Introduction and Objective: The hallmark of T1D is the destruction of pancreatic insulin producing β-cells by autoreactive T cells. The quest for new antigen-specific autoreactive cells as well as for strategies that may target them are highly required to provide a more successful therapeutic option for T1D. Starting from many evidence suggesting a potential role of glial glutamate transporter 1 (GLT-1) in autoimmunity, this study aims to identify and mechanistically characterize GLT-1 autoreactive T cells in vitro and in vivo. Methods: In vitro: GLT-1-derived peptides immunogenicity was tested by ELISPOT and proliferation assay, while GLT-1 autoreactive T cells were characterized by scRNA-seq and subsequently isolated with newly designed dextramers. In vivo: GLT-1-derived peptides ability to modify T1D onset was tested in NOD mice and NOD SCID animals, a more stringent model of disease. Autoimmune response was evaluated as well as insulitis score. Results: GLT-1-derived peptides were able to significantly increase the number of CD4+ IFN-g producing T cells, stimulate proliferation and expression of key genes involved in T cell activation/cytotoxicity (GZMA, CXCR6, CCL5, GZMK, KLRG1, KLRB1, PRF1) in a subpopulation of CD4+ T cells in T1D patients. Moreover, we were able to identify of GLT-1 autoreactive T cells with our newly designed dextramers. In vivo, GLT-1-derived peptides treatment significantly increased the autoimmune response in splenocytes from GLT-1-treated NOD animals compared to untreated mice. Finally, in the more stringent model, splenocytes obtained from normoglycemic GLT-1-treated NOD mice injected in NOD SCID animals induce a more severe diabetes compared to NOD SCID receiving splenocytes from normoglycemic NOD mice. Conclusion: Our findings indicate the existence of the new population of GLT-1 autoreactive T cells both in human and mice establishing a future blueprint for a novel therapy for T1D aimed at targeting these cells, thus preventing islet destruction. Disclosure E. Assi: None. F. D'Addio: Other - Founder and consultant; Ended; Enthera srl. V. Usuelli: None. C. Loretelli: None. M. Ben Nasr: None. M. Zocchi: None. A. Petrazzuolo: None. A. Maestroni: None. G. Rossi: None. I. Pastore: Advisory Panel; Ended; Sanofi. Board Member; Ended; Novo Nordisk. A. Rossi: Consultant; Ended; Roche Diabetes Care, Abbott Diabetes. L. Montefusco: None. G. Zuccotti: None. P. Fiorina: Board Member; Ended; Novo Nordisk, Lilly, AstraZeneca, Boehringer Ingelheim International GmbH.

Lymphocytes B cells (B cells) play a determinant role in the pathogenesis of type 1 diabetes (T1D); indeed, B cells antigen-presentation capabilities are largely described as a main contributing pathogenic factor. Recent evidences highlighted the role of islet antigen-reactive B cells as a perpetuated contributor to autoantibodies seroconversion and the progression to the late stages of the disease. A loss of B cells anergy towards islet-specific antigens, can be recognized in T1D. Aside from their well characterized role during the pathogenesis and early onset of T1D, a fundamental regulatory role of a subset of B cells, namely regulatory B cells, has proven its relevance in the time course of the disease. Since targeting B cells showed little or no additional benefits; instead, harnessing strategies to expand B regulatory cells could represent an attractive therapeutic path to tackle inflammation and curb diabetes.

Introduction and Objective: Despite being a major contributor to reduced life expectancy in type 1 diabetes (T1D), cardiovascular disease (CVD) and T1D-associated cardiomyopathy remain poorly understood. Insulin-like growth factor binding protein-7 (IGFBP7), a member of the IGFBPs, was found elevated in serum of patients with heart failure and kidney disease. Clinical studies in patients with diabetes showed that a change in serum IGFBP7 > 50% individually mediated 22% of cardiac outcomes, pointing at a residual cardiovascular risk linked to IGFBP7-mediated injury and at IGFBP7 as a new druggable target. The aim of our study was to test if IGFBP7 blockade protects from CVD and diabetic cardiomyopathy in vitro and in vivo. Methods: A human IGFBP7 inhibitor was generated by phage display and tested in vitro in human cardiomyocytes. In vivo efficacy was evaluated in a murine model of ischemic heart disease (C57BL6/J mice) and in streptozotocin (STZ)-induced diabetic mice. Treatment effects were assessed by analyzing infarct size, cardiac dysfunction and fibrosis. IGFBP7 level was also measured in patients with T1D and CVD (n=30 vs. non-diabetic controls) and in treated/untreated mice. Results: Serum IGFBP7 was 2-fold higher in patients with T1D and CVD (p<0.001 vs. controls) and in diabetic mice with ischemic CVD. In vitro, inhibition of IGFBP7 protected cardiomyocytes from diabetes- and pressure overload-induced damage. In vivo, IGFBP7 blockade preserved cardiac function, reduced cardiac fibrosis and promoted tissue remodeling. This protective effect was associated with up to a 40% decrease in serum IGFBP7 level. Conclusion: IGFBP7 is actively involved in the onset/progression of CVD in T1D and contributes to T1D-cardiomyopathy. IGFBP7 blockade prevents cardiac dysfunction and promotes cardiac remodeling in vitro and in vivo. As treatments for CVD are lacking in T1D, IGFBP7 inhibition may represent a new approach to target the IGFBP7-mediated residual cardiovascular risk and improve cardiac outcomes in this patients’ population. Disclosure F. D'Addio: Other - Founder and consultant; Ended; Enthera srl. A. Petrazzuolo: None. E. Assi: None. A. Maestroni: None. V. Usuelli: None. M. Zocchi: None. G. Rossi: None. R. Fiorina: None. A. Gandolfi: None. V. Cimino: None. L. Bucciarelli: None. L. Montefusco: None. C. Loretelli: None. M. Ben Nasr: None. P. Fiorina: Board Member; Ended; Novo Nordisk, Amgen Inc., Bristol-Myers Squibb Company.

Mechanisms by which mucosal regeneration is abrogated in inflammatory bowel disease (IBD) are still under investigation, and a role for an intestinal stem cell (ISC) defect is now emerging. Herein, we report an abnormal ISC death that occurs in Crohn's disease, which exacerbates colitis, limits ISC-dependent mucosal repair, and is controlled through the death factor Transmembrane protein 219 (TMEM219). Large alterations in TMEM219 expression were observed in patients with Crohn's disease, particularly in those with active disease and/or those who were nonresponders to conventional therapy, confirming that TMEM219 signaling is abnormally activated and leads to failure of the mucosal regenerative response. Mechanistic studies revealed a proapoptotic TMEM219-mediated molecular signature in Crohn's disease, which associates with Caspase-8 activation and ISC death. Pharmacological blockade of the IGFBP3/TMEM219 binding/signal with the recombinant protein ecto-TMEM219 restored the self-renewal abilities of miniguts generated from patients with Crohn's disease in vitro and ameliorated DSS-induced and T cell-mediated colitis in vivo, ultimately leading to mucosal healing. Genetic tissue-specific deletion of TMEM219 in ISCs in newly generated TMEM219fl/flLGR5cre mice revived their mucosal regenerative abilities both in vitro and in vivo. Our findings demonstrate that a TMEM219-dependent ISC death exacerbates colitis and that TMEM219 blockade reestablishes intestinal self-renewal properties in IBD.

Introduction and Objective: Serum levels of neuroblastoma suppressor of tumorigenicity 1 (NBL1) positively correlate with the 10-years risk of developing end stage kidney disease (ESKD) in patients with either type 1 or type 2 diabetes. Moreover, NBL1 causes podocyte death, in vitro. The aim of our study was to test whether NBL1 blocking agents could prevent podocyte death, in vitro, and delay diabetic kidney disease (DKD) onset, in vivo. Methods: We screened a library of NBL1 inhibitors through phage display by using an in vitro cell death assay, which measured NBL1-induced apoptosis of human immortalized podocytes. Stem cell-derived human kidney organoids were used as translational model. NBL1 inhibitors were tested, in vivo, in streptozotocin (STZ)-induced DKD and in Db/Db mice. Efficacy of NBL1 blocking agents was evaluated by quantifying mesangial expansion, pro-fibrotic response, expression of podocyte-specific markers and by measuring urinary creatinine and albumin. Results: Our study demonstrated that NBL1 inhibition markedly reduced NBL1-induced podocyte death, in vitro, and rescued the expression of podocyte markers in human kidney organoids. More importantly, when administered in vivo, NBL1 inhibitors reduced urinary albumin and creatinine, mesangial expansion, and renal fibrosis, thus preventing the development of DKD. Conclusion: Novel therapies aimed at blocking/delaying DKD onset and/or progression to ESKD in patients with diabetes are still needed. Our findings demonstrate that NBL1 inhibition protects diabetic mice from renal damage by preventing podocyte death, thereby confirming NBL1 as novel therapeutic target for DKD. A. Petrazzuolo: None. E. Assi: None. A. Maestroni: None. V. Usuelli: None. M. Zocchi: None. G. Rossi: None. I. Pastore: Advisory Panel; Sanofi. Board Member; Novo Nordisk. A. Monestiroli: Consultant; Nephris, Alia Therapeutics. M. Ben Nasr: None. F. D'Addio: Advisory Panel; Sanofi. A. Krolewski: None. P. Fiorina: Consultant; Novo Nordisk, AstraZeneca. Board Member; Boehringer-Ingelheim.

Introduction and Objective: The Transmembrane Protein 219 (TMEM219) signaling is a novel death receptor on β-cells that is activated in Type 1 Diabetes (T1D). Therefore, TMEM219 targeting may serve as a therapeutic option in diabetes to prevent β-cell loss. This study aimed to evaluate the ability of the anti-TMEM219 monoclonal human IgG4 antibody (mAb) Ebrasodebart to block the TMEM219 signaling in vitro and in vivo in preventing T1D onset in the non-obese diabetic (NOD). Methods: In vitro: Apoptosis of the human β cell were evaluated after culture with/without recombinant human IGFBP3 or pooled T1D serum and with/without Ebrasodebart. In vivo: Ebrasodebart ability to prevent T1D onset was tested in NOD mice and NOD SCID animals, a more stringent model of disease. Immunophenotype and autoimmune response were evaluated as well as insulitis score. Results: In vitro: Ebrasodebart treatment significantly reduced apoptosis in human β cells and in pancreatic islets in the presence of IGFBP3 or of pooled T1D serum. In vivo: Ebrasodebart treatment resulted in significant prevention of diabetes onset in 10 weeks old NOD mice with 90% of animals free from diabetes at 24 weeks of age as compared to untreated controls. While no change was evident in the immunophenotype at flow cytometry, the autoimmune response analyzed ex vivo by rechallenging splenocytes with the CD4 and CD8 restricted islet peptides was significantly reduced. Moreover, the insulitis score was also normalized in treated animals as compared to untreated controls. Finally, in a more stringent model, 75% of NOD SCID mice injected with splenocytes obtained from normoglycemic Ebrasodebart-treated NOD mice did not develop diabetes while NOD SCID animals receiving splenocytes from hyperglycemic NOD mice progressed to overt hyperglycemia. Conclusion: Our findings indicate that direct inhibition of TMEM219 signaling, which is dysregulated in T1D, preserved the beta cell mass and may thus represent a novel therapeutic opportunity for patients with T1D. E. Assi: None. A. Petrazzuolo: None. M. Nardini: None. V. Marin: None. M. Zangarini: None. S. Porzio: Employee; Enthera srl. S. Lodovichi: None. G. Amabile: None. A. Maestroni: None. V. Usuelli: None. C. Loretelli: None. M. Ben Nasr: None. M. Zocchi: None. I. Pastore: Advisory Panel; Sanofi. Board Member; Novo Nordisk. G. Rossi: None. F. D'Addio: Advisory Panel; Sanofi. L.M. Olson: Stock/Shareholder; AbbVie Inc. Board Member; Lassen Therapeutics. Stock/Shareholder; Lassen Therapeutics. Employee; Enthera Pharmaceuticals. Stock/Shareholder; Enthera Pharmaceuticals, Dianthus. P. Fiorina: Consultant; Novo Nordisk, AstraZeneca. Board Member; Boehringer-Ingelheim.

Introduction and Objective: Fibrosis can be commonly found in patients with advanced type 1 or type 2 diabetes and diabetic complications. Hyperglycemia, lipotoxic injury and insulin resistance can trigger secretion of extracellular matrix (ECM) and promote epithelial-to-mesenchymal transition (EMT) in several organs. IGFBP5 is upregulated in fibrotic diseases and has been found to be associated with diabetic kidney disease progression. The mechanism and the receptor mediating IGFBP5’s actions are unknown. Here we aimed at studying the pro-fibrotic role of IGFBP5 in promoting EMT and ECM deposition. Methods: A549 cell line, primary epithelial cells, primary fibroblasts and 3D cultures were used as in vitro and ex vivo models. The expression/secretion of fibronectin and collagen were assessed by qRT-PCR, western blot and ELISA and used as markers of fibrosis. Results: We demonstrated that IGFBP5 was expressed in fibroblasts and highly released by epithelial cells and that the fibrotic factor TGF-β1 promoted IGFBP5 expression in both cell types. We showed that IGFBP5 enhanced the TGF-β1-dependent EMT in terms of fibronectin and collagen expression and deposition in epithelial cells. On the contrary, IGFBP5 silencing/blockade reverted the TGF-β1 fibrogenic response. Importantly, we identified CD248 as a potential membrane receptor of IGFBP5 mediating its profibrotic activity. CD248 was upregulated by TGF-β1 in epithelial cells, suggesting an enhanced activity of the IGFBP5/CD248 axis in the fibrotic response. The blockade of CD248 reverted the ex vivo IGFBP5-dependent EMT and ECM deposition. Conclusion: Our data characterize for the first time the IGFBP5/CD248 axis and its role in promoting EMT in epithelial cells and fibrosis, elucidating a new signaling axis that can be targeted as a novel therapeutic strategy to treat fibrosis in diabetic complications. M. Zocchi: None. C. Loretelli: None. M. Nardini: None. E. Assi: None. S. Lodovichi: None. A. Petrazzuolo: None. A. Maestroni: None. V. Usuelli: None. M. Ben Nasr: None. V. Marin: None. M. Zangarini: None. S. Porzio: Employee; Enthera srl. F. D'Addio: Advisory Panel; Sanofi. G. Amabile: None. L.M. Olson: Stock/Shareholder; AbbVie Inc. Board Member; Lassen Therapeutics. Stock/Shareholder; Lassen Therapeutics. Employee; Enthera Pharmaceuticals. Stock/Shareholder; Enthera Pharmaceuticals, Dianthus. P. Fiorina: Consultant; Novo Nordisk, AstraZeneca. Board Member; Boehringer-Ingelheim.

Introduction and Objective: The IL-8/CXCR1-CXCR2 axis has been demonstrated to be impaired in T1D, thus we hypothesize that targeting IL-8/CXCR1-CXCR2 axis may contribute to the expansion and differentiation of regulatory B cells. Methods: We profiled by FACS analysis murine and human Bregs (CD19+IL-10+ cells) isolated from patients with T1D as compared to healthy controls (HC) for IL-8/CXCR1-CXCR2 expression under resting/stimulating conditions. We tested the effect of murine Bregs expanded by LPS/rIL-2 in the presence of different titrations of Reparixin (1nM, 10nM and 50nM) in a co-culture assay with anti-CD3/anti-CD28 stimulated T cells or with diabetogenic T-cells (BDC2.5 stimulated CD4+ T cells), during a proliferation assay. Results: Our data showed that IL-8 and CXCR2 were found significantly higher on Bregs and also on non-Bregs (CD19+IL-10- cells) in patients with T1D as compared to HC (p<0.05). While under stimulating conditions (anti-CD40L/LPS), CXCR1 and CXCR2 were found significantly higher on Bregs from patients with T1D as compared to HC (p<0.05). The murine data in NOD on Bregs generated under stimulating conditions (LPS/IL-2) revealed an upregulation of CXCL1 and CXCR1 during the time course of T1D as NOD hyperglycemic showed the highest expression while those naturally protected from T1D showed the lowest expression (p<0.05). We next studied the effect of targeting IL-8/CXCR1-CXCR2 during murine Breg generation. A significant suppression of CD4+/CD8+ T cell effector proliferation in all conditions where Bregs were added as compared to T cells alone (p<0.001). Particularly, a reduced T-cell response toward islet autoantigens with Bregs expanded in the presence of Reparixin 10nM showed the most potent effect as compared to untreated (p<0.001). Lastly, we confirmed the immunoregulatory capacities of Bregs generated using Reparixin through an inhibition of IFN-γ production by diabetogenic T-cells (p<0.05). Conclusion: Altogether, targeting IL-8/CXCR1-CXCR2 axis may help to establish a novel tailored Breg-based immunotherapy in T1D. S. Khalefa: None. M. Ben Nasr: None. V. Usuelli: None. P. Yerra: None. E. Assi: None. A. Petrazzuolo: None. M. Zocchi: None. F. D'Addio: Advisory Panel; Sanofi. C. Loretelli: None. I. Pastore: Advisory Panel; Sanofi. Board Member; Novo Nordisk. L. Montefusco: None. A. Rossi: Consultant; Roche Diabetes Care, Ascensia Diabetes Care, Ypsomed AG. M. Lunati: None. G. Zuccotti: None. M. Allegretti: Employee; Dompé. P. Fiorina: Consultant; Novo Nordisk, AstraZeneca. Board Member; Boehringer-Ingelheim. The study is part of the activities planned in the co? financed project "Ladari.un as new Juvenile Diabetes Inhibitory Agent (LJDIA)" presented by Dompe under the Call "Fondo crescita sostenibile - Proposal n. 1410 bando MISE DM 02/08/2019 and consecutive DD 02/10/2019" ("MISE Grant").

Insulin-like growth factor binding protein 3 (IGFBP3) signals through the death receptor TMEM219 to modulate survival of target cells; inhibition of this signaling has been associated with a rescue of intestinal stem cell death. Here we report the screening, generation, and characterization of fully human IgG monoclonal antibodies (mAbs) through phage display or by hybridoma technology, that block IGFBP3 or TMEM219. Both anti-IGFBP3 and anti-TMEM219 mAbs showed high affinity binding with the target antigens and potent effects in protecting self-renewal ability of intestinal stem cells in in vitro relevant assays. Among all the mAbs tested, anti-TMEM219 mAbs generated by phage display, particularly Ent001, showed the highest score in displacing the IGFBP3/TMEM219 binding and in rescuing intestinal stem cells (ISC) markers expression and function in IGFBP3-cultured human mini-guts obtained from healthy donors. In human in vitro proof-of-concept studies, in which we generated mini-guts from patients with immune-mediated intestinal disease such as Crohn's disease, Ent001 successfully restored mini-guts growth and ISC markers' expression, while expression of the proapoptotic IGFBP3-related factor Caspase 8 was downregulated. In vivo, in models of DSS-induced chronic colitis and in inflammatory-mediated carcinogenesis, Ent001 significantly improved disease activity index and histological score, restored mucosal morphology and abrogated the development of carcinomas, leading to mucosal healing. In summary, Ent001 represents a novel IGFBP3/TMEM219 inhibitor to be further tested and developed in clinical studies as a novel therapeutic in immune-mediated and inflammatory intestinal diseases.

Pancreatic beta cells replenishment is considered the next therapeutic option for type 1 diabetes; while stimulating endogenous beta cells proliferation is the “holy grail” for those patients with exhausted beta cell mass. Here we are demonstrating that the pro-apoptotic receptor TMEM219 is expressed in fetal pancreas, in beta cell precursors and in in vitro embryonic-derived endocrine progenitors. TMEM219 signaling negatively regulates beta cells at early stages and induces Caspase 8-mediated cell death. Pharmacological blockade of TMEM219 further rescued beta cell precursor and proliferation markers, and decreased cell death, both in islets and in in vitro-derived endocrine progenitors, allowing for beta cell preservation. While addressing the upstream controlling TMEM219 expression, we determined the TMEM219 miRNet; indeed, one of those miRNAs, miR-129-2, is highly expressed in human islets, particularly in patients at risk or with established type 1 diabetes. miR-129-2 mimic downregulated TMEM219 expression in islets, in in vitro embryonic-derived endocrine progenitors and in highly proliferating insulinoma-derived cells. Moreover, miR-129-2 inhibitor induced a TMEM219 overexpression in insulinoma-derived cells, which restored cell proliferation and functional markers, thus acting as endogenous regulator of TMEM219 expression. The TMEM219 upstream regulator miR129-2 controls the fate of beta cell precursors and may unleash their regenerative potentials to replenish beta cells in type 1 diabetes.

Abstract Background Intestinal mucosa regeneration is disrupted in inflammatory bowel disease as Chron’s disease, but whether this relies on a defect in intestinal stem cells remains to be established. Methods Transcriptome and receptome profile in Crohn’s disease bioptic samples demonstrated a defect in intestinal stem cells (ISCs). The TMEM219 knockout mouse, in which TMEM219 expression is abrogated on ISCs was tested in dextran sulfate sodium (DSS) acute colitis model. DSS-induced chronic colitis was also used to confirm in vivo relevance for TMEM219 blockade in mucosal recovery. Results An increased intestinal stem cells death and dysfunction in colonic samples obtained from patients with Crohn’s disease was observed, which is controlled through the death factor TMEM219. Based on a receptome analysis, we documented large alterations in the expression of the death receptor TMEM219 in patients with Crohn’s disease, particularly in those with refractory disease and/or non responders to conventional therapy, which were paralleled by altered peripheral levels of the TMEM219 ligand, insulin-like growth factor binding protein 3 (IGFBP3). Pharmacological blockade of the IGFBP3/TMEM219 axis restored the self-renewal abilities of mini-guts generated from patients with Crohn’s disease in vitro, ameliorated DSS-induced colitis in vivo and favored mucosal healing. Genetic deletion of TMEM219 in intestinal stem cells in newly generated TMEM219flflLGR5cre mice restored mucosal regenerative abilities both in vitro and in vivo. Conclusion Our findings demonstrate that genetic and pharmacological TMEM219 blockade re-establishes intestinal self-renewal properties and offers a therapeutic opportunity for mucosal healing in inflammatory bowel disease.

Introduction & Objective: Approximately 50% of patients with new-onset Type 1 Diabetes (T1D) experience a temporary recovery in pancreatic β-cell function, termed the "honeymoon" (HM) phase, lasting approximately 7-9 months on average, and only rarely extending to years. This phase provides a crucial window for interventions to preserve insulin secretion, yet the factors contributing to its occurrence remain unclear. This study presents the first comprehensive multi-omic profiling of children with new-onset T1D in an extended honeymoon phase (ExMoon), revealing potential molecular targets for preserving β-cell mass and function. Methods: Patients in ExMoon were defined by insulin dose-adjusted HbA1c (IDAA1c) below 9 and C peptide >300 pmol/l, sustained for at least 9 months. We conducted analyses of PBMC immunophenotype, immunoreactivity to islet antigens, serum secretomics, proteomics/metabolomics/lipidomics, and PBMC transcriptomics using flow cytometry, ELISpot, immunomagnetic separation, mass spectrometry, and RNA sequencing, respectively. Profiles of ExMoon patients were compared to age- and gender-matched patients with T1D not in the HM phase (n=10 per group), with 10 matched nondiabetic patients included as additional controls. Results: Differential serum levels of immune factors (IP-10, IL-2, FGF2), proteins (TGM2, SIR4), metabolites (kynurenine), and lipids (myristic acid and monoarachidonic acid triglyceride 18:0_38:6) were observed in ExMoon compared to the T1D group. PBMCs obtained from patients of the two groups exhibited distinct expression patterns of ERAP2, TSKS mRNAs, and of miR-339-3p, miR-8087-3p miRNAs. No differences were found in the proportion of immune cell subpopulations and islet autoreactivity between the ExMoon and T1D patient cohorts. Conclusion: Our unbiased multiomic approach identified several immune and non-immune factors as potential molecular candidates for targeted therapies aimed at preserving β-cell mass and function. Disclosure C. Loretelli: None. A. Gouda Abdelrahman Abdelsalam: None. M. Ben Nasr: Research Support; Altheia Sciences. V. Usuelli: None. E. Assi: None. M. Zocchi: None. A. Petrazzuolo: None. A. Petitti: None. G. Cannalire: None. F. D'Addio: None. C. Mameli: None. P. Fiorina: None. Funding Fondazione "Romeo ed Enrica Invernizzi"

Glucagon-like peptide-1 receptor (GLP-1R) is a key regulator of glucose metabolism known to be expressed by pancreatic β cells. We herein investigated the role of GLP-1R on T lymphocytes during immune response. Our data showed that a subset of T lymphocytes expresses GLP-1R, which is upregulated during alloimmune response, similarly to PD-1. When mice received islet or cardiac allotransplantation, an expansion of GLP-1Rpos T cells occurred in the spleen and was found to infiltrate the graft. Additional single-cell RNA sequencing (scRNA-seq) analysis conducted on GLP-1Rpos and GLP-1Rneg CD3+ T cells unveiled the existence of molecular and functional dissimilarities between both subpopulations, as the GLP-1Rpos are mainly composed of exhausted CD8 T cells. GLP-1R acts as a T cell-negative costimulatory molecule, and GLP-1R signaling prolongs allograft survival, mitigates alloimmune response, and reduces T lymphocyte graft infiltration. Notably, GLP-1R antagonism triggered anti-tumor immunity when tested in a preclinical mouse model of colorectal cancer.

Purpose of review: The purine nucleotide adenosine triphosphate (ATP) is released into extracellular spaces as extracellular ATP (eATP) as a consequence of cell injury or death and activates the purinergic receptors. Once released, eATP may facilitate T-lymphocyte activation and differentiation. The purpose of this review is to elucidate the role of ATP-mediated signaling in the immunological events related to type 1 diabetes (T1D). Recent findings: T lymphocytes mediate immune response during the onset of T1D and promote pancreatic islet or whole pancreas rejection in transplantation. Recent data suggest a potential role for eATP in early steps of T1D onset and of allograft rejection. In different preclinical experimental models and clinical trials, several drugs targeting purinergic signaling have been employed to abrogate lymphocyte activation and differentiation, thus representing an achievable treatment to prevent/revert T1D or to induce long-term islet allograft function. Summary: In preclinical and clinical settings, eATP-signaling inhibition induces immune tolerance in autoim-mune disease and in allotransplantation. In this view, the purinergic system may represent a novel therapeutic target for auto-and allo-immunity.

AIMS:The use of advanced hybrid closed loop systems is spreading due to the beneficial effects on glycometabolic control obtained in patients with type 1 diabetes. However, hypoglycemic episodes can be sometimes a matter of concern. We aim to compare the hypoglycemic risk of an advanced hybrid closed loop system and a predictive low glucose suspend sensor augmented pump. METHODS:In this retrospective three months observational study, we included 30 patients using Medtronic Minimed™ 780G advanced hybrid closed loop system and 30 patients using a Medtronic Minimed™ predictive low glucose suspend sensor augmented pump. RESULTS:The advanced hybrid closed loop system reduced the time spent above 180 mg/dL threshold and increased the time in range as compared to the predictive low glucose suspend. No severe hypoglycemia occurred in both groups and no differences were observed in the percentage of time spent below 70 mg/dl and 54 mg/dl glucose threshold. Nevertheless, more hypoglycemic episodes were recorded during daytime, but not in nighttime, with the use of the advanced hybrid closed loop system. CONCLUSIONS:Our results confirmed the general improvement of glycemic outcomes obtained with the advanced hybrid closed loop system; however more hypoglycemic episodes during daytime were evident.