia.

RESEARCH DESIGN AND METHODS

This was a prospective interventional and observational cohort study of islet-alone (n = 48) and islet-after-kidney (n = 24) transplant recipients followed for up to 8 years after intraportal infusion of one or more purified human pancreatic islet products under standardized immunosuppression. Outcomes included duration of islet graft survival (stimulated C-peptide ≥0.3 ng/mL), on-target glycemic control (HbA1c <7.0%), freedom from severe hypoglycemia, and insulin independence.

RESULTS

Of the 48 islet-alone and 24 islet-after-kidney transplantation recipients, 26 and 8 completed long-term follow-up with islet graft function, 15 and 7 withdrew from follow-up with islet graft function, and 7 and 9 experienced islet graft failure, respectively. Actuarial islet graft survival at median and final follow-up was 84% and 56% for islet-alone and 69% and 49% for islet-after-kidney (P = 0.007) with 77% and 49% of islet-alone and 57% and 35% of islet-after-kidney transplantation recipients maintaining posttransplant HbA1c <7.0% (P = 0.0017); freedom from severe hypoglycemia was maintained at >90% in both cohorts. Insulin independence was achieved by 74% of islet-alone and islet-after-kidney transplantation recipients, with more than one-half maintaining insulin independence during long-term follow-up. Kidney function remained stable during long-term follow-up in both cohorts, and rates of sensitization against HLA were low. Severe adverse events occurred at 0.31 per patient-year for islet-alone and 0.43 per patient-year for islet-after-kidney transplantation.

CONCLUSIONS

Islet transplantation results in durable islet graft survival permitting achievement of glycemic targets in the absence of severe hypoglycemia for most appropriately indicated recipients having impaired awareness of hypoglycemia, with acceptable safety of added immunosuppression for both islet-alone and islet-after-kidney transplantation.

Hydrolytically Degradable Microgels with Tunable Mechanical Properties Modulate the Host Immune Response

Hydrogel microparticles (microgels) are an attractive approach for therapeutic delivery because of their modularity, injectability, and enhanced integration with the host tissue. Multiple microgel fabrication strategies and chemistries have been implemented, yet manipulation of microgel degradability and its effect on in vivo tissue responses remains underexplored. Here, the authors report a facile method to synthesize microgels crosslinked with ester-containing junctions to afford tunable degradation kinetics. Monodisperse microgels of maleimide-functionalized poly(ethylene-glycol) are generated using droplet microfluidics crosslinked with thiol-terminated, ester-containing molecules. Tunable mechanics are achievable based on the ratio of degradable to nondegradable crosslinkers in the continuous phase. Degradation in an aqueous medium leads to microgel deformation based on swelling and a decrease in elastic modulus. Furthermore, degradation byproducts are cytocompatible and do not cause monocytic cell activation under noninflammatory conditions. These injectable microgels possess time-dependent degradation on the order of weeks in vivo. Lastly, the evaluation of tissue responses in a subcutaneous dorsal pocket shows a dynamic type-1 like immune response to the synthetic microgels, driven by interferon gamma (IFN-γ  ) expression, which can be moderated by tuning the degradation properties. Collectively, this study demonstrates the development of a hydrolytic microgel platform that can be adapted to desired host tissue immune responses.

Engineered immunomodulatory accessory cells improve experimental allogeneic islet transplantation without immunosuppression

Islet transplantation has been established as a viable treatment modality for type 1 diabetes. However, the side effects of the systemic immunosuppression required for patients often outweigh its benefits. Here, we engineer programmed death ligand-1 and cytotoxic T lymphocyte antigen 4 immunoglobulin fusion protein-modified mesenchymal stromal cells (MSCs) as accessory cells for islet cotransplantation. The engineered MSCs (eMSCs) improved the outcome of both syngeneic and allogeneic islet transplantation in diabetic mice and resulted in allograft survival for up to 100 days without any systemic immunosuppression. Immunophenotyping revealed reduced infiltration of CD4+ or CD8+ T effector cells and increased infiltration of T regulatory cells within the allografts cotransplanted with eMSCs compared to controls. The results suggest that the eMSCs can induce local immunomodulation and may be applicable in clinical islet transplantation to reduce or minimize the need of systemic immunosuppression and ameliorate its negative impact.

Performance of islets of Langerhans conformally coated via an emulsion cross-linking method in diabetic rodents and nonhuman primates

Polyethylene glycol (PEG)-based conformal coating (CC) encapsulation of transplanted islets is a promising β cell replacement therapy for the treatment of type 1 diabetes without chronic immunosuppression because it minimizes capsule thickness, graft volume, and insulin secretion delay. However, we show here that our original CC method, the direct method, requiring exposure of islets to low pH levels and inclusion of viscosity enhancers during coating, severely affected the viability, scalability, and biocompatibility of CC islets in nonhuman primate preclinical models of type 1 diabetes. We therefore developed and validated in vitro and in vivo, in several small- and large-animal models of type 1 diabetes, an augmented CC method-emulsion method-that achieves hydrogel CCs around islets at physiological pH for improved cytocompatibility, with PEG hydrogels for increased biocompatibility and with fivefold increase in encapsulation throughput for enhanced scalability.

Expression-based Genome-wide Association Study Links OPN and IL1-RA With Newly Diagnosed Type 1 Diabetes in Children

CONTEXT

Islet autoantibodies (IAbs) are currently the most reliable indicators of islet autoimmunity. However, IAbs do not fully meet the need for the prediction and intervention of type 1 diabetes (T1D). Serological proteins should be great sources for biomarkers.

OBJECTIVE

This work aimed to identify new proteomic biomarkers with the technology of an expression-based genome-wide association study (eGWAS) in children newly diagnosed with T1D.

METHODS

In an attempt to identify additional biomarkers, we performed an eGWAS using microarray data from 169 arrays of the pancreatic islets of T1D rodents (78 T1D cases and 91 controls). We ranked all 16 099 protein-coding genes by the likelihood of differential expression in the pancreatic islets. Our top 20 secreted proteins were screened in 170 children including 100 newly diagnosed T1D, and 50 type 2 diabetes (T2D) and 20 age-matched healthy children. With 6 proteins showing significance, we further conducted a validation study using the second independent set of 400 samples from children including 200 newly diagnosed with T1D, 100 T2D, and 100 age-matched controls.

RESULTS

We identified 2 serum proteins that were significantly changed in T1D vs both control and T2D, and 5 serum proteins were significantly changed both in T1D and T2D vs control. Serum osteopontin (OPN) levels were uniquely higher in T1D (T1D vs controls, P = 1.29E-13 ~ 9.38E-7, T1D vs T2D, P = 2.65E-8 ~ 1.58E-7) with no difference between T2D and healthy control individuals. Serum interleukin 1 receptor antagonist (IL-1RA) levels were lower in T1D compared both with T2D (P = 3.36E-9~0.0236) and healthy participants (P = 1.09E-79 ~ 2.00E-12).

CONCLUSION

Our results suggest that OPN and IL1-RA could be candidates for useful biomarkers for T1D in children.

Cordyceps inhibits ceramide biosynthesis and improves insulin resistance and hepatic steatosis

Ectopic ceramide accumulation in insulin-responsive tissues contributes to the development of obesity and impairs insulin sensitivity. Moreover, pharmacological inhibition of serine palmitoyl transferase (SPT), the first enzyme essential for ceramide biosynthesis using myriocin in rodents reduces body weight and improves insulin sensitivity and associated metabolic indices. Myriocin was originally extracted from fruiting bodies of the fungus Isaria sinclairii and has been found abundant in a number of closely related fungal species such as the Cordyceps. Myriocin is not approved for human use but extracts from Cordyceps are routinely consumed as part of traditional Chinese medication for the treatment of numerous diseases including diabetes. Herein, we screened commercially available extracts of Cordyceps currently being consumed by humans, to identify Cordyceps containing myriocin and test the efficacy of Cordyceps extract containing myriocin in obese mice to improve energy and glucose homeostasis. We demonstrate that commercially available Cordyceps contain variable amounts of myriocin and treatment of mice with a human equivalent dose of Cordyceps extract containing myriocin, reduces ceramide accrual, increases energy expenditure, prevents diet-induced obesity, improves glucose homeostasis and resolves hepatic steatosis. Mechanistically, these beneficial effects were due to increased adipose tissue browning/beiging, improved brown adipose tissue function and hepatic insulin sensitivity as well as alterations in the abundance of gut microbes such as Clostridium and Bilophila. Collectively, our data provide proof-of-principle that myriocin containing Cordyceps extract inhibit ceramide biosynthesis and attenuate metabolic impairments associated with obesity. Moreover, these studies identify commercially available Cordyceps as a readily available supplement to treat obesity and associated metabolic diseases.