Este trabalho foi apoiado por subvenções do NHMRC e Stafford Fox Fundação Médica. Os autores reconhecem a assistência cirúrgica de Sue McKay, Liliana Pepe, Anna Deftereos e Amanda Rixon do Experimental Médica e Unidade Cirúrgica do Hospital de St. Vincent, Melbourne. O suporte também é fornecido pelo Departamento de Inovação, Indústria do Governo do Estado de Victoria e Programa de Apoio à infra-estrutura operacional do Desenvolvimento Regional.

Os protocolos aqui descritos foram aprovados pelo Comitê de Ética Animal de St. Vincent Hospital Melbourne, Austrália, e foram conduzidos em estrita observância às orientações australianos Conselho Nacional de Saúde e Pesquisa Médica. NOTA: Dois protocolos de câmara são descritos abaixo. Os dois modelos diferentes e os seus modelos específicos de câmara são ilustradas na Figura 1. Câmara (1) é feita de policarbonato (para o modelo de rato câmara anelar arteriovenosa). Ele é cilíndrico com um diâmetro interno de 13 mm e altura de 4 mm. Uma janela em um ponto na parede permite o acesso desimpedido para o pedículo. No segundo modelo (por fluxo através de rato modelo de câmara de pedículo), a câmara é feita de poliacrílico e é rectangular (10 x as dimensões de 8 x 4 mm3 internos). Ele tem duas aberturas de 1,5 mm em lados opostos para acomodar a artéria e veia femoral à medida que a câmara de transgredir. 1. Modelo Câmara Rat arteriovenosa Loop (Uma Chamber por animal) NOTA: Antes de iniciar a cirurgia, certifique-se de todos os instrumentos foram devidamente esterilizados. Da mesma forma, garantir o resto instrumentos em toalhas estéreis e estão a uma distância razoável do campo cirúrgico para evitar a contaminação durante o procedimento. <ol><li> Preparação do animal para a cirurgia <ol><li> Use ratos pesando pelo menos 250 g por seu grande tamanho dos vasos para a criação da alça arteriovenosa. </li><li> Anestesiar os animais com 4% inalação de isoflurano. Corroboram profundidade adequada da anestesia, avaliando a ausência de resposta aos pés-pitada. Após a anestesia, o animal manter adequadamente anestesiados durante todo o procedimento com 2% de isoflurano. </li><li> Colocar o animal numa posição supina sobre uma almofada de aquecimento e aplicar lubrificante estéril para os olhos para prevenir a dessecação durante a cirurgia. </li><li> Usando um barbeador elétrico, fazer a barba ambos os virilhas e remover o cabelo com um pedaço de gaze úmida. </li><li> Preparar os locais cirúrgicos com clorexidinasolução de etanol / 70% e armar o animal com toalhas estéreis. Administrar uma dose única de carprofeno (5 mg / kg, subcutaneamente) como analgésico. </li></ol></li><li> Colheita da veia femoral do enxerto <ol><li> Usando uma lâmina # 15, fazer uma incisão na pele de 4 cm de comprimento na virilha esquerdo paralelo ao ligamento inguinal. Isso expõe a almofada de gordura inguinal. </li><li> Cortar a almofada de gordura em circunferência com uma tesoura deixá-lo ligado ao seu pedículo vascular baseado nos vasos epigástricos. </li><li> Usando micro tesouras, libertar os filmy aderências do tecido conjuntivo entre a parede abdominal e os vasos femorais subjacentes. </li><li> Coloque um afastador na parede abdominal e puxe medial. Isso expõe o ligamento inguinal e de todo o comprimento dos vasos femorais. </li><li> Usando micro pinça e tesoura curva dissecar a veia epigástrica e isolá-lo a partir da sua gordura ao redor puxando e corte com cuidado. Esta veia atua como uma corda ao construir o loop. </li><li> using micro fórceps e curvas tesoura micro abrir a bainha perivascular contendo os vasos femorais e nervo todo o caminho desde o ligamento inguinal à sua distal bifurcação para o ramo epigástrica. </li><li> Usando micro fórceps, pegar a veia femoral pela sua adventícia e gentilmente separá-lo dos tecidos circundantes e acompanhando artéria. Faça isso com micro fórceps e curvas tesoura micro apontou-redondas, puxando o tecido distante e cortando-o. NOTA: Não agarrar toda a espessura da parede da veia, pois isso poderia causar trauma para a íntima tornando-se propensos a trombose. </li><li> ramos laterais ligar encontrados durante a dissecção com sutura 10/0 nylon ou coagular-los com um coagulador bipolar. </li><li> Com a veia femoral completamente livre, ligar sua extremidades proximal e distal com suturas de seda 4/0. Certifique-se de obter um enxerto de veia de comprimento, pelo menos, 10 mm e incluem aproximadamente 0,5 cm de comprimento do ramo epigástrica para ser utilizado como um grupo de ancoragem cara cordapara manter a malha aberta na câmara. </li><li> Usando micro fórceps e micro tesoura reta, cortar a adventícia das extremidades do enxerto puxando e corte com cuidado. Isso também pode ser feito mais tarde, antes de anastomoses microcirúrgicas. </li><li> Lave o enxerto de veia com solução salina heparinizada (10 U / ml de heparina) e deixe-a descansar na solução. Fechar a ferida usando corrida contínua 4/0 fio de seda e mais dois ou três pontos isolados simples adicionais. </li></ol></li><li> Criação de arteriovenosa laço e Implantação de Câmara <ol><li> Repita os passos 1.2.1 a 1.2.4 no exatamente da mesma maneira no membro contralateral. </li><li> Usando micro fórceps, dissecar e isolar tanto a artéria epigástrica e veia formar a almofada de gordura ao redor. Para fazer isso, puxando suavemente o tecido longe dos vasos </li><li> Usando micro fórceps, pegar a artéria femoral pela sua adventícia e libertá-la dos tecidos circundantes. Faça isso com micro fórceps e mic pontas round-curvadatesouras ro puxando o tecido distante e cortando-o. Ligadura ou coagular seus ramos laterais. </li><li> Ligar a artéria e veia femoral distai para o surgimento dos vasos epigástricas usando sutura de seda 4/0. </li><li> Colocar uma única braçadeira proximal em cada uma das artéria e veia femorais. Usando um micro tesoura reta afiada, faça um transversal limpo cortado em cada distal navio para a emergência dos ramos epigástrica. Coloque um fundo de contraste de plástico estéril sob os vasos. </li><li> Lave os vasos vigorosamente com generosas quantidades de soro fisiológico heparinizado até que todo o sangue é removido a partir do lúmen. </li><li> Trazer o enxerto de veia no campo operatório e remover qualquer adventícia redundante das extremidades dos navios, como por etapa 1.2.10, se necessário. </li><li> Realizar as duas anastomoses microcirúrgicas com sutura 10/0 nylon. Anastomose da extremidade proximal do enxerto de veia para a veia femoral e a extremidade distai à artéria femoral. Isto irá permitir que o sangue flua fROM arterial para o lado venoso sem resistência de válvulas no interior do enxerto de veia. NOTA: Certifique-se os vasos femorais e o enxerto de veia resto na sua posição natural, sem quaisquer torções. </li><li> Verifique se há vazamentos em ambos os locais de anastomose. Resolver pequenos vazamentos, que parecem não pulsátil de sangue que sai do local da anastomose, colocando um pequeno pedaço de gordura na parte superior e que comprime suavemente durante 5-10 min. Maiores vazamentos pulsantes que rapidamente inundar o campo inteiro vai precisar de pontos adicionais. </li><li> Verifique desobstrução da alça arteriovenosa. oclusão suave da artéria femural deve torná-lo enquanto o mesmo encolher na veia femural deve absorver lo. </li><li> Coloque a base da câmara de engenharia de tecidos sob o loop arteriovenosa com este último na sua posição de repouso natural, sem torções ou torções. </li><li> Fixe a base da câmara ao ligamento inguinal e da fáscia muscular subjacente com 6/0 suturas de nylon. </li><li> Coloque a tampa sobre obase, de modo que os vasos femorais entrar na câmara através de um entalhe (janela no lado da câmara). Ao fechar a tampa, certifique-se que ele pega os ramos epigástricas, entre a base da câmara e tampa, que agem como amarras para segurar a alça arteriovenosa na posição. </li><li> Fechar a ferida usando corrida contínua 4/0 fio de seda e mais dois ou três pontos isolados simples adicionais. </li><li> Permitir ao animal recuperar da anestesia em uma almofada de aquecimento. </li><li> Não deixe o animal sem supervisão até que tenha recuperado a consciência suficiente para manter decúbito esternal. Da mesma forma, não devolva um animal que foi submetido a uma cirurgia para a companhia de outros animais até que esteja totalmente recuperado. 24 horas mais tarde, administrar outra dose única de carprofeno (5 mg / kg, subcutaneamente) como analgésico. </li><li> Tratar a ferida com pomada antibiótica tópica durante 5 dias. Se a ferida é aberta, anestesiar o animal como no passo 1.1.2 1.1.5 através e fechar a ferida como no ponto 1.3.14. Monitorar a saúde de animais diariamente. Eutanásia do animal utilizando uma dose letal de injecção lethabarb intraperitoneal (163 mg / kg, em 0,25 ml de 23 agulha G) se o animal apresentar mais do que um dos sinais moderados inacitivity, falta de apetite, perda de peso e perda de cor. </li></ol></li></ol> 2. flow-through Pedicle Câmara (duas câmaras por animal) <ol><li> Preparação do animal para a cirurgia <ol><li> Repita os passos 1.1.1 até 1.1.4. Duas câmaras pode ser implantado em ambas as regiões inguinais de um único rato. </li></ol></li><li> Isolamento de vasos femorais e Inserção da Câmara <ol><li> Repita os passos 1.2.1 através de 1.2.8. </li><li> Com ambos artéria e veia completamente livre de tecidos circundantes e seus ramos ligados, traga a câmara para o campo operatório. </li><li> Coloque cada um dos vasos femorais intactas na fenda correspondente da base da câmara de certificando-se de que não haja torções ou torções. </li><li> Feche a câmara por attaching a tampa à base. Fechar a ferida usando uma corrida contínua 4/0 sutura de seda mais dois ou três pontos separados adicionais simples e permitir que o animal recuperar, como descrito anteriormente. </li></ol></li></ol> 3. Colheita de Chambers e processamento de tecidos <ol><li> Uma vez que os pontos de tempo do experimento (4-6 semanas pós-implantação) são atingidas, anestesiar o animal como no passo 1.1.2 e repita os passos 1.1.3 através de 1.1.5. </li><li> Abrir a ferida usando uma lâmina de # 15 e a atravessar os tecidos com tesouras até que a câmara está completamente exposta. </li><li> Expor os vasos femorais proximais para a construção e teste de permeabilidade vascular: suavemente ocluir o vaso com duas micropinças, em seguida, o leite do sangue numa direcção distal e finalmente soltar a pinça proximal. Se o navio se enche de sangue novo, isto confirma a permeabilidade. Ligadura os vasos femorais proximalmente no caso de o circuito arteriovenoso e proximal e distalmente no caso de the por escoamento de configuração e eliminar as câmaras com o tecido contendo em bloco. </li><li> No final da experiência, a eutanásia dos animais utilizando uma dose letal de injecção lethobarb intraperitoneal (163 mg / kg em 0,25 ml por 23 L de agulha). </li><li> Fix tecidos em 4% de paraformaldeído à temperatura ambiente durante 24 h. Divide tecidos em várias secções transversais (1-2 mm de espessura) e incorporar em cera de parafina ou composto óptima temperatura de corte de secções de parafina (5 uM) ou secções congeladas (10 fim), respectivamente. 3,4,8,17,22, 24 </li><li> Realizar a coloração histológica de rotina, tais como hematoxilina e eosina para examinar a morfologia geral de tecidos. Execute coloração imuno-histoquímica com anticorpo específico para identificar o tipo de célula de interesse, 3,4,8,17,22,24,29 para a imunocoloração T exemplo troponina em cardiomiócitos. </li></ol>

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K., Cassell, O. C., Kelly, J., Abberton, K. M., Morrison, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+a+vascularized+organoid+using+skeletal+muscle+as+the+inductive+source.">Generation of a vascularized organoid using skeletal muscle as the inductive source.</a> FASEB J. 19 (11), 1570-1572 (2005).</li><li>Lim, S. Y., Hern&#225;ndez, D., Dusting, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Growing+vascularized+heart+tissue+from+stem+cells.">Growing vascularized heart tissue from stem cells.</a> J Cardiovasc Pharmacol. 62 (2), 122-129 (2013).</li><li>Poon, C. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+an+adipogenic+hydrogel+from+subcutaneous+adipose+tissue.">Preparation of an adipogenic hydrogel from subcutaneous adipose tissue.</a> Acta Biomater. 9 (3), 5609-5620 (2013).</li><li>Dilley, R. J., Morrison, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vascularisation+to+improve+translational+potential+of+tissue+engineering+systems+for+cardiac+repair.">Vascularisation to improve translational potential of tissue engineering systems for cardiac repair.</a> Int J Biochem Cell Biol. 56, 38-46 (2014).</li><li>Lesman, A., Koffler, J., Atlas, R., Blinder, Y. J., Kam, Z., Levenberg, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+vessel-like+networks+within+multicellular+fibrin-based+constructs.">Engineering vessel-like networks within multicellular fibrin-based constructs.</a> Biomaterials. 32 (31), 7856-7869 (2011).</li><li>Hussey, A. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Seeding+of+pancreatic+islets+into+prevascularized+tissue+engineering+chambers.">Seeding of pancreatic islets into prevascularized tissue engineering chambers.</a> Tissue Eng Part A. 15 (12), 3823-3833 (2009).</li><li>Chen, X., Aledia, A. S., Popson, S. A., Him, L., Hughes, C. C., George, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+anastomosis+of+endothelial+progenitor+cell-derived+vessels+with+host+vasculature+is+promoted+by+a+high+density+of+cotransplanted+fibroblasts.">Rapid anastomosis of endothelial progenitor cell-derived vessels with host vasculature is promoted by a high density of cotransplanted fibroblasts.</a> Tissue Eng Part A. 16 (2), 585-594 (2010).</li><li>Lin, R. Z., Melero-Martin, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fibroblast+growth+factor-2+facilitates+rapid+anastomosis+formation+between+bioengineered+human+vascular+networks+and+living+vasculature.">Fibroblast growth factor-2 facilitates rapid anastomosis formation between bioengineered human vascular networks and living vasculature.</a> Methods. 56 (3), 440-451 (2012).</li><li>Dolderer, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spontaneous+large+volume+adipose+tissue+generation+from+a+vascularized+pedicled+fat+flap+inside+a+chamber+space.">Spontaneous large volume adipose tissue generation from a vascularized pedicled fat flap inside a chamber space.</a> Tissue Eng. 13 (4), 673-681 (2007).</li><li>Wei, F. C., Lin Tay, S. K., Neligan, P. C., Gurtner, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Principles+and+techniques+of+microvascular+surgery.">Principles and techniques of microvascular surgery.</a> Plastic Surgery. Volume 1. , 587-620 (2013).</li><li>Sekine, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+fabrication+of+functional+three-dimensional+tissues+with+perfusable+blood+vessels.">In vitro fabrication of functional three-dimensional tissues with perfusable blood vessels.</a> Nat.Comm. 4 (1399), 1-10 (2013).</li><li>Lim, S. Y., Sivakumaran, P., Crombie, D. E., Dusting, G. J., P&#233;bay, A., Dilley, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trichostatin+A+enhances+differentiation+of+human+induced+pluripotent+stem+cells+to+cardiogenic+cells+for+cardiac+tissue+engineering.">Trichostatin A enhances differentiation of human induced pluripotent stem cells to cardiogenic cells for cardiac tissue engineering.</a> Stem Cells Transl Med. 2 (9), 715-725 (2013).</li><li>Lim, S. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+tissue+engineering+chamber+supports+human+induced+pluripotent+stem+cell+survival+and+rapid+differentiation.">In vivo tissue engineering chamber supports human induced pluripotent stem cell survival and rapid differentiation.</a> Biochem Biophys Res Commun. 422 (1), 75-79 (2012).</li><li>Piao, Y., Hung, S. S., Lim, S. Y., Wong, R. C., Ko, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+generation+of+integration-free+human+induced+pluripotent+stem+cells+from+keratinocytes+by+simple+transfection+of+episomal+vectors.">Efficient generation of integration-free human induced pluripotent stem cells from keratinocytes by simple transfection of episomal vectors.</a> Stem Cells Transl Med. 3 (7), 787-791 (2014).</li></ol>

Os autores declaram não haver interesses concorrentes.

Engenharia da microcirculação está sendo investigado, essencialmente através de duas abordagens. A primeira envolve o desenvolvimento de uma rede vascular altamente interligada dentro da construção in vitro de modo a que, quando implantados, os capilares do leito vascular hospedeiro ligar com aqueles do transplantado construir através de um processo chamado inosculation, garantindo assim a entrega de nutrientes, não só para a periferia mas também para o núcleo. 21,32,33 Isto é chamado de ...

Fabricação de tecido vascularizado funcional, utilizando uma abordagem de engenharia de tecidos é um paradigma emergente na medicina regenerativa. 1,2 Muitas abordagens para projetar o tecido novo e saudável para a substituição de tecido lesionado ou órgãos defeituosos têm sido desenvolvidos, 3-6 experimentalmente em modelos animais pequenos com promissor potencial clínico 7,8. No entanto, a vascularização continua a ser um dos maiores desafios para a engenharia de tecidos que limitam o seu potencial de crescimento de tecidos tamanho clinicamente relevante. 9 As abordagens actuais para vascularizar tecidos seguir qualquer uma via extrínseca, onde novos vasos crescem a partir do leito vascular destinatário e invadir durante todo o tecido implantado constrói 10 ou uma via de vascularização intrínseca, onde a vasculatura cresce e se expande em uníssono com o tecido acabado de desenvolvimento. 11 A abordagem extrínseca tradicionalmente envolve as células de semeadura em um andaimein vitro e implantando a construção completa para o animal vivo com a expectativa de que os nutrientes, previamente fornecido pelo meio de cultura, será obtida a partir da circulação. 12,13 O conceito é simplista como ingressos vascular é muito lento e apenas implantes muito finas (&lt; 1-2 mm de espessura) permanecerá viável. Fornecendo nutrientes e oxigênio através de uma vascularização suficiente e rápida é o cerne de todas as tentativas de sucesso para crescer substitutos mais complexos e maiores da engenharia de tecidos, como ossos, músculos, gordura e órgãos sólidos. 14,15 vascularização Intrinsic oferece o potencial para construções maiores para desenvolver pelo crescimento tecidual progressiva à altura do seu fornecimento de sangue em expansão. Um projeto é a implantação in vivo em uma câmara de um pedículo vascular, com ou sem um andaime semeado celular. 5,6 Isso abriu o caminho para novos procedimentos para a geração de mais grossos tecidos intrinsecamente vascularizados 16,17. &lt;/ P&gt; Mais recentemente, as estratégias têm sido desenvolvidos para enxertos de tecidos, antes da implantação-vascularizar previamente. Estas redes de vasos sanguíneos incorporados são destinados a unir com os vasos do hospedeiro ao implante permitindo o rápido fornecimento de um suprimento de sangue completo para melhorar a sobrevivência de todas as partes de um enxerto de tecido grosso transplantado 18. Nós pioneira um modelo de engenharia de tecidos in vivo vascularizado em pequenos animais que envolve uma câmara fechada semi-rígida implantadas subcutaneamente contendo um pedículo vascular perfundido e biomateriais contendo as células. A câmara cria um ambiente isquémico que estimula a germinação angiogénica dos vasos implantados. 3 O pedículo vascular pode ser um circuito arteriovenoso reconstruída ou uma artéria de fluxo intacto e veia. 3-6,19 A vasculares couves pediculares um funcionamento e um grande artério rede -capillary-venosa que liga tanto a arteeriole e venosa termina com o pedículo vascular. 3,20 Além disso, a câmara de suporte oco envolvente protege o tecido em desenvolvimento de potencialmente deformando forças mecânicas e prolonga a unidade isquêmico para melhorar a vascularização. 3,21,22 Se o pedículo embarcação é simplesmente implantados em tecido normal e não dentro do espaço protegido da câmara, surgimento angiogênico deixa ao longo da mesma linha do tempo como uma ferida normal e nenhum novo tecido irá acumular em torno do pedículo. Os investigadores usaram esta configuração in vivo para produzir tridimensionais construções de tecido vascularizado funcionais com vasculatura de suporte e de tamanho clinicamente relevante. 4,23 Além disso, as construções de tecido vascularizado artificiais, com a sua pedículo vascular intacta pode ser colhida para transplante subsequente no local da lesão 24,25. Um cenário mais clinicamente viável seria a criação da câmara no local definitivo para a reconstrução sdominam vários como o da mama. Assim, este novo abordagem de engenharia de tecidos pode ter um potencial clínico para proporcionar uma nova fonte de tecido alvo funcional para cirurgia reconstrutiva. 26-28 O protocolo que se segue irá fornecer um guia geral para a construção de uma câmara de engenharia de tecidos vascularizados in vivo no rato, que pode ser adaptada em diferentes modelos animais e utilizados para examinar o intrincado processo de angiogénese, a produção da matriz, e a migração e diferenciação celular.

<table border="0" cellpadding="0" cellspacing="0" width="649">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:123px;">1 15 Blade Scalpel</td>
			<td style="width:187px;">Braun</td>
			<td style="width:163px;">BB515</td>
			<td style="width:176px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Toothed Adson Forceps</td>
			<td>Braun</td>
			<td>BD527R</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Needle Holder</td>
			<td>Braun</td>
			<td>BM201R</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Bipolar Coagulator&#160;</td>
			<td>Braun</td>
			<td>US335</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Needle Holder B-15-8.3</td>
			<td>S &#38; T</td>
			<td>00763</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Dilator Forceps D-5a.2</td>
			<td>S &#38; T</td>
			<td>00125</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Jeweler&#39;s Forceps JF-5</td>
			<td>S &#38; T</td>
			<td>00108</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Scissors - Straight SAS-11</td>
			<td>S &#38; T</td>
			<td>00098</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Scissors - Curved SDC-11</td>
			<td>S &#38; T</td>
			<td>00090</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2 Single Clamps B-3</td>
			<td>S &#38; T</td>
			<td>00400</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2 10/0 nylon suture</td>
			<td>S &#38; T</td>
			<td>03199</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 6/0 nylon suture</td>
			<td>Braun</td>
			<td>G2095469</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2 4/0 Silk Sutures</td>
			<td>Braun</td>
			<td>C0760145</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Xilocaine 1%</td>
			<td>Dealmed</td>
			<td>150733</td>
			<td>10 mg/ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Heparin Sodium</td>
			<td>Dealmed</td>
			<td>272301</td>
			<td>5000 UI / ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ringer Lactate</td>
			<td>Baxter</td>
			<td>JB2323</td>
			<td>500 ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 dome-shaped tissue engineering chamber</td>
			<td>custom made</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1 flow-through chamber</td>
			<td>custom made</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Lectin I, Griffonia Simplicifolia&#160;</td>
			<td>Vector Laboratories</td>
			<td>B-1105</td>
			<td>1.67 &#956;g/mL</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Troponin T antibody</td>
			<td>Abcam</td>
			<td>Ab8295</td>
			<td>4 &#956;g/mL</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Human-specific Ku80 antibody</td>
			<td>Abcam</td>
			<td>Ab80592</td>
			<td style="width:176px;">0.06 &#956;g/mL</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Desmin antibody</td>
			<td>Dako</td>
			<td>M0760</td>
			<td style="width:176px;">2.55 &#956;g/mL</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">Cell Tracker CM-DiI dye</td>
			<td>Thermo Fisher Scientific</td>
			<td>C-7000</td>
			<td>3 mg/106 cells</td>
		</tr>
	</tbody>
</table>

tissue engineering by intrinsic vascularization in an in vivo tissue engineering chamber

Na cirurgia de reconstrução, há uma necessidade clínica para uma alternativa aos actuais métodos de reconstrução autólogos, que são complexos, dispendiosos e de comércio um defeito para o outro. A engenharia de tecidos mantém a promessa de abordar esta demanda crescente. No entanto, a maioria das estratégias de engenharia de tecidos não conseguem gerar substitutos de tecidos estáveis ​​e funcionais por causa da má vascularização. Este artigo centra-se em um modelo de câmara in vivo engenharia de tecidos da vascularização intrínseca, onde uma artéria e uma veia perfusão ou como um loop arteriovenosa ou uma configuração pedículo flow-through é dirigido dentro de uma câmara oca protegida. Neste sistema baseado na câmara de germinação ocorre a partir angiogénico nos vasos arteriovenosas e este sistema atrai a migração celular endógeno isquémica e inflamatório accionado que preenche o espaço gradualmente câmara com tecido fibro-vascular. células exógena / implantação matriz no momento da construção da câmara aumenta sur celularvência e determina a especificidade dos tecidos de engenharia que se desenvolvem. Os nossos estudos demonstraram que este modelo de câmara pode gerar com êxito diferentes tecidos, tais como gordura, o músculo cardíaco, fígado e outros. No entanto, são necessárias modificações e refinamentos para assegurar a formação de tecido alvo é consistente e reproduzível. Este artigo descreve um protocolo normalizado para a fabricação de dois modelos de câmara engenharia de tecidos vascularizados diferentes in vivo.

A criação de câmaras microcirúrgico em engenharia de tecido foi realizado como descrito no protocolo acima. Os tecidos geradas dentro das câmaras podem ser examinados histologicamente como descrito no passo 3. protocolo Vários tipos de tecido foram projetados com sucesso utilizando a câmara de vascularizado in vivo (Figura 2). Estas incluem tecido cardíaco com cardiomiócitos neonatais de rato (Figura 2a), o tecido do músculo esqueléti...

Watch this Scientific Journal Video about Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber at JoVE.com

Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber

This is a guideline for constructing in vivo vascularized tissue using a microsurgical arteriovenous loop or a flow-through pedicle configuration inside a tissue engineering chamber. The vascularized tissues generated can be employed for organ regeneration and replacement of tissue defects, as well as for drug testing and disease modeling.

Engenharia de Tecidos por Intrínseca Vascularização numa<em&gt; In Vivo</em&gt; Câmara Engenharia de Tecidos

In reconstructive surgery, there is a clinical need for an alternative to the current methods of autologous reconstruction which are complex, costly and ...

tissue-engineering-intrinsic-vascularization-an-vivo-tissue

Research

JoVE Journal

Bioengineering

Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber

8.8K visualizações.  St Vincent's Institute of Medical Research. This is a guideline for constructing in vivo vascularized tissue using a microsurgical arteriovenous loop or a flow-through pedicle configuration inside a tissue engineering chamber. The vascularized tissues generated can be employed for organ regeneration and replacement of tissue defects, as well as for drug testing and disease modeling. 

Vídeo: Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber

Fabrication of Biologically Derived Injectable Materials for Myocardial Tissue Engineering

This protocol provides methods for the preparation of an injectable extracellular matrix (ECM) gel for myocardial tissue engineering applications. Briefly, decellularized tissue is lyophilized, milled, enzymatically digested, and then brought to physiological pH. The lyophilization removes all water content from the tissue, resulting in dry ECM that can be ground into a fine powder with a small mill. After milling, the ECM powder is digested with pepsin to form an injectable matrix. After adjustment to pH 7.4, the liquid matrix material can be injected into the myocardium. Results of previous characterization assays have shown that matrix gels produced from decellularized pericardial and myocardial tissue retain native ECM components, including diverse proteins, peptides and glycosaminoglycans. Given the use of this material for tissue engineering, in vivo characterization is especially useful; here, a method for performing an intramural injection into the left ventricular (LV) free wall is presented as a means of analyzing the host response to the matrix gel in a small animal model. Access to the chest cavity is gained through the diaphragm and the injection is made slightly above the apex in the LV free wall. The biologically derived scaffold can be visualized by biotin-labeling before injection and then staining tissue sections with a horse radish peroxidase-conjugated neutravidin and visualizing via diaminobenzidine (DAB) staining. Analysis of the injection region can also be done with histological and immunohistochemical staining. In this way, the previously examined pericardial and myocardial matrix gels were shown to form fibrous, porous networks and promote vessel formation within the injection region.

Methods for preparing an injectable matrix gel from decellularized tissue and injecting it into rat myocardium in vivo are described.

Biologicamente fabricação de materiais derivados injetável para Engenharia de Tecidos do Miocárdio

This protocol provides methods for the preparation of an injectable extracellular matrix (ECM) gel for myocardial tissue engineering applications.  ...

Bioengenharia

Elastomeric PGS Scaffolds in Arterial Tissue Engineering

Cardiovascular disease is one of the leading cause of mortality in the US and especially, coronary artery disease increases with an aging population and increasing obesity1. Currently, bypass surgery using autologous vessels, allografts, and synthetic grafts are known as a commonly used for arterial substitutes2. However, these grafts have limited applications when an inner diameter of arteries is less than 6 mm due to low availability, thrombotic complications, compliance mismatch, and late intimal hyperplasia3,4. To overcome these limitations, tissue engineering has been successfully applied as a promising alternative to develop small-diameter arterial constructs that are nonthrombogenic, robust, and compliant. Several previous studies have developed small-diameter arterial constructs with tri-lamellar structure, excellent mechanical properties and burst pressure comparable to native arteries5,6. While high tensile strength and burst pressure by increasing collagen production from a rigid material or cell sheet scaffold, these constructs still had low elastin production and compliance, which is a major problem to cause graft failure after implantation. Considering these issues, we hypothesized that an elastometric biomaterial combined with mechanical conditioning would provide elasticity and conduct mechanical signals more efficiently to vascular cells, which increase extracellular matrix production and support cellular orientation.
The objective of this report is to introduce a fabrication technique of porous tubular scaffolds and a dynamic mechanical conditioning for applying them to arterial tissue engineering. We used a biodegradable elastomer, poly (glycerol sebacate) (PGS)7 for fabricating porous tubular scaffolds from the salt fusion method. Adult primary baboon smooth muscle cells (SMCs) were seeded on the lumen of scaffolds, which cultured in our designed pulsatile flow bioreactor for 3 weeks. PGS scaffolds had consistent thickness and randomly distributed macro- and micro-pores. Mechanical conditioning from pulsatile flow bioreactor supported SMC orientation and enhanced ECM production in scaffolds. These results suggest that elastomeric scaffolds and mechanical conditioning of bioreactor culture may be a promising method for arterial tissue engineering.

Elastomeric PGS scaffolds with vascular smooth muscle cells cultured in a pulsatile flow bioreactor may lead to promising small-diameter arterial constructs with native ECM production in a relatively short culture period.

PGS elastomérico Andaimes em Engenharia de Tecidos Arterial

Cardiovascular disease is one of the leading cause of mortality in the US and especially, coronary artery disease increases with an aging population and ...

Tissue Engineering of the Intestine in a Murine Model

Tissue-engineered small intestine (TESI) has successfully been used to rescue Lewis rats after massive small bowel resection, resulting in return to preoperative weights within 40 days.1 In humans, massive small bowel resection can result in short bowel syndrome, a functional malabsorptive state that confers significant morbidity, mortality, and healthcare costs including parenteral nutrition dependence, liver failure and cirrhosis, and the need for multivisceral organ transplantation.2 In this paper, we describe and document our protocol for creating tissue-engineered intestine in a mouse model with a multicellular organoid units-on-scaffold approach. Organoid units are multicellular aggregates derived from the intestine that contain both mucosal and mesenchymal elements,3 the relationship between which preserves the intestinal stem cell niche.4 In ongoing and future research, the transition of our technique into the mouse will allow for investigation of the processes involved during TESI formation by utilizing the transgenic tools available in this species.5The availability of immunocompromised mouse strains will also permit us to apply the technique to human intestinal tissue and optimize the formation of human TESI as a mouse xenograft before its transition into humans. Our method employs good manufacturing practice (GMP) reagents and materials that have already been approved for use in human patients, and therefore offers a significant advantage over approaches that rely upon decellularized animal tissues. The ultimate goal of this method is its translation to humans as a regenerative medicine therapeutic strategy for short bowel syndrome.

This article and the accompanying video present our protocol for generating tissue-engineered intestine in the mouse, using an organoid units-on-scaffold approach.

Engenharia de Tecidos do Intestino num modelo murino

Tissue-engineered small intestine (TESI) has successfully been used to rescue Lewis rats after massive small bowel resection, resulting in return to ...

Capillary Force Lithography for Cardiac Tissue Engineering

Cardiovascular disease remains the leading cause of death worldwide1. Cardiac tissue engineering holds much promise to deliver groundbreaking medical discoveries with the aims of developing functional tissues for cardiac regeneration as well as in vitro screening assays. However, the ability to create high-fidelity models of heart tissue has proven difficult. The heart&#8217;s extracellular matrix (ECM) is a complex structure consisting of both biochemical and biomechanical signals ranging from the micro- to the nanometer scale2. Local mechanical loading conditions and cell-ECM interactions have recently been recognized as vital components in cardiac tissue engineering3-5.
A large portion of the cardiac ECM is composed of aligned collagen fibers with nano-scale diameters that significantly influences tissue architecture and electromechanical coupling2. Unfortunately, few methods have been able to mimic the organization of ECM fibers down to the nanometer scale. Recent advancements in nanofabrication techniques, however, have enabled the design and fabrication of scalable scaffolds that mimic the in vivo structural and substrate stiffness cues of the ECM in the heart6-9.
Here we present the development of two reproducible, cost-effective, and scalable nanopatterning processes for the functional alignment of cardiac cells using the biocompatible polymer poly(lactide-co-glycolide) (PLGA)8 and a polyurethane (PU) based polymer. These anisotropically nanofabricated substrata (ANFS) mimic the underlying ECM of well-organized, aligned tissues and can be used to investigate the role of nanotopography on cell morphology and function10-14.
Using a nanopatterned (NP) silicon master as a template, a polyurethane acrylate (PUA) mold is fabricated. This PUA mold is then used to pattern the PU or PLGA hydrogel via UV-assisted or solvent-mediated capillary force lithography (CFL), respectively15,16. Briefly, PU or PLGA pre-polymer is drop dispensed onto a glass coverslip and the PUA mold is placed on top. For UV-assisted CFL, the PU is then exposed to UV radiation (&#955; = 250-400 nm) for curing. For solvent-mediated CFL, the PLGA is embossed using heat (120 &#176;C) and pressure (100 kPa). After curing, the PUA mold is peeled off, leaving behind an ANFS for cell culture. Primary cells, such as neonatal rat ventricular myocytes, as well as human pluripotent stem cell-derived cardiomyocytes, can be maintained on the ANFS2.

In this protocol, we demonstrate the fabrication of biomimetic cardiac cell culture substrata made from two distinct polymeric materials using capillary force lithography. The described methods provide a scalable, cost-effective technique to engineer the structure and function of macroscopic cardiac tissues for in vitro and in vivo applications.

Capilar Força Litografia de Engenharia tecido cardíaco

Cardiovascular disease remains the leading cause of death worldwide1. Cardiac tissue engineering holds much promise to deliver groundbreaking medical ...

Tissue Engineering of a Human 3D in vitro Tumor Test System

Cancer is one of the leading causes of death worldwide. Current therapeutic strategies are predominantly developed in 2D culture systems, which inadequately reflect physiological conditions in vivo. Biological 3D matrices provide cells an environment in which cells can self-organize, allowing the study of tissue organization and cell differentiation. Such scaffolds can be seeded with a mixture of different cell types to study direct 3D cell-cell-interactions. To mimic the 3D complexity of cancer tumors, our group has developed a 3D in vitro tumor test system.	
	Our 3D tissue test system models the in vivo situation of malignant peripheral nerve sheath tumors (MPNSTs), which we established with our decellularized porcine jejunal segment derived biological vascularized scaffold (BioVaSc). In our model, we reseeded a modified BioVaSc matrix with primary fibroblasts, microvascular endothelial cells (mvECs) and the S462 tumor cell line. For static culture, the vascular structure of the BioVaSc is removed and the remaining scaffold is cut open on one side (Small Intestinal Submucosa SIS-Muc). The resulting matrix is then fixed between two metal rings (cell crowns).	
	Another option is to culture the cell-seeded SIS-Muc in a flow bioreactor system that exposes the cells to shear stress. Here, the bioreactor is connected to a peristaltic pump in a self-constructed incubator. A computer regulates the arterial oxygen and nutrient supply via parameters such as blood pressure, temperature, and flow rate. This setup allows for a dynamic culture with either pressure-regulated pulsatile or constant flow.	
	In this study, we could successfully establish both a static and dynamic 3D culture system for MPNSTs. The ability to model cancer tumors in a more natural 3D environment will enable the discovery, testing, and validation of future pharmaceuticals in a human-like model.

Tissue Engineering of a Human 3D in vitro Tumor Test System

Methods to create human 3D tumor tissues as test systems are described. These technologies are based on a decellularized Biological Vascularized Scaffold (BioVaSc), primary human cells and a tumor cell line, which can be cultured under static as well as under dynamic conditions in a flow bioreactor.

Engenharia de Tecidos de um 3D Humano<em&gt; In vitro</em&gt; Sistema de Teste de Tumor

Cancer is one of the leading causes of death worldwide.  Current therapeutic strategies are predominantly developed in 2D culture  systems, which ...

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.

Geração de espessura completa tridimensional Pele Equivalente 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 ...

Engineering 3D Cellularized Collagen Gels for Vascular Tissue Regeneration

Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. Collagen has been extensively used for a wide range of biomedical applications and is considered a valid alternative to synthetic materials due to its inherent biocompatibility (i.e., low antigenicity, inflammation, and cytotoxic responses). However, the limited mechanical properties and the related low hand-ability of collagen gels have hampered their use as scaffold materials for vascular tissue engineering. Therefore, the rationale behind this work was first to engineer cellularized collagen gels into a tubular-shaped geometry and second to enhance smooth muscle cells driven reorganization of collagen matrix to obtain tissues stiff enough to be handled.
The strategy described here is based on the direct assembling of collagen and smooth muscle cells (construct) in a 3D cylindrical geometry with the use of a molding technique. This process requires a maturation period, during which the constructs are cultured in a bioreactor under static conditions (without applied external dynamic mechanical constraints) for 1 or 2 weeks. The &#8220;static bioreactor&#8221; provides a monitored and controlled sterile environment (pH, temperature, gas exchange, nutrient supply and waste removal) to the constructs. During culture period, thickness measurements were performed to evaluate the cells-driven remodeling of the collagen matrix, and glucose consumption and lactate production rates were measured to monitor the cells metabolic activity. Finally, mechanical and viscoelastic properties were assessed for the resulting tubular constructs. To this end, specific protocols and a focused know-how (manipulation, gripping, working in hydrated environment, and so on) were developed to characterize the engineered tissues.

In this work, we present a technique for the rapid fabrication of living vascular tissues by direct culturing of collagen, smooth muscle cells and endothelial cells. In addition, a new protocol for the mechanical characterization of engineered vascular tissues is described.

Engenharia 3D celularizados Colágeno Gel para Vascular Regeneração Tecidual

Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. ...

Sandwich-like Microenvironments to Harness Cell/Material Interactions

Cell culture has been traditionally carried out on bi-dimensional (2D) substrates where cells adhere using ventral receptors to the biomaterial surface. However in vivo, most of the cells are completely surrounded by the extracellular matrix (ECM), resulting in a three-dimensional (3D) distribution of receptors. This may trigger differences in the outside-in signaling pathways and thus in cell behavior.
This article shows that stimulating the dorsal receptors of cells already adhered to a 2D substrate by overlaying a film of a new material (a sandwich-like culture) triggers important changes with respect to standard 2D cultures. Furthermore, the simultaneous excitation of ventral and dorsal receptors shifts cell behavior closer to that found in 3D environments. Additionally, due to the nature of the system, a sandwich-like culture is a versatile tool that allows the study of different parameters in cell/material interactions, e.g., topography, stiffness and different protein coatings at both the ventral and dorsal sides. Finally, since sandwich-like cultures are based on 2D substrates, several analysis procedures already developed for standard 2D cultures can be used normally, overcoming more complex procedures needed for 3D systems.

The following protocol describes the procedure to assemble sandwich-like cultures to be used as an intermediate stage between bi-dimensional (2D) and three-dimensional (3D) cellular environments. The engineered systems can have applications in microscopy, biomechanics, biochemistry and cell biology assays.

Microambientes sanduíche-como aproveitarar Telemóveis / interações materiais

Cell culture has been traditionally carried out on bi-dimensional (2D) substrates where cells adhere using ventral receptors to the biomaterial surface. ...

Preparation of Thermoresponsive Nanostructured Surfaces for Tissue Engineering

Thermoresponsive poly(N-isopropylacrylamide) (PIPAAm)-immobilized surfaces for controlling cell adhesion and detachment were fabricated by the Langmuir-Schaefer method. Amphiphilic block copolymers composed of polystyrene and PIPAAm (St-IPAAms) were synthesized by reversible addition-fragmentation chain transfer (RAFT) radical polymerization. A chloroform solution of St-IPAAm molecules was gently dropped into a Langmuir-trough apparatus, and both barriers of the apparatus were moved horizontally to compress the film to regulate its density. Then, the St-IPAAm Langmuir film was horizontally transferred onto a hydrophobically modified glass substrate by a surface-fixed device. Atomic force microscopy images clearly revealed nanoscale sea-island structures on the surface. The strength, rate, and quality of cell adhesion and detachment on the prepared surface were modulated by changes in temperature across the lower critical solution temperature range of PIPAAm molecules. In addition, a two-dimensional cell structure (cell sheet) was successfully recovered on the optimized surfaces. These unique PIPAAm surfaces may be useful for controlling the strength of cell adhesion and detachment.

Nanoscaled sea-island surfaces composed of thermoresponsive block copolymers were fabricated by the Langmuir-Schaefer method for controlling spontaneous cell adhesion and detachment. Both the preparation of the surface and the adhesion and detachment of cells on the surface were visualized.

Preparação de Thermoresponsive nanoestruturados Surfaces para Engenharia de Tecidos

Thermoresponsive poly(N-isopropylacrylamide) (PIPAAm)-immobilized surfaces for controlling cell adhesion and detachment were fabricated by the ...

Isolation of Murine Adipose Tissue-derived Microvascular Fragments as Vascularization Units for Tissue Engineering

A functional microvascular network is of pivotal importance for the survival and integration of engineered tissue constructs. For this purpose, several angiogenic and prevascularization strategies have been established. However, most cell-based approaches include time-consuming in vitro steps for the formation of a microvascular network. Hence, they are not suitable for intraoperative one-step procedures. Adipose tissue-derived microvascular fragments (ad-MVF) represent promising vascularization units. They can be easily isolated from fat tissue and exhibit a functional microvessel morphology. Moreover, they rapidly reassemble into new microvascular networks after in vivo implantation. In addition, ad-MVF have been shown to induce lymphangiogenesis. Finally, they are a rich source of mesenchymal stem cells, which may further contribute to their high vascularization potential. In previous studies we have demonstrated the remarkable vascularization capacity of ad-MVF in engineered bone and skin substitutes. In the present study, we report on a standardized protocol for the enzymatic isolation of ad-MVF from murine fat tissue.

We present a protocol to isolate adipose tissue-derived microvascular fragments that represent promising vascularization units. They can be rapidly isolated, do not require in vitro processing and, thus, may be used for one-step prevascularization in different fields of tissue engineering.

Isolamento de Murino adiposo derivada de tecido microvascular Fragmentos como Vascularização Unidades para engenharia de tecidos

A functional microvascular network is of pivotal importance for the survival and integration of engineered tissue constructs. For this purpose, several ...