Os autores agradecem Ruth Zelkha, MS, por sua assistência generosa em imagem. Esta pesquisa foi apoiada pelo Programa de Clínica de Desenvolvimento Scientist Award K12EY021475 para mim, conceder R01 EY024349-01A1 a ARD, EY01792 concessão núcleo do National Eye Institute, NIH, e um donativo incondicional da Pesquisa para prevenir a cegueira. ARD é o destinatário de um Prémio Carreira de Desenvolvimento de Pesquisa para prevenir a cegueira.

Todos os procedimentos realizados em animais em conformidade com a Associação de Pesquisa em Visão e Oftalmologia declarações para o uso de animais em pesquisa visão. Quatorze quatro a 6J de seis meses de idade, macho / fêmea C57BL / tipo selvagem foram utilizados: dez ratos para o modelo de lesão e quatro como animais de controlo (córneas sem ferimentos). 1. Preparação de animais <ol><li> Anestesiar um rato com uma injecção intraperitoneal de 100 mg / kg de cetamina e 5 mg / kg de mistura de xilazina. Após a anestesia começou a produzir efeitos, apertar o dedo do pé para confirmar a profundidade da anestesia; o animal não deve reagir. </li><li> Inspecione o olho sob uma lâmpada de fenda antes de realizar os experimentos para verificar a ausência de qualquer lesão da córnea anterior. </li><li> Instilar uma gota de cloridrato de tetracaína a 1% para o olho. Depois de 60-90 segundos, teste do reflexo corneal para confirmar a ausência de sensação. Anestalcon 0,5% pode ser usado em seu lugar. </li><li> Quando a perda de sensibilidade da córnea édeterminado, suavemente colocar uma gota de 5% de povidona-iodo no olho e no cabelo em torno do olho. Limpe a queda após 1 min ou espalhá-lo sobre o cabelo ao redor do olho para evitar que o cabelo de interferir com a ponta da ferramenta. </li></ol> 2. Equipamento abrasivo do epitélio corneano <ol><li> Usar luvas cirúrgicas e um vestido. Prepare as ferramentas necessárias: uma rebarba rotativa estéril e um par de pinças estéreis. Para um melhor controle, use uma pinça dobrados. Coloque as ferramentas em uma folha esterilizada durante o procedimento. </li><li> Usando a pinça dobrados, estabilizar o olho, agarrando as tampas do lado nasal e gentilmente proptosing o olho. Evitar o uso de muita pressão. </li><li> Sob um microscópio cirúrgico, fazer a barba 360 ° ao redor da área de limbo duas vezes utilizando a broca rotativa estéril. Vá ao redor do limbo com uma velocidade de 5-6 segundos por rodada. NOTA: A broca tem uma velocidade fixa. No entanto, para que o mesmo rode à velocidade estabelecida, a &quot;porca final&quot; deve ser completamente apertados. </li><li> Remover todo o epitélio corneano do limbo a limbo com a rebarba giratória. Para melhores resultados, mover a ferramenta de forma circular e prendê-lo de alguma forma paralela à superfície da córnea para trabalhar com a face lateral da ponta da mesma. Tome cuidado para não ferir o estroma por não re-escovar as áreas onde o epitélio já foi removido. Não aplique pressão sobre o olho. Limpe a ponta do pincel conforme necessário. </li><li> Instilar uma gota de tampão fosfato estéril sobre a córnea e limpe as folhas epiteliais isolada com um tecido de limpeza macio. </li><li> Raspar o epitélio remanescente, se alguma. </li><li> Preste atenção para a cauda do rato durante a cirurgia. NOTA: Se ocorrer qualquer movimento, a profundidade da anestesia se desvaneceu e mais injeção é necessária. Um terço a dois terços do volume injectado primária deve ser suficiente. Não overdose do animal com a medicação anestésica. </li><li> Esterilizar todas as ferramentas antes de usá-los em outro olho. </li></ol> 3. Confirmar remoção epitelial completa <ol><li> Aplicar uma gota de 1 mg / ml de fluoresceína de sódio sobre a córnea. Limpe a córnea após 30 seg e examiná-lo sob um microscópio com um filtro azul cobalto para verificar a completa remoção do epitélio. NOTA: As áreas de córnea com defeitos epiteliais são visualizados em verde. </li></ol> 4. Pós-operação Cuidados <ol><li> Coloque o animal em um cobertor de aquecimento e mantê-lo em um lugar seguro (por exemplo, em sua gaiola), enquanto em recuperação. Não manter um animal inconsciente na companhia de os conscientes. </li><li> Aplicar uma pomada oftálmica% eritromicina. Isso também irá prevenir o ressecamento dos olhos. Continuar a aplicação da diária de antibiótico por uma semana. </li><li> Injectar 0,1 mg / kg de buprenorfina por via subcutânea, após o procedimento e novamente após 12 horas. Continuar a injecção duas vezes por dia durante dois dias. </li><li> Observar o animal durante 30 - 45 min, até a recuperação completa da anestesia. NOTA: Movimento suave dos músculos respiratórios na superfície ventral indica bem-estar animal enquanto em recuperação. </li></ol>

<ol>
	<li>Afsharkhamseh, N., 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=Stability+of+limbal+stem+cell+deficiency+after+mechanical+and+thermal+injuries+in+mice.">Stability of limbal stem cell deficiency after mechanical and thermal injuries in mice.</a> Exp. Eye Res. 145, 88-92 (2015).</li><li>Dor&#224;, N. J., Hill, R. E., Collinson, J. M., West, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lineage+tracing+in+the+adult+mouse+corneal+epithelium+supports+the+limbal+epithelial+stem+cell+hypothesis+with+intermittent+periods+of+stem+cell+quiescence.">Lineage tracing in the adult mouse corneal epithelium supports the limbal epithelial stem cell hypothesis with intermittent periods of stem cell quiescence.</a> Stem Cell Res. 15 (3), 665-677 (2015).</li><li>Ahmad, S., Osei-Bempong, C., Dana, R., Jurkunas, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+culture+and+transplantation+of+human+limbal+stem+cells.">The culture and transplantation of human limbal stem cells.</a> J. Cell Physiol. 225 (1), 15-19 (2010).</li><li>Kolli, S., Ahmad, S., Lako, M., Figueiredo, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Successful+clinical+implementation+of+corneal+epithelial+stem+cell+therapy+for+treatment+of+unilateral+limbal+stem+cell+deficiency.">Successful clinical implementation of corneal epithelial stem cell therapy for treatment of unilateral limbal stem cell deficiency.</a> Stem Cells. 28 (3), 597-610 (2010).</li><li>Ahmad, S., Figueiredo, F., Lako, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corneal+epithelial+stem+cells:+characterization,+culture+and+transplantation.">Corneal epithelial stem cells: characterization, culture and transplantation.</a> Regen. Med. 1 (1), 29-44 (2006).</li><li>He, H., Yiu, 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=Stem+cell-based+therapy+for+treating+limbal+stem+cells+deficiency:+A+review+of+different+strategies.">Stem cell-based therapy for treating limbal stem cells deficiency: A review of different strategies.</a> Saudi J. Ophthalmol. 28 (3), 188-194 (2014).</li><li>Pal-Ghosh, S., Pajoohesh-Ganji, A., Tadvalkar, G., Stepp, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Removal+of+the+basement+membrane+enhances+corneal+wound+healing.">Removal of the basement membrane enhances corneal wound healing.</a> Exp Eye Res. 93 (6), 927-936 (2011).</li><li>Stepp, M. A., 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=Wounding+the+cornea+to+learn+how+it+heals.">Wounding the cornea to learn how it heals.</a> Exp. Eye Res. 121, 178-193 (2014).</li><li>Amirjamshidi, 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=Limbal+fibroblast+conditioned+media:+a+non-invasive+treatment+for+limbal+stem+cell+deficiency.">Limbal fibroblast conditioned media: a non-invasive treatment for limbal stem cell deficiency.</a> Mol. Vis. 17, 658-666 (2011).</li><li>Li, F. 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=Evaluation+of+the+AlgerBrush+II+rotating+burr+as+a+tool+for+inducing+ocular+surface+failure+in+the+New+Zealand+White+rabbit.">Evaluation of the AlgerBrush II rotating burr as a tool for inducing ocular surface failure in the New Zealand White rabbit.</a> Exp. Eye Res. 147, 1-11 (2016).</li><li>Ti, S. E., Anderson, D., Touhami, A., Kim, C., Tseng, S. C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+affecting+outcome+following+transplantation+of+ex+vivo+expanded+limbal+epithelium+on+amniotic+membrane+for+total+limbal+deficiency+in+rabbits.">Factors affecting outcome following transplantation of ex vivo expanded limbal epithelium on amniotic membrane for total limbal deficiency in rabbits.</a> Invest. Ophthalmol. Vis. Sci. 43 (8), 2584-2592 (2002).</li><li>Ma, 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=Reconstruction+of+chemically+burned+rat+corneal+surface+by+bone+marrow-derived+human+mesenchymal+stem+cells.">Reconstruction of chemically burned rat corneal surface by bone marrow-derived human mesenchymal stem cells.</a> Stem Cells. 24 (2), 315-321 (2006).</li><li>Bu, P., 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=Effects+of+activated+omental+cells+on+rat+limbal+corneal+alkali+injury.">Effects of activated omental cells on rat limbal corneal alkali injury.</a> Exp. Eye Res. 121, 143-146 (2014).</li><li>Luengo Gimeno, F., Lavigne, V., Gatto, S., Croxatto, J. O., Correa, L., Gallo, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advances+in+corneal+stem-cell+transplantation+in+rabbits+with+severe+ocular+alkali+burns.">Advances in corneal stem-cell transplantation in rabbits with severe ocular alkali burns.</a> J. Cataract Refract. Surg. 33 (11), 1958-1965 (2007).</li><li>Lin, Z., 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=A+mouse+model+of+limbal+stem+cell+deficiency+induced+by+topical+medication+with+the+preservative+benzalkonium+chloride.">A mouse model of limbal stem cell deficiency induced by topical medication with the preservative benzalkonium chloride.</a> Invest. Ophthalmol. Vis. Sci. 54 (9), 6314-6325 (2013).</li><li>Huang, A. J., Tseng, 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=Corneal+epithelial+wound+healing+in+the+absence+of+limbal+epithelium.">Corneal epithelial wound healing in the absence of limbal epithelium.</a> Invest. Ophthalmol. Vis. Sci. 32 (1), 96-105 (1991).</li><li>Liu, C. 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=Cornea-specific+expression+of+K12+keratin+during+mouse+development.">Cornea-specific expression of K12 keratin during mouse development.</a> Curr. Eye Res. 12 (11), 963-974 (1993).</li><li>Nakatsu, M. N., Gonz&#225;lez, S., Mei, H., Deng, S. X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+limbal+mesenchymal+cells+support+the+growth+of+human+corneal+epithelial+stem/progenitor+cells.">Human limbal mesenchymal cells support the growth of human corneal epithelial stem/progenitor cells.</a> Invest. Ophthalmol. Vis. Sci. 55 (10), 6953-6959 (2014).</li><li>Pajoohesh-Ganji, A., Pal-Ghosh, S., Tadvalkar, G., Stepp, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corneal+goblet+cells+and+their+niche:+implications+for+corneal+stem+cell+deficiency.">Corneal goblet cells and their niche: implications for corneal stem cell deficiency.</a> Stem Cells. 30 (9), 2032-2043 (2012).</li><li>McCloy, R. A., Rogers, S., Caldon, C. E., Lorca, T., Castro, A., Burgess, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Partial+inhibition+of+Cdk1+in+G+2+phase+overrides+the+SAC+and+decouples+mitotic+events.">Partial inhibition of Cdk1 in G 2 phase overrides the SAC and decouples mitotic events.</a> Cell Cycle. 13, 1400-1412 (2014).</li></ol>

The authors declare that they have nothing to disclose.

Este artigo descreve uma técnica reproduzível e relativamente simples para criar um modelo de mouse LSCD. Há vários aspectos importantes deste modelo que são dignos de nota. Em primeiro lugar, ao contrário dos modelos que usam produtos químicos 11, 12, a lesão envolve primariamente o epitélio de superfície (e membrana basal), com danos mínimos para o estroma corneano subjacente ou para outras estruturas intra-oculares. Assim, existe apenas a inflamação limitada e cicatrizes, ambos os quais podem ...

O epitélio corneano é necessária para manter a clareza ea integridade da córnea. É constantemente renovada ao longo da vida através das células estaminais epiteliais que residem no limbo-uma zona estreita na junção da córnea e da conjuntiva. Estas células estaminais do limbo auto-renovação desempenham um papel crucial na regeneração do epitélio da córnea, tanto normalmente e após a lesão. esgotamento parcial ou total destas células estaminais irão resultar em erosões corneanas recorrentes, dor, cicatrização da córnea e neovascularização, a aparência das células caliciformes, e, se deixados sem tratamento cegueira, da córnea. Esta condição é conhecida como deficiência límbica (LSCD) e pode ser idiopática; hereditária; ou adquirida devido a lesões químicas ou térmicas, lentes de contacto prolongado desgaste, e inflamação crônica 1-6. Investigação sobre LSCD exige um modelo animal adequado que não imita apenas a doença em seres humanos, mas é reprodutível e sustentável, com o mínimo ummontagem de prejuízo para outras estruturas da córnea e oculares. Este modelo é necessário avaliar tratamentos e esclarecer os mecanismos da doença em níveis moleculares e celulares. Tal como descrito antes 1, com a utilização de uma broca rotativa, pode-se facilmente desenvolver um modelo de ratinho de LSCD que apresenta as vantagens acima mencionadas e persiste durante pelo menos três meses. O objetivo deste estudo é apresentar um modelo simples, reprodutível e sustentável do rato de LSCD. A broca rotativa é uma ferramenta útil que remove uniformemente o epitélio sem ferir o estroma subjacente 1. Ele tem sido usado para induzir a erosão da córnea central 7, 8 em estudos de cicatrização de feridas. A técnica apresentada, ora para criar LSCD em um mouse não tem sido relatada antes. Anteriormente introduzidos métodos de raspagem do epitélio com um resultado espátula romba num menos uniforme lesão, particularmente no limbo e um fenótipo mais variável 1, 9, com mais restauração óepitélio normal da córnea f 1. Ao contrário do raspador sem corte, a broca rotativa elimina a membrana basal epitelial bem como 7, 8, 10. Outros métodos descritos para separar as células estaminais envolvem a utilização de produtos químicos, tais como hidróxido de sódio, n-heptanol, e cloreto de benzalcónio, o que não só pode induzir lesão indesejada para estruturas oculares subjacentes, mas também pode levar a inflamação significativa e subsequente opacificação da córnea ou metaplasia escamosa epitelial 11-15. A rebarba de rotação não está associado a estas complicações graves. A remoção cirúrgica do epitélio do limbo, sozinho ou com o uso de produtos químicos 10, 11, 16, é mais difícil de realizar e não é a melhor opção em animais com pequenas olhos e um epitélio do limbo fina (como ratos). Além disso, surpreendentemente, limbectomy pode ainda deixar algum do epitélio do limbo para trás 10. A técnica descrita abaixo irá resultar em LSCD com uma neovascularizaçãod conjuntivalização que imita a apresentação de LSCD completa em pacientes e tem a duração de pelo menos três meses 1. É apropriado para aqueles que pretendem estudar LSCD ou fisiopatologia cicatrização de feridas, imunologia e potenciais tratamentos em ratinhos. Possivelmente, com algumas modificações, este procedimento pode ser realizado em ratos ou coelhos 10. À medida que a rebarba rotativo remove eficientemente o epitélio, ele pode ser utilizado em qualquer pesquisa relativos à abrasão da córnea epitelial / ferimento e em qualquer tratamento relacionada ou estudos de biologia molecular.

<table border="0" cellpadding="0" cellspacing="0" width="1091">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:320px;">&#160;Rotating burr: AlgerBrush II rust ring remover&#160;</td>
			<td style="width:277px;">Rumex International Co, Clearwater, FL</td>
			<td style="width:144px;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; 16-141</td>
			<td style="width:351px;">0.5 mm burr. Also available from other companies.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:320px;">&#160;Surgical microscope</td>
			<td style="width:277px;">Wild Heerbrugg, Switzerland</td>
			<td style="width:144px;">&#160;&#160;&#160;&#160;&#160;&#160; Wild M691</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:320px;">&#160;Digital camera</td>
			<td style="width:277px;">Nikon, Thailand</td>
			<td style="width:144px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:320px;">&#160;Nikon FS-2 slit lamp</td>
			<td style="width:277px;">Nikon, Japan</td>
			<td style="width:144px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:320px;">&#160;Polyclonal anti-CK12 antibody</td>
			<td style="width:277px;">Santa Cruz Blotechnology, CA,</td>
			<td style="width:144px;">&#160;&#160;&#160;&#160;&#160;&#160;&#160; SC-17101</td>
			<td>1:100 concentration</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:320px;">&#160;Monoclonal anti-CK8 antibody</td>
			<td style="width:277px;">TROMA-I-s, Iowa City, IA</td>
			<td style="width:144px;">&#160;&#160;&#160;&#160;&#160;&#160;&#160; AB_531826</td>
			<td>1:50 concentration</td>
		</tr>
	</tbody>
</table>

a simple mechanical procedure to create limbal stem cell deficiency in mouse

deficiência límbica (LSCD) é um estado de mau funcionamento ou perda de células-tronco epiteliais do limbo, após o qual o epitélio corneano é substituído por conjuntiva. Os pacientes sofrem de defeitos da córnea recorrentes, dor, inflamação, e perda de visão. Anteriormente, foi descrito um modelo de murídeo de LSCD e comparado com dois outros modelos. O objetivo era produzir um modelo de rato consistente de LSCD que ambos os imita o fenótipo em humanos e dura o tempo suficiente para torná-lo possível estudar a fisiopatologia da doença e avaliar novos tratamentos. Aqui, a técnica é descrita em mais detalhe. Uma ferramenta motorizada com uma broca rotativa foi concebida para remover os anéis de ferrugem a partir da superfície da córnea ou para suavizar a cama pterígio em pacientes. É um dispositivo adequado para criar o modelo LSCD desejado. É um fácil de usar ferramenta prontamente disponível, com uma ponta fina que torna apropriado para trabalhar em pequenos olhos, comoem ratinhos. A sua aplicação impede traumas desnecessários ao olho e que não resultam em lesões indesejadas, como é frequentemente o caso com os modelos de lesão química. Ao contrário de um raspador romba, que remove o epitélio com a membrana basal. Neste protocolo, a área límbica foi desgastada duas vezes, e então todo o epitélio corneano foi raspada do limbo a limbo. Para evitar lesões estroma, o cuidado foi tomado para não escovar a superfície da córnea uma vez que o epitélio já foi removido.

Dentro de um mês após a realização desta técnica, 100% das córneas desenvolveram neovascularização superficial (Figura 1A. As fotos foram tiradas com uma câmera conectada a uma lâmpada de fenda sob um campo brilhante e filtro azul cobalto). Em 18/20 (90%) dos olhos, neovascularização envolvida a totalidade da superfície da córnea (Figura 1A). Em 2/20 (10%), a neovascularização foi observada em três dos quatro quadrantes da córnea, mas a...

Watch this Scientific Journal Video about A Simple Mechanical Procedure to Create Limbal Stem Cell Deficiency in Mouse at JoVE.com

A Simple Mechanical Procedure to Create Limbal Stem Cell Deficiency in Mouse

O seguinte artigo fornece uma técnica fácil, reprodutível para efetivamente criar um modelo do rato sustentável da deficiência límbica (LSCD). Este modelo animal é útil em testar e comparar a eficácia dos tratamentos para as doenças de células estaminais do limbo.

Um procedimento mecânico simples de criar Limbal Deficiência Stem Cell no mouse

Limbal stem cell deficiency (LSCD) is a state of malfunction or loss of limbal epithelial stem cells, after which the corneal epithelium is replaced with ...

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8.3K visualizações.  University of Illinois at Chicago.  O seguinte artigo fornece uma técnica fácil, reprodutível para efetivamente criar um modelo do rato sustentável da deficiência límbica (LSCD). Este modelo animal é útil em testar e comparar a eficácia dos tratamentos para as doenças de células estaminais do limbo. 

Vídeo: A Simple Mechanical Procedure to Create Limbal Stem Cell Deficiency in Mouse

A Mouse Model of in Utero Transplantation

The transplantation of stem cells and viruses in utero has tremendous potential for treating congenital disorders in the human fetus. For example, in utero transplantation (IUT) of hematopoietic stem cells has been used to successfully treat patients with severe combined immunodeficiency.1,2 In several other conditions, however, IUT has been attempted without success.3 Given these mixed results, the availability of an efficient non-human model to study the biological sequelae of stem cell transplantation and gene therapy is critical to advance this field. We and others have used the mouse model of IUT to study factors affecting successful engraftment of in utero transplanted hematopoietic stem cells in both wild-type mice4-7 and those with genetic diseases.8,9 The fetal environment also offers considerable advantages for the success of in utero gene therapy. For example, the delivery of adenoviral10, adeno-associated viral10, retroviral11, and lentiviral vectors12,13 into the fetus has resulted in the transduction of multiple organs distant from the site of injection with long-term gene expression. in utero gene therapy may therefore be considered as a possible treatment strategy for single gene disorders such as muscular dystrophy or cystic fibrosis. Another potential advantage of IUT is the ability to induce immune tolerance to a specific antigen. As seen in mice with hemophilia, the introduction of Factor IX early in development results in tolerance to this protein.14 
In addition to its use in investigating potential human therapies, the mouse model of IUT can be a powerful tool to study basic questions in developmental and stem cell biology. For example, one can deliver various small molecules to induce or inhibit specific gene expression at defined gestational stages and manipulate developmental pathways. The impact of these alterations can be assessed at various timepoints after the initial transplantation. Furthermore, one can transplant pluripotent or lineage specific progenitor cells into the fetal environment to study stem cell differentiation in a non-irradiated and unperturbed host environment.
The mouse model of IUT has already provided numerous insights within the fields of immunology, and developmental and stem cell biology. In this video-based protocol, we describe a step-by-step approach to performing IUT in mouse fetuses and outline the critical steps and potential pitfalls of this technique.

A Mouse Model of in Utero Transplantation

The mouse model of in utero transplantation is a versatile tool that can be used to study the potential clinical applications of stem cell transplantation and gene therapy in the fetus. In this protocol, we present a general approach to performing this technique

Um modelo do rato de No Utero Transplante

The transplantation of stem cells and viruses in utero has tremendous potential for treating congenital disorders in the human fetus.  For example, in ...

Medicina

Myo-mechanical Analysis of Isolated Skeletal Muscle

To assess the in vivo effects of therapeutic interventions for the treatment of muscle disease 1,2,3, quantitative methods are needed that measure force generation and fatigability in treated muscle. We describe a detailed approach to evaluating myo-mechanical properties in freshly explanted hindlimb muscle from the mouse. We describe the atraumatic harvest of mouse extensor digitorum longus muscle, mounting the muscle in a muscle strip myograph (Model 820MS; Danish Myo Technology), and the measurement of maximal twitch and tetanic tension, contraction time, and half-relaxation time, using a square pulse stimulator (Model S48; Grass Technologies). Using these measurements, we demonstrate the calculation of specific twitch and tetanic tension normalized to muscle cross-sectional area, the twitch-to-tetanic tension ratio, the force-frequency relationship curve and the low frequency fatigue curve 4. This analysis provides a method for quantitative comparison between therapeutic interventions in mouse models of muscle disease 1,2,3,5, as well as comparison of the effects of genetic modification on muscle function 6,7,8,9.

To assess the in vivo effects of therapeutic interventions for muscle disease, methods are needed to quantitate force generation and fatigability in treated muscle. We detail an approach to evaluating myo-mechanical properties in explanted mouse hindlimb muscle. This analysis provides a robust approach to quantitating the effects of genetic modification on muscle function, as well as comparison of therapies in mouse models of muscle disease.

Myo-mecânico Análise do músculo esquelético isolado

To assess the in vivo effects of therapeutic interventions for the treatment of muscle disease 1,2,3, quantitative methods are needed that measure force ...

A Simple Method of Mouse Lung Intubation

A simple procedure to intubate mice for pulmonary function measurements would have several advantages in longitudinal studies with limited numbers or expensive animal. One of the reasons that this is not done more routinely is that it is relatively difficult, despite there being several published studies that describe ways to achieve it. In this paper we demonstrate a procedure that eliminates one of the major hurdles associated with this intubation, that of visualizing the trachea during the entire time of intubation. The approach uses a 0.5 mm fiberoptic light source that serves as an introducer to direct the intubation cannula into the mouse trachea. We show that it is possible to use this procedure to measure lung mechanics in individual mice over a time course of at least several weeks. The technique can be set up with relatively little expense and expertise, and it can be routinely accomplished with relatively little training. This should make it possible for any laboratory to routinely carry out this intubation, thereby allowing longitudinal studies in individual mice, thereby minimizing the number of mice needed and increasing the statistical power by using each mouse as its own control.

This paper describes a striaghforward and efficient method of intubating mice for pulmonary function measurements or pulmonary instillation, that allows the mice to recover and be studied at later times. The procedure involves an inexpensive fiberoptic light source that directly illuminates the trachea.

Um método simples de intubação Lung Rato

A  simple procedure to intubate mice for pulmonary function measurements would  have several advantages in longitudinal studies with limited numbers or  ...

Parabiosis in Mice: A Detailed Protocol

Parabiosis is a surgical union of two organisms allowing sharing of the blood circulation. Attaching the skin of two animals promotes formation of microvasculature at the site of inflammation. Parabiotic partners share their circulating antigens and thus are free of adverse immune reaction. First described by Paul Bert in 18641, the parabiosis surgery was refined by Bunster and Meyer in 1933 to improve animal survival2. In the current protocol, two mice are surgically joined following a modification of the Bunster and Meyer technique. Animals are connected through the elbow and knee joints followed by attachment of the skin allowing firm support that prevents strain on the sutured skin. Herein, we describe in detail the parabiotic joining of a ubiquitous GFP expressing mouse to a wild type (WT) mouse. Two weeks after the procedure, the pair is separated and GFP positive cells can be detected by flow cytometric analysis in the blood circulation of the WT mouse. The blood chimerism allows one to examine the contribution of the circulating cells from one animal in the other.

Parabiotic joining of two organisms leads to the development of a shared circulatory system. In this protocol, we describe the surgical steps to form a parabiotic connection between a wild-type mouse and a constitutive GFP-expressing mouse.

Parabiose em Ratos: Um protocolo detalhado

Parabiosis is a surgical union of two organisms allowing sharing of the blood circulation. Attaching the skin of two animals promotes formation of ...

A Surgical Procedure for Resecting the Mouse Rib: A Model for Large-Scale Long Bone Repair

This protocol introduces researchers to a new model for large-scale bone repair utilizing the mouse rib. The procedure details the following: preparation of the animal for surgery, opening the thoracic body wall, exposing the desired rib from the surrounding intercostal muscles, excising the desired section of rib without inducing a pneumothorax, and closing the incisions. Compared to the bones of the appendicular skeleton, the ribs are highly accessible. In addition, no internal or external fixator is necessary since the adjacent ribs provide a natural fixation. The surgery uses commercially available supplies, is straightforward to learn, and well-tolerated by the animal. The procedure can be carried out with or without removing the surrounding periosteum, and therefore the contribution of the periosteum to repair can be assessed. Results indicate that if the periosteum is retained, robust repair occurs in 1 - 2 months. We expect that use of this protocol will stimulate research into rib repair and that the findings will facilitate the development of new ways to stimulate bone repair in other locations around the body.

The overall goal of this procedure is to successfully resect a portion of bone from the rib of a mouse. The procedure was developed as a model to study large-scale long bone repair.

Um procedimento cirúrgico para ressecção do mouse Rib: Um Modelo de Grande Escala Repair longo osso

This protocol introduces researchers to a new model for large-scale bone repair utilizing the mouse rib. The procedure details the following: preparation ...

Studying Pancreatic Cancer Stem Cell Characteristics for Developing New Treatment Strategies

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor initiation, metastasis and resistance to radio- and chemotherapy. Here we describe a specific methodology for culturing primary human pancreatic CSCs as tumor spheres in anchorage-independent conditions. Cells are grown in serum-free, non-adherent conditions in order to enrich for CSCs while their more differentiated progenies do not survive and proliferate during the initial phase following seeding of single cells. This assay can be used to estimate the percentage of CSCs present in a population of tumor cells. Both size (which can range from 35 to 250 micrometers) and number of tumor spheres formed represents CSC activity harbored in either bulk populations of cultured cancer cells or freshly harvested and digested tumors 1,2. Using this assay, we recently found that metformin selectively ablates pancreatic CSCs; a finding that was subsequently further corroborated by demonstrating diminished expression of pluripotency-associated genes/surface markers and reduced in vivo tumorigenicity of metformin-treated cells. As the final step for preclinical development we treated mice bearing established tumors with metformin and found significantly prolonged survival. Clinical studies testing the use of metformin in patients with PDAC are currently underway (e.g., NCT01210911, NCT01167738, and NCT01488552). Mechanistically, we found that metformin induces a fatal energy crisis in CSCs by enhancing reactive oxygen species (ROS) production and reducing mitochondrial transmembrane potential. In contrast, non-CSCs were not eliminated by metformin treatment, but rather underwent reversible cell cycle arrest. Therefore, our study serves as a successful example for the potential of in vitro sphere formation as a screening tool to identify compounds that potentially target CSCs, but this technique will require further in vitro and in vivo validation to eliminate false discoveries.

Pancreatic cancer stem cells (CSCs) can be expanded in vitro using the anchorage-independent sphere culture technique, which represents a powerful tool to study CSC biology and can serve as the first step to develop novel CSC-targeting therapies. Here the methodology for expanding, analyzing and targeting of pancreatic CSCs is provided.

Estudar o cancro do pâncreas Stem características celulares para desenvolver estratégias Novo tratamento

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor ...

A Simple Device to Rapidly Prepare Whole Mounts of the Mouse Intestine

Preparing whole mounts of the mouse small intestine and colon for subsequent analysis or quantification can be time consuming and difficult. We describe the use of a simple device to cut and &#8216;roll&#8217; mouse intestines to rapidly prepare whole mount preparations of superior and uniform quality to that which can be achieved by hand. The device comprises a base that holds 4 stainless steel rods and a top, which acts a cutting guide. The rods are inserted into the lumen of the small intestine [divided into thirds] and the colon. The rods and samples are then placed over a piece of filter paper or card into the holding slots in the base of the device. The top of the device is then positioned and serves as a cutting guide. The two angled sections in the center of the top piece are used to guide a knife or scalpel and cut the intestines longitudinally on the top of the rods. Once the intestinal sections have been cut, the top is removed and the card,&#160;tissue and rods gently removed from the device and placed on the bench. The rods are then gently rolled sideways to flatten and stick the intestinal segments onto the underlying piece of filter paper or card. The final preparation can then be examined or fixed and stored for later analysis. The preparations are invaluable for the study of intestinal changes in normal or genetically modified mouse models. The preparations have been used for the study and quantification of the effects of inflammation (colitis), damage, pre-cancerous lesions (aberrant crypt foci (ACFs) and mucin depleted foci (MDFs)) and polyps or tumors.

The use of a simple device to cut and &#8216;roll&#8217; mouse intestines to rapidly prepare whole mount preparations is described.

Um dispositivo simples de preparar rapidamente inteiras Mounts do mouse Intestino

Preparing whole mounts of the mouse small intestine and colon for subsequent analysis or quantification can be time consuming and difficult. We describe ...

A Neonatal Mouse Spinal Cord Compression Injury Model

Spinal cord injury (SCI) typically causes devastating neurological deficits, particularly through damage to fibers descending from the brain to the spinal cord. A major current area of research is focused on the mechanisms of adaptive plasticity that underlie spontaneous or induced functional recovery following SCI. Spontaneous functional recovery is reported to be greater early in life, raising interesting questions about how adaptive plasticity changes as the spinal cord develops. To facilitate investigation of this dynamic, we have developed a SCI model in the neonatal mouse. The model has relevance for pediatric SCI, which is too little studied. Because neural plasticity in the adult involves some of the same mechanisms as neural plasticity in early life1, this model may potentially have some relevance also for adult SCI. Here we describe the entire procedure for generating a reproducible spinal cord compression (SCC) injury in the neonatal mouse as early as postnatal (P) day 1. SCC is achieved by performing a laminectomy at a given spinal level (here described at thoracic levels 9-11) and then using a modified Yasargil aneurysm mini-clip to rapidly compress and decompress the spinal cord. As previously described, the injured neonatal mice can be tested for behavioral deficits or sacrificed for ex vivo physiological analysis of synaptic connectivity using electrophysiological and high-throughput optical recording techniques1. Earlier and ongoing studies using behavioral and physiological assessment have demonstrated a dramatic, acute impairment of hindlimb motility followed by a complete functional recovery within 2 weeks, and the first evidence of changes in functional circuitry at the level of identified descending synaptic connections1.

This article describes a method for generating a reproducible spinal cord compression injury (SCI) in the neonatal mouse. The model provides an advantageous platform for studying mechanisms of adaptive plasticity that underlie spontaneous functional recovery.

A Neonatal do rato Spinal Cord Injury Compression Modelo

Spinal cord injury (SCI) typically causes devastating neurological deficits, particularly through damage to fibers descending from the brain to the spinal ...

Vein Interposition Model: A Suitable Model to Study Bypass Graft Patency

Bypass grafting is an established treatment method for coronary artery disease. Graft patency continues to be the Achilles heel of saphenous vein grafts. Research models for bypass graft failure are essential for a better understanding of pathobiological and pathophysiological processes during graft patency loss. Large animal models, such as pigs or sheep, resemble human anatomical structures but require special facilities and equipment. This video describes a rat vein interposition model to investigate vein graft patency loss. Rats are inexpensive and easy to handle. Compared to mouse models, the convenient size of rats permits better operability and enables a sufficient amount of material to be obtained for further diverse analysis. In brief, the inferior epigastric vein of a donor rat is harvested and used to replace a segment of the femoral artery. Anastomosis is conducted via single stitches and sealed with fibrin glue. Graft patency can be monitored non-invasively using duplex sonography. Myointimal hyperplasia, which is the main cause for graft patency loss, develops progressively over time and can be calculated from histological cross sections.

This video demonstrates a model to study the development of myointimal hyperplasia after venous interposition surgery in rats.

Veia Interposição Modelo: Um modelo adequado para estudar Bypass Graft Perviedade

Bypass grafting is an established treatment method for coronary artery disease. Graft patency continues to be the Achilles heel of saphenous vein grafts. ...

Intranasal Delivery of Therapeutic Stem Cells to Glioblastoma in a Mouse Model

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of therapeutic stem cells via the intranasal route is a recently discovered alternative strategy, with strong potential for clinical translation, due to its non-invasive nature compared to intracranial implantation or delivery via systemic routes. The lack of blood brain barrier further strengthens the therapeutic potential of stem cells undergoing intranasal brain entry. This article summarizes the essential techniques utilized in our studies and outlines the basic principles of intranasal strategy for stem cell delivery using a mouse model of intracranial glioma xenografts. We demonstrate the optimized procedures that generate consistent and reproducible results with specific predetermined experimental parameters and offer guidelines for streamlined work flow that ensure efficient execution and reliable experimental outcome. The article is designed to serve as a baseline for further experimental customization based on hypothesis, stem cell types, or tumor specifics.

Stem cells are promising therapeutic carriers to treat brain tumors due to their intrinsic tumor tropism. Non-invasive intranasal stem cell delivery bypasses the blood brain barrier and demonstrates strong potential for clinical translation. This article summarizes the basic principles of intranasal stem cell delivery in a mouse model of glioma.

Entrega intranasal de células-tronco terapêuticas para Glioblastoma em um modelo de mouse

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of ...