Comparison of Omentum and Subcutis as Implant Sites for Device-Encapsulated Human iPSC-Derived Pancreatic Endoderm in Nude Rats.

Subcutaneous implants of device-encapsulated stem cell-derived pancreatic endoderm (PE) can establish a functional beta cell mass (FBM) with metabolic control in immune-compromised mice. In a study with human-induced pluripotent stem cell-PE, this outcome was favored by a preformed pouch which allowed lesion-free insertion of devices in a pre-vascularized site. This was not reproduced in nude rats, known to exhibit a higher innate reactivity than mice and therefore relevant as preclinical model: a dense fibrotic capsule formed around subcutis (SC) implants with virtually no FBM formation.

Function and composition of pancreatic islet cell implants in omentum of type 1 diabetes patients.

Intraportal (IP) islet cell transplants can restore metabolic control in type 1 diabetes patients, but limitations raise the need for establishing a functional beta cell mass (FBM) in a confined extrahepatic site. This study reports on function and composition of omental (OM) implants after placement of islet cell grafts with similar beta cell mass as in our IP-protocol (2-5.10 beta cells/kg body weight) on a scaffold.

The MicroRNA Landscape of Acute Beta Cell Destruction in Type 1 Diabetic Recipients of Intraportal Islet Grafts.

Ongoing beta cell death in type 1 diabetes (T1D) can be detected using biomarkers selectively discharged by dying beta cells into plasma. microRNA-375 (miR-375) ranks among the top biomarkers based on studies in animal models and human islet transplantation. Our objective was to identify additional microRNAs that are co-released with miR-375 proportionate to the amount of beta cell destruction.

Insulitis in the pancreas of non-diabetic organ donors under age 25 years with multiple circulating autoantibodies against islet cell antigens.

Autoantibodies against islet cell antigens are routinely used to identify subjects at increased risk of symptomatic type 1 diabetes, but their relation to the intra-islet pathogenetic process that leads to positivity for these markers is poorly understood. We screened 556 non-diabetic organ donors (3 months to 24 years) for five different autoantibodies and found positivity in 27 subjects, 25 single- and two double autoantibody-positive donors. Histopathological screening of pancreatic tissue samples showed lesion characteristic for recent-onset type 1 diabetes in the two organ donors with a high-risk profile, due to their positivity for multiple autoantibodies and HLA-inferred risk.

Formation of amyloid in encapsulated human pancreatic and human stem cell-generated beta cell implants.

Detection of amyloid in intraportal islet implants of type 1 diabetes patients has been proposed as cause in their functional decline. The present study uses cultured adult human islets devoid of amyloid to examine conditions of its formation. After intraportal injection in patients, amyloid deposits <15 µm diameter were identified in 5%-12% of beta cell containing aggregates, 3-76 months posttransplant.

Insulitis and lymphoid structures in the islets of Langerhans of a 66-year-old patient with long-standing type 1 diabetes.

Insulitis is a characteristic inflammatory lesion consisting of immune cell infiltrates around and within the pancreatic islets of patients with recent-onset type 1 diabetes (T1D). The infiltration is typically mild, both in terms of the number of infiltrating cells and the number of islets affected. Here, we present an unusual histopathological case study of a 66-year-old female patient with long-standing T1D, insulitis, and islet-associated lymphoid tissue.

Retraction Note: Transient cytokine treatment induces acinar cell reprogramming and regenerates functional beta cell mass in diabetic mice.

This article has been retracted; see accompanying Retraction Note, which can be accessed via a link at the top of the paper.

Evidence of Tissue Repair in Human Donor Pancreas After Prolonged Duration of Stay in Intensive Care.

M2 macrophages play an important role in tissue repair and regeneration. They have also been found to modulate β-cell replication in mouse models of pancreatic injury and disease. We previously reported that β-cell replication is strongly increased in a subgroup of human organ donors characterized by prolonged duration of stay in an intensive care unit (ICU) and increased number of leukocytes in the pancreatic tissue.

Stromal-targeting radioimmunotherapy mitigates the progression of therapy-resistant tumors.

Radioimmunotherapy (RIT) aims to deliver a high radiation dose to cancer cells, while minimizing the exposure of normal cells. Typically, monoclonal antibodies are used to target the radionuclides to cancer cell surface antigens. However, antibodies face limitations due to their poor tumor penetration and suboptimal pharmacokinetics, while the expression of their target on the cancer cell surface may be gradually lost.

Cell Mass Increase Associated with Formation of Glucose-Controlling β-Cell Mass in Device-Encapsulated Implants of hiPS-Derived Pancreatic Endoderm.

Device-encapsulated human stem cell-derived pancreatic endoderm (PE) can generate functional β-cell implants in the subcutis of mice, which has led to the start of clinical studies in type 1 diabetes. Assessment of the formed functional β-cell mass (FBM) and its correlation with in vivo metabolic markers can guide clinical translation. We recently reported ex vivo characteristics of device-encapsulated human embryonic stem cell-derived (hES)-PE implants in mice that had established a metabolically adequate FBM during 50-week follow-up.

Glucocorticoids and checkpoint tyrosine kinase inhibitors stimulate rat pancreatic beta cell proliferation differentially.

Cell therapy for diabetes could benefit from the identification of small-molecule compounds that increase the number of functional pancreatic beta cells. Using a newly developed screening assay, we previously identified glucocorticoids as potent stimulators of human and rat beta cell proliferation. We now compare the stimulatory action of these steroid hormones to a selection of checkpoint tyrosine kinase inhibitors that were also found to activate the cell cycle-in beta cells and analyzed their respective effects on DNA-synthesis, beta cell numbers and expression of cell cycle regulators.

Increase Functional β-Cell Mass in Subcutaneous Alginate Capsules With Porcine Prenatal Islet Cells but Loss With Human Adult Islet Cells.

Alginate (Alg)-encapsulated porcine islet cell grafts are developed to overcome limitations of human islet transplantation. They can generate functional implants in animals when prepared from fetal, perinatal, and adult pancreases. Implants have not yet been examined for efficacy to establish sustained, metabolically adequate functional β-cell mass (FBM) in comparison with human islet cells.

Combined Analysis of GAD65, miR-375, and Unmethylated Insulin DNA Following Islet Transplantation in Patients With T1D.

Aim: Several biomarkers have been proposed to detect pancreatic β cell destruction in vivo but so far have not been compared for sensitivity and significance.

Methods: We used islet transplantation as a model to compare plasma concentrations of miR-375, 65-kDa subunit of glutamate decarboxylase (GAD65), and unmethylated insulin DNA, measured at subpicomolar sensitivity, and study their discharge kinetics, power for outcome prediction, and detection of graft loss during follow-up.

Results: At 60 minutes after transplantation, GAD65 and miR-375 consistently showed near-equimolar and correlated increases proportional to the number of implanted β cells.

An analytical comparison of three immunoassay platforms for subpicomolar detection of protein biomarker GAD65.

A disproportional increase of circulating GAD65 within hours from an intraportal islet allotransplantation has been validated as biomarker of beta cell loss and poor functional outcome. More sensitive assays are, however, needed to allow detection of episodes of subtle beta cell loss during late-stage graft rejection or in the peri-onset period of type 1 diabetes. We applied the same sandwich monoclonal antibody couple reactive towards the C- and N-terminus of GAD65 on three advanced immunoassay platforms-the Cytometric Bead Array (CBA, Becton, Dickinson and Company), ElectroChemiLuminescence ImmunoAssay (ECLIA, Meso Scale Discovery) and digital ELISA technology (Single Molecule Array-SIMOA, Quanterix.

Functional Beta Cell Mass from Device-Encapsulated hESC-Derived Pancreatic Endoderm Achieving Metabolic Control.

Human stem cells represent a potential source for implants that replace the depleted functional beta cell mass (FBM) in diabetes patients. Human embryonic stem cell-derived pancreatic endoderm (hES-PE) can generate implants with glucose-responsive beta cells capable of reducing hyperglycemia in mice. This study with device-encapsulated hES-PE (4 × 10 cells/mouse) determines the biologic characteristics at which implants establish metabolic control during a 50-week follow-up.

Immunogenicity of human embryonic stem cell-derived beta cells.

Aims/hypothesis: To overcome the donor shortage in the treatment of advanced type 1 diabetes by islet transplantation, human embryonic stem cells (hESCs) show great potential as an unlimited alternative source of beta cells. hESCs may have immune privileged properties and it is important to determine whether these properties are preserved in hESC-derived cells.

Methods: We comprehensively investigated interactions of both innate and adaptive auto- and allo-immunity with hESC-derived pancreatic progenitor cells and hESC-derived endocrine cells, retrieved after in-vivo differentiation in capsules in the subcutis of mice.

CD99 as surface anchor for human islet endocrine cell purification.

Rat and human beta cell proteomes were quantified by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS), searching for cell surface markers. In human beta cells, CD99 (cluster of differentiation 99) was ranked among the plasma membrane proteins that combine a high molar abundance with a relative degree of selectivity for the endocrine cells of the islets of Langerhans. Therefore, the applicability of CD99 as anchor for islet endocrine cell purification was investigated.

Direct effect of glucocorticoids on glucose-activated adult rat β-cells increases their cell number and their functional mass for transplantation.

Compounds that increase β-cell number can serve as β-cell replacement therapies in diabetes. In vitro studies have identified several agents that can activate DNA synthesis in primary β-cells but only in small percentages of cells and without demonstration of increases in cell number. We used whole well multiparameter imaging to first screen a library of 1,280 compounds for their ability to recruit adult rat β-cells into DNA synthesis and then assessed influences of stimulatory agents on the number of living cells.

A combination of cytokines EGF and CNTF protects the functional beta cell mass in mice with short-term hyperglycaemia.

Aims/hypothesis: When the beta cell mass or function declines beyond a critical point, hyperglycaemia arises. Little is known about the potential pathways involved in beta cell rescue. As two cytokines, epidermal growth factor (EGF) and ciliary neurotrophic factor (CNTF), restored a functional beta cell mass in mice with long-term hyperglycaemia by reprogramming acinar cells that transiently expressed neurogenin 3 (NGN3), the current study assesses the effect of these cytokines on the functional beta cell mass after an acute chemical toxic insult.

Intralymphatic mRNA vaccine induces CD8 T-cell responses that inhibit the growth of mucosally located tumours.

The lack of appropriate mouse models is likely one of the reasons of a limited translational success rate of therapeutic vaccines against cervical cancer, as rapidly growing ectopic tumours are commonly used for preclinical studies. In this work, we demonstrate that the tumour microenvironment of TC-1 tumours differs significantly depending on the anatomical location of tumour lesions (i.e.

Development of an Enhanced Sensitivity Bead-Based Immunoassay for Real-Time In Vivo Detection of Pancreatic β-Cell Death.

There is a clinical need for plasma tests to detect and quantify the in vivo destruction of pancreatic β-cells in type 1 diabetes. We previously developed a time-resolved fluorescence immunoassay (TRFIA) to glutamate decarboxylase 65 kDa (GAD65) (GAD65-TRFIA) that was able to detect the synchronous necrotic destruction of transplanted β-cells in the hours after their infusion in the liver. This GAD65-TRFIA, however, lacked sensitivity to detect continued β-cell rejection beyond this acute phase.

Ex Vivo Expansion and Differentiation of Human and Mouse Fetal Pancreatic Progenitors Are Modulated by Epidermal Growth Factor.

A comparative analysis of mouse and human pancreatic development may reveal common mechanisms that control key steps as organ morphogenesis and cell proliferation and differentiation. More specifically, understanding beta cell development remains an issue, despite recent progress related to their generation from human embryonic and induced pluripotent stem cells. In this study, we use an integrated approach, including prospective isolation, organ culture, and characterization of intermediate stages, and report that cells from human and mouse fetal pancreas can be expanded in the long term and give rise to hollow duct-like structures in 3D cultures.

Potential of UCHL1 as biomarker for destruction of pancreatic beta cells.

Unlabelled: There is a clinical need for plasma tests for real-time detection of beta cell destruction, as surrogate endpoint in islet transplantation and immunoprevention trials in type 1 diabetes. This study reports on the use of label-free LC-MS/MS proteomics for bottom-up selection of candidate biomarkers. Ubiquitin COOH-terminal hydrolase 1 (UCHL1) was identified as abundant protein in rat and human beta cells, showing promising beta cell-selectivity, and was selected for further validation in standardized toxicity models.

Combining MK626, a novel DPP-4 inhibitor, and low-dose monoclonal CD3 antibody for stable remission of new-onset diabetes in mice.

Combining immune intervention with therapies that directly influence the functional state of the β-cells is an interesting strategy in type 1 diabetes cure. Dipeptidyl peptidase-4 (DPP-4) inhibitors elevate circulating levels of active incretins, which have been reported to enhance insulin secretion and synthesis, can support β-cell survival and possibly stimulate β-cell proliferation and neogenesis. In the current study, we demonstrate that the DPP-4 inhibitor MK626, which has appropriate pharmacokinetics in mice, preceded by a short-course of low-dose anti-CD3 generated durable diabetes remission in new-onset diabetic non-obese diabetic (NOD) mice.

Composition and function of macroencapsulated human embryonic stem cell-derived implants: comparison with clinical human islet cell grafts.

β-Cells generated from large-scale sources can overcome current shortages in clinical islet cell grafts provided that they adequately respond to metabolic variations. Pancreatic (non)endocrine cells can develop from human embryonic stem (huES) cells following in vitro derivation to pancreatic endoderm (PE) that is subsequently implanted in immune-incompetent mice for further differentiation. Encapsulation of PE increases the proportion of endocrine cells in subcutaneous implants, with enrichment in β-cells when they are placed in TheraCyte-macrodevices and predominantly α-cells when they are alginate-microencapsulated.