This work was supported by grant from NIDDK (DK065949 for GG). We thank Dr. Brenda M. Jarvis and Jeff Duryea Jr. for reading the manuscript.

utilização de animais segue os procedimentos especificados no protocolo M / 11/181 aprovado pelo Institutional Animal Care e do Comitê Use Vanderbilt para Gu. ratinhos CD1 ou CBA / Bl6 foram adquiridos de fornecedores comerciais e cruzou no biotério Vanderbilt obter camundongos neonatais. 1. Preparação de Ratos, Soluções de Stock, and Equipment <ol><li> Para a cruz mouse: configurar uma cruz mouse e registrar as datas entupimento para auxiliar o planejamento experimental. ratinhos CD1 normalmente dão à luz por volta do dia 19 após o acasalamento. Use CD1 ou CBA / BL6 cruza para obter CD1 ou CBA / Bl6 neonatos, respectivamente. Intercruzamentos entre as duas linhas de utilizar fêmeas CD1 e machos CBA / Bl6. </li><li> Para o estoque de colagenase: pesar 200 mg de colagenase tipo IV com uma balança de alta precisão. Transferir para um tubo de centrífuga de 50 mL. Dissolve-se em 40 ml de HBSS com Ca2 + / Mg2 + (1,26 e 0,5 mM, respectivamente) para produzir uma solução stock de 5 mg / mL. <ol><li> Permitir que a colagenasedissolver para ~ 30 min com agitação suave. Alíquotas e manter a solução congelada em -20 ° C como estoque, que permanece activo durante pelo menos um ano. </li></ol></li><li> Autoclave para esterilizar vários pares de pinças, tesouras e dicas P20 para dissecção e picking ilhéu. </li><li> Para o estoque de glucose 1 H: pesar 9 g de glucose em um tubo de centrífuga de 50 ml, adicionar 50 ml de meio RPMI 1640 para dissolver a glicose. Tenha em 4 ° C até à sua utilização, mas não mais do que 6 meses. </li></ol> 2. As soluções de trabalho NOTA: O dia de isolamento de ilhotas, preparar os seguintes reagentes. <ol><li> Para a solução IV trabalho colagenase tipo: descongelar e diluir estoque colagenase no gelo. Dispensar 0,15 mL estoque em cada tubo de microcentrífuga de 1,7 mL. Adicionar 1,35 mL de HBSS com Ca2 + / Mg2 +. Inverta o tubo 5 vezes. Deixar em gelo durante 15 min. <ol><li> Girar em alta velocidade por 3 min numa microcentrífuga. Transferir o sobrenadante para um novo tubo. Deixar em gelo até à sua utilização. Rejeitar o tubo de detritos insolúveis. </li></ol></li><li> Para completo de mídia RPMI 1640: adicionar 2,5 mL 1 glucose M, 50 mL de calor FBS inactivado, e 5 mL 100x estoque Pen-strep em 500 ml RPMI 1640. Deixar em gelo até à sua utilização. </li></ol> 3. Isolamento pâncreas e Digestão <ol><li> Eutanásia neonatos com isoflurano, seguido por decapitação de acordo com protocolos aprovados. </li><li> Coloque o mouse com a barriga virada para cima. Spray com 70% de etanol para esterilização. </li><li> Levantar a pele de barriga para cima, com uma pinça e cortar as camadas da pele e músculo longitudinalmente ao longo da linha média com um par de tesouras, a partir da área genital para a caixa torácica. Isto abre a cavidade abdominal para expor todos os órgãos internos. </li><li> Transferir todos os órgãos internos, de 100 cm de placa com um par de pinças. Localize o pâncreas, que é um órgão-dispersa com uma porção dorsal que se agarra ao estômago e baço e uma porção ventral que se agarra ao duodeno 11. </li&gt; <li> Adicionar HBSS no prato para submergir os órgãos. Em solução, os tecidos pancreáticos não se agarram ao duodeno, estômago, ou baço. É facilmente reconhecível sob um escopo de dissecação causa de sua cor branca típica. Use um par de pinças para descascar os tecidos pancreáticos longe do tecido circundante e transferir para um novo prato 60 mm, com HBSS. </li><li> Corte cada pâncreas com uma tesoura em pedaços menores que 5 mm em qualquer dimensões. Transferir para um tubo de microcentrífuga de 1,5 mL. Até cinco pancreata (menores de P7) pode ser digerida em um tubo. Para ratos P8-P16, use um tubo por pâncreas. </li><li> Adicionar 0.5 - Solução de trabalho de 1 ml a cada tubo colagenase (0,2 ml para cada pâncreas P1-P7 Utilizar 0,5 mL por cada pâncreas P8-P16.). Deixar o tubo numa incubadora a 37 ° C durante até 15 min. Inverta o tubo duas vezes a cada min. </li><li> Depois de ~ 5 min, toque no tubo para monitorar o estado de digestão do tecido pancreático. Prosseguir o processo de digestão até que a maior parte do pâncreastecido aparece como grupos de células fragmentadas, com diâmetro &lt;2 mm. O ligado aparece turva, o que é devido a autólise celular acinar normal. </li></ol> 4. Lysate de lavar roupa <ol><li> Girar o lisado a 500 xg durante 10 s numa microcentrifuga. Retirar a camada sobrenadante com um Pipetman P1,000. O sobrenadante deve aparecer turva mas desprovido de agregados de células. Não utilizar aspiração, que pode aspirar rapidamente afastado os fragmentos de tecido na parte inferior devido à presença de uma amostra de DNA pegajoso. </li><li> Adicione 1 mL RPMI 1640 mídia completo. Toque suavemente o tubo para voltar a suspender o lisado fragmentado. Inverta cima e para baixo 10 vezes. Repita o passo 4.1. </li><li> Repita o passo 4.2 mais duas vezes ou até que o sobrenadante claro. Re-suspender pancreï¿½ticos lavadas em 1 mL completos RPMI 1640. </li></ol> 5. Isolamento Islet NOTA: Para um pequeno número de pancreata, mão-picking direto como a seguir (5.1) pode ser usado para o isolador do ilhéução. Para grandes números de pâncreas (&gt; 6), é preferido o método descrito no ponto 5.2. <ol><li> mão-picking direto: <ol><li> Transferir o lisado do passo 4.3 para um prato de 60 mm. Adicionar 5 ml completos RPMI 1640. Traga sob um microscópio de dissecação. </li><li> Configurar a iluminação de campo brilhante no microscópio. Ajustar a intensidade da luz de ~ 50% da potência máxima. Sob esta condição, ilhotas aparecer como um pouco cachos cor de rosa, enquanto as células acinares aglomerados de forma irregular como escuras (Figura 1A). A ampliação de ~ 50X (combinando o poder da objetiva e da parte do olho) é recomendado para oferecer a melhor maneira de ilhotas visualização e a abertura ponta da pipeta, simultaneamente, para a colheita. </li><li> Pegar ilhotas com uma ponta de pipeta P20, evitando aglomerados acinares. Fracções dispensar ilhotas enriquecido a um novo prato de 60 milímetros com meio RPMI completo (Figura 1B). </li><li> Repita o processo de mão-picking mais duas vezes. Deixar ilhotas puro em uma nova 60prato mm com 4 ml de meio RPMI completo (Figura 1C). </li></ol></li><li> centrifugação em gradiente: <ol><li> Preparar um tubo de centrífuga de 15 ml que é pré-carregado com 2 mL de polissacarose e diatrizoato de sódio, a uma densidade de 1,077 g / mL. Deixe o tubo em gelo até à sua utilização. </li><li> Transferir a suspensão do passo 4.3 sobre o topo da solução de diatrizoato de sódio e polissacarose com uma pipeta de Pasteur. Não perturbe a camada inferior. Os tecidos de até 10 recém-nascidos ou 2 P17 pancreata pode ser colocada em cada tubo de 15 ml. </li><li> Girar o tubo de a ~ 600 x g num rotor oscilante durante 15 min a 4 ° C. Use as configurações de freio-off. </li><li> Após a centrifugação, transferir a mídia e camadas interfase (note que em condições de operação ideais, as ilhotas será localizado na interfase entre o polissacarose e cultura da mídia após a centrifugação) para um novo tubo de 15 mL. Adicionar 10 ml de mídia, misture delicadamente mas completamente. </li><li> Spin down a fração enriquecida com ilhéua 300 xg durante 5 min. Remova o meio de lavagem. Repetir a lavagem mais uma vez com meio RPMI completo. Pelotas Ressuspender em 4 mL de mídia, que contém a maioria dos ilhéus e dutos (Figura 1D). </li><li> Mão-pegar as ilhotas, conforme descrito na secção 5.1. </li></ol></li></ol> 6. Os ensaios GSIS em isolados Ilhotas <ol><li> Incubar os ilhéus a partir do passo 5.1.4 em meio RPMI completo, durante 2 h num incubador de cultura de tecido C 37 °. </li><li> Usar uma pipeta para remover RPMI sob um microscópio de dissecação. Adiciona-se 3 mL de solução de KRB com glucose 2,8 mM e a placa 3. Agitar 10 vezes para lavar as ilhotas. Remover soluções KRB. <ol><li> Repetir o processo de lavagem uma vez. Incubar as ilhotas com 3 mL de solução de KRB a 37 ° C durante 1 hora numa incubadora. </li></ol></li><li> Aliquota de 1 mL de KRB a cada poço de uma placa de 12 poços. Pré-aqueça o estoque KRB e placa a 37 ° C em uma incubadora. </li><li> Lavar as ilhotas duas vezes com KRB pré-aquecido como em 6.2. transfer 10 ilhotas para cada poço das placas pré-aquecido. Incubar numa incubadora a 37 ° C. </li><li> Após 45 minutos, retirar-se 50 ul de sobrenadante. Este contém a solução de insulina segregada sob basais de glucose. </li><li> Adicionar glucose 32 mL de 500 mM. Agitar a placa 20 vezes para misturar a solução. Incubar numa incubadora a 37 ° C. Agitar a placa 5 vezes a cada 5 min. </li><li> Após 45 minutos, retirar-se 50 uL de sobrenadante. Esta é a insulina segregada sob alto teor de glucose. </li><li> Transfira todas as ilhotas a um tubo de 1,5 mL. Congelar em -20 ° C durante 30 min. Descongelar à temperatura ambiente durante 5 min. Repita o processo de congelamento e descongelamento. </li><li> Adicionar 0,5 mL de etanol a 70% com HCl 20 mM. Deixe durante a noite. Esta é a insulina nas ilhotas. </li><li> Use de ELISA convencional para ensaiar os níveis de insulina, descrito anteriormente 3. </li></ol>

<ol>
	<li>Matsumoto, S., 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=Improvement+of+pancreatic+islet+cell+isolation+for+transplantation.">Improvement of pancreatic islet cell isolation for transplantation.</a> Proc (Bayl Univ Med Cent). 20 (4), 357-362 (2007).</li><li>Zmuda, E. J., Powell, C. A., Hai, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+for+murine+islet+isolation+and+subcapsular+kidney+transplantation.">A method for murine islet isolation and subcapsular kidney transplantation.</a> J Vis Exp. (50), (2011).</li><li>Zhao, 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=Galphao+represses+insulin+secretion+by+reducing+vesicular+docking+in+pancreatic+beta-cells.">Galphao represses insulin secretion by reducing vesicular docking in pancreatic beta-cells.</a> Diabetes. 59 (10), 2522-2529 (2010).</li><li>Planas, R., 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=Gene+expression+profiles+for+the+human+pancreas+and+purified+islets+in+type+1+diabetes:+new+findings+at+clinical+onset+and+in+long-standing+diabetes.">Gene expression profiles for the human pancreas and purified islets in type 1 diabetes: new findings at clinical onset and in long-standing diabetes.</a> Clin Exp Immunol. 159 (1), 23-44 (2010).</li><li>Tonne, J. M., 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=Global+gene+expression+profiling+of+pancreatic+islets+in+mice+during+streptozotocin-induced+beta-cell+damage+and+pancreatic+Glp-1+gene+therapy.">Global gene expression profiling of pancreatic islets in mice during streptozotocin-induced beta-cell damage and pancreatic Glp-1 gene therapy.</a> Dis Model Mech. 6 (5), 1236-1245 (2013).</li><li>London, N. J., Swift, S. M., Clayton, H. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation,+culture+and+functional+evaluation+of+islets+of+Langerhans.">Isolation, culture and functional evaluation of islets of Langerhans.</a> Diabetes Metab. 24 (3), 200-207 (1998).</li><li>Rorsman, 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=Failure+of+glucose+to+elicit+a+normal+secretory+response+in+fetal+pancreatic+beta+cells+results+from+glucose+insensitivity+of+the+ATP-regulated+K++channels.">Failure of glucose to elicit a normal secretory response in fetal pancreatic beta cells results from glucose insensitivity of the ATP-regulated K+ channels.</a> Proc Natl Acad Sci U S A. 86 (12), 4505-4509 (1989).</li><li>Hellerstrom, C., Swenne, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+maturation+and+proliferation+of+fetal+pancreatic+beta-cells.">Functional maturation and proliferation of fetal pancreatic beta-cells.</a> Diabetes. 40 (Suppl 2), 89-93 (1991).</li><li>Blum, B., 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=Functional+beta-cell+maturation+is+marked+by+an+increased+glucose+threshold+and+by+expression+of+urocortin+3.">Functional beta-cell maturation is marked by an increased glucose threshold and by expression of urocortin 3.</a> Nat Biotechnol. 30 (3), 261-264 (2012).</li><li>Hegre, O. D., 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=Nonenzymic+in+vitro+isolation+of+perinatal+islets+of+Langerhans.">Nonenzymic in vitro isolation of perinatal islets of Langerhans.</a> In Vitro. 19 (8), 611-620 (1983).</li><li>Dolen&#353;ek, J., Rupnik, M. A., Sto&#382;er, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+similarities+and+differences+between+the+human+and+the+mouse+pancreas.">Structural similarities and differences between the human and the mouse pancreas.</a> Islets. 7 (1), e102445 (2015).</li><li>White, J., White, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Source Book of Enzymes, Source Book of Enzymes. , (1997).</li><li>Bock, T., Pakkenberg, B., Buschard, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+background+determines+the+size+and+structure+of+the+endocrine+pancreas.">Genetic background determines the size and structure of the endocrine pancreas.</a> Diabetes. 54 (1), 133-137 (2005).</li><li>Bouwens, L., Rooman, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+pancreatic+beta-cell+mass.">Regulation of pancreatic beta-cell mass.</a> Physiol Rev. 85 (4), 1255-1270 (2005).</li></ol>

The authors declare no competing financial interests for the described work.

Aqui, nós fornecemos um protocolo passo-a-passo de isolamento de ilhotas de pâncreas que são demasiado pequenos para perfusão convencional. Espera-se, para se obter ilhotas prontos para todos os estudos baseados em purificação de ilhotas, tais como beta-célula, a análise da expressão do gene, a maturação das células beta dos ilhéus pancreáticos, proliferação, as respostas de stress celular, sobrevivência celular, metabolismo, e manutenção GSIS funcional, etc. Este será, para o melhor do noss...

Isolating pure pancreatic islets is essential for assaying glucose stimulated insulin secretion (GSIS) of beta cells and for islet transplantation from cadaveric donors 1-3. It is also necessary to establish endocrine gene expression in islet cells 4, 5. For this purpose, detailed protocols have been established to allow for isolation of pancreatic islets from large pancreata (6 and references therein). These methods are based on enzymatic perfusion to dissociate acinar from islet tissues, coupled with gradient separation and hand picking. Thus, islet isolation from large pancreas can be performed readily in most laboratories. On the other hand, no detailed step-by-step protocol exists to allow for the isolation of islets from pancreata that are too small to perfuse.
Studying gene expression and function of neonatal islets is important. Neonate islets have different properties from adults in insulin secretion and proliferation capability 7, 8. However, isolating islets from newly born animals, especially mice is challenging due to the small size of the newly born pancreas. The size prevents the usual perfusion process when collagenase is injected though the pancreatic duct. Indeed, several papers have presented studies along these lines, with enzyme or non-enzyme aided isolation procedures 7, 9, 10. However, detailed description of the islet isolation process with visual aid is lacking 7, 9, making it a challenge for most researchers to perform similar studies. 
We have explored several different conditions that yield high quality islets from neonatal mice. Here we present a protocol that is expected to help researchers learn the key details in the islet isolation process. This protocol is applicable to mouse pancreas up to two weeks of age, after which perfusion can be performed for routine islet isolation. Islets can be directly used for insulin secretion and gene expression assays.

<table border="0" cellpadding="0" cellspacing="0" width="769">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Collagenase&#160; Type IV</td>
			<td style="width:253px;">Sigma Aldrich, St Louis, MO</td>
			<td style="width:128px;">C5138</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:169px;">1X HBSS with Ca2+/Mg2+</td>
			<td style="width:253px;">Mediatech/Cellgro, Manassas, VA</td>
			<td>MT21020CV</td>
			<td style="width:219px;">If HBSS wihout Ca2+/Mg2+ is obtained, CaCl2 and MgSO4 can be added to 1.26 and 0.5 mM, respectively.&#160;</td>
		</tr>
		<tr height="51">
			<td height="51" style="height:51px;width:169px;">RPMI 1640 w/o glucose</td>
			<td style="width:253px;">Thermo Fisher Scientific/Life Technologies, Waltham, MA</td>
			<td>11879-020</td>
			<td style="width:219px;">Glucose needs to be added to specific levels to not interfere with seusequent islet usage.&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Glucose</td>
			<td style="width:253px;">Sigma Aldrich, St Louis, MO</td>
			<td>G-7021&#160;</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:169px;">polysucrose and sodium diatrizoate solution</td>
			<td style="width:253px;">Sigma Aldrich, St Louis, MO</td>
			<td>Histopaque-10771</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Stereoscope</td>
			<td style="width:253px;">Carl-Zeiss, Oberkochen, Germany</td>
			<td>Stemi2000</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Stereoscope</td>
			<td style="width:253px;">Leica, Wetzlar, Germany</td>
			<td>Leica M165</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Microcentrifuge</td>
			<td style="width:253px;">Eppendorf, Hauppauge, NY</td>
			<td>Centrifuge 5417C</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Centrfuge</td>
			<td style="width:253px;">Eppendorf, Hauppauge, NY</td>
			<td>Centrifuge 5810R</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">15-ml centrfuge tubes&#160;</td>
			<td style="width:253px;">VWR, Radnor, PA</td>
			<td>89039-666</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">50-ml centrfuge tubes&#160;</td>
			<td style="width:253px;">VWR, Radnor, PA</td>
			<td>89039-658</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Precision balance</td>
			<td style="width:253px;">VWR, Radnor, PA</td>
			<td>VWR-225AC</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Microfuge tubes</td>
			<td style="width:253px;">VWR, Radnor, PA</td>
			<td>87003-294</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Pipetman P1000</td>
			<td style="width:253px;">Fisher Scientific,&#160; Waltham, MA</td>
			<td>F123602</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Pipetman P20</td>
			<td style="width:253px;">Fisher Scientific,&#160; Waltham, MA</td>
			<td>F123600</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">100X15 millimeter dish</td>
			<td style="width:253px;">VWR, Radnor, PA</td>
			<td>25384-088</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">60X15 millimeter dish</td>
			<td style="width:253px;">VWR, Radnor, PA</td>
			<td>25384-168</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:19px;width:169px;">12-well plates</td>
			<td style="width:253px;">VWR, Radnor, PA</td>
			<td>665-180</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:19px;width:169px;">Scissor</td>
			<td style="width:253px;">Fine Scientific Tools, Foster City, CA</td>
			<td>14080-11</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:169px;">Tweezers</td>
			<td style="width:253px;">Fine Scientific Tools, Foster City, CA</td>
			<td>5708-5</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:19px;width:169px;">CD1 mice</td>
			<td style="width:253px;">Charles River Laboratories, Wilminton, MA&#160;</td>
			<td>CD-1</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:19px;width:169px;">C57BL/6J</td>
			<td style="width:253px;">The Jackson laboratory, Farmington, CT&#160;</td>
			<td>C57BL/6J</td>
			<td style="width:219px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:169px;">B6CBAF1/J</td>
			<td style="width:253px;">The Jackson laboratory, Farmington, CT&#160;</td>
			<td>B6CBAF1/J</td>
			<td style="width:219px;"></td>
		</tr>
	</tbody>
</table>

effective isolation of functional islets from neonatal mouse pancreas

protocolos de isolamento de ilhotas-à base de perfusão de grande pâncreas de mamíferos estão bem estabelecidos. Tais protocolos estão prontamente realizado em muitos laboratórios, devido ao grande tamanho do ducto pancreático que permite a injecção pronto colagenase e subsequente perfusão tecidual. Em contraste, o isolamento de ilhotas do pâncreas pequena, como a de ratinhos neonatais, é um desafio porque perfusão não é facilmente realizável na pequena pâncreas. Aqui nós descrevemos um procedimento simples detalhado que recupera um número substancial de ilhotas de ratos recém-nascidos com assistência visual. pancreata inteiro recentemente dissecados foram digeridos com 0,5 mg / ml de colagenase IV dissolvido em Hanks &#39;Solução Salina Equilibrada (SSHE) a 37 ° C, em tubos de microcentrífuga. Os tubos foram aproveitado regularmente para ajudar a dispersão do tecido. Quando a maior parte do tecido foi disperso em pequenos aglomerados de cerca de 1 mM, lisados ​​foram lavados três a quatro vezes com meio de cultura com 10% de soro fetal de bovino (FBS). aglomerados de ilhotas,desprovidas de tecidos acinares reconhecíveis, pode então ser recuperado sob dissecando estereoscópio. Este método recupera 20 - 80 pequenas e ilhotas de grande porte por pâncreas de rato recém-nascido. Estas ilhotas são adequadas para ensaios a jusante mais possíveis, incluindo a secreção de insulina, a expressão do gene, e a cultura. Um exemplo do ensaio de secreção de insulina é apresentado para validar o processo de isolamento. O fundo genético e grau de digestão são os maiores fatores determinantes do rendimento. solução de colagenase recentemente feito com alta atividade é preferível, uma vez que auxilia no isolamento endócrino-exócrina. A presença de catiões [cálcio (Ca2 +) e magnésio (Mg2 +)] em todas as soluções e soro fetal de bovino na lavagem / meios de recolha são necessárias para um bom rendimento de ilhotas com integridade adequada. Um escopo de dissecação com bom contraste e ampliação também vai ajudar.

Em condições óptimas, o método apresentado pode rendimento de 20 - 80 de cada pequena ilhotas do pâncreas do rato. Este número depende do fundo genético, idade de ratinhos, e o tamanho das ilhotas para ser recuperado. Entre os comumente usados, CD1 fora de raça C57BL / 6J de raça pura produzem menos ilhotas com tamanho menor do que híbridos entre CD1 e C57BL / 6 ou B6CBAF1 comercial / mice J fazer. Mão directa colheita geralmente deu um menor número de ilhotas, provavelmente ...

Watch this Scientific Journal Video about Effective Isolation of Functional Islets from Neonatal Mouse Pancreas at JoVE.com

Effective Isolation of Functional Islets from Neonatal Mouse Pancreas

Nós descrevemos um protocolo aqui para isolar ilhotas intactas de ratos recém-nascidos. Pâncreas foi parcialmente digerido com colagenase, seguido por lavagem e colheita manual. 20 - 80 agrupamentos de ilhéus podem ser obtidos por pâncreas de ratinhos recém-nascidos, que são adequados para vários estudos da ilhota.

Isolamento eficaz de ilhotas funcionais a partir de ratinho neonato Pâncreas

Perfusion-based islet-isolation protocols from large mammalian pancreata are well established. Such protocols are readily conducted in many laboratories ...

effective-isolation-of-functional-islets-from-neonatal-mouse-pancreas

Research

JoVE Journal

Developmental Biology

10.0K visualizações.  Vanderbilt University Medical School.  Nós descrevemos um protocolo aqui para isolar ilhotas intactas de ratos recém-nascidos. Pâncreas foi parcialmente digerido com colagenase, seguido por lavagem e colheita manual. 20 - 80 agrupamentos de ilhéus podem ser obtidos por pâncreas de ratinhos recém-nascidos, que são adequados para vários estudos da ilhota. 

Vídeo: Effective Isolation of Functional Islets from Neonatal Mouse Pancreas

Isolation and Cryopreservation of Neonatal Rat Cardiomyocytes

Cell culture has become increasingly important in cardiac research, but due to the limited proliferation of cardiomyocytes, culturing cardiomyocytes is difficult and time consuming. The most commonly used cells are neonatal rat cardiomyocytes (NRCMs), which require isolation every time cells are needed. The birth of the rats can be unpredictable. Cryopreservation is proposed to allow for cells to be stored until needed, yet freezing/thawing methods for primary cardiomyocytes are challenging due to the sensitivity of the cells. Using the proper cryoprotectant, dimethyl sulfoxide (DMSO), cryopreservation was achieved. By slowly extracting the DMSO while thawing the cells, cultures were obtained with viable NRCMs. NRCM phenotype was verified using immunocytochemistry staining for &#945;-sarcomeric actinin. In addition, cells also showed spontaneous contraction after several days in culture. Cell viability after thawing was acceptable at 40-60%. In spite of this, the methods outlined allow one to easily cryopreserve and thaw NRCMs. This gives researchers a greater amount of flexibility in planning experiments as well as reducing the use of animals.

The isolation of neonatal rat cardiomyocytes is a time consuming and unpredictable procedure. This study describes methods for cryopreservation and thawing of neonatal rat cardiomyocytes that allows for more efficient use of cells. The thawed NRCMs can be used for various experiments without the need for performing isolations each time.

O isolamento e criopreservação de Neonatais Rato Cardiomyocytes

Cell culture has become increasingly important in cardiac research, but due to the limited proliferation of cardiomyocytes, culturing cardiomyocytes is ...

Biologia do Desenvolvimento

Isolation and Characterization of Single Cells from Zebrafish Embryos

The zebrafish (Danio rerio) is a powerful model organism to study vertebrate development. Though many aspects of zebrafish embryonic development have been described at the morphological level, little is known about the molecular basis of cellular changes that occur as the organism develops. With recent advancements in microfluidics and multiplexing technologies, it is now possible to characterize gene expression in single cells. This allows for investigation of heterogeneity between individual cells of specific cell populations to identify and classify cell subtypes, characterize intermediate states that occur during cell differentiation, and explore differential cellular responses to stimuli. This study describes a protocol to isolate viable, single cells from zebrafish embryos for high throughput multiplexing assays. This method may be rapidly applied to any zebrafish embryonic cell type with fluorescent markers. An extension of this method may also be used in combination with high throughput sequencing technologies to fully characterize the transcriptome of single cells. As proof of principle, the relative abundance of cardiac differentiation markers was assessed in isolated, single cells derived from nkx2.5 positive cardiac progenitors. By evaluation of gene expression at the single cell level and at a single time point, the data support a model in which cardiac progenitors coexist with differentiating progeny. The method and work flow described here is broadly applicable to the zebrafish research community, requiring only a labeled transgenic fish line and access to microfluidics technologies.

This protocol describes a method for isolating single cells from zebrafish embryos, enriching for cells of interest, capturing zebrafish cells in microfluidic based single cell multiplex systems, and assessing gene expression from single cells.

Isolamento e caracterização de células individuais de embriões Zebrafish

The zebrafish (Danio rerio) is a powerful model organism to study vertebrate development. Though many aspects of zebrafish embryonic development have been ...

In Vitro Colony Assays for Characterizing Tri-potent Progenitor Cells Isolated from the Adult Murine Pancreas

Stem and progenitor cells from the adult pancreas could be a potential source of therapeutic beta-like cells for treating patients with type 1 diabetes. However, it is still unknown whether stem and progenitor cells exist in the adult pancreas. Research strategies using cre-lox lineage-tracing in adult mice have yielded results that either support or refute the idea that beta cells can be generated from the ducts, the presumed location where adult pancreatic progenitors may reside. These in vivo cre-lox lineage-tracing methods, however, cannot answer the questions of self-renewal and multi-lineage differentiation-two criteria necessary to define a stem cell. To begin addressing this technical gap, we devised 3-dimensional colony assays for pancreatic progenitors. Soon after our initial publication, other laboratories independently developed a similar, but not identical, method called the organoid assay. Compared to the organoid assay, our method employs methylcellulose, which forms viscous solutions that allow the inclusion of extracellular matrix proteins at low concentrations. The methylcellulose-containing assays permit easier detection and analyses of progenitor cells at the single-cell level, which are critical when progenitors constitute a small sub-population, as is the case for many adult organ stem cells. Together, results from several laboratories demonstrate in vitro self-renewal and multi-lineage differentiation of pancreatic progenitor-like cells from mice. The current protocols describe two methylcellulose-based colony assays to characterize mouse pancreatic progenitors; one contains a commercial preparation of murine extracellular matrix proteins and the other an artificial extracellular matrix protein known as a laminin hydrogel. The techniques shown here are 1) dissociation of the pancreas and sorting of CD133+Sox9/EGFP+ ductal cells from adult mice, 2) single cell manipulation of the sorted cells, 3) single colony analyses using microfluidic qRT-PCR and whole-mount immunostaining, and 4) dissociation of primary colonies into single-cell suspensions and re-plating into secondary colony assays to assess self-renewal or differentiation.

In Vitro Colony Assays for Characterizing Tri-potent Progenitor Cells Isolated from the Adult Murine Pancreas

In vitro colony assays to detect self-renewal and differentiation of progenitor cells isolated from adult murine pancreas are devised. In these assays, pancreatic progenitors give rise to cell colonies in 3-dimensional space in methylcellulose-containing semi-solid medium. Protocols for handling single cells and characterization of individual colonies are described.

In Vitro Colony Os ensaios para a caracterização de células progenitoras Tri-potentes Isolado das adultas murino Pâncreas

Stem and progenitor cells from the adult pancreas could be a potential source of therapeutic beta-like cells for treating patients with type 1 diabetes. ...

Isolation of Murine Embryonic Hemogenic Endothelial Cells

The specification of hemogenic endothelial cells from embryonic vascular endothelium occurs during brief developmental periods within distinct tissues, and is necessary for the emergence of definitive HSPC from the murine extra embryonic yolk sac, placenta, umbilical vessels, and the embryonic aorta-gonad-mesonephros (AGM) region. The transient nature and small size of this cell population renders its reproducible isolation for careful quantification and experimental applications technically difficult. We have established a fluorescence-activated cell sorting (FACS)-based protocol for simultaneous isolation of hemogenic endothelial cells and HSPC during their peak generation times in the yolk sac and AGM. We demonstrate methods for dissection of yolk sac and AGM tissues from mouse embryos, and we present optimized tissue digestion and antibody conjugation conditions for maximal cell survival prior to identification and retrieval via FACS. Representative FACS analysis plots are shown that identify the hemogenic endothelial cell and HSPC phenotypes, and describe a methylcellulose-based assay for evaluating their blood forming potential on a clonal level.

Hematopoietic stem and progenitor cells (HSPC) derive from specialized (hemogenic) endothelial cells during development, yet little is known about the process by which some endothelial cells specify to become blood forming. We demonstrate a flow-cytometry based method allowing simultaneous isolation of hemogenic endothelial cells and HSPC from murine embryonic tissues.

Isolamento de células embrionárias de murino hegemônicos endoteliais

The specification of hemogenic endothelial cells from embryonic vascular endothelium occurs during brief developmental periods within distinct tissues, ...

Isolation of Type I and Type II Pericytes from Mouse Skeletal Muscles

Pericytes are perivascular multipotent cells that show heterogeneity in different organs or even within the same tissue. In skeletal muscles, there are at least two pericyte subpopulations (called type I and type II), which express different molecular markers and have distinct differentiation capabilities. Using NG2-DsRed and Nestin-GFP double-transgenic mice, type I (NG2-DsRed+Nestin-GFP-) and type II (NG2-DsRed+Nestin-GFP+) pericytes have been successfully isolated. However, the availability of these double-transgenic mice prevents the widespread use of this purification method. This work describes an alternative protocol that allows for the easy and simultaneous isolation of type I and type II pericytes from skeletal muscles. This protocol utilizes the fluorescence-activated cell sorting (FACS) technique and targets PDGFR&#946;, rather than NG2, together with the Nestin-GFP signal. Following isolation, type I and type II pericytes show distinct morphologies. In addition, type I and type II pericytes isolated with this new method, like those isolated from the double-transgenic mice, are adipogenic and myogenic, respectively. These results suggest that this protocol can be used to isolate pericyte subpopulations from skeletal muscles and possibly from other tissues.

This work describes a FACS-based protocol that allows for easy and simultaneous isolation of type I and type II pericytes from skeletal muscles.

Isolamento de Pericitos Tipo I e Tipo II de Músculos Esqueléticos de Rato

Pericytes are perivascular multipotent cells that show heterogeneity in different organs or even within the same tissue. In skeletal muscles, there are at ...

Fetal Mouse Cardiovascular Imaging Using a High-frequency Ultrasound (30/45MHZ) System

Congenital heart defects (CHDs) are the most common cause of childhood morbidity and early mortality. Prenatal detection&#160;of the underlying molecular mechanisms of CHDs is&#160;crucial for inventing new preventive and therapeutic strategies. Mutant mouse models are powerful tools to discover new&#160;mechanisms&#160;and environmental stress modifiers that drive cardiac development and their potential&#160;alteration in CHDs. However, efforts to establish the causality of these putative contributors have been limited to histological&#160;and molecular studies&#160;in non-survival animal experiments, in which&#160;monitoring the key physiological and hemodynamic parameters is&#160;often absent. Live imaging technology has become an essential tool to establish the&#160;etiology of CHDs. In particular,&#160;ultrasound imaging can be used prenatally without surgically exposing the fetuses,&#160;allowing maintaining&#160;their baseline physiology while monitoring the impact of environmental stress&#160;on the hemodynamic and structural aspects of cardiac chamber development. Herein, we use the High-Frequency Ultrasound (30/45)&#160;system to examine the cardiovascular system in fetal mice at E18.5 in utero at the baseline and in response to prenatal hypoxia exposure. We demonstrate the feasibility of the system to measure cardiac chamber size, morphology, ventricular function, fetal heart rate, and umbilical artery flow indices, and their alterations in fetal mice exposed to systemic chronic hypoxia in utero in real time.

Fetal Mouse Cardiovascular Imaging Using a High-frequency Ultrasound 30/45MHZ System

High-frequency ultrasound imaging of the fetal mouse has improved imaging resolution and can provide precise non-invasive characterization of cardiac development and structural defects. The protocol outlined herein is designed to perform real-time fetal mice echocardiography in vivo.

Imagem cardiovascular fetal de camundongo usando um sistema de ultrassom de alta frequência (30/45MHZ)

Congenital heart defects (CHDs) are the most common cause of childhood morbidity and early mortality. Prenatal detection&#160;of the underlying molecular ...

Efficient Generation of Pancreas/Duodenum Homeobox Protein 1+ Posterior Foregut/Pancreatic Progenitors from hPSCs in Adhesion Cultures

Human pluripotent stem cell (hPSC)-derived pancreatic cells are a promising cell source for regenerative medicine and a platform to study human developmental processes. Stepwise directed differentiation that recapitulates developmental processes is one of the major ways to generate pancreatic cells including pancreas/duodenum homeobox protein 1+ (PDX1+) pancreatic progenitor cells. Conventional protocols initiate the differentiation with small colonies shortly after the passage. However, in the state of colonies or aggregates, cells are prone to heterogeneities, which might hamper the differentiation to PDX1+ cells. Here, we present a detailed protocol to differentiate hPSCs into PDX1+ cells. The protocol consists of four steps and initiates the differentiation by seeding dissociated single cells. The induction of SOX17+ definitive endoderm cells was followed by the expression of two primitive gut tube markers, HNF1&#946; and HNF4&#945;, and eventual differentiation into PDX1+ cells. The present protocol provides easy handling and may improve and stabilize the differentiation efficiency of some hPSC lines that were previously found to differentiate inefficiently into endodermal lineages or PDX1+ cells.

Efficient Generation of Pancreas/Duodenum Homeobox Protein 1+ Posterior Foregut/Pancreatic Progenitors from hPSCs in Adhesion Cultures

Here, we present a detailed protocol to differentiate human pluripotent stem cells (hPSCs) into pancreas/duodenum homeobox protein 1+ (PDX1+) cells for the generation of pancreatic lineages based on the non-colony type monolayer growth of dissociated single cells. This method is suitable for producing homogenous hPSC-derived cells, genetic manipulation and screening.

Eficiente geração de pâncreas/duodeno Homeobox proteína 1+ Posterior Foregut/pancreático progenitores de hPSCs em culturas de adesão

Human pluripotent stem cell (hPSC)-derived pancreatic cells are a promising cell source for regenerative medicine and a platform to study human ...

Isolation of Specific Neuron Populations from Roundworm Caenorhabditis elegans

During the aging process, many cells accumulate high levels of damage leading to cellular dysfunction, which underlies many geriatric and pathological conditions. Post-mitotic neurons represent a major cell type affected by aging. Although multiple mammalian models of neuronal aging exist, they are challenging and expensive to establish. The roundworm Caenorhabditis elegans is a powerful model to study neuronal aging, as these animals have short lifespan, an available robust genetic toolbox, and well-cataloged nervous system. The method presented herein allows for seamless isolation of specific cells based on the expression of a transgenic green fluorescent protein (GFP). Transgenic animal lines expressing GFP under distinct, cell type-specific promoters are digested to remove the outer cuticle and gently mechanically disrupted to produce slurry containing various cell types. The cells of interest are then separated from non-target cells through fluorescence-activated cell sorting, or by anti-GFP-coupled magnetic beads. The isolated cells can then be cultured for a limited time or immediately used for cell-specific ex vivo analyses such as transcriptional analysis by real time quantitative PCR. Thus, this protocol allows for rapid and robust analysis of cell-specific responses within different neuronal populations in C. elegans.

Isolation of Specific Neuron Populations from Roundworm Caenorhabditis elegans

Here, we present a protocol for simple isolation of specific groups of live neuronal cells expressing green fluorescent protein from transgenic Caenorhabditis elegans lines. This method enables a variety of ex vivo studies focused on specific neurons and has the capacity to isolate cells for further short-term culturing.

Isolação de populações específicas do Neuron do elegans da Caenorhabditis da lombriga

During the aging process, many cells accumulate high levels of damage leading to cellular dysfunction, which underlies many geriatric and pathological ...

Isolation and Differentiation of Primary Myoblasts from Mouse Skeletal Muscle Explants

Primary myoblasts are undifferentiated proliferating precursors of skeletal muscle. They can be cultured and studied as muscle precursors or induced to differentiate into later stages of muscle development. The protocol provided here describes a robust method for the isolation and culture of a highly proliferative population of myoblast cells from young adult mouse skeletal muscle explants. These cells are useful for the study of the metabolic properties of skeletal muscle of different mouse models, as well as in other downstream applications such as transfection with exogenous DNA or transduction with viral expression vectors. The level of differentiation and metabolic profile of these cells depends on the length of exposure, and composition of the media used to induce myoblast differentiation. These methods provide a robust system for the study of mouse muscle cell metabolism ex vivo. Importantly, unlike in vivo models, the methods described here provide a cell population that can be expanded and studied with high levels of reproducibility.

Myoblasts are proliferating precursor cells that differentiate to form polynucleated myotubes and eventually skeletal muscle myofibers. Here, we present a protocol for efficient isolation and culture of primary myoblasts from young adult mouse skeletal muscles. The method enables molecular, genetic, and metabolic studies of muscle cells in culture.

Isolamento e diferenciação de Mioblasts primários de explantes do músculo esquelético do rato

Primary myoblasts are undifferentiated proliferating precursors of skeletal muscle. They can be cultured and studied as muscle precursors or induced to ...

A Simple and Effective Transplantation Device for Zebrafish Embryos

Classical embryological manipulations, such as removing cells and transplanting cells within or between embryos, are powerful techniques to study complex developmental processes. Zebrafish embryos are ideally suited for these manipulations since they are easily accessible, relatively large in size, and transparent. However, previously developed devices for cell removal and transplantation are cumbersome to use or expensive to purchase. In contrast, the transplantation device presented here is economical, easy to assemble, and simple to use. In this protocol, we first introduce the handling of the transplantation device as well as its assembly from commercially and widely available parts. We then present three applications for its use: generation of ectopic clones to study signal dispersal from localized sources, extirpation of cells to produce size-reduced embryos, and germline transplantation to generate maternal-zygotic mutants. Finally, we show that the tool can also be used for embryological manipulations in other species such as the Japanese rice fish medaka.

Embryological manipulations such as extirpation and transplantation of cells are important tools to study early development. This protocol describes a simple and effective transplantation device to perform these manipulations in zebrafish embryos.

Um dispositivo de transplante simples e eficaz para embriões de zebrafish

Classical embryological manipulations, such as removing cells and transplanting cells within or between embryos, are powerful techniques to study complex ...