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La cécité cornéenne touche 12,7 millions personnes globalement. Il y a une pénurie des cornées de donneurs humains (CDH), et donc les tissues disponibles sont implanté préférentiellement dans les patients avec des troubles cornéens à faible risque comme le kératocône et la dystrophie endothéliale de Fuchs. Les patients qui ont un risque élevé d’inflammation, comme ceux avec des brûlures acides, alcalines et thermiques, des infections et des ulcères, ne reçoivent pas de greffes pour leurs maladies cornéennes. Les biomatériaux offrent une alternative aux CDH en permettant le développement de solutions de régénération cornéenne avec une longue durée de conservation, une thermostabilité pour un déploiement en zone rurale, et biocompatibilité chez les patients à haut risque. Les biomatériaux peuvent être développés sous forme d’implants cornéens solides à greffer dans des opacités cornéennes ou sous forme de liquides gélifiants injectables qui peuvent sceller des petites perforations cornéennes. Les implants cornéens solides conviennent aux chirurgiens ophtalmologiques, mais les produits de comblement liquides peuvent être utilisés par les prestataires de médecine d’urgence ou le personnel médical non spécialisé dans les zones où les chirurgiens ophtalmologistes ne sont pas disponibles. Cette thèse explore les formulations de biomatériaux pour les cornéens solides et gélifiants in situ, leurs performances en tant que dispositifs composites, l’ajout de la stérilisation terminale à la fabrication d’implants cornéens solides et le développement de futures protéines mimétiques du collagène pour la formulation d’hydrogel. Le premier objectif de cette thèse était de développer un implant cornéen solide adapté à l’implantation chez les patients cornéens à haut risque. Les implants cornéens peptide-mimant-le-collagène-polyéthylène glycol-phosphorylcholine (PMC-PEG-MPC) et les implants recombinants de collagène humain de type III-phosphorylcholine (RCHIII-MPC) ont réussi à régénérer les cornées de mini-porcs et de lapins, respectivement. La phosphorylcholine présente dans la formulation PMC-PEG-MPC a diminué l’inflammation et fourni une alternative cornéenne viable dans les brûlures alcalines à haut risque. Des nanoparticules d’argent coiffées de peptides étaient fabriquées avec succès à la surface d’un implant cornéen solide de collagène porcin de type I. Ces implants ont inhibé P. aeruginosa, S. aureus et S. epidermidis in vitro et empêché la formation de biofilm à l’interface air-liquide. Ces implants cornéens solides élargissent la gamme d’efficacité pour inclure les personnes souffrant de brûlures alcalines et d’infections. Finalement, on a validé une méthode de stérilisation terminale des implants cornéens solides. Le RCHIII-MPC a été stérilisé en phase terminale avec succès à l’aide d’une irradiation par faisceau d’électrons, offrant une future voie pour la stérilisation terminale des implants cornéens solides à base de biomatériaux. Le deuxième objectif était de concevoir un hydrogel qui se solidifierait in situ pour sceller les perforations cornéennes. Le PMC-PEG était combiné avec du fibrinogène pour former “LiQD Cornea”, le premier produit de comblement cornéen liquide à être chimiquement réticulé avec succès in situ pour sceller les perforations cornéennes et les plaies chirurgicales chez le lapin et les mini-porcs. Pour le troisième objectif, ce projet fournit également une méthodologie future pour la production de protéines mimétiques de collagène personnalisées pour les futures formulations d’hydrogel. Dans l’ensemble, le collagène et les biomatériaux inspirés du collagène se sont révélés être des greffes et des scellants cornéens prometteurs avec des voies viables de fabrication commerciale., Corneal blindness and opacities affect 12.7 million people globally. There is a shortage of human donor corneas (HDCs), which are prioritized for patients with low risk corneal disorders like keratoconus and Fuch’s endothelial dystrophy. Patients with high-risk inflammatory conditions like acid, alklai and thermal burns, infections and ulcers are often unable to receive transplants to treat their corneal disorders. Biomaterials provide an alternative to HDCs by allowing the development of corneal regenerative solutions with a long-shelf life, thermostability for deployment in rural areas and biocompatibility in high-risk patients. Biomaterials can be developed as solid corneal implants to graft into large corneal opacities or as injectable in situ gelling liquids that can seal small corneal perforations. Solid corneal implants are suited for use by ophthalmic surgeons, but liquid fillers can be used by emergency medicine providers or non-specialized medical personnel in areas where ophthalmic surgeons are not available. This thesis explores biomaterials formulations for solid and in situ gelling corneal biomaterials, their performance as composite devices, the addition of terminal sterilization to the manufacture of solid corneal implants, and the development of future collagen mimetic proteins for hydrogel formulations. The first objective of this thesis was to develop a solid corneal implant suitable for implantation in high-risk corneal patients. Collagen-like-peptide-polyethylene glycolphosphorylcholine (CLP-PEG-MPC) corneal implants and recombinant human collagen type III-phosphorylcholine implants were successful in regenerating the corneas of mini-pigs and rabbits, respectively. The phosphorylcholine present in the CLP-PEG-MPC formulation decreased inflammation and provided a viable corneal alternative in high-risk alkali burns. Peptide-capped nanoparticles were successfully fabricated on the surface of a porcine and S. epidermidis in vitro and prevented biofilm formation at the air-liquid interface. These solid corneal implants expand the range of efficacy to include individuals with alkali burns and infections. This thesis validated a method of terminal sterilization for solid corneal implants. RHCIII-MPC was successfully terminally sterilized using electron-beam irradiation, providing a future avenue for terminal sterilization of biomaterials-based solid corneal implants. The second objective was to design a hydrogel that will solidify in situ to seal corneal perforations. CLP-PEG was combined with fibrinogen to form LiQD Cornea, the first liquid corneal filler to be successfully chemically crosslinked in situ to seal corneal perforations and surgical wounds in rabbit and mini-pigs. For the third objective, this project also provides future methodology for the production of custom collagen mimetic proteins for future hydrogel formulations. Overall, collagen and collagen-inspired biomaterials were demonstrated to be promising corneal grafts and sealants with viable pathways to commercial manufacture.

Mobility plays an important role in the cities by enabling people to carry out the most varied activities across the territory, as well as to ensure the city fully function. In addition, analogies to the human organism can be made by this urban dynamic, looking for solutions to specific issues. Moreover, this paper has been based by the premise that phenomena and urban elements could be conceptualized, explained and transformed from contemporary and innovative approaches applied in the medical field. For this reason, this paper aims to develop and present a new concept associated with urban mobility, based on the principles of regenerative medicine: the Regenerative Mobility, a concept with disruptive and evolutionary purposes. Furthermore, the structure of this paper is summarized by the introduction which contextualizes the theme, presents and characterizes the techniques used in the research. Additionally, the following chapters explore essential aspects of the city, explaining why it needs a mobility change and new concepts. Therefore, the concept of Regenerative Mobility is presented as a potential of mobility and cities improvement, followed by pragmatic cases, capable of illustrating some of its principles.

Chitosan scaffolds based on blending polymers are a common strategy used in tissue engineering. The objective of this study was evaluation the properties of scaffolds based on a ternary blend of chitosan (Chi), gelatin (Ge), and polyvinyl alcohol (PVA) (Chi/Ge/PVA), which were prepared by cycles of freeze-thawing and freeze-drying. It then was used for three-dimensional BRIN-BD11 beta-cells culturing. Weight ratios of Chi/Ge/PVA (1:1:1, 2:2:1, 2:3:1, and 3:2:1) were proposed and porosity, pore size, degradation, swelling rate, compressive strength, and cell viability analyzed. All ternary blend scaffolds structures are highly porous (with a porosity higher than 80%) and interconnected. The pore size distribution varied from 0.6 to 265 μm. Ternary blends scaffolds had controllable degradation rates compared to binary blend scaffolds, and an improved swelling capacity of the samples with increasing chitosan concentration was found. An increase in Young’s modulus and compressive strength was observed with increasing gelatin concentration. The highest compressive strength reached 101.6 Pa. The MTT assay showed that the ternary blends scaffolds P3 and P4 supported cell viability better than the binary blend scaffold. Therefore, these results illustrated that ternary blends scaffolds P3 and P4 could provide a better environment for BRIN-BD11 cell proliferation.

Globoid cell leukodystrophy (GLD) is an inherited lysosomal storage disease caused by β-galactocerebrosidase (GALC) deficiency. Gene therapy (GT) should provide rapid, extensive and lifetime GALC supply in central nervous system (CNS) tissues to prevent or halt irreversible neurologic progression. Here we used a lentiviral vector (LV) to transfer a functional GALC gene in the brain of Twitcher mice, a severe GLD model. A single injection of LV.GALC in the external capsule of Twitcher neonates resulted in robust transduction of neural cells with minimal and transient activation of inflammatory and immune response. Importantly, we documented a proficient transduction of proliferating and post-mitotic oligodendroglia, a relevant target cell type in GLD. GALC activity (30–50% of physiological levels) was restored in the whole CNS of treated mice as early as 8 days post-injection. The early and stable enzymatic supply ensured partial clearance of storage and reduction of psychosine levels, translating in amelioration of histopathology and enhanced lifespan. At 6 months post-injection in non-affected mice, LV genome persisted exclusively in the injected region, where transduced cells overexpressed GALC. Integration site analysis in transduced brain tissues showed no aberrant clonal expansion and preferential targeting of neural-specific genes. This study establishes neonatal LV-mediated intracerebral GT as a rapid, effective and safe therapeutic intervention to correct CNS pathology in GLD and provides a strong rationale for its application in this and similar leukodystrophies, alone or in combination with therapies targeting the somatic pathology, with the final aim of providing an effective and timely treatment of these global disorders.