bluuebunny/crossref_metadata_2025_split huggingface dataset:
112-OR: Adoptive Transfer of CD4+ T Cells with Reduced iPLA2b Expression Mitigates T1D Development
Authors: WHITE TAYLEUR , RAMANADHAM SASANKA , CHALFANT CHARLES , DILORENZO TERESA 
Published: June 2021

Type 1 diabetes (T1D) is a T-cell mediated autoimmune disease characterized by the destruction of insulin-producing pancreatic islet β-cells. An understudied area is the role lipid signaling plays in this process. We find that the Ca2+-independent phospholipase A2β (iPLA2β) is induced under a diabetic milieu and mitigation of iPLA2β activity attenuates β-cell death. iPLA2β, a member of the PLA2 family, hydrolyzes the sn-2 substituent from glycerophospholipid substrates to yield a free fatty acid. When the fatty acid is arachidonic acid, it can be metabolized to eicosanoids, many of which are pro-inflammatory. To address our overarching hypothesis that iPLA2β-derived lipids (iDLs) contribute to T1D development, we investigated the role of immune cell-iDLs by utilizing a splenocyte adoptive transfer protocol. Our findings suggested that reduced iPLA2β expression in splenocytes: (1) delayed T1D incidence, (2) improved glucose homeostasis and (3) reduced the production of iDLs. To further elucidate the link between iPLA2 expression and T lymphocytes in T1D progression, we investigated the role of T-cell derived iDLs by utilizing combinations of T-cell transfers. We isolated CD4+/8+ T-cells from splenocytes prepared from 6-week-old donor NOD and NOD iPLA2β+/- (NOD.HET). These were transferred to 4-week-old immunodeficient NOD.scid recipient mice. We find that: (1) WT4/8 recipient mice develop T1D between 14-16 weeks of age. In contrast, T1D onset in HET4/8 recipient mice is delayed by 16 weeks, (2) temporal IPGTTs reveal that recipient mice of HET4/8 T-cells were more glucose tolerant, compared to recipients of the WT4/8 T-cells, (3) reduced iPLA2β expression in CD4 T cells proved to be effective in delaying T1D progression, and (4) HET donor T-cell production of select pro-inflammatory iDLs is decreased. These findings suggest that iPLA2β in CD4 T-cells is a critical contributor to the production of pro-inflammatory iDLs and could be a potential target in reducing T1D development.

Disclosure
T. White: None. S. Ramanadham: None. C. Chalfant: None. T. Dilorenzo: None.

Funding
National Institute of Diabetes and Digestive and Kidney Diseases (R01DK110292); National Institute of Allergy and Infectious Diseases (R21AI146743)
1126-P: Activating SKAP2 Mutation Linked to Diabetes with Multiple Autoimmune and Inflammatory Conditions
Authors: CHAMBERLAIN CHESTER , RUTSCH NIKLAS , DIXON WESLEY , LETOURNEAU-FREIBERG LISA R. , PHILIPSON LOUIS H. , GERMAN MICHAEL , ANDERSON MARK S. , LOWELL CLIFFORD A. 
Published: June 2021

Recent insights into human autoimmunity and immune tolerance have come from studies of rare monogenic disorders. For example, type 1 diabetes (T1D) and thyroid autoimmunity are frequent features in patients with mutations in AIRE and FOXP3. Dissecting the consequences of these mutations has improved our understanding of the role of central T cell tolerance and T regulatory cells in controlling these organ-specific autoimmune diseases. Over the last decade, rapid advances in genetic sequencing have now allowed for a deeper exploration and discovery of rare variants that are linked to disease with techniques like whole exome sequencing. Using this approach in both kindreds and outlier patients with de novo germline mutations, there has been expanding discovery of mutations in other pathways with a link to organ-specific autoimmunity that include STAT3, STAT1, CTLA4, and LRBA. Here, we utilized a similar approach on a single patient with T1D and other autoimmune and inflammatory conditions. We identified a de novo heterozygous c.457G&gt;A/p.Gly153Arg mutation in the SKAP2 gene. SKAP2 encodes a critical mediator of integrin signaling pathways that regulate myeloid immune cell function. Monocyte-derived macrophages from the individual displayed enhanced activity of integrin pathways and a migratory phenotype in the absence of chemokine stimulation, consistent with SKAP2 p.Gly153Arg being constitutively active. The p.Gly153Arg variant, located in the well-conserved lipid-binding loop, induced similar phenotypes when expressed in a human macrophage cell line. We propose that SKAP2 p.Gly153Arg is a gain-of-function, pathogenic mutation that disrupts myeloid immune cell function, resulting in a break in immune tolerance and T1D. This particular mutation in a patient with T1D and multiple autoimmunity implicates a role for activating SKAP2 variants in autoimmune T1D.

Disclosure
C. Chamberlain: None. N. Rutsch: None. W. Dixon: None. L. R. Letourneau-freiberg: None. L. H. Philipson: Advisory Panel; Self; Nevro Corp., Research Support; Self; Provention Bio, Inc. M. German: Stock/Shareholder; Self; Viacyte, Inc. M. S. Anderson: Consultant; Self; Provention Bio, Inc., VielaBio, Stock/Shareholder; Self; Medtronic, Merck & Co., Inc. C. A. Lowell: None.

Funding
The Leona M. and Harry B. Helmsley Charitable Trust (G-2018PG-T1D018); Larry L. Hillblom Foundation (2014-D-004-NET); University of California San Francisco Parnassus Flow Core (RRID:SCR_018206); National Institutes of Health (P30 DK063720, S101S10OD021822-01); German Research Foundation (ZA428/11-1, ZA428/18-1, INST211/604-1)
113-OR: Identification of Sorafenib for the Treatment of Type 1 Diabetes
Authors: ZENG QIN , SONG JIANFENG , SUN XIAOXIAO , WANG DANDAN , XIAO YANG , ZHOU ZHIGUANG , DENG TUO 
Published: June 2021

Type 1 diabetes (T1D) is an immune-mediated disease characterized by impairment of pancreatic beta cells. To date, a comprehensive cure is not available. Th1 cell activation is considered a key mediator of the pathogenesis of T1D. IL-12-induced STAT4 activation is a paramount signaling pathway to instigate Th1 cell differentiation. Targeting IL-12-induced Th1 cell differentiation seems to be an effective way to block the development of T1D. However, given the critical function of Th1 in the immune system, the potential side effects hinder the application of anti-Th1 therapy in the treatment of T1D. To identify safe anti-Th1 treatment(s), we screened the FDA-approved tyrosine kinase inhibitor (TKI) drug library using an IL-12-induced Th1 differentiation cell model. We found that sorafenib, an oral anti-cancer drug, is a top contender for inhibition of Th1 differentiation relative to induced toxicity. Sorafenib inhibited IL-12-induced Th1 cell differentiation in a dose-dependent manner without any change of CD4+ T-cell viability. Treatment of NOD mice with sorafenib significantly impeded the development of T1D and ameliorated insulitis, which coincided with a specifically decreased aggregate of Th1 cell population in pancreas but not in peripheral immune organs. Inflammatory cytokines and Th1 signature transcription factor Tbet mRNA expression in pancreas were decreased in sorafenib-treated NOD mice compared to vehicle-treated NOD mice. Mechanistically, sorafenib directly inhibited JAK2 activity and blocked IL-12-induced phosphorylations of JAK2 and STAT4.
In conclusion, sorafenib administration inhibits the development of T1D by suppressing IL-12b/JAK2/STAT4 signaling-mediated Th1 cell differentiation specifically in pancreas in NOD mice. Since sorafenib is classified as an FDA-approved drug, it serves as a preliminary lead point for additional experimentation and may be a promising therapeutic for T1D in humans.

Disclosure
Q. Zeng: None. J. Song: None. X. Sun: None. D. Wang: None. Y. Xiao: None. Z. Zhou: None. T. Deng: None.
1130-P: A GWAS of Gene by Smoking Interaction on Type 2 Diabetes
Authors: FERDOS SEPIDEH N. , SALEM RANY 
Published: June 2021

Genome wide association studies (GWAS) of type 2 diabetes (T2D) have identified hundreds of genetic variants. However, the majority of these studies fail to consider the multifactorial nature and the interplay of genetic and environmental factors on disease risk, e.g., gene x environment interaction analyses. The role of smoking as a modulator in the association between genetic variants and T2D is of particular importance, since it is a modifiable risk factor for T2D. We performed a large-scale gene x smoking analysis on 345,955 individuals from 14 studies retrieved from dbGaP and UK Biobank. Phenotypic data was reviewed and harmonized prior to performing a gene by smoking GWAS for each study. A joint (main and interaction effect) framework was performed for each study. Individual study GWAS statistics were combined through meta-analysis, stratified by racial/ethnic group. The study sample includes 40,994 diabetics and 34,764 current smokers, and 324,834 of European-, 9,040 of African-, 6,125 of Hispanic-, and 5,956 of Asian-ancestry subjects. Results from the meta-analysis in the European ancestry group revealed a genome wide significant signal (p&lt;5x10-8) in the TCF7L2 gene (main effect, p-value 9.59x10-33) and several genome-suggestive (p&lt;1x10-5) loci. We are currently expanding the analyses to include data from a total of 20 studies and 700,000 subjects. Gene by smoking interaction analysis on T2D underscores the importance of both genetic and environmental risk factors and has the potential to unveil novel variants, genes, and biological pathways that influence disease vulnerability typically missed by traditional analytic approaches.

Disclosure
S. N. Ferdos: None. R. Salem: None.

Funding
Tobacco Related Disease Research Program (T29IR0770)
1135-P: Type 2 Diabetes Modulates DNA Methylation in Human Sperm
Authors: SU LEI , WOLFS DANIELLE , HIVERT MARIE-FRANCE , PATEL JAY , RICHARDSON LAUREN , CHARMANT CHARNICE O. , ISGANAITIS ELVIRA M. , PATTI MARY-ELIZABETH 
Published: June 2021

Paternal obesity and diabetes are associated with cardiometabolic risk in offspring. To test the hypothesis that paternal metabolism could exert these effects via modulation of the sperm epigenome, we collected motile sperm at two study visits 3 months apart in men with and without T2D (NCT03860558). Sperm DNA methylation was quantified in 32 samples using the Infinium MethylationEPIC array. HbA1c was higher in men with T2D vs. controls (7.6±1.1% vs. 5.2±0.2%, n=9 vs. 7, p&lt;0.0001). Age (49.6±7.5 vs. 40.9±12.3 years, p=0.1), BMI (34.4±6.7 vs. 30.3±4.0 kg/m2, p=0.17), waist circumference and fat % were similar. There were no differences in sperm concentration or motility, testosterone, LH, estradiol, or prolactin levels. Methylation data were pre-processed using Partek Genomics Suite 7.19. After filtering cross-reactive probes and probes overlapping with SNP, 790508 probes were analyzed. Two-way ANOVA (disease group/time as factors) revealed 7 CpG sites differentially methylated between control and T2D (FDR q&lt;0.05, differences in beta&gt;0.2), including sites annotated to SLFN5, MMAA, and LOC101927829. All 7 sites were hypermethylated in T2D, with mean difference in beta of 26.4%. Paired analysis between study visits for individual participants revealed no significant CpG, indicating stability of sperm methylation over time. Genes annotated to differentially methylated CpG at both study visits (n=89, nominal p&lt;0.01) were enriched for genes involved in morphogenesis and neuron development; the majority of these CpG also had higher methylation in T2D. In a linear regression model, 10 CpG sites showed positive and 2 sites showed negative association with HbA1c (FDR q&lt;0.05).
In summary, DNA methylation is altered in motile sperm from men with T2D, with hypermethylation at significant CpG sites. These alterations may reflect differential transcriptional regulation at developmentally important loci, and should be investigated as potential contributors to the impact of paternal metabolism on offspring.

Disclosure
L. Su: None. D. Wolfs: None. M. Hivert: None. J. Patel: None. L. Richardson: None. C. O. Charmant: None. E. M. Isganaitis: None. M. Patti: Consultant; Self; Cello Health, Fractyl Laboratories, Inc., MBX, Poxel SA, WGBH, Other Relationship; Self; Xeris Pharmaceuticals, Inc., Research Support; Self; Dexcom, Inc.

Funding
National Institutes of Health (R21HD091974)
1137-P: Liver Regulatory Variants and Genes at Metabolic Trait Loci
Authors: PANDEY GAUTAM , CURRIN KEVIN , VADLAMUDI SWAROOPARANI , BROADAWAY K. ALAINE , MOHLKE KAREN L. 
Published: June 2021

Genome-wide association studies (GWAS) have identified many loci that affect liver- and lipid-related metabolic traits, but the causal variants, target genes and mechanisms for most loci have not been characterized. GWAS loci are often enriched in tissue-specific transcriptional regulatory elements that drive physiological changes, and loci can be annotated with colocalized molecular quantitative traits for gene expression (eQTL) and accessible chromatin (caQTL) to identify candidate variants and genes. We previously profiled chromatin accessibility in 20 human liver samples, identified caQTL variants that colocalized with GWAS loci for metabolic traits, and predicted target genes based on promoter proximity, Hi-C chromatin contact with a promoter, and co-localization with liver eQTL. Here, we examined selected GWAS loci and tested variants for effects on gene regulation. We prioritized loci based on trait, gene function, and QTL characteristics and selected four variant-gene pairs to study. To evaluate effects of specific variants on gene expression, we performed transcriptional reporter assays in HepG2 cells. Three caQTL variants exhibited significant (P&lt;0.05) allelic differences in transcriptional activity. rs13395911, near EFHD1 and associated with liver enzyme gamma glutamyl transferase, showed allelic differences in enhancer activity (P=0.008). In addition, rs9556404, near GPR180 and associated with triglycerides, and rs34003091, near ZNF329 and associated with LDL-cholesterol, also showed significant allelic effects on transcriptional activity (P&lt;0.05). To study EFHD1 function in liver metabolism, we used gene-specific shRNA constructs in HepG2 cells and observed up to 90% reduction of EFHD1 mRNA expression compared to scramble shRNA. Subsequent metabolic assays will test role of EFHD1 on hepatic lipid and glucose metabolism. These data identified candidate regulatory variants that may be responsible for nearby GWAS loci and suggest genes as therapeutic targets for fatty liver disease.

Disclosure
G. Pandey: None. K. Currin: None. S. Vadlamudi: None. K. Broadaway: None. K. L. Mohlke: None.
1142-P: Update on BCG Clinical Trial Programs in Patients with Advanced Type 1 Diabetes
Authors: KUHTREIBER WILLEM , TAKAHASHI HIROYUKI , KEEFE RYAN , NELSON KACIE , NG NATHAN , BRALEY JOAN , ZHENG HUI , FAUSTMAN DENISE L. 
Published: June 2021

The bacillus Calmette-Guerin (BCG) vaccine was first introduced a century ago for tuberculosis prevention and is today being tested in clinical trials for treatment of diverse forms of autoimmunity, including type 1 diabetes (T1D). Long-term follow up of a Phase I study of the BCG vaccine in longstanding T1D revealed potential disease-modulating effects after repeated BCG vaccination, including long-term reductions of HbA1c, death of autoreactive cells, modest restoration of insulin secretion and induction of beneficial regulatory T cells (Tregs). Here we provide an update on the BCG clinical trial program current underway at Massachusetts General Hospital (MGH): enrollment numbers, study timelines and interim outcomes for key T1D biomarkers. To date, 236 patients have been enrolled in the randomized and open-label MGH trials and 143 patients have received at least two doses of BCG, 34 of whom are being followed in open-label, unblinded trials. Enrollment of 150 participants in a pediatric study is planned for 2021. Data from ongoing analysis of the open-label BCG trials shows lowered insulin needs and decreases in HbA1c as compared to reference populations. Patients are also being monitored by RNAseq, epigenetics, Treg cell numbers and Treg signature gene expression to better define the mechanism of beneficial effects. We show a gradual and stable 3-year time course of demethylation of signature Treg genes known to be associated with Treg potency, including Foxp3, which was observed to be over-methylated at baseline in T1D and, over 3 years after BCG vaccination, demethylated to a level close to controls without T1D. The clinical time course of BCG-related improvements (i.e., improvement in HbA1C) appears to correlate with the time course of Treg induction through epigenetic modifications.

Disclosure
W. Kuhtreiber: None. H. Takahashi: None. R. Keefe: None. K. Nelson: None. N. Ng: None. J. Braley: None. H. Zheng: None. D. L. Faustman: None.
1146-P: Persistent Graft Function after Islet Allotransplantation Into Prevascularized Sernova Cell Pouch Device: Preliminary Results from the University of Chicago
Authors: BACHUL PIOTR J. , GENERETTE GABRIELA S. , PYDA JORDAN S. , BOREK PETER , PEREZ-GUTIERREZ ANGELICA , GOLAB KAROLINA , BASTO LINDSAY , PEREA LAURENCIA , TIBUDAN MARTIN , JUENGEL BRADEN , KUMAR JAYANT , THOMAS CELESTE C. , PHILIPSON LOUIS H. , FUNG JOHN , WITKOWSKI PIOTR 
Published: June 2021

Introduction: Pre-vascularized Sernova Cell Pouch (SCP) device was developed to provide an optimal environment for cell/islet engraftment in the extravascular space. A first-in-human pilot study showed SCP safety/islet vascularization; however, conditions did not allow detectable islet function. We present preliminary results of phase I/II study testing safety and efficacy of modified SCPs in islet allotransplantation (ITx).
Material and Methods: 6 patients with longstanding T1DM and multiple severe hypoglycemic events (SHEs) were enrolled. Immunosuppression (Thymoglobulin, Tacrolimus, and Mycophenolate) was initiated 3 weeks after abdominal wall SCP surgical implantation. ITx occurred at 3 weeks and 6 months after implantation. Sentinel SCPs were explanted for histopathological evaluation 3 months after transplant. Islet graft function was assessed based on continuous glucose monitoring (CGM), c-peptide, and insulin requirement.
Results: First patient presented with persistent stimulated serum c-peptide at 6 months after 1st and 2nd ITx into SCP. After 2nd ITx, glucose control improved substantially reaching optimal target values for CGM with only 5% of Time Below Range (TBR). Second patient at 3 months after 2nd ITx had positive stimulated serum c-peptide (0.48 ng/mL) with reduction of HbA1c from 10.6% to 7.6%, decreased insulin requirement from 49 to 28 u/day, improved CGM with TBR &lt;4%, and reduction in Time Above Range (from 75% to 48%). Two patients await ITx and evaluation.
Conclusion: Persistent islet graft function with sustained blood levels of c-peptide, reduction of HbA1c, improved CGM parameters, reduction of SHEs, and decreased total daily insulin requirement was achieved in first 2 patients after ITx into abdominal wall SCPs. Modified approaches, including suspending islets in serum, optimizing islets/dose, and smaller pellet volumes, will likely improve engraftment and outcomes.

Disclosure
P. J. Bachul: None. B. Juengel: None. J. Kumar: None. C. C. Thomas: None. L. H. Philipson: Advisory Panel; Self; Nevro Corp., Research Support; Self; Provention Bio, Inc. J. Fung: None. P. Witkowski: None. G. S. Generette: None. J. S. Pyda: None. P. Borek: None. A. Perez-gutierrez: None. K. Golab: None. L. Basto: None. L. Perea: None. M. Tibudan: None.

Funding
JDRF; Sernova, Corp.
115-LB: Liver-Derived FGF21 Mediates the Promoting Effect of Glucagon Receptor Antagonism on Beta-Cell Regeneration in Type 2 Diabetic Mice
Authors: CUI XIAONA , WEI TIANJIAO , FENG JIN , YANG JIN , YAN HAI , WEI RUI , HONG TIANPEI 
Published: June 2021

Objective: Based on the clear role for glucagon in the pathogenesis of diabetes, glucagon-blocking therapies have been pursued as a therapeutic strategy for this disease. Here, we used REMD 2.59, a human antagonistic glucagon receptor (GCGR) monoclonal antibody (mAb), to clarify the effects of GCGR mAb in promoting pancreatic β cell regeneration in type 2 diabetes (T2D), and its potential mechanism.
Methods: GCGR mAb was administrated weekly for 4 weeks in db/db mice and HFD/STZ-induced T2D mice, including different lineage-tracing mice. The plasma insulin and glucagon were determined by using ELISA. The evaluation of islet morphology was performed with immunofluorescent analysis. GCGR mAb was also treated in the systemic Fgf21 gene knockout (Fgf21-/-) and hepatocyte-specific Fgf21 gene knockout (Fgf21Hep-/-) T2D mice.
Results: Treatment with GCGR mAb lowered blood glucose, improved glucose tolerance, and elevated plasma glucagon and insulin levels in both db/db mice and HFD/STZ-induced T2D mice. The β cell dedifferentiation as indicated by β cell lineage-tracing was blocked by GCGR mAb. The β cell proliferation as indicated by insulin+ and BrdU+ cells was boosted by GCGR mAb. The α-to-β cell conversion, as evaluated by glucagon+ insulin+ cells and confirmed by α cell lineage-tracing, was facilitated by GCGR mAb. After GCGR mAb treatment, some insulin+ cells were located in the duct region or even colocalized with duct cell markers, suggestive of duct-derived β cell neogenesis that was also verified by Ngn3+ cell lineage-tracing. Notably, GCGR mAb could still improve glucose tolerance and increase β cell mass, but these effects were attenuated in Fgf21-/- and Fgf21Hep-/- T2D mice compared with WT T2D mice.
Conclusions: GCGR mAb promotes β cell regeneration via inhibiting β cell dedifferentiation and promoting β cell self-replication, α-to-β cell conversion and duct-derived β cell neogenesis in T2D mice, which is partly mediated by liver-derived FGF21.

Disclosure
X. Cui: None. T. Wei: None. J. Feng: None. J. Yang: None. H. Yan: Board Member; Self; REMD Biotherapeutics, Other Relationship; Spouse/Partner; REMD Biotherapeutics. R. Wei: None. T. Hong: Speaker’s Bureau; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Merck Sharp & Dohme Corp., Novo Nordisk, Sanofi.

Funding
National Natural Science Foundation of China (81830022)