Este trabajo fue apoyado por becas de JLRR de: Autism Speaks, Nina Irlanda, Weston Havens Fundación, NIMH R01 MH081880, y NIMH R37 MH049428. PRW fue apoyado por una beca del Consejo Nacional de Ciencia de Taiwán. SFS fue apoyada por F32 (MH103003).

<ol>
	<li>Huang, Z. J., Di Cristo, G., Ango, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+GABA+innervation+in+the+cerebral+and+cerebellar+cortices.">Development of GABA innervation in the cerebral and cerebellar cortices.</a> Nat. Rev. Neurosci. 8 (9), 673-686 (2007).</li><li>Rubenstein, J. L. R., Merzenich, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Model+of+autism:+increased+ratio+of+excitation/inhibition+in+key+neural+systems.">Model of autism: increased ratio of excitation/inhibition in key neural systems.</a> Genes, brain, and behavior. 2 (5), 255-267 (2003).</li><li>Anderson, S. A., Eisenstat, D. D., Shi, L., Rubenstein, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interneuron+migration+from+basal+forebrain+to+neocortex:+dependence+on+Dlx+genes.">Interneuron migration from basal forebrain to neocortex: dependence on Dlx genes.</a> Science. 278 (5337), 474-476 (1997).</li><li>Wonders, C. P., Anderson, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+origin+and+specification+of+cortical+interneurons.">The origin and specification of cortical interneurons.</a> Nat. Rev. Neurosci. 7 (9), 687-696 (2006).</li><li>Gelman, 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=A+Wide+Diversity+of+Cortical+GABAergic+Interneurons+Derives+from+the+Embryonic+Preoptic+Area.">A Wide Diversity of Cortical GABAergic Interneurons Derives from the Embryonic Preoptic Area.</a> J. Neurosci. 31 (46), 16570-16580 (2011).</li><li>Miyoshi, G., 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=Genetic+fate+mapping+reveals+that+the+caudal+ganglionic+eminence+produces+a+large+and+diverse+population+of+superficial+cortical+interneurons.">Genetic fate mapping reveals that the caudal ganglionic eminence produces a large and diverse population of superficial cortical interneurons.</a> J. Neurosci. 30 (5), 1582-1594 (2010).</li><li>Batista-Brito, R., Fishell, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+developmental+integration+of+cortical+interneurons+into+a+functional+network.">The developmental integration of cortical interneurons into a functional network.</a> Curr. Top. Dev. Bio. 87, 81-118 (2009).</li><li>Inan, M., Welagen, J., Anderson, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+and+Temporal+Bias+in+the+Mitotic+Origins+of+Somatostatin.">Spatial and Temporal Bias in the Mitotic Origins of Somatostatin.</a> and Parvalbumin-Expressing Interneuron Subgroups and the Chandelier Subtype in the Medial Ganglionic. 22 (4), 820-827 (2012).</li><li>Taniguchi, 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=A+Resource+of+Cre+Driver+Lines+for+Genetic+Targeting+of+GABAergic+Neurons+in+Cerebral+Cortex.">A Resource of Cre Driver Lines for Genetic Targeting of GABAergic Neurons in Cerebral Cortex.</a> Neuron. 71 (6), 995-1013 (2011).</li><li>Madisen, L., 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+robust+and+high-throughput+Cre+reporting+and+characterization+system+for+the+whole+mouse+brain.">A robust and high-throughput Cre reporting and characterization system for the whole mouse brain.</a> Nature Neuroscience. 13 (1), 133-140 (2010).</li><li>Hippenmeyer, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+developmental+switch+in+the+response+of+DRG+neurons+to+ETS+transcription+factor+signaling.">A developmental switch in the response of DRG neurons to ETS transcription factor signaling.</a> PLoS Bio. 3 (5), e159 (2005).</li><li>Southwell, D. G., 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=Interneurons+from+embryonic+development+to+cell-based+therapy.">Interneurons from embryonic development to cell-based therapy.</a> Science. 344 (6180), 1240622 (2014).</li><li>Hunt, R. F., Girskis, K. M., Rubenstein, J. L., Alvarez-Buylla, A., Baraban, 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=GABA+progenitors+grafted+into+the+adult+epileptic+brain+control+seizures+and+abnormal.">GABA progenitors grafted into the adult epileptic brain control seizures and abnormal.</a> Nature Neuroscience. 16 (6), 692-697 (2013).</li><li>Braz, 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=Forebrain+GABAergic+Neuron+Precursors+Integrate+into+Adult+Spinal+Cord+and+Reduce+Injury-Induced+Neuropathic+Pain.">Forebrain GABAergic Neuron Precursors Integrate into Adult Spinal Cord and Reduce Injury-Induced Neuropathic Pain.</a> Neuron. 74, 663-675 (2012).</li><li>Vogt, 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=Lhx6+Directly+Regulates+Arx+and+CXCR7+to+Determine+Cortical+Interneuron+Fate+and+Laminar+Position.">Lhx6 Directly Regulates Arx and CXCR7 to Determine Cortical Interneuron Fate and Laminar Position.</a> Neuron. 82 (2), 350-364 (2014).</li><li>Alvarez-Dolado, 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=Cortical+inhibition+modified+by+embryonic+neural+precursors+grafted+into+the+postnatal+brain.">Cortical inhibition modified by embryonic neural precursors grafted into the postnatal brain.</a> J. Neurosci. 26 (4), 7380-7389 (2006).</li><li>Du, T., Xu, Q., Ocbina, P. J., Anderson, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NKX2.1+specifies+cortical+interneuron+fate+by+activating+Lhx6.">NKX2.1 specifies cortical interneuron fate by activating Lhx6.</a> Development. 135 (8), 1559-1567 (2008).</li><li>Arguello, 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=Dapper+Antagonist+of+Catenin-1+Cooperates+with+Dishevelled-1+during+Postsynaptic+Development+in+Mouse+Forebrain+GABAergic+Interneurons.">Dapper Antagonist of Catenin-1 Cooperates with Dishevelled-1 during Postsynaptic Development in Mouse Forebrain GABAergic Interneurons.</a> PLoS ONE. 8 (6), e67679 (2013).</li><li>Lee, 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=Pyramidal+neurons+in+prefrontal+cortex+receive+subtype-specific+forms+of+excitation+and+inhibition.">Pyramidal neurons in prefrontal cortex receive subtype-specific forms of excitation and inhibition.</a> Neuron. 81 (1), 61-68 (2014).</li><li>Chen, Y. J. 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=Use+of+&#8220;MGE+Enhancers&#8221;+for+Labeling+and+Selection+of+Embryonic+Stem+Cell-Derived+Medial+Ganglionic+Eminence+(MGE)+Progenitors+and+Neurons.">Use of &#8220;MGE Enhancers&#8221; for Labeling and Selection of Embryonic Stem Cell-Derived Medial Ganglionic Eminence (MGE) Progenitors and Neurons.</a> PLoS ONE. 8 (5), e61956 (2013).</li><li>Pattabiraman, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transcriptional+regulation+of+enhancers+active+in+protodomains+of+the+developing+cerebral+cortex.">Transcriptional regulation of enhancers active in protodomains of the developing cerebral cortex.</a> Neuron. 82 (5), 989-1003 (2014).</li></ol>

The authors declare that they have no competing financial interests.

El uso de GABAérgicas precursores interneuronas corticales de las eminencias ganglionares embrionarias (GES) para las terapias celulares basadas está mostrando promesa para muchas condiciones 12 -1 4. Se necesitan técnicas moleculares precisas para realizar un seguimiento, y expresar genes de interés en subgrupos específicos interneuronas. Aquí se proporciona un protocolo detallado para el etiquetado de las células embrionarias MGE con lentivirus antes del trasplante y mostrar cómo esta técnica puede...

GABAérgicas interneuronas corticales comprenden ~ 20-30% de las neuronas en la neocorteza de los mamíferos, mientras que el resto corresponde a excitatorios, neuronas glutamatérgicas principales. Las interneuronas son muy diversos en las propiedades electrofisiológicas, axón y dendritas y morfología sináptica objetivo 1, y los desequilibrios en el tono excitatorio / inhibitoria son la hipótesis de base de algunos fenotipos de los trastornos neuropsiquiátricos / neurológicos como el autismo, la esquizofrenia y la epilepsia 2. El objetivo general del protocolo descrito en este documento es proporcionar un medio para modificar genéticamente de manera eficiente GABAérgicas progenitores interneuronas corticales antes del trasplante para análisis in vivo. Interneuronas corticales GABAérgicas nacen en las eminencias ganglionares medial y caudal (MGE y CGE, respectivamente) 3,4, así como el área preóptica 5. Progenitores interneuronas corticales se someten a larga distancia migración tangencial seguidopor la migración radial para llegar a sus objetivos finales. Al llegar a sus destinos, estas interneuronas corticales deben integrar correctamente en la red neuronal existente, y cada subgrupo interneuron única contribuirán a los circuitos corticales de maneras específicas. Cuatro subgrupos principales se pueden distinguir por marcadores moleculares: somatostatina derivados de MGE (SST) + y parvalbúmina (PV) + subgrupos, y péptido derivado de CGE vasoactivo intestinal (VIP) + y + Reelin; SST - 6 subgrupos. Diferentes subgrupos interneuronas corticales nacen en diferentes tiempos durante el desarrollo embrionario en el MGE y CGE 7, 8. Estos y otros marcadores de interneuronas GABAérgicas corticales se han utilizado para generar líneas Cre-controlador específico para muchos de estos subgrupos 9-11. El trasplante de progenitores MGE ha surgido como una terapia basada en células potencial para el tratamiento de trastornos que pueden ser causados ​​por desequilibriosen excitación / inhibición de 12 - 24. Estos beneficios terapéuticos pueden deberse en parte a la capacidad única de los progenitores MGE (a dispersarse, diferenciar e integrar en un cerebro huésped), o potencialmente debido a que muchos peri-somáticas células fotovoltaicas inhibidora + se derivan de la MGE. MGE células también pueden ser rápida y eficientemente transducidas con lentivirus antes del trasplante 15, permitiendo que las células que se modifican genéticamente in vitro para estudiar in vivo. La razón fundamental para el desarrollo de este enfoque era superar obstáculos en el estudio GABAérgica desarrollo interneuronas corticales y maduración. En particular, MGE trasplante permitió a los investigadores a estudiar el desarrollo de las células mutantes in vivo, cuando el ratón mutante tendría de otro modo muerto en un punto de tiempo temprano. Por otra parte, mediante la introducción de genes de interés antes del trasplante, los efectos de genes específicos en un fenotipo mutante podrían evaluarse en un effmanera ciente. Aquí, ofrecemos un protocolo detallado para la transducción de células MGE con lentivirus previas al trasplante. Además, se muestra cómo esta técnica se puede adaptar para expresar un gen de interés en subgrupos específicos interneuronas de un grupo heterogéneo de precursores interneuronas corticales, utilizando una combinación de los lentivirus de expresión Cre-dependientes y disponibles líneas de ratones Cre-conductor. Por otra parte, este protocolo introduce técnicas y una plataforma para los investigadores de modificar genéticamente GABAérgicas precursores interneuronas corticales para estudios in vivo de una manera única. Una ventaja de esta técnica sobre otros enfoques actuales es que las células trasplantadas MGE se dispersarán lejos del sitio de la inyección. También, a diferencia de las inyecciones virales focales, después de las células MGE dispersan su morfología es más fácil de evaluar. Este enfoque se puede utilizar para estudiar el efecto de la introducción de genes de interés en las células de tipo salvaje o mutantes, la introducción de un tipo específico de célulareportero para evaluar la morfología, o potencialmente para estudiar el efecto de los alelos de la enfermedad in vivo.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Reagents and equipment for MGE cell transplantation</td>
		</tr>
		<tr>
			<td>1 ml syringe</td>
			<td>REF 309602</td>
			<td colspan="2">BD, Becton Dickinson and company</td>
		</tr>
		<tr>
			<td>301/2 gauge needle</td>
			<td>305106</td>
			<td colspan="2">BD, Becton Dickinson and company</td>
		</tr>
		<tr>
			<td>Precision bore to deliver 5 &#181;l (comes with plunger)</td>
			<td>5-000-1005</td>
			<td colspan="2">Drummond scientific company</td>
		</tr>
		<tr>
			<td>Parafilm</td>
			<td>PM-999</td>
			<td colspan="2">Polysciences, Inc.</td>
		</tr>
		<tr>
			<td>Stereo microscope with boomstand **</td>
			<td>MZ6</td>
			<td>Leica</td>
			<td></td>
		</tr>
		<tr>
			<td>Digital just for mice stereotaxic instrument **</td>
			<td>51725D</td>
			<td colspan="2">Stoelting company</td>
		</tr>
		<tr>
			<td>Single-axis oil hydraulic fine micromanipulator **</td>
			<td>MO-10</td>
			<td>Narishige</td>
			<td></td>
		</tr>
		<tr>
			<td>Diamond coated rotary beveler</td>
			<td>n.a.</td>
			<td colspan="2">made in house</td>
		</tr>
		<tr>
			<td>Needle pipette puller</td>
			<td>730</td>
			<td colspan="2">Kopf instruments</td>
		</tr>
		<tr>
			<td>Mineral oil</td>
			<td>n.a.</td>
			<td colspan="2">Any drug store or pharmacy</td>
		</tr>
		<tr>
			<td colspan="2">Any pipette and tips that can reliaby measure 1 &#181;l of volume</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td colspan="2">** These are the particular models we use, but many other setups should work</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Optional Reagents (for making Lentiviruses)</td>
		</tr>
		<tr>
			<td>25 mm, 0.45 &#181;m filter</td>
			<td>09-719B</td>
			<td colspan="2">Fisher Scientific</td>
		</tr>
		<tr>
			<td>Ultra-clear centrifuge tubes (25 x 89 mm)</td>
			<td>344058</td>
			<td colspan="2">Beckman Coulter&#174;</td>
		</tr>
		<tr>
			<td>Lipofectamine 2000 (1.5 ml size)</td>
			<td>11668019</td>
			<td colspan="2">Invitrogen</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Other commercially available supplies</td>
		</tr>
		<tr>
			<td>pMDLg/pRRE plasmid encoding gag/pol</td>
			<td>12251</td>
			<td>Addgene</td>
			<td></td>
		</tr>
		<tr>
			<td>pRSV-Rev plasmid encoding Rev</td>
			<td>12253</td>
			<td>Addgene</td>
			<td></td>
		</tr>
		<tr>
			<td>pMD2.G plasmid encoding VSVG</td>
			<td>12259</td>
			<td>Addgene</td>
			<td></td>
		</tr>
		<tr>
			<td>pAAV-Flex-GFP</td>
			<td>28304</td>
			<td>Addgene</td>
			<td></td>
		</tr>
	</tbody>
</table>

viral-mediated labeling and transplantation of medial ganglionic eminence (mge) cells for in vivo studies

GABAérgicas interneuronas corticales, derivados de la medial embrionario y eminencias ganglionares caudales (MGE y CGE), son funcional y morfológicamente diversa. Las incursiones se han hecho en la comprensión de las funciones de los distintos subgrupos de interneuronas corticales, sin embargo, todavía hay muchos mecanismos por resolver que pueden contribuir al desarrollo y maduración de los diferentes tipos de células GABAérgicas. Por otra parte, la señalización GABAérgica alterado puede contribuir a fenotipos de autismo, la esquizofrenia y la epilepsia. Líneas específicas Cre-controladores han comenzado a repartir las funciones de subgrupos interneuron únicas. A pesar de los avances en modelos de ratón, a menudo es difícil de estudiar de manera eficiente GABAérgicas progenitores interneuronas corticales con enfoques moleculares in vivo. Una técnica importante utilizada para estudiar la programación autónoma celular de estas células es el trasplante de células MGE en cortezas de acogida. Estas células trasplantadas migrar considerablemente, diferenciar, unand integrar funcionalmente. Además, las células MGE pueden ser transducidas eficientemente con lentivirus inmediatamente antes del trasplante, lo que permite una multitud de enfoques moleculares. A continuación te detallamos un protocolo para transducir eficazmente células MGE antes del trasplante para el análisis in vivo, utilizando líneas de Cre-controladores disponibles y vectores de expresión Cre-dependientes. Este enfoque es ventajoso, ya que combina la manipulación genética precisa con la capacidad de estas células para dispersar después del trasplante, lo que permite una mayor resolución específica de tipo celular in vivo.

Dado que las células de MGE tienen la capacidad única para migrar e integrar al ser implantadas en un neocórtex anfitrión 16, proporcionan un excelente sistema modelo para la manipulación genética antes de los estudios in vivo. En la presente memoria, se muestra cómo se puede aislar de tejido MGE de embriones E13.5 (Figuras 1 y 2), que luego pueden ser transducidas con lentivirus ya sea in vitro o en una manera rápida antes del trasplante para estudios in vivo.</...

Watch this Scientific Journal Video about Viral-mediated Labeling and Transplantation of Medial Ganglionic Eminence MGE Cells for In Vivo Studies at JoVE.com

Viral-mediated Labeling and Transplantation of Medial Ganglionic Eminence MGE Cells for In Vivo Studies

GABAérgicas progenitores interneuronas corticales se dispersan, desarrollar y sinápticamente integrar en una corteza de acogida después del trasplante. Estas células pueden ser fácilmente transducidas antes del trasplante para estudios in vivo de precursores GABAérgicas modificados genéticamente. Aquí, mostramos las técnicas de etiquetado virales para apuntar subgrupos interneuron específicos utilizando líneas de Cre existentes y reporteros Cre-dependientes.

Etiquetado y mediada por virus Trasplante de Medial ganglionar Eminencia (MGE) Las células para<em&gt; En Vivo</em&gt; Estudios

GABAergic cortical interneurons, derived from the embryonic medial and caudal ganglionic eminences (MGE and CGE), are functionally and morphologically ...

viral-mediated-labeling-transplantation-medial-ganglionic-eminence

Research

JoVE Journal

Developmental Biology

Viral-mediated Labeling and Transplantation of Medial Ganglionic Eminence (MGE) Cells for In Vivo Studies

11.4K vistas.  University of California San Francisco.  GABAérgicas progenitores interneuronas corticales se dispersan, desarrollar y sinápticamente integrar en una corteza de acogida después del trasplante. Estas células pueden ser fácilmente transducidas antes del trasplante para estudios in vivo de precursores GABAérgicas modificados genéticamente. Aquí, mostramos las técnicas de etiquetado virales para apuntar subgrupos interneuron específicos utilizando líneas de Cre existentes y reporteros Cre-depend...

Video: Viral-mediated Labeling and Transplantation of Medial Ganglionic Eminence MGE Cells for In Vivo Studies

Structure-function Studies in Mouse Embryonic Stem Cells Using Recombinase-mediated Cassette Exchange

Gene engineering in mouse embryos or embryonic stem cells (mESCs) allows for the study of the function of a given protein. Proteins are the workhorses of the cell and often consist of multiple functional domains, which can be influenced by posttranslational modifications. The depletion of the entire protein in conditional or constitutive knock-out (KO) mice does not take into account this functional diversity and regulation. An mESC line and a derived mouse model, in which a docking site for FLPe recombination-mediated cassette exchange (RMCE) was inserted within the ROSA26 (R26) locus, was previously reported. Here, we report on a structure-function approach that allows for molecular dissection of the different functionalities of a multidomain protein. To this end, RMCE-compatible mice must be crossed with KO mice and then RMCE-compatible KO mESCs must be isolated. Next, a panel of putative rescue constructs can be introduced into the R26 locus via RMCE targeting. The candidate rescue cDNAs can be easily inserted between RMCE sites of the targeting vector using recombination cloning. Next, KO mESCs are transfected with the targeting vector in combination with an FLPe recombinase expression plasmid. RMCE reactivates the promoter-less neomycin-resistance gene in the ROSA26 docking sites and allows for the selection of the correct targeting event. In this way, high targeting efficiencies close to 100% are obtained, allowing for insertion of multiple putative rescue constructs in a semi-high throughput manner. Finally, a multitude of R26-driven rescue constructs can be tested for their ability to rescue the phenotype that was observed in parental KO mESCs. We present a proof-of-principle structure-function study in p120 catenin (p120ctn) KO mESCs using endoderm differentiation in embryoid bodies (EBs) as the phenotypic readout. This approach enables the identification of important domains, putative downstream pathways, and disease-relevant point mutations that underlie KO phenotypes for a given protein.

Proteins often contain multiple domains that can exert different cellular functions. Gene knock-outs (KO) do not consider this functional diversity. Here, we report a recombination-mediated cassette exchange (RMCE)-based structure-function approach in KO embryonic stem cells that allows for the molecular dissection of various functional domains or variants of a protein.

Los estudios de estructura-función en las células madre embrionarias de ratón Usando mediada por recombinasa Cambio de Cassette

Gene engineering in mouse embryos or embryonic stem cells (mESCs) allows for the study of the function of a given protein. Proteins are the workhorses of ...

Investigación

Biología del Desarrollo

A Novel Mammary Fat Pad Transplantation Technique to Visualize the Vessel Generation of Vascular Endothelial Stem Cells

Endothelial cells (ECs) are the fundamental building blocks of the vascular architecture and mediate vascular growth and remodeling to ensure proper vessel development and homeostasis. However, studies on endothelial lineage hierarchy remain elusive due to the lack of tools to gain access as well as to directly evaluate their behavior in vivo. To address this shortcoming, a new tissue model to study angiogenesis using the mammary fat pad has been developed. The mammary gland develops mostly in the postnatal stages, including puberty and pregnancy, during which robust epithelium proliferation is accompanied by extensive vascular remodeling. Mammary fat pads provide space, matrix, and rich angiogenic stimuli from the growing mammary epithelium. Furthermore, mammary fat pads are located outside the peritoneal cavity, making them an easily accessible grafting site for assessing the angiogenic potential of exogenous cells. This work also describes an efficient tracing approach using fluorescent reporter mice to specifically label the targeted population of vascular endothelial stem cells (VESCs) in vivo. This lineage tracing method, coupled with subsequent tissue whole-mount microscopy, enable the direct visualization of targeted cells and their descendants, through which the proliferation capability can be quantified and the differentiation commitment can be fate-mapped. Using these methods, a population of bipotent protein C receptor (Procr) expressing VESCs has recently been identified in multiple vascular systems. Procr+ VESCs, giving rise to both new ECs and pericytes, actively contribute to angiogenesis during development, homeostasis, and injury repair. Overall, this manuscript describes a new mammary fat pad transplantation and in vivo lineage tracing techniques that can be used to evaluate the stem cell properties of VESCs.

This work demonstrates a novel approach to assess the proliferation, differentiation, and vessel-forming potential of vascular endothelial stem cells (VESCs) through mammary fat pad transplantation followed by whole-mount tissue preparation for microscopic observation. A lineage tracing strategy to investigate the behavior of VESCs in vivo is also presented.

Una nueva técnica de trasplante de grasa mamaria para visualizar la generación de vasos de células madre endoteliales vasculares

Endothelial cells (ECs) are the fundamental building blocks of the vascular architecture and mediate vascular growth and remodeling to ensure proper ...

Horizontal Whole Mount: A Novel Processing and Imaging Protocol for Thick, Three-dimensional Tissue Cross-sections of Skin

Processing a tissue of interest to generate a microscopic image that supports a scientific argument can be challenging. The acquisition of high-quality microscopic images is not entirely dependent upon the quality of the microscope, but also upon the methods of tissue processing, which often involve multiple critical actions or steps. Furthermore, mesenchymal cell types in the skin and other tissues represent a new challenge for tissue preparation and imaging. Here, we present a complete process, from tissue harvest to microscopy. Our technique, called &#34;horizontal whole mount,&#34; is one that novices can quickly become proficient in and that allows for antigen preservation and detection in 60-300 &#181;m-thick sections cut with a cryostat. Sections of this thickness provide enhanced visualization of tissue microarchitecture in a three-dimensional environment. In addition, the protocol preserves mesenchymal cells in a manner that enhances image quality when compared to standard cryostat or paraffin sections, thereby increasing the efficacy and reliability of immunostaining. We believe that this protocol will benefit all laboratories that visualize skin, and possibly other tissues and organs.

This work presents a novel processing and imaging protocol for thick, three-dimensional tissue cross-section analysis that enables the full exploitation of confocal imaging modalities. This protocol preserves antigenicity and represents a robust system to analyze skin histology and potentially other tissue types.

Montaje entero horizontal: un nuevo protocolo de procesamiento e imágenes para tejidos gruesos y tridimensionales Secciones transversales de la piel

Processing a tissue of interest to generate a microscopic image that supports a scientific argument can be challenging. The acquisition of high-quality ...

Immuno-fluorescent Labeling of Microtubules and Centrosomal Proteins in Ex Vivo Intestinal Tissue and 3D In Vitro Intestinal Organoids

The advent of 3D in vitro organoids that mimic the in vivo tissue architecture and morphogenesis has greatly advanced the ability to study key biological questions in cell and developmental biology. In addition, organoids together with recent technical advances in gene editing and viral gene delivery promises to advance medical research and development of new drugs for treatment of diseases. Organoids grown in vitro in basement matrix provide powerful model systems for studying the behavior and function of various proteins and are well suited for live-imaging of fluorescent-tagged proteins. However, establishing the expression and localization of the endogenous proteins in ex vivo tissue and in in vitro organoids is important to verify the behavior of the tagged proteins. To this end we have developed and modified tissue isolation, fixation, and immuno-labeling protocols for localization of microtubules, centrosomal, and associated proteins in ex vivo intestinal tissue and in in vitro intestinal organoids. The aim was for the fixative to preserve the 3D architecture of the organoids/tissue while also preserving antibody antigenicity and enabling good penetration and clearance of fixative and antibodies. Exposure to cold depolymerizes all but stable microtubules and this was a key factor when modifying the various protocols. We found that increasing the ethylenediaminetetraacetic acid (EDTA) concentration from 3 mM to 30 mM gave efficient detachment of villi and crypts in the small intestine while 3 mM EDTA was sufficient for colonic crypts. The developed formaldehyde/methanol fixation protocol gave very good structural preservation while also preserving antigenicity for effective labeling of microtubules, actin, and the end-binding (EB) proteins. It also worked for the centrosomal protein ninein although the methanol protocol worked more consistently. We further established that fixation and immuno-labeling of microtubules and associated proteins could be achieved with organoids isolated from or remaining within the basement matrix.

Immuno-fluorescent Labeling of Microtubules and Centrosomal Proteins in Ex Vivo Intestinal Tissue and 3D In Vitro Intestinal Organoids

We present protocols for isolation of intestinal 3D structures from in vivo tissue and in vitro basement matrix embedded organoids, and detail different fixation and staining protocols optimized for immuno-labeling of microtubule, centrosomal, and junctional proteins as well as cell markers including the stem cell protein Lgr5.

Inmuno-fluorescente etiquetado de microtúbulos y proteínas centrosómicas en tejido Intestinal Ex Vivo y 3D In Vitro Intestinal organitas

The advent of 3D in vitro organoids that mimic the in vivo tissue architecture and morphogenesis has greatly advanced the ability to study key biological ...

Single-cell Photoconversion in Living Intact Zebrafish

Animal and plant tissue is composed of distinct populations of cells. These cells interact over time to build and maintain the tissue and can cause disease when disrupted. Scientists have developed clever techniques to investigate characteristics and natural dynamics of these cells within intact tissue by expressing fluorescent proteins in subsets of cells. However, at times, experiments require more selected visualization of cells within the tissue, sometimes at the single-cell or population-of-cells manner. To achieve this and visualize single cells within a population of cells, scientists have utilized single-cell photoconversion of fluorescent proteins. To demonstrate this technique, we show here how to direct UV light to an Eos-expressing cell of interest in an intact, living zebrafish. We then image those photoconverted Eos+ cells 24 h later to determine how they changed in the tissue. We describe two techniques: single cell photoconversion and photoconversions of populations of cell. These techniques can be used to visualize cell-cell interactions, cell-fate and differentiation, and cell migrations, making it a technique that is applicable in numerous biological questions.

Here, we present a protocol to show how cell photoconversion is achieved through UV exposure to specific areas expressing the fluorescent protein, Eos, in living animals.

Sola célula Photoconversion en pez cebra intacto de la vida

Animal and plant tissue is composed of distinct populations of cells. These cells interact over time to build and maintain the tissue and can cause ...

Intravenous and Intra-amniotic In Utero Transplantation in the Murine Model

In utero transplantation (IUT) is a unique and versatile mode of therapy that can be used to introduce stem cells, viral vectors, or any other substances early in the gestation. The rationale behind IUT for therapeutic purposes is based on the small size of the fetus, the fetal immunologic immaturity, the accessibility and proliferative nature of the fetal stem or progenitor cells, and the potential to treat a disease or the onset of symptoms prior to birth. Taking advantage of these normal developmental properties of the fetus, the delivery of hematopoietic stem cells (HSC) via an IUT has the potential to treat congenital hematologic disorders such as sickle cell disease, without the required myeloablative or immunosuppressive conditioning required for postnatal HSC transplants. Similarly, the accessibility of progenitor cells in multiple organs during development potentially allows for a more efficient targeting of stem/progenitor cells following an IUT of viral vectors for gene therapy or genome editing. Additionally, IUT can be used to study normal developmental processes including, but not limited to, the development of immunologic tolerance. The murine model provides a valuable and affordable means to understanding the potential and limitations of IUT prior to pre-clinical large animal studies and an eventual clinical application. Here, we describe a protocol for performing an IUT in the murine fetus through intravenous and intra-amniotic routes. This protocol has been used successfully to elucidate the necessary conditions and mechanisms behind in utero hematopoietic stem cell transplantation, tolerance induction, and in utero gene therapy.

Intravenous and Intra-amniotic In Utero Transplantation in the Murine Model

We describe a protocol for performing an in utero transplantation (IUT) through intravenous and intra-amniotic routes of injection in the murine model. This protocol can be used to introduce cells, viral vectors, and other substances into the unique immune-tolerant fetal environment.

Intravenosa y Intra-amniótico en el útero el trasplante en el modelo murino

In utero transplantation (IUT) is a unique and versatile mode of therapy that can be used to introduce stem cells, viral vectors, or any other substances ...

In Vitro Generation of Somite Derivatives from Human Induced Pluripotent Stem Cells

In response to signals such as WNTs, bone morphogenetic proteins (BMPs), and sonic hedgehog (SHH) secreted from surrounding tissues, somites (SMs) give rise to multiple cell types, including the myotome (MYO), sclerotome (SCL), dermatome (D), and syndetome (SYN), which in turn develop into skeletal muscle, axial skeleton, dorsal dermis, and axial tendon/ligament, respectively. Therefore, the generation of SMs and their derivatives from human induced pluripotent stem cells (iPSCs) is critical to obtain pluripotent stem cells (PSCs) for application in regenerative medicine and for disease research in the field of orthopedic surgery. Although the induction protocols for MYO and SCL from PSCs have been previously reported by several researchers, no study has yet demonstrated the induction of SYN and D from iPSCs. Therefore, efficient induction of fully competent SMs remains a major challenge. Here, we recapitulate human SM patterning with human iPSCs in vitro by mimicking the signaling environment during chick/mouse SM development, and report on methods of systematic induction of SM derivatives (MYO, SCL, D, and SYN) from human iPSCs under chemically defined conditions through the presomitic mesoderm (PSM) and SM states. Knowledge regarding chick/mouse&#160;SM development was successfully applied to the induction of SMs with human iPSCs. This method could be a novel tool for studying human somitogenesis and patterning without the use of embryos and for cell-based therapy and disease modeling.

We present here a protocol for the differentiation of human induced pluripotent stem cells into each somite derivative (myotome, sclerotome, dermatome, and syndetome) in chemically defined conditions, which has applications in future disease modeling and cell-based therapies in orthopedic surgery.

En la generación de Vitro del Somite derivados humanos inducida por células madre pluripotentes

In response to signals such as WNTs, bone morphogenetic proteins (BMPs), and sonic hedgehog (SHH) secreted from surrounding tissues, somites (SMs) give ...

Controlled Cortical Impact Model of Mouse Brain Injury with Therapeutic Transplantation of Human Induced Pluripotent Stem Cell-Derived Neural Cells

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Disease pathology due to TBI progresses from the primary mechanical insult to secondary injury processes, including apoptosis and inflammation. Animal modeling has been valuable in the search to unravel injury mechanisms and evaluate potential neuroprotective therapies. This protocol describes the controlled cortical impact (CCI) model of focal, open-head TBI. Specifically, parameters for producing a mild unilateral cortical injury are described. Behavioral consequences of CCI are analyzed using the adhesive tape removal test of bilateral sensorimotor integration. Regarding experimental therapy for TBI pathology, this protocol also illustrates a process for transplanting cultured cells into the brain. Neural cell cultures derived from human induced pluripotent stem cells (hiPSCs) were chosen for their potential to show superior functional restoration in human TBI patients. Chronic survival of hiPSCs in the host mouse brain tissue is detected using a modified DAB immunohistochemical process.

This protocol demonstrates methodologies for a mouse model of open-skull traumatic brain injury and transplantation of cultured human induced pluripotent stem cell-derived cells into the injury site. Behavioral and histologic tests of outcomes from these procedures are also described in brief.

Modelo de impacto cortical controlado de lesión cerebral de ratón con trasplante terapéutico de células neuronales derivadas de células madre pluripotentes inducidas por el hombre

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Disease pathology due to TBI progresses from the primary mechanical ...

Generation of Induced Neural Stem Cells from Peripheral Mononuclear Cells and Differentiation Toward Dopaminergic Neuron Precursors for Transplantation Studies

Parkinson&#39;s disease (PD) is caused by degeneration of dopaminergic (DA) neurons at the substantia nigra pars compacta (SNpc) in the ventral mesencephalon (VM). Cell replacement therapy holds great promise for treatment of PD. Recently, induced neural stem cells (iNSCs) have emerged as a potential candidate for cell replacement therapy due to the reduced risk of tumor formation and the plasticity to give rise to region-specific neurons and glia. iNSCs can be reprogrammed from autologous somatic cellular sources, such as fibroblasts, peripheral blood mononuclear cells (PBMNCs) and various other types of cells. Compared with other types of somatic cells, PBMNCs are an appealing starter cell type because of the ease to access and expand in culture. Sendai virus (SeV), an RNA non-integrative virus, encoding reprogramming factors including human OCT3/4, SOX2, KLF4 and c-MYC, has a negative-sense, single-stranded, non-segmented genome that does not integrate into host genome, but only replicates in the cytoplasm of infected cells, offering an efficient and safe vehicle for reprogramming. In this study, we describe a protocol in which iNSCs are obtained by reprogramming PBMNCs, and differentiated into specialized VM DA neurons by a two-stage method. Then DA precursors are transplanted into unilaterally 6-hyroxydopamine (6-OHDA)-lesioned PD mouse models to evaluate the safety and efficacy for treatment of PD. This method provides a platform to investigate the functions and therapeutic effects of patient-specific DA neural cells in vitro and in vivo.

The protocol presents the reprogramming of peripheral blood mononuclear cells to induce neural stem cells by Sendai virus infection, differentiation of iNSCs into dopaminergic neurons, transplantation of DA precursors into the unilaterally-lesioned Parkinson&#39;s disease mouse models, and evaluation of the safety and efficacy of iNSC-derived DA precursors for PD treatment.

Generación de células madre neuronales inducidas a partir de células mononucleares periféricas y diferenciación hacia precursores de neuronas dopaminérgicas para estudios de trasplante

Parkinson&#39;s disease (PD) is caused by degeneration of dopaminergic (DA) neurons at the substantia nigra pars compacta (SNpc) in the ventral ...

Isolation of Rat Adipose Tissue Mesenchymal Stem Cells for Differentiation into Insulin-producing Cells

Mesenchymal stem cells (MSCs)-especially those isolated from adipose tissue (Ad-MSCs)-have gained special attention as a renewable, abundant source of stem cells that does not pose any ethical concerns. However, current methods to isolate Ad-MSCs are not standardized and employ complicated protocols that require special equipment. We isolated Ad-MSCs from the epididymal fat of Sprague-Dawley rats using a simple, reproducible method. The isolated Ad-MSCs usually appear within 3 days post isolation, as adherent cells display fibroblastic morphology. Those cells reach 80% confluency within 1 week of isolation. Afterward, at passage 3-5 (P3-5), a full characterization was carried out for the isolated Ad-MSCs by immunophenotyping for characteristic MSC cluster of differentiation (CD) surface markers such as CD90, CD73, and CD105, as well as inducing differentiation of these cells down the osteogenic, adipogenic, and chondrogenic lineages. This, in turn, implies the multipotency of the isolated cells. Furthermore, we induced the differentiation of the isolated Ad-MSCs toward the insulin-producing cells (IPCs) lineage via a simple, relatively short protocol by incorporating high glucose Dulbecco&#39;s modified Eagle medium (HG-DMEM), &#946;-mercaptoethanol, nicotinamide, and exendin-4. IPCs differentiation was genetically assessed, firstly, via measuring the expression levels of specific &#946;-cell markers such as MafA, NKX6.1, Pdx-1, and Ins1, as well as dithizone staining for the generated IPCs. Secondly, the assessment was also carried out functionally by a glucose-stimulated insulin secretion (GSIS) assay. In conclusion, Ad-MSCs can be easily isolated, exhibiting all MSC characterization criteria, and they can indeed provide an abundant, renewable source of IPCs in the lab for diabetes research.

Adipose tissue-derived mesenchymal stem cells (Ad-MSCs) can be a potential source of MSCs that differentiate into insulin-producing cells (IPCs). In this protocol, we provide detailed steps for the isolation and characterization of rat epididymal Ad-MSCs, followed by a simple, short protocol for the generation of IPCs from the same rat Ad-MSCs.

Aislamiento de células madre mesenquimales del tejido adiposo de rata para la diferenciación en células productoras de insulina

Mesenchymal stem cells (MSCs)-especially those isolated from adipose tissue (Ad-MSCs)-have gained special attention as a renewable, abundant source of ...