Microencapsulation of cells and molecular therapy of type 1 diabetes mellitus: The actual state and future perspectives between promise and progress

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Stem Cells for the Cell and Molecular Therapy of Type 1 Diabetes Mellitus (T1D) between Lights and Shadows

T1D consists of selective autoimmune killing of pancreatic islet β-cells that physiologically accomplish the task of secreting insulin on a regulated manner, in order to maintain blood glucose levels within normal range (70-140 mg/dl), under any circumstances

A comparison of lysosomal enzymes expression levels in peripheral blood of mild- and severe-Alzheimer's disease and MCI patients: implications for regenerative medicine approaches

The association of lysosomal dysfunction and neurodegeneration has been documented in several neurodegenerative diseases, including Alzheimer's Disease (AD). Herein, we investigate the association of lysosomal enzymes with AD at different stages of progression of the disease (mild and severe) or with mild cognitive impairment (MCI). We conducted a screening of two classes of lysosomal enzymes: glycohydrolases (\u3b2-Hexosaminidase, \u3b2-Galctosidase, \u3b2-Galactosylcerebrosidase, \u3b2-Glucuronidase) and proteases (Cathepsins S, D, B, L) in peripheral blood samples (blood plasma and PBMCs) from mild AD, severe AD, MCI and healthy control subjects. We confirmed the lysosomal dysfunction in severe AD patients and added new findings enhancing the association of abnormal levels of specific lysosomal enzymes with the mild AD or severe AD, and highlighting the difference of AD from MCI. Herein, we showed for the first time the specific alteration of \u3b2-Galctosidase (Gal), \u3b2-Galactosylcerebrosidase (GALC) in MCI patients. It is notable that in above peripheral biological samples the lysosomes are more sensitive to AD cellular metabolic alteration when compared to levels of A\u3b2-peptide or Tau proteins, similar in both AD groups analyzed. Collectively, our findings support the role of lysosomal enzymes as potential peripheral molecules that vary with the progression of AD, and make them useful for monitoring regenerative medicine approaches for AD

Microencapsulation of cells and molecular therapy of type 1 diabetes mellitus: The actual state and future perspectives between promise and progress

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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. (C) 2011 Elsevier Ltd. All rights reserved

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

Utilization of a Commercial 3D Printer for the Construction of a Bio-Hybrid Device Based on Bioink and Adult Human Mesenchymal Cells

The biofabrication of three-dimensional scaffolds using 3D printers and cell-containing bioinks is very promising. A wide range of materials and bioink compositions are being created and tested for cell viability and printability in order to satisfy the requirements of a bioink. This methodology has not still achieved technological maturity, and the actual costs mean that they are often inaccessible for researchers, consequently lowering the development and extending the required times. This research aims to apply this methodology on a laboratory scale by re-adapting a commercial 3D printer, consequently lowering the costs and energy impacts, and, at the same time, ensuring a level of accuracy extremely close to the currently adopted devices and, more in general, suitable for the scopes of the research. To accomplish this, we assembled a biomimetic scaffold made of human Umbilical Cord Matrix Stem Cells (hUCMS), cellulose, and alginate. Various molds were used to produce 3D scaffolds of different sizes. After bioprinting, cell viability was analyzed using ethidium bromide and fluorescein diacetate, and a histological stain was used to evaluate cell and bioink morphology. All of the examined bioinks had a uniform final 3D structure and were stable, easily printable, and procedure-adapted. Up until 21 days of culture, the bioinks remained unaltered and were simple to manipulate. After 7 and 21 days of cell culture, the hUCMS in the cellulose/alginate-based bioinks exhibited cell viabilities of 95% and 85%, respectively. The cells did not present with a fibroblast-like shape but appeared to be round-shaped and homogeneously distributed in the 3D structure. Biomimetic bioink, which is based on cellulose and alginate, is an appropriate hydrogel for 3D bioprinting. This preliminary work illustrated the potential use of these two biomaterials for the 3D bioprinting of mesenchymal stem cells

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

Surface Hydrophilicity of Poly(l-Lactide) Acid Polymer Film Changes the Human Adult Adipose Stem Cell Architecture

Current knowledge indicates that the molecular cross-talk between stem cells and biomaterials guides the stem cells’ fate within a tissue engineering system. In this work, we have explored the effects of the interaction between the poly(l-lactide) acid (PLLA) polymer film and human adult adipose stem cells (hASCs), focusing on the events correlating the materials’ surface characteristics and the cells’ plasma membrane. hASCs were seeded on films of pristine PLLA polymer and on a PLLA surface modified by the radiofrequency plasma method under oxygen flow (PLLA+O2). Comparative experiments were performed using human bone-marrow mesenchymal stem cells (hBM-MSCs) and human umbilical matrix stem cells (hUCMSCs). After treatment with oxygen-plasma, the surface of PLLA films became hydrophilic, whereas the bulk properties were not affected. hASCs cultured on pristine PLLA polymer films acquired a spheroid conformation. On the contrary, hASCs seeded on PLLA+O2 film surface maintained the fibroblast-like morphology typically observed on tissue culture polystyrene. This suggests that the surface hydrophilicity is involved in the acquisition of the spheroid conformation. Noteworthy, the oxygen treatment had no effects on hBM-MSC and hUCMSC cultures and both stem cells maintained the same shape observed on PLLA films. This different behavior suggests that the biomaterial-interaction is stem cell specific