Human induced pluripotent stem cells (hiPSC), enveloped in elastin-like recombinamers for cell therapy of type 1 diabetes mellitus (T1D): preliminary data.

Introduction: Therapeutic application and study of type 1 diabetes disease could benefit from the use of functional ß islet-like cells derived from human induced pluripotent stem cells (hiPSCs). Considerable efforts have been made to develop increasingly effective hiPSC differentiation protocols, although critical issues related to cost, the percentage of differentiated cells that are obtained, and reproducibility remain open. In addition, transplantation of hiPSC would require immunoprotection within encapsulation devices, to make the construct invisible to the host's immune system and consequently avoid the recipient's general pharmacologic immunosuppression. Methods: For this work, a microencapsulation system based on the use of "human elastin-like recombinamers" (ELRs) was tested to envelop hiPSC. Special attention was devoted to in vitro and in vivo characterization of the hiPSCs upon coating with ERLs. Results and Discussion: We observed that ELRs coating did not interfere with viability and function and other biological properties of differentiated hiPSCs, while in vivo, ELRs seemed to afford immunoprotection to the cell grafts in preliminary in vivo study. The construct ability to correct hyperglycemia in vivo is in actual progress.

Emerging of a new CD3+CD31HCD184+ tang cell phenothype in Sjögren's syndrome induced by microencapsulated human umbilical cord matrix-derived multipotent stromal cells.

Background: Sjögren's syndrome (SS) is an autoimmune disease hallmarked by infiltration and destruction of exocrine glands. Currently, there is no therapy that warrants full recovery of the affected tissues. Umbilical cord-derived multipotent stromal cells, microincapsulated in an endotoxin-free alginate gel (CpS-hUCMS), were shown to modulate the inflammatory activity of PBMCs in SS patients in vitro, through release of soluble factors (TGFß1, IDO1, IL6, PGE2, VEGF). These observations led us to set up the present study, aimed at defining the in vitro effects of CpS-hUCMS on pro- and anti-inflammatory lymphocyte subsets involved in the pathogenesis of SS. Methods and results: Peripheral blood mononuclear cells (PBMCs) upon collection from SS patients and matched healthy donors, were placed in co-culture with CpS-hUCMS for five days. Cellular proliferation and T- (Tang, Treg) and B- (Breg, CD19+) lymphocyte subsets were studied by flow cytometry, while Multiplex, Real-Time PCR, and Western Blotting techniques were employed for the analysis of transcriptome and secretome. IFNγ pre-treated hUCMS were assessed with a viability assay and Western Blotting analysis before co-culture. After five days co-culture, CpS-hUCMS induced multiple effects on PBMCs, with special regard to decrease of lymphocyte proliferation, increase of regulatory B cells and induction of an angiogenic T cell population with high expression of the surface marker CD31, that had never been described before in the literature. Conclusion: We preliminarily showed that CpS-hUCMS can influence multiple pro- and anti-inflammatory pathways that are deranged in SS. In particular, Breg raised and a new Tang phenothype CD3+CD31HCD184+ emerged. These results may considerably expand our knowledge on multipotent stromal cell properties and may open new therapeutic avenues for the management of this disease, by designing ad hoc clinical studies.

Microencapsulated Wharton Jelly-derived adult mesenchymal stem cells as a potential new therapeutic tool for patients with COVID-19 disease: an in vitro study.

BACKGROUND: The recent newly appeared Coronavirus disease (COVID-19), caused by an enveloped RNA virus named "severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)", is associated with severe respiratory morbidity and mortality. Recent studies have shown that lymphopenia and a cytokine mass release represent important pathogenic features, with clinical evidence of dyspnea and hypoxemia, often leading to acute respiratory distress syndrome (ARDS), in severely ill patients, with a high death toll. Currently, stem cells are actively being investigated for their potential use in many "untreatable" diseases. In this regard and in particular, Mesenchymal Stem Cells (MSC), due to their intrinsic features, including either ability to impact on regulation of the immune system, or association with both anti-viral and anti-inflammatory properties, or potential for differentiation into several cell lineages, have become a promising tool for cell and molecular-based therapies. On this background, we wished to explore whether human umbilical cord-derived mesenchymal stem cells (hUCMS) would represent a potential viable therapeutic approach for the management of critically ill COVID19 patients. METHODS: We tested the hUCMS effects on peripheral blood mononuclear cell (PBMCs) retrieved from patients with COVID19 (Ethical Committee CEAS Umbria, Italy CER N°3658/20 7, May, 2020), both as free cell monolayers and after envelopment in sodium alginate microcapsules. Both cell systems, after priming with IFN-γ, proved able to produce several immunomodulatory molecules such as IDO1 and HLAG5, although only the microencapsulated hUCMS were associated with massive and dose-dependent production of these factors. RESULTS: The microencapsulated hUCMS improved allo-suppression in mixed lymphocytes reactions (MLRs), while also blunting T helper 1 and T helper 17 responses, that are involved with the cytokine storm and greatly contribute to the patient death. Moreover, we observed that both free and microencapsulated hUCMS permitted 5 days survival of in vitro culture maintained PBMCs extracted from very ill patients. CONCLUSION: We have provided evidence that microencapsulated hUCMS in vitro, seem to represent a powerful tool to impact on several immune pathways, clearly deranged in COVID19 patients. Further study is necessary to begin in vivo assessment of this experimental system, upon determining both, the most appropriate time of the disease onset for intervention, and cell dosage/patient of our experimental product.

Co-microencapsulation of human umbilical cord-derived mesenchymal stem and pancreatic islet-derived insulin producing cells in experimental type 1 diabetes.

INTRODUCTION: Post-partum umbilical cord Wharton Jelly-derived adult mesenchymal stem cells (hUCMS) hold anti-inflammatory and immunosuppressive properties. Human pancreatic islet-derived progenitor cells (hIDC) may de-differentiate, and subsequently re-differentiate into insulin producing cells. The two cell types share common molecules that facilitate their synergistic interaction and possibly crosstalk, likely useful for the cell therapy of type 1 diabetes (T1D). MATERIALS AND METHODS: Upon microencapsulation in sodium alginate (AG), hUCMS and hIDC were able to form cell co-aggregates that looked well integrated and viable. We then grafted microencapsulated hUCMS/hIDC co-aggregates into non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice, and observed an acquired ability of cells to produce and store hormones. Finally, we transplanted these biohybrid constructs into NOD mice with recent onset, spontaneous overt diabetes, observing a decline of blood glucose levels. RESULTS: In vitro, we have shown that hUCMS inhibited proliferation of allogeneic polymorphonuclear blood cells from patients with T1D, while promoting expansion of FoxP3+ Tregs. Reversal of hyperglycemia in diabetic NODs seems to suggest that hUCMS and hIDC, upon co-microencapsulation, anatomically and functionally synergized to accomplish two goals: maintain tracer insulin output by hIDC, while exploting the immunoregulatory properties of hUCMS. CONCLUSION: We have gathered preliminary evidence that the two adult stem cell types within AG microcapsules, may synergistically promote tracer insulin production, while "freezing" the autoimmune disease process, and help reversal of the recent onset hyperglycemia in a spontaneous, autoimmune rodent model of diabetes, the NOD mouse, with no need for pharmacologic immunosuppression.

Microencapsulated G3C Hybridoma Cell Graft Delays the Onset of Spontaneous Diabetes in NOD Mice by an Expansion of Gitr+ Treg Cells.

As an alternative to lifelong insulin supplementation, potentiation of immune tolerance in patients with type 1 diabetes could prevent the autoimmune destruction of pancreatic islet ß-cells. This study was aimed to assess whether the G3c monoclonal antibody (mAb), which triggers the glucocorticoid-induced TNFR-related (Gitr) costimulatory receptor, promotes the expansion of regulatory T cells (Tregs) in SV129 (wild-type) and diabetic-prone NOD mice. The delivery of the G3c mAb via G3C hybridoma cells enveloped in alginate-based microcapsules (G3C/cps) for 3 weeks induced Foxp3+ Treg-cell expansion in the spleen of wild-type mice but not in Gitr-/- mice. G3C/cps also induced the expansion of nonconventional Cd4+Cd25-/lowFoxp3lowGitrint/high (GITR single-positive [sp]) Tregs. Both Cd4+Cd25+GitrhighFoxp3+ and GITRsp Tregs (including also antigen-specific cells) were expanded in the spleen and pancreas of G3C/cps-treated NOD mice, and the number of intact islets was higher in G3C/cps-treated than in empty cps-treated and untreated animals. Consequently, all but two G3C/cps-treated mice did not develop diabetes and all but one survived until the end of the 24-week study. In conclusion, long-term Gitr triggering induces Treg expansion, thereby delaying/preventing diabetes development in NOD mice. This therapeutic approach may have promising clinical potential for the treatment of inflammatory and autoimmune diseases.

Engineered Alginate Microcapsules for Molecular Therapy Through Biologic Secreting Cells.

Continuous delivery of monoclonal antibodies (mAbs) at low concentrations may be helpful in the management of several chronic, especially autoimmune diseases. A possible approach to employ mAbs therapy in vivo, in the absence of in vitro manipulations, could be graft of microcapsules containing mAb-secreting hybridoma cells (HY). Sodium alginate (AG) is a polymeric saccharide that permits simple fabrication of microcapsules that are biocompatible and prevent immune recognition of encapsulated cells, upon graft, by the host's immune system. However, at present, AG-based microcapsules are usually impermeable to large molecules. The aim of this study was to engineer the membrane of AG-based microcapsules, to make it permeable to larger molecular weight classes of mAbs. To this end, we have prepared a new AG-based membrane, using standard reagents already in use, but following different coating procedures and molar ratios. In particular, we fabricated a new capsular membrane permeable to IgM synthesized by the HY cell line, G3C. Morphologic structural and ultrastructural analysis of the new membranes before and after intraperitoneal transplant, in conjunction with IgM outflow secretory kinetics underwent both, in vitro and in vivo assessments. While allowing immunoprotection of the enveloped HY, as demonstrated by the absence of any inflammatory response, the microcapsules permitted G3c mAb egress, on a regulated delivery kinetics. HY viability persisted, upon transplant, for long time periods. In summary, the new AG-based microcapsules allow delivery of big molecules out of the capsules, while protecting the enveloped HY from the host's immune system. These microcapsules could apply to implant cells producing fully active large molecules without the need of time- and cost expensive procedures to purify them.

Remission of hyperglycemia in spontaneously diabetic NOD mice upon transplant of microencapsulated human umbilical cord Wharton jelly-derived mesenchymal stem cells (hUCMS).

BACKGROUND: Our previous in vitro demonstration of the immunoregulatory effects of microencapsulated hUCMS on human peripheral blood mononuclear cells (PBMCs) extracted from patients with recent onset, type 1 diabetes mellitus (DM), prompted us to test our product for xenograft (TX) in non obese diabetic (NOD) mice with spontaneous DM. METHODS: We transplanted microencapsulated hUCMS into the peritoneal cavity of NOD mice with either severe or mild DM. Blood glucose (BG) levels were monitored following TX, in either basal or upon glucose stimulation. RESULTS: Only the NODs with mild DM showed full and sustained remission of hyperglycemia throughout 216 days post-TX, unlike recipients with severe DM, where no remission of hyperglycemia was attained, as reflected by erratic BG levels at all times. CONCLUSIONS: These data suggest that the stage of DM disease process in NOD mice, reflecting steady decline of residual b-cell mass, plays a pivotal role in determining the success of this cell therapy approach for treatment of DM.

Design of a nanocomposite substrate inducing adult stem cell assembly and progression toward an Epiblast-like or Primitive Endoderm-like phenotype via mechanotransduction.

This work shows that the active interaction between human umbilical cord matrix stem cells and Poly (l-lactide)acid (PLLA) and PLLA/Multi Walled Carbon Nanotubes (MWCNTs) nanocomposite films results in the stem cell assembly as a spheroid conformation and affects the stem cell fate transition. We demonstrated that spheroids directly respond to a tunable surface and the bulk properties (electric, dielectric and thermal) of plain and nanocomposite PLLA films by triggering a mechanotransduction axis. This stepwise process starts from tethering of the cells' focal adhesion proteins to the surface, together with the adherens junctions between cells. Both complexes transmit traction forces to F-Actin stress fibres that link Filamin-A and Myosin-IIA proteins, generating a biological scaffold, with increased stiffening conformation from PLLA to PLLA/MWCNTs, and enable the nucleoskeleton proteins to boost chromatin reprogramming processes. Herein, the opposite expression of NANOG and GATA6 transcription factors, together with other lineage specification related proteins, steer spheroids toward an Epiblast-like or Primitive Endoderm-like lineage commitment, depending on the absence or presence of 1 wt% MWCNTs, respectively. This work represents a pioneering effort to create a stem cell/material interface that can model the stem cell fate transition under growth culture conditions.

Human Umbilical Cord Wharton Jelly-Derived Adult Mesenchymal Stem Cells, in Biohybrid Scaffolds, for Experimental Skin Regeneration.

The ultimate goal for skin tissue engineering is to regenerate skin lesions to allow the full restoration of morphological and functional properties as what they were before injury. To this end, we have assembled a new prototype of a biomimetic human umbilical cord adult mesenchymal stem cell (hUCMS)/fibrin-based scaffold. We have fully characterized the proposed dermal equivalent (DE) in vitro, to assess morphological, functional, and biological properties of the encased cells. We transplanted DE subcutaneously into immunocompetent rodents, to verify its full biocompatibility. Finally, we studied DE graft effects on full-thickness wounds, in immunocompetent mice to demonstrate its capability to drive the healing process in the absence of significant scarring tissue. The excellent outcome of these in vivo studies fuels hope that this new approach, based on a biohybrid DE, may be applied to the operative treatment of skin lesions (i.e., diabetic foot ulcers and burns) in man.

Functional Profiles of Human Umbilical Cord-Derived Adult Mesenchymal Stem Cells in Obese/Diabetic Versus Healthy Women.

BACKGROUND: Adult human mesenchymal stem cells retrieved, from the post-partum human umbilical cord Wharton jelly (hUCMS), have recently gained growing interest due to their morphological and functional properties. OBJECTIVE: The main purpose of our work was to examine morphology and functional properties of hUCMS retrieved from healthy women as compared to those with obesity, or gestational or type 2 diabetes mellitus, under fair metabolic control. Possible differences between groups could shed light into the potential use of these cells for the cell therapy of a variety of diseases, regardless of the obesity/diabetes status of the donor mothers. Additionally, information on how the maternal disease may affect the cord-derived stem cells, hence possibly newborn children would be important. METHOD: We have studied obese/diabetic or normal donor post-partum umbilical cord-derived hUCMS, either in basal or during differentiation protocols into several cell phenotypes and the definitive endoderm. Immunomodulatory properties of these cells, in terms of inhibition of activated lymphocyte proliferation, also was examined. RESULTS: According to our preliminary results, there are functional differences, as assessed by cell and molecular assays, in terms of both, differentiation and immunomodulatory potential, between the cells derived from normal as compared to obese/diabetic mothers. CONCLUSION: The findings seemingly indicate that the uterine environment of obese/diabetic mothers is quite distant from normal, regardless of metabolic control. Hence hUCMS extracted from obese/diabetic mothers do not appear to be suitable for cell therapy clinical protocols but more studies are required.

Restoration of t cell substes of patients with type 1 diabetes mellitus by microencapsulated human umbilical cord Wharton jelly-derived mesenchymal stem cells: An in vitro study.

Human umbilical cord Wharton jelly-derived mesenchymal stem cells (hUCMS) might apply to treating chronic autoimmune disorders, as already shown for Sjögren's syndrome, including type 1 diabetes mellitus (T1D). Since naked hUCMS grafts encountered restraints, we enveloped hUCMS, within immunoisolatory microcapsules (CpS-hUCMS), made of our endotoxin-free, clinical grade alginate. We then examined the vitro effects of interferon (IFN)-γ-pretreated CpS-hUCMS on Th17 and Treg of T1D patients (n=15) and healthy controls (n=10). Peripheral blood mononuclear cells (PBMCs) were co-cultured with PBMC/CpS-hUCMS: lymphocyte proliferation was assessed by carboxyfluorescein succinimidyl esther (CFSE) dilution assay, and phenotypic analysis of regulatory and effector Tc was also performed. Cytokine expression was performed by bead array and qPCR on IFN-γ-pretreated hUCMS before PBMCs co-culture. CpS-hUCMS restored a correct Treg/Th17 ratio, relevant to the T1D disease process. In summary, we have preliminarily developed a new biohybrid system, associated with immunoregulatory properties, that is ready for in vivo application.

Insights in Behavior of Variably Formulated Alginate-Based Microcapsules for Cell Transplantation.

Alginate-based microencapsulation of live cells may offer the opportunity to treat chronic and degenerative disorders. So far, a thorough assessment of physical-chemical behavior of alginate-based microbeads remains cloudy. A disputed issue is which divalent cation to choose for a high performing alginate gelling process. Having selected, in our system, high mannuronic (M) enriched alginates, we studied different gelling cations and their combinations to determine their eventual influence on physical-chemical properties of the final microcapsules preparation, in vitro and in vivo. We have shown that used of ultrapure alginate allows for high biocompatibility of the formed microcapsules, regardless of gelation agents, while use of different gelling cations is associated with corresponding variable effects on the capsules' basic architecture, as originally reported in this work. However, only the final application which the capsules are destined to will ultimately guide the selection of the ideal, specific gelling divalent cations, since in principle there are no capsules that are better than others.

In vitro immunomodulatory effects of microencapsulated umbilical cord Wharton jelly-derived mesenchymal stem cells in primary Sjögren's syndrome.

OBJECTIVE: Human umbilical cord Wharton jelly-derived mesenchymal stem cells (hUCMS) are easy to retrieve in bulk. They may interact with immune cells by either cell contact or soluble factors. Little evidence is currently available on potential therapeutic application of hUCMS to systemic autoimmune disorders such as primary SS (pSS). We have recently developed an endotoxin-free alginate gel that can be used to microencapsulate different cell types for graft into non-immunosuppressed hosts. We aimed to assess the in vitro effects of IFN-γ-pretreated microencapsulated (CpS)-hUCMS on T cells of pSS. METHODS: Ten pSS patients and 10 healthy donors were selected. Peripheral blood mononuclear cells (PBMCs) were obtained from venous blood to establish co-cultures with CpS-hUCMS. Lymphocyte proliferation and phenotypic analysis was performed by flow cytometry and real-time PCR on IFN-γ-pretreated hUCMS was performed before PBMCs co-culture. RESULTS: We found that CpS-hUCMS suppress pSS T cell proliferation and restore the Treg/Th17 ratio, thereby possibly positively impacting the pSS disease process. CONCLUSION: We have developed a new biohybrid drug delivery system that now waits for clinical application in autoimmune diseases, including pSS.

Treatment of diabetes mellitus with microencapsulated fetal human liver (FH-B-TPN) engineered cells.

Transplantation of whole human pancreases or isolated islets into patients with type 1 diabetes mellitus has been severely hampered by the scarcity of cadaveric human donor organs, which mandates search for insulin producing cells/tissue source alternatives. Recent progress in stem cell biology has started looking into functionally competent, insulin-secreting progenitor cells. It had been previously observed that induced expression of the ß-cell transcriptional factor of the pancreatic and duodenal homeobox gene1 (PDX1), in human hepatocytes, may activate multiple features of the ß-cell phenotype. These "FH-B-TPN" cells were shown to release insulin in response to physiological glucose stimulation both, in vitro and in vivo. However, because FH-B-TPNs lack the expression of a number of ß-cell or non ß-cell genes, and are associated with low insulin content, we aimed to determine whether these cells, upon physical manipulation and envelopment within "clinical grade" alginate-based microcapsules, would reverse hyperglycemia after graft into diabetic animal models.

The functional performance of microencapsulated human pancreatic islet-derived precursor cells.

We have examined long-term cultured, human islet-derived stem/precursor cells (hIPC). Whole human islets (HI) were obtained by multi-enzymatic digestion of cadaveric donor pancreases, plated on tissue flasks, and allowed to adhere and expand for several in vitro passages, in order to obtain hIPC. We detected specific stem cell markers (Oct-4, Sox-2, Nanog, ABCG2, Klf-4, CD117) in both intact HI and hIPC. Moreover, hIPC while retaining the expression of Glut-2, Pdx-1, CK-19, and ICA-512, started re-expressing Ngn3, thereby indicating acquisition of a specific pancreatic islet beta cell-oriented phenotype identity. The intrinsic plasticity of hIPC was documented by their ability to differentiate into various germ layer-derived cell phenotypes (ie, osteocytic, adipocytic and neural), including endocrine cells associated with insulin secretory capacity. To render hIPC suitable for transplantation we have enveloped them within our highly purified, alginate-based microcapsules. Upon intraperitoneal graft in NOD/SCID mice we have observed that the microcapsules acted as three-dimensional niches favouring post-transplant hIPC differentiation and acquisition of beta cell-like functional competence.

New simple and rapid method for purification of mesenchymal stem cells from the human umbilical cord Wharton jelly.

We have developed a simple and rapid method for isolation of human umbilical cord matrix stem cells (hUCMS). The umbilical cord contains a virtual inexhaustible source of adult stem cells. We have substantially modified, simplified, and improved previously reported hUCMS isolation procedures in terms of either used enzyme type, or digestion time, and substantially enhanced the final product yield and purity. The isolated hUCMS were positive for CD90, CD117, and SCF, and negative for CD31 and CD45 surface markers. mRNA and related proteins (i.e., Sox2, Oct4a, Nanog, ABCG2, and c-Myc) that coincide with an uncommitted cell status also were detected. hUCMS express genes and proteins for CD90 and Nestin that are associated with mesenchymal stem cells, as well as other genes that specifically relate to different embryonic germ layers, namely, Vimentin, Sox7, Sox17, FoxA2, E-cadherin, and N-cadherin. hUCMS showed multilineage cell differentiation potential into adipogenic, osteogenic, and neural cell phenotypes, under the influence of lineage-specific, differentiation culture media. Moreover, the basal expression of endocrine cell markers makes these cells seemingly suitable for endocrine cell phenotype differentiation. Noteworthy, Activin A induced hUCMS to acquire definitive endoderm cell markers.