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Simple Summary: Two-dimensional (2D) models are unable to mimic the intricacies of the reaction in the natural tumor microenvironment to the irradiation, biological and architectural complexity, or dynamic nature of the many tissues. These features can be recreated using a decellularized extracellular matrix (ECM), such as bioscaffolds. We hypothesized that bioscaffolds can be a feasible and effective three-dimensional (3D) model, worthwhile also for radiobiological aims. To test our hypothesis, two cell lines (HMV-II and PANC-1) were seeded in decellularized porcine liver-derived scaffolds and irradiated with carbon ions (high-LET irradiation) and photons (low-LET irradiation). For the first time in the literature, we found that the 3D environment provided by the bioscaffolds was suitable for radiobiological research as well as being cost-effective. This model provides the opportunity to explore the biological consequences of different radiation modalities over prolonged periods of time. Introduction: Decellularized extracellular matrix (ECM) bioscaffolds have emerged as a promising three-dimensional (3D) model, but so far there are no data concerning their use in radiobiological studies. Material and Methods: We seeded two well-known radioresistant cell lines (HMV-II and PANC-1) in decellularized porcine liver-derived scaffolds and irradiated them with both high- (Carbon Ions) and low- (Photons) Linear Energy Transfer (LET) radiation in order to test whether a natural 3D-bioscaffold might be a useful tool for radiobiological research and to achieve an evaluation that could be as near as possible to what happens in vivo. Results: Biological scaffolds provided a favorable 3D environment for cell proliferation and expansion. Cells did not show signs of dedifferentiation and retained their distinct phenotype coherently with their anatomopathological and clinical behaviors. The radiobiological response to high LET was higher for HMV-II and PANC-1 compared to the low LET. In particular, Carbon Ions reduced the melanogenesis in HMV-II and induced more cytopathic effects and the substantial cell deterioration of both cell lines compared to photons. Conclusions: In addition to offering a suitable 3D model for radiobiological research and an appropriate setting for preclinical oncological analysis, we can attest that bioscaffolds seemed cost-effective due to their ease of use, low maintenance requirements, and lack of complex technology [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of a porous three-layered Functionally Graded Scaffold (FGS) based on κ-carrageenan for wound management. • Design and preparation of three FGS layers by exploiting κ-carrageenan interactions with multifunctional agents, such as arginine and whey protein isolate. • Set-up of a single-step freeze-drying process for FGS preparation. • FGS layers are characterized by different pore size, water content capability and mechanical properties, mimicking the structure of native skin tissue. • In vitro studies (fibroblast cell line) demonstrated the excellent biocompatibility and the ability of FGS layers to act as a support for cell growth. • In vivo experiments (murine model) highlighted that FGS layers were effective in promoting wound healing. Nowadays, chronic wounds are the major cause of morbidity worldwide and the healthcare costs related to wound care are a billion-dollar issue; chronic wounds involve a non-healing process that makes necessary the application of advanced wound dressings to promote skin integrity recovery. Functionally Graded Scaffolds (FGSs) are currently driving interest as promising candidates in mimicking the skin tissue environment and, thus, in enhancing a faster and more effective wound healing process. Aim of the present work was to design and develop a porous FGS based on κ-carrageenan (κCG) for the management of chronic skin wounds; a freeze-drying process was optimized to obtain in a single-step a three-layered FGS characterized by a pore size gradient functional to mimic the structure of native skin tissue. In addition to κCG, arginine and whey protein isolate were used as multifunctional agents for FGS preparation; these substances can not only intervene in some stages of wound healing but are able to establish non-covalent interactions with κCG, which were responsible for the production of layers with different pore size, water content capability and mechanical properties. Cell migration, adhesion and proliferation within the FGS structure were evaluated in vitro on fibroblasts and FGS wound healing potential was also studied in vivo on a murine model. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermoplastic polyurethane highly porous scaffolds are characterized by tendon-like mechanical properties. • Caseinophosphopeptides and chondroitin sulfate are constantly released over time from the scaffolds. • Caseinophosphopeptides adsorption into the porous scaffolds combined with chondroitin sulfate promote cell adhesion and proliferation. • The scaffolds enriched with chondroitin sulfate and caseinophosphopeptides in vivo do not cause any inflammatory effect. Tendon disorders are common injuries, which can be greatly debilitating as they are often accompanied by great pain and inflammation. Moreover, several problems are also related to the laceration of the tendon-to-bone interface (TBI), a specific region subjected to great mechanical stresses. The techniques used nowadays for the treatment of tendon and TBI injuries often involve surgery. However, one critical aspect of this procedure involves the elevated risk of fail due to the tissues weakening and the postoperative alterations of the normal joint mechanics. Synthetic polymers, such as thermoplastic polyurethane, are of special interest in the tissue engineering field as they allow the production of scaffolds with tunable elastic and mechanical properties, that could guarantee an effective support during the new tissue formation. Based on these premises, the aim of this work was the design and the development of highly porous 3D scaffolds based on thermoplastic polyurethane, and doped with chondroitin sulfate and caseinophosphopeptides, able to mimic the structural, biomechanical, and biochemical functions of the TBI. The obtained scaffolds were characterized by a homogeneous microporous structure, and by a porosity optimal for cell nutrition and migration. They were also characterized by remarkable mechanical properties, reaching values comparable to the ones of the native tendons. The scaffolds promoted the tenocyte adhesion and proliferation when caseinophosphopetides and chondroitin sulfate are present in the 3D structure. In particular, caseinophosphopeptides' optimal concentration for cell proliferation resulted 2.4 mg/mL. Finally, the systems evaluation in vivo demonstrated the scaffolds' safety, since they did not cause any inflammatory effect nor foreign body response, representing interesting platforms for the regeneration of injured TBI. [ABSTRACT FROM AUTHOR]

• Electrospun chitosan/glycosaminoglycan scaffolds for skin reparation were developed. • The scaffolds were insoluble in aqueous fluids after crosslinking by heating. • Chondroitin sulfate renders the scaffold best suited to heal lesions in murine model. • Chondroitin sulfate provides system flexibility for optimal preclinical performance. Burns and chronic wounds, often related to chronic diseases (as diabetes and cancer), are challenging lesions, difficult to heal. The prompt and full reconstitution of a functional skin is at the basis of the development of biopolymer-based scaffolds, representing a 3D substrate mimicking the dermal extracellular matrix. Aim of the work was to develop scaffolds intended for skin regeneration, according to: fabrication by electrospinning from aqueous polysaccharide solutions; prompt and easy treatment to obtain scaffolds insoluble in aqueous fluids; best performance in supporting wound healing. Three formulations were tested, based on chitosan (CH) and pullulan (P), associated with glycosaminoglycans (chondroitin sulfate - CS or hyaluronic acid – HA). A multidisciplinary approach has been used: chemico-physical characterization and preclinical evaluation allowed to obtain integrated information. This supports that CS gives distinctive properties and optimal features to the scaffold structure for promoting cell proliferation leading tissue reparation towards a complete skin restore. [ABSTRACT FROM AUTHOR]

Herein we developed a hydrogel based porous cross-linked scaffold intended for the treatment of chronic skin ulcers. It is made of collagen, the most abundant protein of mammals ECM, and chitosan, a natural polysaccharide endowed with numerous positive cues for wound repair. Different cross-linking methods, namely UV irradiation with the addition of glucose, addition of tannic acid as cross-linking agent and ultrasonication, were employed to prepare a cross-linked hydrogel with a highly interconnected 3D internal structure. The variables considered critical to obtain a suitable system for the envisaged application are the composition of hydrogels, especially the concentration of chitosan, and the concentration ratio between chitosan and collagen. Stable systems, characterized by high porosity, were obtained thanks to the use of freeze-drying process. To assess the influence of the above-mentioned variables on scaffold mechanical properties, a Design of Experiments (DoE) approach was exploited, which resulted in the identification of the best hydrogel composition. In vitro and in vivo assays on a fibroblast model cell line and on a murine model, respectively, demonstrated scaffold biocompatibility, biomimicry, and safety. [ABSTRACT FROM AUTHOR]

Herein we developed a hydrogel based porous cross-linked scaffold intended for the treatment of chronic skin ulcers. It is made of collagen, the most abundant protein of mammals ECM, and chitosan, a natural polysaccharide endowed with numerous positive cues for wound repair. Different cross-linking methods, namely UV irradiation with the addition of glucose, addition of tannic acid as cross-linking agent and ultrasonication, were employed to prepare a cross-linked hydrogel with a highly interconnected 3D internal structure. The variables considered critical to obtain a suitable system for the envisaged application are the composition of hydrogels, especially the concentration of chitosan, and the concentration ratio between chitosan and collagen. Stable systems, characterized by high porosity, were obtained thanks to the use of freeze-drying process. To assess the influence of the above-mentioned variables on scaffold mechanical properties, a Design of Experiments (DoE) approach was exploited, which resulted in the identification of the best hydrogel composition. In vitro and in vivo assays on a fibroblast model cell line and on a murine model, respectively, demonstrated scaffold biocompatibility, biomimicry, and safety. [ABSTRACT FROM AUTHOR]

[Display omitted] Periodontal regeneration is extremely limited and unpredictable due to structural complications, as it requires the simultaneous restoration of different tissues, including cementum, gingiva, bone, and periodontal ligament. In this work, spray-dried microparticles based on green materials (polysaccharides – gums - and a protein - silk fibroin) are proposed to be implanted in the periodontal pocket as 3D scaffolds during non-surgical treatments, to prevent the progression of periodontal disease and to promote the healing in mild periodontitis. Arabic or xanthan gum have been associated to silk fibroin, extracted from Bombyx mori cocoons, and loaded with lysozyme due to its antibacterial properties. The microparticles were prepared by spray-drying and cross-linked by water vapor annealing, inducing the amorphous to semi-crystalline transition of the protein component. The microparticles were characterized in terms of their chemico–physical features (SEM, size distribution, structural characterization – FTIR and SAXS, hydration and degradation properties) and preclinical properties (lysozyme release, antibacterial properties, mucoadhesion, in vitro cells adhesion and proliferation and in vivo safety on a murine incisional wound model). The encouraging preclinical results highlighted that these three-dimensional (3D) microparticles could provide a biocompatible platform able to prevent periodontitis progression and to promote the healing of soft tissues in mild periodontitis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polydioxanone in deep eutectic solvents has been spun via centrifugal spinning. • Polydioxanone microfibers as a rope or as a disk prove to possess suitable mechanical properties to be applied in skin tissue engineering. • Polydioxanone devices prove to be safe and effective to repair wound healing in an in vivo burn/excisional murine model. Fiber spinning technologies attracted a great interest since the beginning of the last century. Among these, electrospinning is a widely diffuse technique; however, it presents some drawbacks such as low fiber yield, high energy demand and the use of organic solvents. On the contrary, centrifugal spinning is a more sustainable method and allows to obtain fiber using centrifugal force and melted materials. The aim of the present work was the design and the development of polydioxanone (PDO) microfibers intended for tissue engineering, using centrifugal spinning. PDO, a bioresorbable polymer currently used for sutures, was selected as low melting polyester and DES (deep eutectic solvents), either choline chloride/citric acid (ChCl/CA) or betaine/citric acid (Bet/CA) 1:1 M ratio, were used to improve PDO spinnability. Physical mixtures of DES and PDO were prepared using different weight ratios. These were then poured into the spinneret and melted at 140 °C for 5 min. After the complete melting, the blends were spun for 1 min at 700 rpm. The fibers were characterized for physico chemical properties (morphology; dimensions; chemical structure; thermal behavior; mechanical properties). Moreover, the preclinical investigation was performed in vitro (biocompatibility, adhesion and proliferation of fibroblasts) and in vivo (murine burn/excisional model to assess safety and efficacy). The multidisciplinary approach allowed to obtain an extensive characterization to develop PDO based microfibers as medical device for implant to treat full thickness skin wounds. [ABSTRACT FROM AUTHOR]

The aim of the present work was the development of a powder formulation for the delivery of manuka honey (MH) bioactive components and platelet lysate (PL) in chronic skin ulcers. In particular pectin (PEC)/chitosan (CS) particles were prepared by ionotropic gelation in the presence of calcium chloride and subsequently characterized for particle size, hydration properties and mechanical resistance. Different experimental conditions (calcium chloride and CS concentrations; rest time in the cationic solution) were considered in order to obtain particles characterized by optimal size, hydration properties and mechanical resistance. Two different fractions of MH were examined: one (Fr1), rich in methylglyoxal and the other (Fr2), rich in polyphenols. Particles were loaded with Fr1, fraction able to enhance in vitro proliferation of human fibroblasts, and with PL. The presence of CS in Fr1-loaded particles produced an improvement in cell proliferation. Moreover, PL loading into particles did not affect the biological activity of the hemoderivative. In vivo efficacy of PL- and Fr1-loaded particles was evaluated on a rat wound model. Both treatments markedly increased wound healing to the same extent. [ABSTRACT FROM AUTHOR]

Hemoderivative tear substitutes contain various ephiteliotrophic factors, such as growth factors (GF), involved in ocular surface homeostasis without immunogenic properties. The aim of the present work was the loading of platelet lysate into contact lenses to improve the precorneal permanence of platelet lysate growth factors on the ocular surface to enhance the treatment of corneal lesions. To this purpose, chondroitin sulfate, a sulfated glycosaminoglycan, which is normally present in the extracellular matrix, was associated with platelet lysate. In fact, chondroitin sulfate is capable of electrostatic interaction with positively charged growth factors, in particular, with bFGF, IGF, VEGF, PDGF and TGF-β, resulting in their stabilization and reduced degradation in solution. In the present work, various types of commercially available contact lenses have been loaded with chondroitin sulfate or chondroitin sulfate in association with platelet lysate to achieve a release of growth factors directly onto the corneal surface lesions. One type of contact lenses (PureVision ® ) showed in vitro good proliferation properties towards corneal cells and were able to enhance cut closure in cornea constructs. [ABSTRACT FROM AUTHOR]

Because engineered tissues are designed for clinical applications in humans, a major problem is the contamination of cocultures and tissues by allogenic molecules used to grow stem cells in vitro. The protocols that are commonly applied to generate epidermal equivalents in vitrorequire the use of irradiated murine fibroblasts as a feeder layer for keratinocytes. In this study, we report a simple procedure for growing human keratinocytes, isolated from adult skin, to generate an epidermal construct on a collagen layer alone. In this model, no human or murine feeder layers were used to amplify cell growth, and isolated keratinocytes were seeded directly at high cell density on the collagen-coated flasks or coverslips in an epithelial growth medium containing low calcium concentration.Morphological, immunochemical, and cytokinetic features of epithelial colonies grown on the collagen layer were typical of keratinocytes and were comparable with those reported for keratinocytes grown on a feeder layer. The stratification of keratinocytes generated 3-dimensional synthetic constructs displaying a tissue architecture comparable with that of natural epidermis. Epithelial cells expressed specific markers of keratinocyte terminal differentiation, including involucrin and filaggrin. Nevertheless, the number of cell layers was lower than in natural skin, and electron microscopical analysis revealed that the overall organization of these layers was poor compared with natural epidermis, including the formation of junctional complexes, basement membrane, and keratinization. The lack of epithelial–mesenchymal interactions that occur during skin histogenesis may account for such an incomplete maturation of epidermal constructs. [ABSTRACT FROM AUTHOR]

Several bone grafting materials have been used in sinus augmentation procedures. Bio-Oss (deproteinized and sterilized bovine bone) has shown to have osteoconductive properties and no inflammatory or adverse responses have been published. In spite of these successful results, histologic data regarding bone augmentation using Bio-Oss in humans is scarce. The purpose of this study was to analyse the amount of Bio-Oss ossification in a case of maxillary sinus augmentation, recording and comparing histomorphometric data 8 months, 2 and 10 years after surgery. This long-term histologic evaluation of retrieved specimens has been performed, comparing histomorfometric measures at different times. Eight months after surgery we observed in 20 different thin sections of the specimen a mean amount of bone tissue (including medullar spaces) of 29.8% (and 70.2% of Bio-Oss) ± 2.6. At 2 years the bone tissue increased to 69.7% + 2.7 and 10 years after surgery it was 86.7% ± 2.8. The comparison of the means for each time has shown a highly significant increasing trend in bone formation associated with Bio-oss resorption: at 8 months, 2 and 10 years. [ABSTRACT FROM AUTHOR]