Tissue engineering provides in vitro biological substitutes, based on cells and three-dimensional matrices, which are able to overcome the clinical requirements of repair and regeneration, integrating themselves into the surrounded tissues and avoiding rejection phenomena. In this context, alginate and fibroin based biomaterials were developed to vehiculate the stromal vascular fraction (SVF), isolated from the adipose tissue. The use of this cellular population is considered as a promising approach for tissue regeneration, due to the trophic activities of SVF secretome, performed through paracrine mechanisms. In this thesis, two tissue engineering products (alginate beads and silk fibroin non-woven mat) loaded with adipose SVF were subcutaneously implanted in mice inbred C57BL/6 in order to promote the neoangiogenesis and the vascularization of the construct. Histological analysis showed that silk fibroin scaffold induce a typical foreign body reaction but, at the same time, promote the neo-vascularization of the implanted construct, helped by growth factors present in the SVF. Conversely, the alginate-based beads induce a more circumscribed chronic inflammatory reaction and promote the formation of vascular structures in situ. Therefore, it has been demonstrated that these scaffold are promising for the cell vehiculation in regenerative medicine field.
L’ingegneria tissutale prevede lo sviluppo in vitro di sostituti biologici, costituiti da cellule e matrici tridimensionali, che siano in grado sopperire alle necessità cliniche di riparazione e rigenerazione, integrandosi nel tessuto ospite ed evitando fenomeni di rigetto. In questo contesto sono stati sviluppati biomateriali a base di alginato (sistemi matriciali) e altri a base di fibroina (tessuto non tessuto) destinati alla veicolazione di frazione vascolare stromale (SVF) isolata dal tessuto adiposo. L’impiego di tale popolazione cellulare infatti si presenta come un valido approccio per la rigenerazione tissutale, mediata dall’azione trofica del secretoma attraverso meccanismi paracrini. In questo lavoro di tesi le due tipologie di prodotto (beads di alginato e TNT di fibroina) caricate di SVF sono stati impiantate nel sottocute di topi inbred C57BL/6 con l’obiettivo di promuovere la neoangiogenesi e la vascolarizzazione del costrutto. L'analisi istologica ha mostrato che lo scaffold di TNT di fibroina induce una reazione tipica da corpo estraneo ma, allo stesso tempo, promuove la neo-vascolarizzazione, nel sito d’impianto, favorita dai fattori di crescita presenti nella SVF. Al contrario, le beads di alginato creano una reazione infiammatoria cronica più circoscritta e induce la formazione di strutture vascolari in situ. Tali supporti si sono pertanto dimostrati promettenti per la veicolazione di cellule nel campo della medicina rigenerativa.
Risposta tissutale indotta dalla frazione vascolare stromale da tessuto adiposo veicolata in scaffold di alginato e fibroina in un modello murino.
BISSONE, ANNALISA
2014/2015
Abstract
Tissue engineering provides in vitro biological substitutes, based on cells and three-dimensional matrices, which are able to overcome the clinical requirements of repair and regeneration, integrating themselves into the surrounded tissues and avoiding rejection phenomena. In this context, alginate and fibroin based biomaterials were developed to vehiculate the stromal vascular fraction (SVF), isolated from the adipose tissue. The use of this cellular population is considered as a promising approach for tissue regeneration, due to the trophic activities of SVF secretome, performed through paracrine mechanisms. In this thesis, two tissue engineering products (alginate beads and silk fibroin non-woven mat) loaded with adipose SVF were subcutaneously implanted in mice inbred C57BL/6 in order to promote the neoangiogenesis and the vascularization of the construct. Histological analysis showed that silk fibroin scaffold induce a typical foreign body reaction but, at the same time, promote the neo-vascularization of the implanted construct, helped by growth factors present in the SVF. Conversely, the alginate-based beads induce a more circumscribed chronic inflammatory reaction and promote the formation of vascular structures in situ. Therefore, it has been demonstrated that these scaffold are promising for the cell vehiculation in regenerative medicine field.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/21393