This work was supported by The British Heart Foundation and The Oak Foundation.

Eseguire tutti gli esperimenti su animali secondo protocolli approvati dal Comitato istituzionale per l&#39;uso e la cura di animali da laboratorio. 1. Preparazione della cultura media <ol><li> Fai terreni di coltura per la linea cellulare di fibroblasti umani CCL-153: F-12K Medium, siero fetale bovino 10% (FBS) e 100 U / ml di penicillina e la streptomicina. </li><li> Fai riprogrammazione supporti per la generazione PiPSC: mezzo di Eagle modificato di Knockout Dulbecco (DMEM) contenente il 20% Knockout siero sostituzione, 0,1 mm β-mercaptoetanolo, 0.1 Minimum mM Essential Medium (MEM) non-aminoacidi essenziali, 10 ng / ml di base del fattore di crescita dei fibroblasti 2 (bFGF-2) e 100 U / ml di penicillina e streptomicina. Aggiungi bFGF-2 al momento ogni volta prima di usare i media. </li><li> Rendere Differenziazione media (DM) per indurre cellule muscolari lisce (SMC) differenziazione: α-MEM supporti contenente 10% FBS, 0,1 mM β-mercaptoetanolo, 100 U / ml penicillina e streptomicina e 25 ng / ml Platelet Derived Growth Factor(PDGF-ββ). </li><li> Fai endoteliale Differenziazione media (CE-DM) per indurre cellule endoteliali (EC) differenziazione: crescita endoteliale media-2 (EGM-2) supporto contenente 50 ng / ml Vascular Endothelial Growth Factor (VEGF) e 100 U / ml di penicillina e la streptomicina. </li></ol> 2. fibroblasti umani Riprogrammare in Parzialmente-cellule staminali pluripotenti indotte (PiPSC) <ol><li> Culture linea cellulare di fibroblasti umani CCL-153 0,04% su fiasche rivestite soluzione di gelatina in mezzo di coltura. </li><li> Cellule Passage ogni 3 giorni con un rapporto di 1: 6. Utilizzare le cellule prima del passaggio 9 per l&#39;efficienza ottimale di generazione PiPSC. Le cellule sono pronte per la trasfezione upon raggiunge l&#39;80 - 90% di confluenza. </li><li> Linearizza pCAG2LMKOSimO plasmide policistronica contenente 4 fattori di riprogrammazione ottamero vincolante fattore di trascrizione 4 (OCT4), SOX2, fattore Kruppel-like 4 (Klf4) e C-MYC (pCAG-OSKM). Digest 5 mg di plasmide con 5 unità di enzima di restrizione Pvul per 3 ore a 37 ° C. Purificareil plasmide con un kit commerciale secondo il protocollo del produttore. </li><li> Trasfettare 2 x 10 6 fibroblasti umani con 4 mg di linearizzato pCAG-OSKM plasmide di elettroporazione con kit di fibroblasti del derma umano (NHDF) nucleofection secondo il protocollo del produttore. Sementi delicatamente cellule trasfettate sul pre 0,04% di gelatina rivestito pallone T25 contenente 5 ml di pre-riscaldato Riprogrammazione media. </li><li> Dopo 24 ore, cambiare mezzo con supplementi di 25 mg / ml neomicina per selezionare una popolazione pura di cellule trasfettate. </li><li> Cambiare medio a giorni fino al giorno 4. Nota: fibroblasti umani diventano PiPSC dopo 4 giorni di riprogrammazione. </li></ol> 3. Differenziazione dei PiPSC in endoteliali e cellule muscolari lisce <ol><li> PiPSC Seed su piatti collagene IV pre-rivestite contenenti DM per 4 giorni di indurre la differenziazione in SMC. Cambiare medio a giorni fino al giorno 4. </li><li> PiPSC Seed sul collagene IV pre-rivestite piatti containing endoteliale-DM per 6 giorni per indurre il differenziamento in cellule endoteliali. Cambiare medio a giorni fino al giorno 6. </li></ol> 4. decellularized Aorta Graft Preparazione Nota: Tutte le soluzioni e le attrezzature devono essere sterili. <ol><li> Sacrifica il mouse per dislocazione cervicale e fissare il mouse in posizione supina al microscopio di dissezione. </li><li> Tagliare lo sterno e intorno alla gabbia toracica per aprire la cavità toracica. Rimuovere il cuore, i polmoni e dell&#39;esofago per esporre l&#39;aorta. Rimuovere delicatamente il grasso peri-aorta con una pinza. </li><li> Tagliare l&#39;aorta dalla estremità anteriore con le forbici e tenere delicatamente l&#39;estremità con una pinza smussato. Staccare l&#39;aorta dalla colonna spina dorsale dietro per via smussa. Chiudere accuratamente tutte le arterie si diramano dall&#39;aorta da legatura con elettrocoagulatore bipolare e il taglio dal fondo della legatura con le forbici. </li><li> Utilizzare una siringa da 5 ml per irrigare il lume aorta con 3 ml di soluzione salina contenente 100 U di eparina per prevenire la formazione di coaguli di sangue. </li><li> Tagliare l&#39;estremità posteriore della aorta prima si dirama nel renale. Mantenendo l&#39;integrità della aorta è molto importante durante l&#39;intera procedura. </li><li> Lavare lume aorta con 5 ml di soluzione 0,075% sodio dodecil solfato (SDS) diluita in tampone fosfato (PBS). </li><li> Mettere a bagno l&#39;aorta toracica in 0,075% soluzione SDS in una capsula di Petri 10 cm. Porre la capsula Petri in un agitatore orbitale per 2 ore a 150 rpm a RT. </li><li> Lavare lume aorta con 5 ml di PBS. </li><li> Immergere l&#39;aorta in PBS in una capsula di Petri 10 cm. Porre la capsula Petri sul agitatore orbitale per 2 ore a 150 giri al minuto a temperatura ambiente. Aggiorna PBS ogni 20 min. </li><li> Lavare lume aorta con 5 ml di PBS. </li><li> Tenere decellularized trapianto dell&#39;aorta in PBS a 4 ° C per un massimo di una settimana. </li></ol> 5. Doppio Semina di PiPSC e bioreattore condizionata Nota: Tutti soluziones ed apparecchiature devono essere sterili. Eseguire tutte le operazioni in una cappa di coltura di tessuti. <ol><li> Assemblare il circuito di flusso bioreattore come illustrato in figura 1. Collegare camera di incubazione, serbatoio media, pompa peristaltica e la camera rispetto tubazione. Il volume minimo di supporto necessari per la circolazione è di 40 ml. </li><li> Pre-condizione di nave decellularized con terreno di coltura immergendo l&#39;aorta in mezzo DM in una capsula di Petri 10 cm. Porre la capsula Petri l&#39;agitatore orbitale per 1 ora a 50 rpm a RT. </li><li> Inserire uno centimetri tubi lunghezza Nylon (OD 0,9 millimetri, ID 0,75 millimetri) in entrambe le estremità della nave decellularized al microscopio. Legare la nave e le provette con 8-0 punti di sutura in seta. </li><li> Montare l&#39;innesto aorta decellularized nella camera di incubazione collegando i tubi di nylon con le porte di ingresso e di uscita (1/32 &quot;tubi) dalla parete della camera. Mantenere camera di incubazione con 5mls di media ogni volta. </li><li> Trypsinize PiPSC aggiungendo pre-riscaldatotripsina per coprire il piatto cultura e oscillare delicatamente il piatto 10 volte. Eliminare la tripsina e lasciare il piatto in incubatrice per 2 - 3 min. Aggiungere mezzo di coltura pre-riscaldato nel piatto e miscelare il mezzo con le cellule. </li><li> Contare il numero di cellule utilizzando un emocitometro. Centrifugare due aliquote di sospensioni cellulari contenenti 5 x 10 5 cellule ciascuno per 5 min a 300 x g. Aspirare completamente il surnatante. </li><li> Dopo aspirando completamente il surnatante, risospendere 1 pellet delle PIP pellet cellulari in 50 ml di DM. Iniettare la sospensione cellulare nel lume del vaso decellularized. </li><li> Poi, risospendere il pellet altro Pips cellulare in 100 ml di Matrigel. Pipetta con cura il composto sulla aorta trapianto decellularized. </li><li> Attendere 10 - 15 minuti fino a quando la miscela si trasforma in uno stato simile a gel e uniformemente avvolge intorno alla superficie esterna del serbatoio. Riempire la camera di incubazione con DM. </li><li> Mettere il tutto in una impostazione di CO 2 incubatore 5% bioreattore a 37 ° C. Ruotare manualmente l&#39;innesto decellularized 90 ° intorno all&#39;asse longitudinale ogni mezz&#39;ora nel primo 2 hr. </li><li> Tenere cultura statica per 12 ore per permettere l&#39;adesione cellulare. </li><li> Invia DM attraverso il lume dalla pompa peristaltica di indurre il differenziamento delle cellule muscolari lisce. Inizia portata iniziale a 5 ml / min e aumento graduale a 20 ml / min oltre 24 ore. </li><li> Mantenere il flusso medio circolante a 20 ml / min per 24 ore. </li><li> Arrestare il flusso medio e spostare la definisce dell&#39;incubatore bioreattore. </li><li> Re-seme lume dell&#39;innesto con PiPSC. Trypsinize, contare e centrifugare 1 x 10 6 PiPSC come in passaggi 5,5-5,6. Risospendere le cellule in 50 ml di EGM-2 di media contenenti 50 ng / ml VEGF. Iniettare la miscela di cellule nel lume del trapianto. </li><li> Cambiare la media nella camera di incubazione e tutta la circolazione a EGM-2 terreno contenente 50 ng VEGF / ml di indurre il differenziamento endoteliale. </li><li> Spostare l&#39;impostazione torna th bioreattoree incubatore. Ruotare manualmente l&#39;innesto di 90 ° ogni 30 min nelle prime 2 ore e poi mantenere una cultura statica per 12 ore. </li><li> Inizia circolante flusso da 5 ml / min e aumento graduale a 35 ml / min. Mantenere la portata a 35 ml / min per 5 giorni. Cambia circolante e media camera ogni altro giorno. </li><li> Raccolto l&#39;innesto progettato per un&#39;ulteriore innesto di mouse. </li></ol> 6. Accrescimento di doppia testa di serie PiPSC Graft in Mice <ol><li> Utilizzare NOD.CB17-Prkdc SCID / NcrCrl topi maschi come destinatari nave innesto. Assicurarsi sempre che i topi sono circa 10 settimane di vita, pesano circa 25 - 35 g, e sono in buone condizioni di salute. </li><li> Anestetizzare topo ricevente somministrando una combinazione di Hypnorm (25 mg / kg) e Hypnovel (25 mg / kg) per via intraperitoneale. Applicare vaselina pomata oftalmica sugli occhi per prevenire la secchezza mentre sotto anestesia. Confermare anestesia efficiente assicurando che i topi hanno muscoli rilassati e respirano costantemente. <ol><li> Fissare il mouse in posizione supina con il collo rasato ed esteso. Somministrare atropina solfato (1,7 mg / kg) in combinazione con gli anestetici per assicurare che il tratto respiratorio mouse rimane chiaro. </li></ol></li><li> Preparare una incisione mediana della mandibola sterno del mouse. Sotto un microscopio da dissezione con 5- a 10 volte di amplificazione, sollevare le ghiandole salivari giuste lateralmente e rimuovere il muscolo cleidomastoid diritto di esporre la carotide comune destra. </li><li> Rimuovere delicatamente tessuti allegate mobilitare destra carotide comune dall&#39;estremità distale verso l&#39;estremità prossimale. Legare la porzione centrale della carotide comune due volte con una sutura di seta 8-0 e sezionare tra i due legami. </li><li> Passare attraverso un bracciale in tubo di nylon autoclavabile in ogni estremità nave e fissare ogni estremità con fascette microhemostat. </li><li> Rimuovere sutura cravatta su un&#39;estremità e applicare una goccia di eparina (100 U / ml). Subito dopo, invertire l&#39;estremità distale della the dell&#39;arteria per coprire l&#39;intero corpo bracciale e fissare il vaso invertita con una sutura di seta 8-0 al bracciale. <ol><li> Ripetere la stessa procedura per l&#39;altra porzione dell&#39;arteria. Arteria Lavare con soluzione fisiologica per rimuovere coaguli di sangue. </li></ol></li><li> Impiantare un innesto nave decellularized tra due estremità della carotide facendo scorrere le estremità dei vasi decellularized degli oltre polsini arteria e fissandolo con suture di seta 8-0. Rimuovere pinze vascolari da entrambi termina prima di valutare la pulsazione dell&#39;innesto. </li><li> Posizionare la ghiandola salivare destra nella sua posizione originaria. Chiudere la pelle sul luogo chirurgica con sutura interrotta con una sutura 6-0 polyglactin. </li><li> Coerentemente osservare i segni vitali del mouse dopo la procedura è completata, fino a quando non riprende coscienza. Sacrificio topi riceventi da cervicali dislocazione e dei vasi di raccolta innesti o 24 ore o 3 settimane più tardi per ulteriori analisi. </li></ol>

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Il protocollo attuale indica un suono, veloce strategia, semplice, efficiente e riproducibile in cui i vasi ingegneria tessutale funzionali possono essere generati utilizzando PiPSC da fibroblasti umani. Questa tecnica rappresenta uno strumento prezioso per la medicina rigenerativa, l&#39;ingegneria dei tessuti e terapia cellulare potenzialmente paziente-specifica in un prossimo futuro. Passaggi critici per assicurare l&#39;efficacia del protocollo comprendono la preparazione di PiPSC, preparazione di innesti aortica st...

La costruzione di condotti vascolari è una strategia fondamentale per la riparazione chirurgica di vasi danneggiati e feriti derivanti da malattie cardiovascolari. Ad oggi, materiali protesici utilizzati in chirurgia includono polimeri sintetici biocompatibili (politetrafluoroetilene [Teflon], politetrafluoroetilene espanso [ePTFE, Gore-Tex] o polietilene tereftalato [Dacron]), trapianti, tessuto autologo (pericardio o vena safena) e xenotrapianti 1. Mentre innesti artificiali (ad esempio, Gore-Tex e Dacron) sono più comunemente utilizzati, questi materiali possono causare numerose complicazioni a breve e lungo termine, che includono la stenosi, deposizione di calcio, trombo-embolizzazione e infezioni. Anche se i pazienti con innesti biologici presentano diminuite eventi tromboembolici, che ancora incontrano limitazioni come ad esempio il fallimento del trapianto secondario e durata accorciata a causa di calcificazione degrado 2. Pertanto, nonostante i significativi miglioramenti in t chirurgicaechniques corso degli anni, ricercatori e clinici sono ancora gravati con la necessità di individuare il condotto ideale per le malattie vascolari. Più recentemente, il campo di ricerca di ingegneria del tessuto vascolare ha generato un concetto in cui le cellule sono incorporati in scaffold biodegradabili, con lo scopo di creare un ambiente biomimetico che esemplifica una nave funzionale per successo innesto 1. Fondamentalmente, il successo dei costrutti vascolari dipendono tre componenti essenziali; cellule che compongono il ponteggio, cioè, uno strato interno di cellule endoteliali e di uno strato di cellule muscolari lisce, un&#39;impalcatura contenente la matrice extracellulare appropriata per fornire proprietà meccaniche paragonabili alla vascolarizzazione nativa, e la segnalazione molecolare / cellulare che è richiesto per avviare / regolazione riparazione. Lungo pervietà dell&#39;innesto termine e lo sviluppo sostenibile dei neo-tessuti sono altamente dipendenti semina cellulare efficace di ponteggi, thereby rendendo la decisione di tipo di cellula di importanza critica. Diverse relazioni dimostrano l&#39;uso di cellule endoteliali mature e cellule muscolari lisce da varie fonti di sviluppare condotte di piccolo diametro 3-6. Sebbene promettenti, la mancanza di vasi autologhi sufficienti per ottenere endoteliali mature e cellule muscolari lisce rimangono un onere considerevole. Più di recente, le cellule staminali provenienti da diverse fonti sono state sfruttate per applicazioni di ingegneria dei tessuti vascolari. Cellule mononucleate Infatti, una varietà di tipi di cellule staminali comprese le cellule staminali embrionali 7, indotto cellule staminali pluripotenti (iPSCs) 8,9, PiPSC 10,11, derivate dal midollo osseo 12, cellule staminali mesenchimali 13, cellule progenitrici endoteliali della parete vasale e adulti -derived cellule staminali antigene-1 (Sca-1) + cellule staminali / progenitrici 14,15 sono stati tutti dimostrato di essere in grado di differenziarsi in cellule endoteliali sia funzionale o muscolari lisce in risposta ai media definiti econdizioni di coltura. Inoltre, la capacità di auto rinnovamento illimitata delle cellule staminali le rendono migliori candidati a differenza endoteliali mature e cellule della muscolatura liscia che può dividere solo per un numero finito di volte prima di subire l&#39;arresto della crescita e senescenza. La selezione del materiale per generare scaffold tessuto successo nave progettata per l&#39;innesto dipende da diversi fattori quali la biocompatibilità, le proprietà biomeccaniche, e il tasso di biodegradazione. Fondamentalmente, i materiali usati per creare scaffold per gli innesti devono essere biodegradabili e non verranno montati destinatario inutili risposte immunitarie. Inoltre, esso deve comprendere una porosità e microstruttura adatto per il fissaggio e la sopravvivenza cellulare successiva. Ad oggi, i materiali più comuni utilizzati per ponteggi in ingegneria dei tessuti vascolari comprendono polimeri dell&#39;acido poliglicolico, acido polilattico, e poli ε-caprolattone 16. Più recentemente, materiali biologici decellularized hannoanche state applicate con successo. Diversi laboratori hanno dimostrato che la semina umana decellularized, cane o vasi suina con cellule autologhe fornito un innesto biologico che ha resistito coagulazione e iperplasia intimale 17-19. Altre strategie di ingegneria del tessuto vascolare includono innesti vascolari extracellulari a base di proteine ​​della matrice ad esempio, cellule semina in fibrina gel 13 e generando fogli cellulari senza supporto impalcatura 20, 21. L&#39;attuale protocollo dimostra la differenziazione di PiPSC umana in endoteliale funzionale e cellule muscolari lisce, la generazione di un bioreattore costituito da un ponteggio nave decellularized per porto cellule vascolari PiPSC-derivati ​​funzionali, e l&#39;innesto dei vasi ingegneria tessutale in grave immunodeficienza combinata (SCID ) topi. PiPSC sono un tipo di cellule ottimale da utilizzare per l&#39;ingegneria dei tessuti di innesti per vasi, perché queste cellule non formano tumori in topi o sollevano eticorisposte allo-immunitarie. Inoltre, abbiamo dimostrato che la strategia per la generazione di cellule muscolari Pip-cellule endoteliali e semi-liscio è efficiente e riproducibile 10,11. Successivamente, abbiamo progettato una nave decellularized per la semina delle cellule vascolari PiPSC derivate per imitare da vicino le proteine ​​della matrice che esiste all&#39;interno di un vaso nativo, aumentando così l&#39;innesto e la sopravvivenza di efficacia. Inoltre, la decellularization dei vasi prima PiPSC semina impedisce il verificarsi di risposte infiammatorie montati da tipi di cellule immunitarie quali macrofagi. Ancora più importante, questo protocollo non rappresenta solo un metodo per generare promettenti condotti vascolari per la traduzione in esseri umani, ma fornisce anche strumenti preziosi di studio e la comprensione dei meccanismi molecolari che regolano la rigenerazione del tessuto vascolare attraverso modelli di mouse.

<table border="0" cellpadding="0" cellspacing="0" >
	<tbody>
		<tr >
			<td >Human Fibroblasts CCL-153</td>
			<td >ATCC</td>
			<td >CCL-153</td>
			<td>Prenatal human embryonic fibroblasts</td>
		</tr>
		<tr >
			<td >ATCC F-12K Medium (Kaighn&#39;s Modification of Ham&#39;s F-12 Medium)</td>
			<td >ATCC</td>
			<td >30-2004</td>
			<td></td>
		</tr>
		<tr >
			<td >Fetal Bovine Serum</td>
			<td >ATCC</td>
			<td >30-2020</td>
			<td></td>
		</tr>
		<tr >
			<td >Knockout DMEM medium optimized for embryonic stem cells</td>
			<td >Life technologies (Gibco)</td>
			<td >12660-012</td>
			<td></td>
		</tr>
		<tr >
			<td >Knockout Serum Replacement</td>
			<td >Life technologies (Invitrogen)</td>
			<td >10828-028</td>
			<td></td>
		</tr>
		<tr >
			<td >Human Basic FGF-2&#160;</td>
			<td >Miltenyi Biotech</td>
			<td >130-093-837</td>
			<td></td>
		</tr>
		<tr >
			<td >alpha-MEM medium</td>
			<td >Life technologies (Invitrogen)</td>
			<td >32571093</td>
			<td></td>
		</tr>
		<tr >
			<td >Human PDGF</td>
			<td >R&#38;D System</td>
			<td >120-HD-001</td>
			<td></td>
		</tr>
		<tr >
			<td >Gelatin Solution 2%</td>
			<td >Sigma</td>
			<td >G1393</td>
			<td></td>
		</tr>
		<tr >
			<td >Plasmid 20866: pCAG2LMKOSimO (SOX2, OCT4, KLF4, C-MYC)</td>
			<td >Addgene</td>
			<td >20866</td>
			<td></td>
		</tr>
		<tr >
			<td >&#160;PvuI Restriction Enzyme</td>
			<td >New England Biolabs</td>
			<td >RO150S</td>
			<td></td>
		</tr>
		<tr >
			<td >SureClean Plus</td>
			<td >Bioline</td>
			<td >BIO-37047</td>
			<td></td>
		</tr>
		<tr >
			<td >Nucelofection Kit (NHDF Kit)</td>
			<td >LONZA</td>
			<td >VPD-1001</td>
			<td></td>
		</tr>
		<tr >
			<td >Neomycin</td>
			<td >SIGMA</td>
			<td >G418</td>
			<td>Selection of&#160;</td>
		</tr>
		<tr >
			<td >KL 1500 LCD, Illumination for Stereo Microscopy</td>
			<td >SCHOTT</td>
			<td >KL 1500 LCD</td>
			<td>Cold light illumination for stereo microscopy</td>
		</tr>
		<tr >
			<td >Nikon Zoom Steromicroscope SMZ800</td>
			<td >Nikon</td>
			<td >SMZ800</td>
			<td></td>
		</tr>
		<tr >
			<td >Heparin sodium salt</td>
			<td >Sigma</td>
			<td >H3393</td>
			<td></td>
		</tr>
		<tr >
			<td >10% SDS Stock Solution Molecular Biology Reagent</td>
			<td >Severn Biotech</td>
			<td >CAS 151-21-3</td>
			<td></td>
		</tr>
		<tr >
			<td >Dulbecco&#39;s Phosphate Buffered Saline</td>
			<td >Sigma</td>
			<td >D8537</td>
			<td></td>
		</tr>
		<tr >
			<td >Matrigel (10mg/ml)</td>
			<td >BD</td>
			<td >A6661</td>
			<td></td>
		</tr>
		<tr >
			<td >Shaker IKA Vibrax with Shaking platform VX 7&#160;</td>
			<td >Jepson Bolton&#39;s, Janke&#38;Kunkel</td>
			<td >S32-102</td>
			<td></td>
		</tr>
		<tr >
			<td >Masterflex L/S Digital Pump Drive</td>
			<td >Cole-Parmer</td>
			<td >WZ-07523-80</td>
			<td></td>
		</tr>
		<tr >
			<td >Masterflex L/S 6-channel, 6-roller cartridge pump head</td>
			<td >Cole-Parmer</td>
			<td >EW-07519-15</td>
			<td></td>
		</tr>
		<tr >
			<td >Masterflex L/S large cartridges for pump head</td>
			<td >Cole-Parmer</td>
			<td >EW-07519-75</td>
			<td></td>
		</tr>
		<tr >
			<td >Masterflex platinum-cured silicone pump tubing, L/S 14, 25 ft</td>
			<td >Cole-Parmer&#160;</td>
			<td >WZ-96410-14</td>
			<td >Tubing goes through the peristaltic pump</td>
		</tr>
		<tr >
			<td >0.5mm ID, 0.8 mm OD Silicone Tubing</td>
			<td >SILEX</td>
			<td >N/A</td>
			<td>Tubings connect incubation chamber, media reservoir and compliance chamber&#160;</td>
		</tr>
		<tr >
			<td >Fitting Reducer 0.5 to 1.6, natural Polypropyline</td>
			<td >Ibidi</td>
			<td >10829</td>
			<td>Adapter connect above two types of tubings</td>
		</tr>
		<tr >
			<td >1/32&#34; Tubing, ID 0.01&#34; (250&#181;m) Material: PEEK</td>
			<td >LabSmith</td>
			<td >T-132-010P</td>
			<td>Tubing through the incubation chamber wall which connects the graft with outside tubing</td>
		</tr>
		<tr >
			<td >One-Piece Fittings&#160;</td>
			<td >LabSmith</td>
			<td >T-132-100</td>
			<td>Fix the above tubings through the incubation chamber wall</td>
		</tr>
		<tr >
			<td >Nylon tubes (OD 0.9mm, ID 0.75mm)&#160;</td>
			<td >Smiths Medical</td>
			<td >N/A</td>
			<td>Tubings insert into two ends of the aorta graft</td>
		</tr>
		<tr >
			<td >NOD.CB17-Prkdcscid/NcrCrl mouse</td>
			<td >Charles River</td>
			<td ></td>
			<td ></td>
		</tr>
		<tr >
			<td >Surgical sutures, 8-0&#160; silk</td>
			<td >ETHICON</td>
			<td >W819</td>
			<td ></td>
		</tr>
		<tr >
			<td >Hypnorm</td>
			<td >Vetapharm</td>
			<td >Vm21757/4000</td>
			<td >Neuroleptanalgesic for use in mice</td>
		</tr>
		<tr >
			<td >Hypnovel (Midazolam)</td>
			<td >Roche</td>
			<td >59467-70-8</td>
			<td >Induction of anaesthesia</td>
		</tr>
		<tr >
			<td >Dissecting microscope</td>
			<td >Carl Zeiss</td>
			<td >Stemi 2000</td>
			<td ></td>
		</tr>
		<tr >
			<td >Nylon Tubing</td>
			<td >Portex LTD</td>
			<td >800/200/100/200</td>
			<td >0.65 mm in diameter and 1 mm in length; to make artery cuff</td>
		</tr>
		<tr >
			<td >Electrocoagulator</td>
			<td >Martin&#160;</td>
			<td >SN 54.131</td>
			<td >Ligation of artery branches on aorta</td>
		</tr>
		<tr >
			<td >Bipolar micro hemostat forceps</td>
			<td >Martin</td>
			<td >80-91-12-04</td>
			<td >Fixation of vessel ends</td>
		</tr>
		<tr >
			<td >Vessel Dilator</td>
			<td >S&#38;T</td>
			<td >JFX-7</td>
			<td ></td>
		</tr>
		<tr >
			<td >Vessel Dilator</td>
			<td >S&#38;T</td>
			<td >JFL-3dZ</td>
			<td ></td>
		</tr>
		<tr >
			<td >Vessel Dilator</td>
			<td >S&#38;T</td>
			<td >D-5aZ</td>
			<td ></td>
		</tr>
		<tr >
			<td >Mini applier&#160;</td>
			<td >AESCULAP</td>
			<td >FE572K</td>
			<td ></td>
		</tr>
		<tr >
			<td >Micro hemostats clips</td>
			<td >AESCULAP</td>
			<td >FE720K</td>
			<td ></td>
		</tr>
		<tr >
			<td >Surgical sutures, 6-0 VICRYL</td>
			<td >ETHICON</td>
			<td >V489</td>
			<td ></td>
		</tr>
	</tbody>
</table>

generation and grafting of tissue-engineered vessels in a mouse model

The construction of vascular conduits is a fundamental strategy for surgical repair of damaged and injured vessels resulting from cardiovascular diseases. The current protocol presents an efficient and reproducible strategy in which functional tissue engineered vessel grafts can be generated using partially induced pluripotent stem cell (PiPSC) from human fibroblasts. We designed a decellularized vessel scaffold bioreactor, which closely mimics the matrix protein structure and blood flow that exists within a native vessel, for seeding of PiPSC-endothelial cells or smooth muscle cells prior to grafting into mice. This approach was demonstrated to be advantageous because immune-deficient mice engrafted with the PiPSC-derived grafts presented with markedly increased survival rate 3 weeks after surgery. This protocol represents a valuable tool for regenerative medicine, tissue engineering and potentially patient-specific cell-therapy in the near future.

La generazione di successo di PiPSC stata confermata 4 giorni dopo nucleofecting fibroblasti umani con un plasmide pCAG2LMKOSimO linearizzato portando 4 fattori di trascrizione, Oct4, Sox2 Klf4 e c-Myc (OSKM). PiPSC visualizzato un fenotipo nettamente distinti rispetto ai fibroblasti (Figura 2A) ed espressa 4 fattori di riprogrammazione a mRNA (Figura 2B) e di proteine ​​(Figura 2C) 10 livelli. L&#39;efficacia di un innesto vascolare basato PiPSC è forte...

Watch this Scientific Journal Video about Generation and Grafting of Tissue-engineered Vessels in a Mouse Model at JoVE.com

Generation and Grafting of Tissue-engineered Vessels in a Mouse Model

Qui, vi presentiamo un protocollo per generare ingegneria dei tessuti dei vasi innesti che sono funzionali per l&#39;innesto in topi con un doppio semina cellule staminali pluripotenti indotte in parte (PiPSC) - derivato cellule muscolari lisce e PiPSC - cellule endoteliali derivate su una nave decellularized ponteggio bioreattore.

Generazione e innesto delle navi tissutale in un modello di topo

The construction of vascular conduits is a fundamental strategy for surgical repair of damaged and injured vessels resulting from cardiovascular diseases. ...

generation-and-grafting-of-tissue-engineered-vessels-in-a-mouse-model

Research

JoVE Journal

Bioengineering

11.9K Views.  King's College London BHF Centre.  Qui, vi presentiamo un protocollo per generare ingegneria dei tessuti dei vasi innesti che sono funzionali per l'innesto in topi con un doppio semina cellule staminali pluripotenti indotte in parte (PiPSC) - derivato cellule muscolari lisce e PiPSC - cellule endoteliali derivate su una nave decellularized ponteggio bioreattore. 

Video: Generation and Grafting of Tissue-engineered Vessels in a Mouse Model

Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves

Limitations of currently available prosthetic valves, xenografts, and homografts have prompted a recent resurgence of developments in the area of tri-leaflet polymer valve prostheses. However, identification of a protocol for initial assessment of polymer valve hydrodynamic functionality is paramount during the early stages of the design process. Traditional in vitro pulse duplicator systems are not configured to accommodate flexible tri-leaflet materials; in addition, assessment of polymer valve functionality needs to be made in a relative context to native and prosthetic heart valves under identical test conditions so that variability in measurements from different instruments can be avoided. Accordingly, we conducted hydrodynamic assessment of i) native (n = 4, mean diameter, D = 20 mm), ii) bi-leaflet mechanical (n= 2, D = 23 mm) and iii) polymer valves (n = 5, D = 22 mm) via the use of a commercially available pulse duplicator system (ViVitro Labs Inc, Victoria, BC) that was modified to accommodate tri-leaflet valve geometries. Tri-leaflet silicone valves developed at the University of Florida comprised the polymer valve group. A mixture in the ratio of 35:65 glycerin to water was used to mimic blood physical properties. Instantaneous flow rate was measured at the interface of the left ventricle and aortic units while pressure was recorded at the ventricular and aortic positions. Bi-leaflet and native valve data from the literature was used to validate flow and pressure readings. The following hydrodynamic metrics were reported: forward flow pressure drop, aortic root mean square forward flow rate, aortic closing, leakage&#160;and regurgitant volume, transaortic closing, leakage, and total energy losses. Representative results indicated that hydrodynamic metrics from the three valve groups could be successfully obtained by incorporating a custom-built assembly into a commercially available pulse duplicator system and subsequently, objectively compared to provide insights on functional aspects of polymer valve design.

There has been renewed interest in developing polymer valves. Here, the objectives are to demonstrate the feasibility of modifying a commercial pulse duplicator to accommodate tri-leaflet geometries and to define a protocol to present polymer valve hydrodynamic data in comparison to native and prosthetic valve data collected under near-identical conditions.

Protocollo per la relativa valutazione idrodinamica del Tri-volantino Polymer Valvole

Limitations of currently available prosthetic valves, xenografts, and homografts have prompted a recent resurgence of developments in the area of ...

Ricerca

Bioingegneria

Surgical Technique for the Implantation of Tissue Engineered Vascular Grafts and Subsequent In Vivo Monitoring

The development of Tissue Engineered Vessels (TEVs) is advanced by the ability to routinely and effectively implant TEVs (4-5 mm in diameter) into a large animal model. A step by-step protocol for inter-positional placement of the TEV and real-time digital assessment of the TEV and native carotid arteries is described here. In vivo monitoring is made possible by the implantation of flow probes, catheters and ultrasonic crystals (capable of recording dynamic diameter changes of implanted TEVs and native carotid arteries) at the time of surgery. Once implanted, researchers can calculate arterial blood flow patterns, invasive blood pressure and artery diameter yielding parameters such as pulse wave velocity, augmentation index, pulse pressures and compliance. Data acquisition is accomplished using a single computer program for analysis throughout the duration of the experiment. Such invaluable data provides insight into TEV matrix remodeling, its resemblance to native/sham controls and overall TEV performance in vivo.

Surgical Technique for the Implantation of Tissue Engineered Vascular Grafts and Subsequent In Vivo Monitoring

A step-by-step protocol for the inter-positional placement of Tissue Engineered Vessels (TEVs) into the carotid artery of a sheep using end-to-end anastomosis and real-time digital assessment in vivo until animal sacrifice.

Tecnica chirurgica per l&#39;impianto di ingegneria tessutale vascolari Innesti e successive<em&gt; In Vivo</em&gt; Monitoraggio

The development of Tissue Engineered Vessels (TEVs) is advanced by the ability to routinely and effectively implant TEVs (4-5 mm in diameter) into a large ...

Generation of a Three-dimensional Full Thickness Skin Equivalent and Automated Wounding

In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models reflect the human wound situation better than animal models. Although two-dimensional models are widely used to investigate processes such as cellular migration and proliferation, models that are more complex are required to gain a deeper knowledge about wound healing. Besides a suitable model system, the generation of precise and reproducible wounds is crucial to ensure comparable results between different test runs. In this study, the generation of a three-dimensional full thickness skin equivalent to study wound healing is shown. The dermal part of the models is comprised of human dermal fibroblast embedded in a rat-tail collagen type I hydrogel. Following the inoculation with human epidermal keratinocytes and consequent culture at the air-liquid interface, a multilayered epidermis is formed on top of the models. To study the wound healing process, we additionally developed an automated wounding device, which generates standardized wounds in a sterile atmosphere.

The goal of this protocol is to build up a three-dimensional full thickness skin equivalent, which resembles natural skin. With a specifically constructed automated wounding device, precise and reproducible wounds can be generated under maintenance of sterility.

Generazione di una tridimensionale a tutto spessore della pelle Equivalent e Automated Ferimento

In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models ...

Production, Characterization and Potential Uses of a 3D Tissue-engineered Human Esophageal Mucosal Model

The incidence of both esophageal adenocarcinoma and its precursor, Barrett&#8217;s Metaplasia, are rising rapidly in the western world. Furthermore esophageal adenocarcinoma generally has a poor prognosis, with little improvement in survival rates in recent years. These are difficult conditions to study and there has been a lack of suitable experimental platforms to investigate disorders of the esophageal mucosa.
A model of the human esophageal mucosa has been developed in the MacNeil laboratory which, unlike conventional 2D cell culture systems, recapitulates the cell-cell and cell-matrix interactions present in vivo and produces a mature, stratified epithelium similar to that of the normal human esophagus. Briefly, the model utilizes non-transformed normal primary human esophageal fibroblasts and epithelial cells grown within a porcine-derived acellular esophageal scaffold. Immunohistochemical characterization of this model by CK4, CK14, Ki67 and involucrin staining demonstrates appropriate recapitulation of the histology of the normal human esophageal mucosa.
This model provides a robust, biologically relevant experimental model of the human esophageal mucosa. It can easily be manipulated to investigate a number of research questions including the effectiveness of pharmacological agents and the impact of exposure to environmental factors such as alcohol, toxins, high temperature or gastro-esophageal refluxate components. The model also facilitates extended culture periods not achievable with conventional 2D cell culture, enabling, inter alia, the study of the impact of repeated exposure of a mature epithelium to the agent of interest for up to 20 days. Furthermore, a variety of cell lines, such as those derived from esophageal tumors or Barrett&#8217;s Metaplasia, can be incorporated into the model to investigate processes such as tumor invasion and drug responsiveness in a more biologically relevant environment.

This manuscript describes the production, characterization and potential uses of a tissue engineered 3D esophageal construct prepared from normal primary human esophageal fibroblast and squamous epithelial cells seeded within a de-cellularized porcine scaffold. The results demonstrate the formation of a mature stratified epithelium similar to the normal human esophagus.

Produzione, caratterizzazione e possibilità di utilizzo di un 3D tissutale umano esofageo mucose Modello

The incidence of both esophageal adenocarcinoma and its precursor, Barrett&#8217;s Metaplasia, are rising rapidly in the western world. Furthermore ...

A Combined 3D Tissue Engineered In Vitro/In Silico Lung Tumor Model for Predicting Drug Effectiveness in Specific Mutational Backgrounds

In the present study, we combined an in vitro 3D lung tumor model with an in silico model to optimize predictions of drug response based on a specific mutational background. The model is generated on a decellularized porcine scaffold that reproduces tissue-specific characteristics regarding extracellular matrix composition and architecture including the basement membrane. We standardized a protocol that allows artificial tumor tissue generation within 14 days including three days of drug treatment. Our article provides several detailed descriptions of 3D read-out screening techniques like the determination of the proliferation index Ki67 staining&#39;s, apoptosis from supernatants by M30-ELISA and assessment of epithelial to mesenchymal transition (EMT), which are helpful tools for evaluating the effectiveness of therapeutic compounds. We could show compared to 2D culture a reduction of proliferation in our 3D tumor model that is related to the clinical situation. Despite of this lower proliferation, the model predicted EGFR-targeted drug responses correctly according to the biomarker status as shown by comparison of the lung carcinoma cell lines HCC827 (EGFR -mutated, KRAS wild-type) and A549 (EGFR wild-type, KRAS-mutated) treated with the tyrosine-kinase inhibitor (TKI) gefitinib. To investigate drug responses of more advanced tumor cells, we induced EMT by long-term treatment with TGF-beta-1 as assessed by vimentin/pan-cytokeratin immunofluorescence staining. A flow-bioreactor was employed to adjust culture to physiological conditions, which improved tissue generation. Furthermore, we show the integration of drug responses upon gefitinib treatment or TGF-beta-1 stimulation - apoptosis, proliferation index and EMT - into a Boolean in silico model. Additionally, we explain how drug responses of tumor cells with a specific mutational background and counterstrategies against resistance can be predicted. We are confident that our 3D in vitro approach especially with its in silico expansion provides an additional value for preclinical drug testing in more realistic conditions than in 2D cell culture.

A Combined 3D Tissue Engineered In Vitro/In Silico Lung Tumor Model for Predicting Drug Effectiveness in Specific Mutational Backgrounds

We present a three-dimensional (3D) lung cancer model based on a biological collagen scaffold to study sensitivity towards non-small-cell-lung-cancer-(NSCLC)-targeted therapies. We demonstrate different read-out techniques to determine the proliferation index, apoptosis and epithelial-mesenchymal transition (EMT) status. Collected data are integrated into an in silico model for prediction of drug sensitivity.

Un Tessuto 3D combinata Engineered<em&gt; In Vitro</em&gt; /<em&gt; In Silico</em&gt; Polmone tumore per predire l&#39;efficacia della droga in specifici Sfondi mutazionali

In the present study, we combined an in vitro 3D lung tumor model with an in silico model to optimize predictions of drug response based on a specific ...

Applications of In Vivo Functional Testing of the Rat Tibialis Anterior for Evaluating Tissue Engineered Skeletal Muscle Repair

Despite the regenerative capacity of skeletal muscle, permanent functional and/or cosmetic deficits (e.g., volumetric muscle loss (VML) resulting from traumatic injury, disease and various congenital, genetic and acquired conditions are quite common. Tissue engineering and regenerative medicine technologies have enormous potential to provide a therapeutic solution. However, utilization of biologically relevant animal models in combination with longitudinal assessments of pertinent functional measures are critical to the development of improved regenerative therapeutics for treatment of VML-like injuries. In that regard, a commercial muscle lever system can be used to measure length, tension, force and velocity parameters in skeletal muscle. We used this system, in conjunction with a high power, bi-phase stimulator, to measure in vivo force production in response to activation of the anterior crural compartment of the rat hindlimb. We have previously used this equipment to assess the functional impact of VML injury on the tibialis anterior (TA) muscle, as well as the extent of functional recovery following treatment of the injured TA muscle with our tissue engineered muscle repair (TEMR) technology. For such studies, the left foot of an anaesthetized rat is securely anchored to a footplate linked to a servomotor, and the common peroneal nerve is stimulated by two percutaneous needle electrodes to elicit muscle contraction and dorsiflexion of the foot. The peroneal nerve stimulation-induced muscle contraction is measured over a range of stimulation frequencies (1-200 Hz), to ensure an eventual plateau in force production that allows for an accurate determination of peak tetanic force. In addition to evaluation of the extent of VML injury as well as the degree of functional recovery following treatment, this methodology can be easily applied to study diverse aspects of muscle physiology and pathophysiology. Such an approach should assist with the more rational development of improved therapeutics for muscle repair and regeneration.

Applications of In Vivo Functional Testing of the Rat Tibialis Anterior for Evaluating Tissue Engineered Skeletal Muscle Repair

We describe an in vivo protocol to measure dorsiflexion of the foot following stimulation of the peroneal nerve and contraction of the anterior crural compartment of the rat hindlimb. Such measurements are an indispensable translational tool for evaluating skeletal muscle pathology and tissue engineering approaches to muscle repair and regeneration.

applicazioni di<em&gt; In Vivo</em&gt; Test funzionale del Topo tibiale anteriore per la valutazione di ingegneria tessutale muscolo scheletrico di riparazione

Despite the regenerative capacity of skeletal muscle, permanent functional and/or cosmetic deficits (e.g., volumetric muscle loss (VML) resulting from ...

Three-dimensional Tissue Engineered Aligned Astrocyte Networks to Recapitulate Developmental Mechanisms and Facilitate Nervous System Regeneration

Neurotrauma and neurodegenerative disease often result in lasting neurological deficits due to the limited capacity of the central nervous system (CNS) to replace lost neurons and regenerate axonal pathways. However, during nervous system development, neuronal migration and axonal extension often occur along pathways formed by other cells, referred to as &#34;living scaffolds&#34;. Seeking to emulate these mechanisms and to design a strategy that circumvents the inhibitory environment of the CNS, this manuscript presents a protocol to fabricate tissue engineered astrocyte-based &#34;living scaffolds&#34;. To create these constructs, we employed a novel biomaterial encasement scheme to induce astrocytes to self-assemble into dense three-dimensional bundles of bipolar longitudinally-aligned somata and processes. First, hollow hydrogel micro-columns were assembled, and the inner lumen was coated with collagen extracellular-matrix. Dissociated cerebral cortical astrocytes were then delivered into the lumen of the cylindrical micro-column and, at a critical inner diameter of &#60;350 &#181;m, spontaneously self-aligned and contracted to produce long fiber-like cables consisting of dense bundles of astrocyte processes and collagen fibrils measuring &#60;150 &#181;m in diameter yet extending several cm in length. These engineered living scaffolds exhibited &#62;97% cell viability and were virtually exclusively comprised of astrocytes expressing a combination of the intermediate filament proteins glial-fibrillary acidic protein (GFAP), vimentin, and nestin. These aligned astrocyte networks were found to provide a permissive substrate for neuronal attachment and aligned neurite extension. Moreover, these constructs maintain integrity and alignment when extracted from the hydrogel encasement, making them suitable for CNS implantation. These preformed constructs structurally emulate key cytoarchitectural elements of naturally occurring glial-based &#34;living scaffolds&#34; in vivo. As such, these engineered living scaffolds may serve as test-beds to study neurodevelopmental mechanisms in vitro or facilitate neuroregeneration by directing neuronal migration and/or axonal pathfinding following CNS degeneration in vivo.

We showcase the development of self-assembled, three-dimensional bundles of longitudinally aligned astrocytic somata and processes within a novel biomaterial encasement. These engineered &#34;living scaffolds&#34;, exhibiting micron-scale diameter yet extending centimeters in length, may serve as test-beds to study neurodevelopmental mechanisms or facilitate neuroregeneration by directing neuronal migration and/or axonal pathfinding.

Tessutale tridimensionale allineato Astrocyte reti per ricapitolare i meccanismi dello sviluppo e facilitare la rigenerazione del sistema nervoso

Neurotrauma and neurodegenerative disease often result in lasting neurological deficits due to the limited capacity of the central nervous system (CNS) to ...

A Novel Tenorrhaphy Suture Technique with Tissue Engineered Collagen Graft to Repair Large Tendon Defects

Surgical management of large tendon defects with tendon grafts is challenging, as there are a finite number of sites where donors can be readily identified and used. Currently, this gap is filled with tendon auto-, allo-, xeno-, or artificial grafts, but clinical methods to secure them are not necessarily translatable to animals because of the scale. In order to evaluate new biomaterials or study a tendon graft made up of collagen type 1, we have developed a modified suture technique to help maintain the engineered tendon in alignment with the tendon ends. Mechanical properties of these grafts are inferior to the native tendon. To incorporate engineered tendon into clinically relevant models of loaded repair, a strategy was adopted to offload the tissue engineered tendon graft and allow for the maturation and integration of the engineered tendon in vivo until a mechanically sound neo-tendon was formed. We describe this technique using incorporation of the collagen type 1 tissue engineered tendon construct.

In this paper, we present an in vitro and in situ protocol to repair a tendon gap of up to 1.5 cm by filling it with engineered collagen graft. This was performed by developing a modified suture technique to take the mechanical load until the graft matures into the host tissue.

Una nuova tecnica di sutura Tenorrhaphy con innesto di collagene ingegnerizzato per riparare grandi difetti tendinei

Surgical management of large tendon defects with tendon grafts is challenging, as there are a finite number of sites where donors can be readily ...

Seeding and Implantation of a Biosynthetic Tissue-engineered Tracheal Graft in a Mouse Model

Treatment options for congenital or secondary long segment tracheal defects have historically been limited due to an inability to replace functional tissue. Tissue engineering holds great promise as a potential solution with its ability to integrate cells and signaling molecules into a 3-dimensional scaffold. Recent work with tissue engineered tracheal grafts (TETGs) has seen some success but their translation has been limited by graft stenosis, graft collapse, and delayed epithelialization. In order to investigate the mechanisms driving these issues, we have developed a mouse model for tissue engineered tracheal graft implantation. TETGs were constructed using electrospun polymers polyethylene terephthalate (PET) and polyurethane (PU) in a mixture of PET and PU (20:80 percent weight). Scaffolds were then seeded using bone marrow mononuclear cells isolated from 6-8 week-old C57BL/6 mice by gradient centrifugation. Ten million cells per graft were seeded onto the lumen of the scaffold and allowed to incubate overnight before implantation between the third and seventh tracheal rings. These grafts were able to recapitulate the findings of stenosis and delayed epithelialization as demonstrated by histological analysis and lack of Keratin 5 and Keratin 14 basal epithelial cells on immunofluorescence. This model will serve as a tool for investigating cellular and molecular mechanisms involved in host remodeling.

Graft stenosis poses a critical obstacle in tissue engineered airway replacement. To investigate cellular mechanisms underlying stenosis, we utilize a murine model of tissue engineered tracheal replacement with seeded bone marrow mononuclear cells (BM-MNC). Here, we detail our protocol, including scaffold manufacturing, BM-MNC isolation, graft seeding, and implantation.

Semina e impianto di un innesto trachea tessutale biosintetico in un modello murino

Treatment options for congenital or secondary long segment tracheal defects have historically been limited due to an inability to replace functional ...

Tissue-Engineered Graft for Circumferential Esophageal Reconstruction in Rats

The use of biocompatible materials for circumferential esophageal reconstruction is a technically challenging task in rats and requires an optimal implant technique with nutritional support. Recently, there have been many attempts at esophageal tissue engineering, but the success rate has been limited due to difficulty in early epithelization in the special environment of peristalsis. Here, we developed an artificial esophagus that can improve the regeneration of the esophageal mucosa and muscle layers through a two-layered tubular scaffold, a mesenchymal stem cell-based bioreactor system, and a bypass feeding technique with modified gastrostomy. The scaffold is made of polyurethane (PU) nanofibers in a cylindrical shape with a three-dimensional (3D) printed polycaprolactone strand wrapped around the outer wall. Prior to transplantation, human-derived mesenchymal stem cells were seeded into the lumen of the scaffold, and bioreactor cultivation was performed to enhance cellular reactivity. We improved the graft survival rate by applying surgical anastomosis and covering the implanted prosthesis with a thyroid gland flap, followed by temporary nonoral gastrostomy feeding. These grafts were able to recapitulate the findings of initial epithelialization and muscle regeneration around the implanted sites, as demonstrated by histological analysis. In addition, increased elastin fibers and neovascularization were observed in the periphery of the graft. Therefore, this model presents a potential new technique for circumferential esophageal reconstruction.

Esophageal reconstruction is a challenging procedure, and development of a tissue-engineered esophagus that enables regeneration of esophageal mucosa and muscle and that can be implanted as an artificial graft is necessary. Here, we present our protocol to generate an artificial esophagus, including scaffold manufacturing, bioreactor cultivation, and various surgical techniques.

Innesto ingegnerizzato per la ricostruzione esofagea circonferenza nei ratti

The use of biocompatible materials for circumferential esophageal reconstruction is a technically challenging task in rats and requires an optimal implant ...