Type 1 diabetes (T1D) is a chronic autoimmune disorder characterized by the destruction of insulin-producing beta cells in the pancreas, leading to insulin deficiency and chronic hyperglycemia. The main current therapeutic strategies for clinically overt T1D – primarily exogenous insulin administration combined with blood glucose monitoring – fail to fully mimic physiological insulin regulation, often resulting in suboptimal or insufficient glycemic control. Islet cell transplantation has emerged as a promising avenue for functionally replacing endogenous insulin production and achieving long-term glycemic stability. Here, we provide an overview of current islet replacement strategies, ranging from islet transplantation to stem cell-derived islet cell transplantation, and highlight emerging approaches such as immunoengineering. We examine the advancements in immunosuppressive protocols to enhance graft survival, innovative encapsulation, and immunomodulation techniques to protect transplanted islets, and the ongoing challenges in achieving durable and functional islet integration. Additionally, we discuss the latest clinical outcomes, the potential of gene editing technologies, and the emerging strategies for islet cell regeneration. This review aims to highlight the potential of these approaches to transform the management of T1D and improve the quality of life of individuals affected by this condition.

To test 25-hydroxy vitamin D (25(OH)D) levels among subjects with new-onset type 1 diabetes (T1D) and their association with fasting and stimulated C-peptide at study entry in an open-label randomized trial. We conducted a post hoc secondary analysis of the POSEIDON trial (a Pilot, Safety and Feasibility Trial of High-Dose Omega-3 fatty acids and High-Dose Cholecalciferol Supplementation in Type 1 Diabetes). Eligibility criteria included age 6 to 65 years, T1D of up to 10 years duration, presence of at least 1 islet autoantibody, and stimulated C-peptide ≥0.066 pmol/mL. A total of 18 subjects with new-onset T1D (defined as ≤180 days duration) with paired 25(OH)D levels and a 4-hour mixed meal tolerance test (MMTT) at screening were included. 25(OH)D levels were directly associated with fasting C-peptide (r = 0.589; 95% CI 0.154-0.833; P = .01) but no significant associations were found with MMTT stimulated C-peptide. Ten subjects had 25(OH)D levels <30 ng/mL (56%) and fasting C-peptide was significantly lower compared to those with 25(OH)D levels >30 ng/mL (0.22 ± 0.14 vs 0.41 ± 0.09 pmol/mL; P < .006). 25(OH)D levels were directly associated with fasting C-peptide in youth and adults with newly diagnosed T1D. Low 25(OH)D levels may be associated with more aggressive autoimmunity in patients at risk for T1D potentially leading to a lower beta-cell mass at T1D clinical onset, but larger studies are required to validate these results.

Introduction & Objective: Islet transplantation for T1D is limited by donor availability and need for immunosuppression. Stem cell-derived islets could represent a solution as an unlimited source, but chronic immunosuppression remains a critical barrier. Immunomodulatory SA-FasL engineered microgel (iTOL-100, iTolerance Inc) represents a viable option to eliminate chronic immunosuppression. This study aimed to investigate the effect of human stem cell-derived islets (IsletRx, Kadimastem Ltd) co-transplanted with SA-FasL microgel in streptozotocin-diabetic immunodeficient NSG mice, to assess potential clinical translation. Methods: IsletRx cell clusters were shipped via intercontinental flight. IsletRx was implanted in the epidydimal fat pad at doses from 3 to 9 kIEQ per mouse, alone or with iTOL-100. Over three months of follow-up, animal body weight and glycemia were monitored to assess transplantation effects. Human C-peptide levels were periodically measured and Intraperitoneal Glucose Tolerance Tests (IPGTT) performed. Results: The study demonstrated that IsletRx engrafted, resulting in substantial human C-peptide release and normalization of blood glucose levels. At the highest IsletRx dose (9 kIEQ, approximately 5 million cells), glycemic control improved over 3 months, reaching euglycemia. Importantly, iTOL-100 did not adversely affect stem cell-derived IsletRx function. Histological analyses of the grafts revealed well-preserved stem cell-derived islets. Conclusion: The results indicate the potential of IsletRx as a stem cell-derived islet candidate for the treatment of subjects with T1D. Notably, IsletRx can be shipped intercontinentally, and thus could be delivered worldwide as a functionally competent clinical product. Additionally, our findings indicate that the combination of stem cell-derived IsletRx with the immunomodulatory iTOL-100 microgel does not compromise beta cell function and reversal of diabetes. Disclosure A. Rech Tondin: None. E.S. Yolcu: None. D.M. Hester: None. Y. Gadea: None. G. Vega: None. J. Szust: None. A. revel: None. H. Shirwan: None. A. Garcia: Board Member; iTolerance. Stock/Shareholder; iTolerance, CorAmi. A. Japour: None. M. Revel: Employee; Kadimastem Ltd, Nes Ziona, Israel. C. Ricordi: Advisory Panel; Vertex Pharmaceuticals Incorporated. Consultant; iTolerance, Inc. G. Lanzoni: Stock/Shareholder; Novo Nordisk, Eli Lilly and Company, Pfizer Inc., Medtronic, UnitedHealth Group, Provention Bio, Inc. Funding iTolerance, Inc. (ITOL-SOW-00018263)

This integrative review and perspective article synthesizes current knowledge about the co-morbidity of Type 1 Diabetes (T1D) and sensorineural hearing loss (SNHL), affecting an estimated 9.2 per 1,000 T1D patients annually. Combining data from clinical, preclinical, and mechanistic studies, the article elucidates the complex pathological mechanisms contributing to SNHL in T1D. It is established that T1D accelerates age-related SNHL and brings about detrimental changes in the auditory system, including damage to outer hair cells (OHCs), inner hair cells (IHCs), the stria vascularis (SV), and the spiral ligament (SL). Furthermore, T1D-associated peripheral neuropathy, microvascular damage, and chronic inflammation in the inner ear contribute to auditory deficits. Although some consistency exists between animal models and human conditions, notable discrepancies warrant the refinement of preclinical models to more accurately mirror human clinical scenarios. This perspective article highlights the need for targeted research to bridge existing knowledge gaps and accelerate the development of early-stage interventions for SNHL in T1D patients. Advancements in this field hold the promise of enhancing clinical prognosis and improving the quality of life of individuals having T1D.

A network of co-hepato/pancreatic stem/progenitors exists in pigs and humans in Brunner’s Glands in the submucosa of the duodenum, in peribiliary glands (PBGs) of intrahepatic and extrahepatic biliary trees, and in pancreatic duct glands (PDGs) of intrapancreatic biliary trees, collectively supporting hepatic and pancreatic regeneration postnatally. The network is found in humans postnatally throughout life and, so far, has been demonstrated in pigs postnatally at least through to young adulthood. These stem/progenitors in vivo in pigs are in highest numbers in Brunner’s Glands and in PDGs nearest the duodenum, and in humans are in Brunner’s Glands and in PBGs in the hepato/pancreatic common duct, a duct missing postnatally in pigs. Elsewhere in PDGs in pigs and in all PDGs in humans are only committed unipotent or bipotent progenitors. Stem/progenitors have genetic signatures in liver/pancreas-related RNA-seq data based on correlation, hierarchical clustering, differential gene expression and principal component analyses (PCA). Gene expression includes representative traits of pluripotency genes (SOX2, OCT4), endodermal transcription factors (e.g. SOX9, SOX17, PDX1), other stem cell traits (e.g. NCAM, CD44, sodium iodide symporter or NIS), and proliferation biomarkers (Ki67). Hepato/pancreatic multipotentiality was demonstrated by the stem/progenitors’ responses under distinct ex vivo conditions or in vivo when patch grafted as organoids onto the liver versus the pancreas. Therefore, pigs are logical hosts for translational/preclinical studies for cell therapies with these stem/progenitors for hepatic and pancreatic dysfunctions.

Abstract A network of co-hepato/pancreatic stem/progenitors exists postnatally in the intrahepatic, extrahepatic and intrapancreatic biliary trees of pigs and humans and found to support hepatic and pancreatic regeneration throughout life. The stem/progenitors have genetic signatures in liver/pancreas-related RNA-seq data based on Correlation, hierarchical clustering, KEGG and Short Time-series Expression Miner (STEM) analyses. Representative phenotypic traits are expression of pluripotency genes (SOX2, OCT4, KLF4), endodermal transcription factors (SOX9, SOX17, PDX1, NGN3), other stem cell traits (NCAM, EpCAM, BMI-1, CD44), and proliferation biomarkers (Ki67). Stem/progenitor niches in vivo are in peribiliary glands (PBGs) throughout the intrahepatic and extrahepatic biliary tree, in duodenal submucosal glands (Brunner’s Glands), and in pancreatic duct glands (PDGs). The highest numbers of niches in humans are in PBGs in the hepato/pancreatic common duct, a duct missing in pigs; by contrast, the highest numbers in pigs are in Brunner’s Glands and in a subset of PDGS, those nearest to the duodenum. Elsewhere in PDGs in the porcine pancreas, and in all PDGs in the human pancreas, are found only committed unipotent and bipotent progenitors. Multipotentiality of the stem/progenitors was indicated by their ability to yield hepatic versus pancreatic fates under distinct ex vivo conditions or in vivo when organoids of them were transplanted onto liver versus pancreas using patch grafting strategies. The findings establish pigs as logical hosts for translational/preclinical studies assessing grafts of organoids of the biliary tree’s co-hepato/pancreatic stem cells as cell therapies for diseases and dysfunctions in liver and pancreas both for humans and for veterinary animals.

Pancreatic islet cells, and in particular insulin-producing beta cells, are centrally involved in the pathogenesis of diabetes mellitus. These cells are of paramount importance for the endocrine control of glycemia and glucose metabolism. In Type 1 Diabetes, islet beta cells are lost due to an autoimmune attack. In Type 2 Diabetes, beta cells become dysfunctional and insufficient to counterbalance insulin resistance in peripheral tissues. Therapeutic agents have been developed to support the function of islet cells, as well as to inhibit deleterious immune responses and inflammation. Most of these agents have undesired effects due to systemic administration and off-target effects. Typically, only a small fraction of therapeutic agent reaches the desired niche in the pancreas. Because islets and their beta cells are scattered throughout the pancreas, access to the niche is limited. Targeted delivery to pancreatic islets could dramatically improve the therapeutic effect, lower the dose requirements, and lower the side effects of agents administered systemically. Targeted delivery is especially relevant for those therapeutics for which the manufacturing is difficult and costly, such as cells, exosomes, and microvesicles. Along with therapeutic agents, imaging reagents intended to quantify the beta cell mass could benefit from targeted delivery. Several methods have been developed to improve the delivery of agents to pancreatic islets. Intra-arterial administration in the pancreatic artery is a promising surgical approach, but it has inherent risks. Targeted delivery strategies have been developed based on ligands for cell surface molecules specific to islet cells or inflamed vascular endothelial cells. Delivery methods range from nanocarriers and vectors to deliver pharmacological agents to viral and non-viral vectors for the delivery of genetic constructs. Several strategies demonstrated enhanced therapeutic effects in diabetes with lower amounts of therapeutic agents and lower off-target side effects. Microvesicles, exosomes, polymer-based vectors, and nanocarriers are gaining popularity for targeted delivery. Notably, liposomes, lipid-assisted nanocarriers, and cationic polymers can be bioengineered to be immune-evasive, and their advantages to transport cargos into target cells make them appealing for pancreatic islet-targeted delivery. Viral vectors have become prominent tools for targeted gene delivery. In this review, we discuss the latest strategies for targeted delivery of therapeutic agents and imaging reagents to pancreatic islet cells.

Patch grafting, a novel strategy for transplantation of stem/progenitor organoids into porcine livers, has been found successful also for organoid transplantation into other normal or diseased solid organs in pigs and mice. Each organoid contained similar to 100 cells comprised of biliary tree stem cells (BTSCs), co-hepato/pancreatic stem/ progenitors, and partnered with early lineage stage mesenchymal cells (ELSMCs), angioblasts and precursors to endothelia and stellate cells. Patch grafting enabled transplantation into livers or pancreases of >= 10(8th) (pigs) or 10(6th-7th) (mice) organoids/patch. Graft conditions fostered expression of multiple matrix-metalloproteinases (MMPs), especially secretory isoforms, resulting in transient loss of the organ's matrix-dictated histological features, including organ capsules, and correlated with rapid integration within a week of organoids throughout the organs and without emboli or ectopic cell distribution. Secondarily, within another week, there was clearance of graft biomaterials, followed by muted expression of MMPs, restoration of matrix-dictated histology, and maturation of donor cells to functional adult fates. The ability of patch grafts of organoids to rescue hosts from genetic-based disease states was demonstrated with grafts of BTSC/ELSMC organoids on livers, able to rescue NRG/FAH-KO mice from type I tyrosinemia, a disease caused by absence of fumaryl acetoacetate hydrolase. With the same grafts, if on pancreas, they were able to rescue NRG/Akita mice from type I diabetes, caused by a mutation in the insulin 2 gene. The potential of patch grafting for cell therapies for solid organs now requires translational studies to enable its adaptation and uses for clinical programs.

COVID-19 is without any doubt the worst pandemic we have faced since the H1N1 virus outbreak. Even if vaccination against SARS-CoV-2 infection is becoming increasingly available, a more feasible approach for COVID-19 prevention and therapy is still needed. Evidence of a pathological link between metabolic diseases and severe forms of COVID-19 has stimulated critical reflection and new considerations. In particular, an abnormal immune response observed in certain patients with SARS-CoV-2 infection suggested possible common predisposing risk factors with autoimmune diseases such as Type 1 Diabetes (T1D). Correct supplementation with dietary factors may be key to preventing and counteracting both the underlying metabolic impairment and the complications of COVID-19. A set of agents may inhibit the cytokine storm and hypercoagulability that characterize severe COVID-19 infection: vitamin D3, omega-3 polyunsaturated fatty acids, polyphenols like pterostilbene, polydatin and honokiol, which can activate anti-inflammatory and antioxidant sirtuins pathways, quercetin, vitamin C, zinc, melatonin, lactoferrin and glutathione. These agents could be highly beneficial for subjects who have altered immune responses. In this review, we discuss the antiviral and metabolic effects of these dietary factors and propose their combination for potential applications in the prevention and treatment of COVID-19. Rigorous studies will be fundamental for validating preventive and therapeutic protocols that could be of assistance to mitigate disease progression following SARS-CoV-2 infection.

Epithelial cell therapies have been at an impasse because of inefficient methods of transplantation to solid organs. Patch grafting strategies were established enabling transplantation of >= 107th organoids/patch of porcine GFP+ biliary tree stem/progenitors into livers of wild type hosts. Grafts consisted of organoids embedded in soft (similar to 100 Pa) hyaluronan hydrogels, both prepared in serum-free Kubota's Medium; placed against target sites; covered with a silk backing impregnated with more rigid hyaluronan hydrogels (similar to 700 Pa); and use of the backing to tether grafts with sutures or glue to target sites. Hyaluronan coatings (similar to 200-300 Pa) onto the serosal surface of the graft served to minimize adhesions with neighboring organs. The organ's clearance of hyaluronans enabled restoration of tissue-specific paracrine and systemic signaling, resulting in return of normal hepatic histology, with donor parenchymal cells uniformly integrated amidst host cells and that had differentiated to mature hepatocytes and cholangiocytes. Grafts containing donor mature hepatocytes, partnered with endothelia, and in the same graft biomaterials as for stem/progenitor organoids, did not engraft. Engraftment occurred if porcine liver-derived mesenchymal stem cells (MSCs) were co-transplanted with donor mature cells. RNA-seq analyses revealed that engraftment correlated with expression of matrix-metalloproteinases (MMPs), especially secreted isoforms that were found expressed strongly by organoids, less so by MSCs, and minimally, if at all, by adult cells. Engraftment with patch grafting strategies occurred without evidence of emboli or ectopic cell distribution. It was successful with stem/progenitor organoids or with cells with a source(s) of secreted MMP isoforms and offers significant potential for enabling cell therapies for solid organs.

Patch grafting, a novel strategy for transplantation of stem/progenitor organoids into porcine livers, has been found successful also for organoid transplantation into other normal or diseased solid organs in pigs and mice. Each organoid contained ~ 100 cells comprised of biliary tree stem cells (BTSCs), co-hepato/pancreatic stem/progenitors, and partnered with early lineage stage mesenchymal cells (ELSMCs), angioblasts and precursors to endothelia and to stellate cells. Patch grafting enabled transplantation into livers or pancreases of ≥ 107th (pigs) or ≥ 106th (mice) organoids/patch. Graft conditions fostered expression by organoids of multiple matrix-metalloproteinases (MMPs), especially secretory isoforms, resulting in transient loss of the organ’s matrix-dictated histological features, including organ capsules, and correlated with rapid integration within a week of organoids throughout the organs and without emboli or ectopic cell distribution. Secondarily, within another week, there was clearance of graft biomaterials, followed by muted expression of MMPs, restoration of matrix-dictated histology, and maturation of donor cells to functional adult fates. The ability of patch grafts of organoids to rescue hosts from genetic-based disease states was demonstrated with grafts of BTSC/ELSMC organoids on livers, able to rescue NRG/FAH-KO mice from type I tyrosinemia, a disease caused by absence of fumaryl acetoacetate hydrolase. With the same grafts, if on pancreas, they were able to rescue NRG/Akita mice from type I diabetes, caused by a mutation in the insulin 2 gene. The potential of patch grafting for cell therapies for solid organs now requires translational studies to enable its adaptation and uses for clinical programs.

OBJECTIVE: We aimed at explaining the mechanism of therapeutic effect of Umbilical Cord Mesenchymal Stem Cells (UC-MSC) in subjects with COVID-19 Acute Respiratory Distress Syndrome (ARDS). Patients with COVID-19 ARDS present with a hyperinflammatory response characterized by high levels of circulating pro-inflammatory mediators, including tumor necrosis factor α and β (TNFα and TNFβ). Inflammatory functions of these TNFs can be inhibited by soluble TNF Receptor 2 (sTNFR2). In patients with COVID-19 ARDS, UC-MSC appear to impart a robust anti-inflammatory effect, and treatment is associated with remarkable clinical improvements. We investigated the levels of TNFα, TNFβ and sTNFR2 in blood plasma samples collected from subjects with COVID-19 ARDS enrolled in our trial of UC-MSC treatment. PATIENTS AND METHODS: We analyzed plasma samples from subjects with COVID-19 ARDS (n=24) enrolled in a Phase 1/2a randomized controlled trial of UC-MSC treatment. Plasma samples were obtained at Day 0 (baseline, before UC-MSC or control infusion), and Day 6 post infusion. Plasma concentrations of sTNFR2, TNFα, and TNFβ were evaluated using a quantitative multiplex protein array. RESULTS: Our data indicate that at Day 6 after infusion, UC-MSC recipients develop significantly increased levels of plasma sTNFR2 and significantly decreased levels of TNFα and TNFβ, compared to controls. CONCLUSIONS: These observations suggest that sTNFR2 plays a mechanistic role in mediating UC-MSC effect on TNFα and TNFβ plasma levels, determining a decrease in inflammation in COVID-19 ARDS.

Background & Aim: Mesenchymal stem cells (MSCs) have been shown to modulate hyperinflammation, promote tissue repair and secrete antimicrobial factors. MSCs have been studied in clinical trials of autoimmune diseases, inflammatory disorders, refractory GvHD and acute respiratory distress syndrome (ARDS). MSCs can be isolated and expanded from multiple tissues, including umbilical cord (UC). A number of clinical studies demonstrated safety and feasibility of UCMSCs therapy for the treatment of COVID-19 ARDS. UC-derived MSCs are easily available and can be quickly expanded to relevant numbers. UC-MSCs have an extended population doubling capacity and express low levels of class I and class II leukocyte antigen, which may reduce alloreactivity. To meet clinical manufacture demands, UC-MSC production requires an innovative, scaled-up manufacturing platform. We describe the manufacturing strategy developed in support of a double-blind, randomized, controlled UC- MSC clinical trial in subjects with COVID-19 ARDS. Methods, Results & Conclusion: UC-MSC Final Product was manufactured from the master cell bank (MCB) derived from subepithelial lining of a UC from a healthy term delivery, in cGMP conditions. Utilizing a 2D culture xenogeneic protein-free process, UC-MSC MCB was culture-expanded during 3 expansion cycles, in tissue culture treated vessels with increased surface area for each expansion, in commercially available tissue culture media supplemented with platelet lysate. Cells were harvested during log phase, at 75-80% confluence. The manufacturing process yielded ~ 300x increase in total viable cells at the end of the last expansion cycle. The Final Product was cryopreserved using a controlled rate freezer. Each subject in the treatment group received two doses of 100×106 UC-MSCs. A single UC-MSC Final Product batch was sufficient to treat all subjects randomized to the treatment group and complete the trial. The final product was tested for identity (label verification), effectiveness by viable cell dose and cell viability (>80%), safety by assessment of endotoxin ( 90%, CD34/CD45 <10%). UC-MSC cell doses prepared for infusion produced similar results to UC-MSC Final Product when tested to confirm product identity, effectiveness, safety and purity. The developed 2D culture and expansion process can be successfully scaled up without compromising integrity of the final UC-MSC product.