14-3-3ε protein-loaded 3D hydrogels favor osteogenesis

3D printing has emerged as vanguard technique of biofabrication to assemble cells, biomaterials and biomolecules in a spatially controlled manner to reproduce native tissues. In this work, gelatin methacrylate (GelMA)/alginate hydrogel scaffolds were obtained by 3D printing and 14-3-3ε protein was encapsulated in the hydrogel to induce osteogenic differentiation of human adipose-derived mesenchymal stem cells (hASC). GelMA/alginate-based grid-like structures were printed and remained stable upon photo-crosslinking. The viscosity of alginate allowed to control the pore size and strand width. A higher viscosity of hydrogel ink enhanced the printing accuracy. Protein-loaded GelMA/alginate-based hydrogel showed a clear induction of the osteogenic differentiation of hASC cells. The results are relevant for future developments of GelMA/alginate for bone tissue engineering given the positive effect of 14-3-3ε protein on both cell adhesion and proliferation.Fil: Aldana, Ana Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Uhart, Marina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mendoza. Instituto de Histologia y Embriologia de Mendoza Dr. Mario H. Burgos. Grupo Vinculado de Investigacion y Desarrollo Biotecnologico Aplicado Al Diagnostico Al Ihem | Universidad Nacional de Cuyo. Facultad de Ciencias Medicas. Instituto de Histologia y Embriologia de Mendoza Dr. Mario H. Burgos. Grupo Vinculado de Investigacion y Desarrollo Biotecnologico Aplicado Al Diagnostico Al Ihem.; ArgentinaFil: Abraham, Gustavo Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Bustos, Diego Martin. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mendoza. Instituto de Histologia y Embriologia de Mendoza Dr. Mario H. Burgos. Grupo Vinculado de Investigacion y Desarrollo Biotecnologico Aplicado Al Diagnostico Al Ihem | Universidad Nacional de Cuyo. Facultad de Ciencias Medicas. Instituto de Histologia y Embriologia de Mendoza Dr. Mario H. Burgos. Grupo Vinculado de Investigacion y Desarrollo Biotecnologico Aplicado Al Diagnostico Al Ihem.; ArgentinaFil: Boccaccini, Aldo Roberto. Universitat Erlangen-Nuremberg; Alemani

Investigating the Vascularization of Tissue-Engineered Bone Constructs Using Dental Pulp Cells and 45S5 Bioglass(®) Scaffolds.

Identification of a suitable cell source combined with an appropriate 3D scaffold is an essential prerequisite for successful engineering of skeletal tissues. Both osteogenesis and angiogenesis are key processes for bone regeneration. This study investigated the vascularization potential of a novel combination of human dental pulp stromal cells (HDPSCs) with 45S5 Bioglass(®) scaffolds for tissue-engineered mineral constructs in vivo and in vitro. 45S5 Bioglass scaffolds were produced by the foam replication technique with the standard composition of 45 wt% SiO2, 24.5 wt% Na2O, 24.5 wt% CaO, and 6 wt% P2O5. HDPSCs were cultured in monolayers and on porous 45S5 Bioglass scaffolds under angiogenic and osteogenic conditions for 2-4 weeks. HDPSCs expressed endothelial gene markers (CD34, CD31/PECAM1, and VEGFR2) under both conditions in the monolayer. A combination of HDPSCs with 45S5 Bioglass enhanced the expression of these gene markers. Positive immunostaining for CD31/PECAM1 and VEGFR2 and negative staining for CD34 supported the gene expression data, while histology revealed evidence of endothelial cell-like morphology within the constructs. More organized tubular structures, resembling microvessels, were seen in the constructs after 8 weeks of implantation in vivo. In conclusion, this study suggests that the combination of HDPSCs with 45S5 Bioglass scaffolds offers a promising strategy for regenerating vascularized bone grafts

When Electrospun Fiber Support Matters: In Vitro Ovine Long-Term Folliculogenesis on Poly (Epsilon Caprolactone) (PCL)-Patterned Fibers

Current assisted reproduction technologies (ART) are insufficient to cover the slice of the population needing to restore fertility, as well as to amplify the reproductive performance of domestic animals or endangered species. The design of dedicated reproductive scaffolds has opened the possibility to better recapitulate the reproductive 3D ovarian environment, thus potentially innovating in vitro folliculogenesis (ivF) techniques. To this aim, the present research has been designed to compare ovine preantral follicles in vitro culture on poly(epsilon-caprolactone) (PCL)-based electrospun scaffolds designed with different topology (Random vs. Patterned fibers) with a previously validated system. The ivF performances were assessed after 14 days under 3D-oil, Two-Step (7 days in 3D-oil and on scaffold), or One-Step PCL protocols (14 days on PCL-scaffold) by assessing morphological and functional outcomes. The results show that Two- and One-Step PCL ivF protocols, when performed on patterned scaffolds, were both able to support follicle growth, antrum formation, and the upregulation of follicle marker genes leading to a greater oocyte meiotic competence than in the 3D-oil system. In conclusion, the One-Step approach could be proposed as a practical and valid strategy to support a synergic follicle-oocyte in vitro development, providing an innovative tool to enhance the availability of matured gametes on an individual basis for ART purposes

Apatite mineralization process from silicocarnotite bioceramics: mechanism of crystal growth and maturation

A mechanism for the formation and crystallization processes of bone-like apatite grown on non-stoichiometric silicocarnotite (SC) is here proposed. Single-phase SC powders and ceramics were obtained from fixed mixtures of hydroxyapatite and bioactive glass 45S5. The bioactive behavior of SC was assessed by immersion in Hank´s solution at different times. Afterward, a systematic theoretical-experimental study of the structural properties at the micro and nanoscale using TEM was performed and correlated with SEM, EDX, XRD, and Raman techniques to determine the apatite mineralization process from the SC phase. The initial stage of apatite formation from SC was identified as the hydration and further polymerization of silanol groups, resulting in a silica-based hydrogel, which plays a critical role in the ionic exchange. As a result of the adsorption of ionic species from the medium into the silica-based hydrogel, the precipitation of crystalline apatitic structures starts through the emergence of newly formed SC nanocrystals, which act as a template for the crystallization process of a substituted apatite with SC-like structure. Then, due to the polymorphism between SC and HAp structures, the apatite layer retains the SC periodic arrangement following an epitaxial-like growth mechanism. Identification of the apatite layer formation mechanism is critical to understand its physical and chemical properties, which controls the long-term dissolution/precipitation rate of bioactive materials and their performance in the biological environment

The pO-Index and R Ratio Gap Methods for the Assessment of Corrosion Risk in Refractory Materials in Contact with Glass Melts

Corrosion of refractories used in glass melting technology is a complex phenomenon involving chemical wear (corrosion) and physical/mechanical wear (such as erosion and abrasion) processes as well as thermal shock and spalling. Besides the complexity in the hydrodynamics of a molten silicate bath with which refractory materials are in contact, refractories are polycrystalline heterogeneous materials containing a relatively high porosity. Pores are centers for accelerated corrosion, spalling, and penetration by the hot liquid. In this work, a corrosion study of aluminosilicate refractory crucibles by chromium and calcium oxides during the melting of Cr-containing soda lime glasses as a function of temperature (1400°–1500°C) and glass basicity has been performed. The features and mechanism of the corrosion process were compared and analyzed as a function of glass acidobasicity (pO-index) and of the ratio of network-dwelling cations to A13+ cations (R). The advantage of the pO-index and ΔR gap methods to assess refractory corrosion risk as a function of the acidobasicity differential between the refractory glassy phase and the glass melt was demonstrated. The change of the concentrations of glass constituents was monitored by ICP analysis of glass samples and correlated to the observed extent of corrosion. The crystalline composition and microstructure of the refractory materials before and after being corroded were studied by XRD analyses and SEM. Cr-doped corundum was found to be the main crystalline phase in the refractory microstructure and other mixed phases with chromium and aluminum and/or silica, which formed at the boundary layer (interface) between the glasses and the aluminosilicate refractory, were identified. The results provide a useful guide to the selection of refractory materials for application in glass and glass–ceramic manufacture in terms of their corrosion risk

Efectos de vidrios bioactivos sobre angiogénesis y neovascularización de scaffolds para ingeniería tisular

La nueva generación de materiales bioactivos para ingeniería tisular comprende a aquellos materiales biodegradables que tienen la capacidad de estimular respuestas celulares específicas a nivel molecular. Existe evidencia experimental reciente que muestra que los vidrios bioactivos basados en composiciones de silicato y/o los iones liberados a partir de los mismos estimularían la formación de nuevos vasos sanguíneos (angiogénesis) en estructuras porosas (scaffolds) para aplicaciones en regeneración de tejidos. En el presente capítulo se discutirán los efectos proangiogénicos in vitro e in vivo de los vidrios bioactivos, así como los resultados logrados con la utilización de nano y/o micropartículas de vidrio bioactivo en la fabricación de nuevos biomateriales compuestos factibles de ser utilizados en medicina regenerativa e ingeniería de tejidos que requieran un alto grado de vascularización.Fil: Gorustovich Alonso, Alejandro Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Haro Durand, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Boccaccini, Aldo Roberto. Universidad Católica de Salta; Argentin

Effect of benign solvents composition on poly(ε-caprolactone) electrospun fiber properties

Green electrospinning is a flourishing trend in the field of electrospinning (ES) of polymeric/composite materials for biomedical applications. The use of non-toxic solvents instead of the most commonly used solvents in electrospinning is needed to avoid the possible presence toxic solvents traces in the electrospun mats, enhancing their cytocompatibility. It was found that a single solvent or solvent mixtures have a critical role in fiber formation and properties. In this work, fibers in the micro/nanoscale were obtainedby electrospinning technique from different poly(e-caprolactone) (PCL) solutions. Benign solvents (i.e. acetic and formic acids, water and their mixtures) and standard organic solvents for ES (i.e. chloroform)were explored in order to compare the fiber characteristics and properties. Morphology, size, crystallinity, thermal and polymer stability of fibers were analyzed. The obtained results showed the suitability of the use of benign solvents for ES, highlighting that for the use of formic acid the degradation of PCL should be taken into consideration.Fil: Bongiovanni Abel, Silvestre Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Liverani, Liliana. Universitat Erlangen-Nuremberg; AlemaniaFil: Boccaccini, Aldo Roberto. Universitat Erlangen-Nuremberg; AlemaniaFil: Abraham, Gustavo Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin

Bioactive glasses for soft tissue engineering applications

In the last few years the usage of bioactive glasses as scaffolds for soft tissue engineering has been investigated more thoroughly. The reason for the boost in interest are the attractive properties bioactive glasses offer including bioactivity as well as antibacterial, angiogenic and hemostatic properties. So far, most research efforts have focussed on applications for repairing skin and nerve tissue although there have been interesting developments in other fields including lung and intestines, which could potentially benefit a large group of patients but more studies are required. Three comprehensive reviews on this topic have been published recently, so this chapter will mainly focus on the latest relevant published research. There are a great number of patents registered for the use of bioactive glass for hard tissue engineering, however, recently patents detailing the use of bioactive glass for soft tissue engineering applications have been filed, which open the way to market bioactive glasses for the restoration of soft tissues. The angiogenic effect of bioactive glasses is of great interest for tissue engineering applications in general and in particular for soft tissue engineering, hence the third part of this chapter will detail the latest research on the angiogenic properties of bioactive glasses.Fil: Miguez Pacheco, Valentina. Universitat Erlangen Nuremberg; AlemaniaFil: Gorustovich Alonso, Alejandro Adrian. Universidad Católica de Salta; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingenieria "Hilario Fernandez Long". Grupo Vinculado al Intecin - Grupo Interdisciplinario en Materiales; ArgentinaFil: Boccaccini, Aldo Roberto. Universitat Erlangen Nuremberg; AlemaniaFil: Roether, Judith A.. Universitat Erlangen Nuremberg; Alemani