Damos las gracias a C. Park por leer el manuscrito. Este trabajo fue apoyado por el NIAMS en Número Award y un Premio K01AR061434 Leukemia &amp; Lymphoma Society Fellowship (5127-09) para DP y subvenciones de los Institutos Nacionales de Salud a CPL y DTS El contenido es de exclusiva responsabilidad de sus autores y no representan necesariamente las opiniones oficiales de los Institutos Nacionales de Salud.

1. Los ratones y precondicionamiento Nota: Todos los ratones se mantuvieron en condiciones libres de patógenos y todos los protocolos fueron aprobados por el Cuidado de Animales y el empleo Comisión Institucional (IACUC) en el Hospital General de Massachusetts. Toda la cirugía debe realizarse en condiciones estériles utilizando material estéril en autoclave. Mx1-Cre 15, Rosa26-loxP-stop-loxP-EYFP (Rosa-YFP), y Rosa26-loxP-stop-loxP-tdTomato (Rosa-Tomate), fueron compraron de Jackson Laboratories. ratones osteocalcina-GFP fueron proporcionados por el Dr. Henry Kronenberg. Para el análisis cuantitativo de OSPC migración y proliferación in vivo, se utilizaron + (solo color-reportero) ratones Mx1-Cre + Rosa-YFP. Para un seguimiento más detallado de su diferenciación en osteoblastos osteocalcina + maduros, utilizamos trigénico Mx1-Cre + Rosa-Tomate + OCN-GFP +ratones. <ol><li> Para marcar las células Mx1 + in vivo, preparar ácido poliinosínico-policitidílico (PIPC, 2,5 mg / ml) en solución de PBS estéril e inyectar 200 l por 20 g de Mx1-Cre + reportero de ratón por vía intraperitoneal una vez cada dos días durante 10 días. </li><li> Para eliminar las células Mx1 + hematopoyéticas residentes, irradiar ratones con una sola dosis de 9,5 Gy. Después de 24 horas de irradiación, las células de tipo salvaje de trasplante de médula ósea (1x10 6 células / ratón) por vía intravenosa 16. Nota: Puesto que las células Mx1-inducibles incluyen las células hematopoyéticas y los osteoclastos hematopoyéticos derivados, la eliminación de las células hematopoyéticas + Mx1 mejora la calidad de imagen y cuantificación de células osteogénicas + Mx1. </li><li> Después de trasplante de médula ósea, para observar a los animales cuatro a seis semanas con el fin de lograr una repoblación con éxito de células de donantes de médula. </li></ol> 2. Moutilizar Preparación <ol><li> Anestesie ratón mediante inyección intraperitoneal de 50 l de ketamina / xilazina (100 mg / kg, xilazina 12 mg / kg de peso corporal) mediante un procedimiento aprobado por la IACUC. Nota: La duración del efecto puede ser prorrogado por una dosis adicional de ketamina / xilazina. </li><li> Determine si el ratón está totalmente anestesiado por la falta de respuesta a los pies y / o pellizcos de cola. (Opcional) Cuando se anestesia el ratón, asegurar una máscara de gas isoflurano sobre la nariz con cinta adhesiva. Ajuste el nivel de isoflurano para asegurar que el animal está completamente sedado. </li><li> Corte el pelo del cuero cabelludo utilizando un condensador de ajuste eléctrico o tijera pequeña. Retire los fragmentos de cabello y esterilizar la piel expuesta con un 70% algodón con alcohol. Aplique el gel lacrimógenos para evitar la deshidratación de la córnea. </li></ol> 3. Lesiones Microfractura <ol><li> Después de asegurarse de que el animal está completamente sedado, hacer una sola incisión en forma de L inversa para abrir la piel del cuero cabelludo. En pocas palabras, hacer una primera incisión transversal (menos de 1 cm) InicioÌón de una oreja a otra oreja. Gire ~ 60 ° y continuar incisión hacia la nariz hasta ~ 2-3 mm de distancia de la nariz. Nota: Esta incisión minimiza la formación de tejidos de la cicatriz por encima del área a explorar. </li><li> Separe los colgajos de piel tirando hacia los lados con unas pinzas. Ambos huesos frontales y la intersección de las suturas coronal y sagital deben ser claramente expuestos. </li><li> Limpie la superficie abierta por el lavado con PBS estéril y de limpieza suave con gasa o algodón hisopos estériles hasta que se eliminen todos los pelos residuales. </li><li> Para generar microfracturas en la bóveda craneal, sostenga la cabeza del ratón con una mano y una aguja de 30 G con la otra mano. Hacer un micro-punción (~ 0,2 mm de diámetro de la herida con &lt;1 mm de profundidad) en el hueso frontal izquierdo, cerca de la intersección de las suturas coronal y sagital, insertando la punta de una aguja de 30 G con una presión suave y movimiento de torsión. Precaución: Es fundamental para evitar que la aguja penetre en el cerebro, lo que minimiza bleeding y el daño tisular. </li><li> Cambie a una aguja más grande (20 o 25 G) y ensanchar el orificio de punción girando la aguja (~ 0,5 mm de diámetro). </li><li> Repita el paso 3.3 a 3.5 para generar segunda punción en el hueso frontal contralateral. </li><li> Limpie hacia fuera los puntos lesionados por goteo continuo de PBS hasta que el sangrado se detenga. Nota: El sangrado en los sitios de fractura va a interferir con la imagen apropiada e inducir la formación de cicatrices. </li><li> Aplique una gota de solución salina fisiológica estéril o 2% de Methocel en el cráneo para evitar que se sequen. Nota: No permita que la superficie del cráneo se seque, lo que reducirá la claridad de la imagen. Es importante usar una cantidad suficiente de gel o solución salina para cubrir el área. </li></ol> 4. Imaging intravital <ol><li> (Opcional) Antes de formación de imágenes, algunos ratones se les inyecta un colorante vascular para visualizar los vasos sanguíneos. Inyectar retro-orbital con 20 l de Qtracker no dirigido 705 (2 M solución en 50 mM de tampón de borato) diluido en 80 ml de PBS. Utilice una jeringa de insulina para minimizar el desperdicio de reactivos. Si la señal no es lo suficientemente brillante, podrían ser necesarias cantidades adicionales. </li><li> Encienda el escáner. Nota: Un escáner láser basado en polígonos permite la adquisición simultánea de múltiples canales de imagen a una velocidad de vídeo (30 fotogramas por segundo). Escaneo tasa video es muy importante para la formación de imágenes de animales vivos. </li><li> Encienda el láser multi-fotón (femto-segundos de titanio: zafiro láser). Establecer la longitud de onda a 880 nm y ajustar la potencia para la segunda generación de armónicos de formación de imágenes (440 nm) del hueso. Por las buenas prácticas agrarias y tdTomato excitación, encienda el 491 nm y 561 nm láser de estado sólido. </li><li> Encienda el PMT (tubo fotomultiplicador) detectores para cada señal (a ± filtro de paso de banda 435 20 nm para generación de segundo armónico, un ± filtro de paso de banda 528 19 nm para GFP, y 590 ± 20 para tdTomato.) (Opcional) Utilice un 638 nm láser de helio-neón y un PMT con un ± filtro paso banda 695 27,5 nm para detectar Qtracker 705 de señal. </li><li> Placcorreo del animal en una platina del microscopio motorizado XYZ-eje. Mantenga el ratón en la posición más cómoda con una almohadilla eléctrica para ayudar a mantener la temperatura del cuerpo (lo que reduce el riesgo de pérdida de animales). Use cinta adhesiva para sujetar el ratón para minimizar el movimiento durante la exploración y para mantener el área de la imagen lo más horizontal posible. </li><li> Aplique una gota de gel caliente metilcelulosa 2% o solución salina fisiológica en el cráneo para evitar que se sequen. Ponga una cubierta de vidrio en el área de imagen. Utilice un objetivo de bajo aumento (30x objetivo de inmersión en agua con 0,9 NA) para explorar el calvaria. </li><li> Utilizando el controlador XYZ-eje, encontrar la superficie de la bóveda craneal mediante la detección de la señal de GAA de los huesos e identificar una ubicación de punto de interés fundamental, tales como la intersección entre las suturas sagital y coronal suturas. Adquirir una imagen y registrar las coordenadas XYZ. </li><li> Continuar para buscar la ubicación de la lesión mediante la observación de las señales de los grupos de autoayuda y de fluorescencia. </li><li> Cuando los sitios de lesión o de la región of interés se encuentran, adquirir una imagen de la mejor plano focal que contiene las señales de fluorescencia de GAA y de las células de interés. Guardar coordenadas XYZ y la distancia a la intersección de las suturas coronal y sagital para definir su ubicación con precisión las próximas rondas de formación de imágenes. </li><li> Para recoger las estructuras celulares y de los huesos en 3D de una lesión de fractura, grabar imágenes de Z-pilas (2-5 micras) con intervalos de ~ 100 m de profundidad desde la superficie del hueso endosteal. Después de la finalización de la formación de imágenes de un lado de la lesión, repetir el proceso de formación de imágenes para los sitios de lesión próximos. </li></ol> Procedimientos 5. Publicar Operación <ol><li> Después de formación de imágenes, enjuague sitio de formación de imágenes con solución salina estéril para eliminar el gel de metilcelulosa del cráneo. El uso de un bastoncillo de algodón estéril, aplicar una pequeña cantidad de pomada antibiótica triple en la superficie. Cubra los colgajos de piel y volver a cerrar el cuero cabelludo mediante sutura quirúrgica. Esto se puede hacer con un hilo de sutura hipoalergénico (poliglactina absorbible dotura) y 5-0 tamaño de la aguja de sutura. Precaución: Una buena técnica de sutura reduce al mínimo la formación de cicatrices. </li><li> Tratar a todos los animales con inyección IP de 0,05-0,1 mg / kg de buprenorfina cada 12 horas durante 48 horas después de la cirugía. Mantener a los animales en una cámara de recuperación tibia hasta que recobren el conocimiento suficiente. Después de 3 a 5 días, abrir de nuevo la sutura y repetir los pasos intravital de imágenes para realizar el seguimiento del cambio celular durante la curación de la fractura. </li></ol>

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Los autores declaran que no tienen intereses en competencia financieros.

La regulación de las células madre del esqueleto puede ser de gran importancia para definir los mejores métodos para lograr la regeneración ósea. Imágenes cuantitativa y secuencial a nivel celular ha sido técnicamente difícil. Aunque el modelo de fractura de los huesos largos del ratón ha sido ampliamente utilizado y adecuado para estudios biomecánicos 17, su ubicación de tejido profundo, el tamaño de la fractura desigual, daño de tejidos blandos, y la aplicación de fijadores de estabilización ...

Enfermedades óseas degenerativas y la pérdida ósea relacionada con la edad que conduce a un alto riesgo de fractura por osteoporosis se ha convertido en un reto importante en la salud pública 1. Mantenimiento óseo está controlado por los osteoblastos forman el hueso y los osteoclastos de resorción ósea. Los defectos de las células formadoras de hueso son una causa principal de la pérdida ósea relacionada con la edad y las enfermedades óseas degenerativas 2,3. Si bien una amplia investigación se ha centrado en la mejora de la curación de la fractura, el descubrimiento de fármacos fiables para curar enfermedades degenerativas del hueso y para revertir la debilidad de las fracturas osteoporóticas sigue siendo un problema importante. Por lo tanto, el estudio de la fuente de células formadoras de hueso y sus mecanismos de control en la regeneración ósea y la reparación proporciona una nueva visión para mejorar la regeneración del esqueleto y revertir enfermedades de pérdida ósea. La existencia de células mesenquimales multipotentes en la médula ósea se ha propuesto sobre la base de la identificación de poblaciones clonogénicas que podía diferenteIATE en osteogénico, linajes adipogénicos y condrogénicas ex vivo 4. Recientemente, varios estudios han informado de que las células madre del esqueleto / mesenquimales (SSC / MSC) son una fuente natural de los osteoblastos y son fundamentales para la renovación ósea, remodelación y reparación de la fractura 5,6 . Además, nuestro estudio de trazado de linaje revelado que los osteoblastos maduros tienen una vida media corta inesperadamente (~ 60 días) y se reponen continuamente por sus células madre / progenitoras en ambas condiciones homeostáticas y reparación de fracturas normales 6. Sin embargo, la identidad in vivo de células madre y cómo tales células reaccionan a la fractura lesión y suministrar las células formadoras de hueso no son claras. Por lo tanto, es importante desarrollar un método que es capaz de analizar la migración, proliferación y diferenciación de las ESC endógenos / MSC en bajo circunstancias fisiológicas. Reparación de la fractura es un proceso de múltiples celular y dinámica regulada por una matriz de complejocitocinas y factores de crecimiento 7. El enfoque más popular para los estudios de fractura es el uso de un modelo animal con la fractura de los huesos largos y para analizar los huesos por seccionamiento hueso y técnicas de inmunofluorescencia 8-10. Este proceso de reparación puede ser supervisada por múltiples técnicas de imagen incluyendo micro-CT 11, la fluorescencia del infrarrojo cercano 12, y de formación de imágenes de quimioluminiscencia 13. Sin embargo, cada técnica tiene ciertas limitaciones y no ha habido manera efectiva de controlar la función ESC / MSC a nivel celular in vivo. Recientemente, confocal / de dos fotones microscopía intravital se ha desarrollado y utilizado para detectar células de cáncer trasplantado y las células madre hematopoyéticas en el contexto de su microambiente de la médula ósea, incluso con una resolución de una sola célula en animales vivos 14. Mediante la combinación de esta tecnología con una serie de modelos de rastreo de linaje, hemos sido capaces de definir que las células madre osteogénico / progenitoras se pueden marcar genéticamente por ac transitoriavación de la resistencia myxovirus -1 (Mx1) promotor y progenitores inducida Mx1-puede mantener la mayoría de los osteoblastos maduros con el tiempo, pero no participar en la generación de condrocitos en el ratón adulto 6. Además, hemos demostrado que OspC etiquetados-MX1 suministran la mayoría de los nuevos osteoblastos en la curación de fracturas 6. En este caso, el uso de modelos de seguimiento de osteo-linaje y microscopía intravital, se proporciona un protocolo para definir la cinética in vivo de + células madre / progenitoras osteogénicas Mx1 en la reparación de fracturas. Este protocolo ofrece imágenes secuenciales para seguir la reubicación de osteogénicas madre / progenitoras en los sitios de fractura y la medición cuantitativa de expansión osteoprogenitoras en el proceso de reparación temprana. Este enfoque puede ser útil en varios contextos, incluyendo la evaluación de candidatos terapéuticos para mejorar la reparación del hueso.

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			<td height="63" style="height:63px;width:216px;">C57BL/6J (H-2b)</td>
			<td style="width:140px;">Jackson Laboratories (Bar Harbor, ME)</td>
			<td style="width:195px;">000664</td>
			<td style="width:279px;"></td>
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			<td height="42" style="height:42px;width:216px;">Ketamine Hydrochloride Injection</td>
			<td style="width:140px;">Bionichepharma</td>
			<td style="width:195px;">67457-001-10</td>
			<td>&#160;Vial size: 10 ml (50 mg/ml)</td>
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			<td height="21" style="height:21px;width:216px;">Xylazine Sterile Solution</td>
			<td style="width:140px;">Lloyd Inc.</td>
			<td style="width:195px;">NADA# 139-236</td>
			<td></td>
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			<td height="21" style="height:21px;width:216px;">Buprenorphine Hl</td>
			<td style="width:140px;">BEDFORD LAB</td>
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			<td height="21" style="height:21px;width:216px;">DPBS, 1X</td>
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			<td style="width:195px;">21-031-CV</td>
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			<td height="42" style="height:42px;width:216px;">Alcohol Prep Pads (70% Isopropyl alcohol)</td>
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			<td style="width:195px;">5110</td>
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			<td height="21" style="height:21px;width:216px;">Fine Surgical Scissor</td>
			<td style="width:140px;">F.S.T</td>
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			<td height="21" style="height:21px;width:216px;">Extra fine Forceps</td>
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			<td height="42" style="height:42px;width:216px;">Qtracker 705 non-targeted quantum dot</td>
			<td style="width:140px;">Invitrogen</td>
			<td style="width:195px;">Q21061</td>
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			<td height="21" style="height:21px;width:216px;">Methocel 2%</td>
			<td style="width:140px;">OmmiVision</td>
			<td style="width:195px;"></td>
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		<tr height="42">
			<td height="42" style="height:42px;width:216px;">pIpC (Polyinosinic-polycytidylic acid)&#160;&#160;</td>
			<td style="width:140px;">Sigma</td>
			<td style="width:195px;">P0913-50MG</td>
			<td>100 &#956;l (2.5 mg/ml in PBS) for 10 g of mouse</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Mai Tai Tunable Ultrafast Lasers</td>
			<td style="width:140px;">Spectra Physics</td>
			<td style="width:195px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Dual Calypso 491 + 532 nm DPSS laser</td>
			<td style="width:140px;">Cobolt AB</td>
			<td style="width:195px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Radius-635 HeNe laser</td>
			<td style="width:140px;">Coherent</td>
			<td style="width:195px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

sequential in vivo imaging of osteogenic stem/progenitor cells during fracture repair

Hueso vuelca continuamente y es muy regenerativa tras una lesión. Células madre / progenitoras osteogénicas larga han sido la hipótesis de existir, sino con demostración in vivo de tales células sólo recientemente se ha alcanzado. En este caso, se proporcionan en las técnicas de imagen in vivo para investigar el papel de las células madre / progenitoras osteogénicas endógenos (OspC) y su progenie en la reparación ósea. El uso de células osteo-linaje modelos de rastreo y de imagen intravital de microfracturas inducidas en calota, OspC se puede observar directamente durante los primeros días después de la lesión, en la que se producen los eventos críticos en el proceso de reparación temprana. Lesiones sitios se pueden obtener imágenes de forma secuencial revela que OspC reubicar a la lesión, aumenta en número y se diferencian en osteoblastos que forman los huesos. Estos métodos ofrecen un medio para investigar el papel de los reguladores moleculares de células madre-intrínsecos y extrínsecos para la regeneración ósea y la reparación.

<html> El modelo de fractura de huesos largos estabilizado ha sido muy popular en los estudios de fractura. Sin embargo, los modelos de fractura grandes hueso largo o causar daño tisular múltiple y, por lo tanto, tienen una limitación en la medición cuantitativa de la función de las células óseas. Hemos desarrollado una lesión mínimamente invasiva (menos de 1 mm de diámetro con invasión mínima o ninguna en la duramadre) en huesos frontales de calota con la perforación de la aguja (figuras 1A-1C).</st...

Watch this Scientific Journal Video about Sequential In vivo Imaging of Osteogenic Stem/Progenitor Cells During Fracture Repair at JoVE.com

Sequential In vivo Imaging of Osteogenic Stem/Progenitor Cells During Fracture Repair

La medición cuantitativa de la función de progenitores de médula en la curación de la fractura requiere alta resolución tecnología de imágenes en serie. Aquí, se proporcionan protocolos para el uso de microscopía intravital y seguimiento osteo-linaje secuencialmente imagen y cuantificar la migración, proliferación y diferenciación de osteogénicas células madre / progenitoras endógenas en el proceso de reparación de fractura ósea.

Secuencial<em&gt; En vivo</em&gt; Imagen de células madre / progenitoras osteogénicas durante la reparación de la fractura

Bone turns over continuously and is highly regenerative following injury. Osteogenic stem/progenitor cells have long been hypothesized to exist, but in ...

sequential-vivo-imaging-osteogenic-stemprogenitor-cells-during

Research

JoVE Journal

Medicine

Sequential In vivo Imaging of Osteogenic Stem/Progenitor Cells During Fracture Repair

10.4K vistas.  Harvard Stem Cell Institute.  La medición cuantitativa de la función de progenitores de médula en la curación de la fractura requiere alta resolución tecnología de imágenes en serie. Aquí, se proporcionan protocolos para el uso de microscopía intravital y seguimiento osteo-linaje secuencialmente imagen y cuantificar la migración, proliferación y diferenciación de osteogénicas células madre / progenitoras endógenas en el proceso de reparación de fractura ósea. 

Video: Sequential In vivo Imaging of Osteogenic Stem/Progenitor Cells During Fracture Repair

In vivo Dual Substrate Bioluminescent Imaging

Our understanding of how and when breast cancer cells transit from established primary tumors to metastatic sites has increased at an exceptional rate since the advent of in vivo bioluminescent imaging technologies 1-3. Indeed, the ability to locate and quantify tumor growth longitudinally in a single cohort of animals to completion of the study as opposed to sacrificing individual groups of animals at specific assay times has revolutionized how researchers investigate breast cancer metastasis. Unfortunately, current methodologies preclude the real-time assessment of critical changes that transpire in cell signaling systems as breast cancer cells (i) evolve within primary tumors, (ii) disseminate throughout the body, and (iii) reinitiate proliferative programs at sites of a metastatic lesion. However, recent advancements in bioluminescent imaging now make it possible to simultaneously quantify specific spatiotemporal changes in gene expression as a function of tumor development and metastatic progression via the use of dual substrate luminescence reactions. To do so, researchers take advantage for two light-producing luciferase enzymes isolated from the firefly (Photinus pyralis) and sea pansy (Renilla reniformis), both of which react to mutually exclusive substrates that previously facilitated their wide-spread use in in vitro cell-based reporter gene assays 4. Here we demonstrate the in vivo utility of these two enzymes such that one luminescence reaction specifically marks the size and location of a developing tumor, while the second luminescent reaction serves as a means to visualize the activation status of specific signaling systems during distinct stages of tumor and metastasis development. Thus, the objectives of this study are two-fold. First, we will describe the steps necessary to construct dual bioluminescent reporter cell lines, as well as those needed to facilitate their use in visualizing the spatiotemporal regulation of gene expression during specific steps of the metastatic cascade. Using the 4T1 model of breast cancer metastasis, we show that the in vivo activity of a synthetic Smad Binding Element (SBE) promoter was decreased dramatically in pulmonary metastasis as compared to that measured in the primary tumor 4-6. Recently, breast cancer metastasis was shown to be regulated by changes within the primary tumor microenvironment and reactive stroma, including those occurring in fibroblasts and infiltrating immune cells 7-9. Thus, our second objective will be to demonstrate the utility of dual bioluminescent techniques in monitoring the growth and localization of two unique cell populations harbored within a single animal during breast cancer growth and metastasis.

In vivo Dual Substrate Bioluminescent Imaging

Herein we describe the methods to construct, visualize, and quantify the bioluminescent reactions of both firefly and renilla luciferase enzymes expressed in metastatic breast cancer cells during their growth and metastasis in vivo.

En vivo doble sustrato bioluminiscentes imagen

Our understanding of how and when breast cancer cells transit from established primary tumors to metastatic sites has increased at an exceptional rate ...

Investigación

Medicina

3D-Neuronavigation In Vivo Through a Patient's Brain During a Spontaneous Migraine Headache

A growing body of research, generated primarily from MRI-based studies, shows that migraine appears to occur, and possibly endure, due to the alteration of specific neural processes in the central nervous system. However, information is lacking on the molecular impact of these changes, especially on the endogenous opioid system during migraine headaches, and neuronavigation through these changes has never been done. This study aimed to investigate, using a novel 3D immersive and interactive neuronavigation (3D-IIN) approach, the endogenous &#181;-opioid transmission in the brain during a migraine headache attack in vivo. This is arguably one of the most central neuromechanisms associated with pain regulation, affecting multiple elements of the pain experience and analgesia. A 36 year-old female, who has been suffering with migraine for 10 years, was scanned in the typical headache (ictal) and nonheadache (interictal) migraine phases using Positron Emission Tomography (PET) with the selective radiotracer [11C]carfentanil, which allowed us to measure &#181;-opioid receptor availability in the brain (non-displaceable binding potential - &#181;OR BPND). The short-life radiotracer was produced by a cyclotron and chemical synthesis apparatus on campus located in close proximity to the imaging facility. Both PET scans, interictal and ictal, were scheduled during separate mid-late follicular phases of the patient's menstrual cycle. During the ictal PET session her spontaneous headache attack reached severe intensity levels; progressing to nausea and vomiting at the end of the scan session. There were reductions in &#181;OR BPND in the pain-modulatory regions of the endogenous &#181;-opioid system during the ictal phase, including the cingulate cortex, nucleus accumbens (NAcc), thalamus (Thal), and periaqueductal gray matter (PAG); indicating that &#181;ORs were already occupied by endogenous opioids released in response to the ongoing pain. To our knowledge, this is the first time that changes in &#181;OR BPND during a migraine headache attack have been neuronavigated using a novel 3D approach. This method allows for interactive research and educational exploration of a migraine attack in an actual patient's neuroimaging dataset.

3D-Neuronavigation In Vivo Through a Patient&#039;s Brain During a Spontaneous Migraine Headache

In this study, the authors report for the first time a novel 3D-Immersive &#38; Interactive Neuronavigation (3D-IIN) through the impact of a spontaneous migraine headache attack in the &#956;-opioid system of a patient's brain in vivo.

3D-Neuronavegación<em&gt; En Vivo</em&gt; A través del cerebro de un paciente durante una espontánea migraña

A growing body of research, generated primarily from MRI-based studies, shows that migraine appears to occur, and possibly endure, due to the alteration ...

In vivo 19F MRI for Cell Tracking

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. Here, we describe a general protocol for cell labeling, imaging, and image processing. The technique is applicable to various cell types and animal models, although here we focus on a typical mouse model for tracking murine immune cells. The most important issues for cell labeling are described, as these are relevant to all models. Similarly, key imaging parameters are listed, although the details will vary depending on the MRI system and the individual setup. Finally, we include an image processing protocol for quantification. Variations for this, and other parts of the protocol, are assessed in the Discussion section. Based on the detailed procedure described here, the user will need to adapt the protocol for each specific cell type, cell label, animal model, and imaging setup. Note that the protocol can also be adapted for human use, as long as clinical restrictions are met.

In vivo 19F MRI for Cell Tracking

We describe a general protocol for in vivo cell tracking using MRI in a mouse model with ex vivo labeled cells. A typical protocol for cell labeling, image acquisition processing and quantification is included.

In vivo MRI de 19F para el seguimiento de la célula

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. ...

In Vivo Dynamics of Retinal Microglial Activation During Neurodegeneration: Confocal Ophthalmoscopic Imaging and Cell Morphometry in Mouse Glaucoma

Microglia, which are CNS-resident neuroimmune cells, transform their morphology and size in response to CNS damage, switching to an activated state with distinct functions and gene expression profiles. The roles of microglial activation in health, injury and disease remain incompletely understood due to their dynamic and complex regulation in response to changes in their microenvironment. Thus, it is critical to non-invasively monitor and analyze changes in microglial activation over time in the intact organism. In vivo studies of microglial activation have been delayed by technical limitations to tracking microglial behavior without altering the CNS environment. This has been particularly challenging during chronic neurodegeneration, where long-term changes must be tracked. The retina, a CNS organ amenable to non-invasive live imaging, offers a powerful system to visualize and characterize the dynamics of microglia activation during chronic disorders.
This protocol outlines methods for long-term, in vivo imaging of retinal microglia, using confocal ophthalmoscopy (cSLO) and CX3CR1GFP/+ reporter mice, to visualize microglia with cellular resolution. Also, we describe methods to quantify monthly changes in cell activation and density in large cell subsets (200-300 cells per retina). We confirm the use of somal area as a useful metric for live tracking of microglial activation in the retina by applying automated threshold-based morphometric analysis of in vivo images. We use these live image acquisition and analyses strategies to monitor the dynamic changes in microglial activation and microgliosis during early stages of retinal neurodegeneration in a mouse model of chronic glaucoma. This approach should be useful to investigate the contributions of microglia to neuronal and axonal decline in chronic CNS disorders that affect the retina and optic nerve.

In Vivo Dynamics of Retinal Microglial Activation During Neurodegeneration: Confocal Ophthalmoscopic Imaging and Cell Morphometry in Mouse Glaucoma

Microglia activation and microgliosis are key responses to chronic neurodegeneration. Here, we present methods for in vivo, long-term visualization of retinal CX3CR1-GFP+ microglial cells by confocal ophthalmoscopy, and for threshold and morphometric analyses to identify and quantify their activation. We monitor microglial changes during early stages of age-related glaucoma.

En Vivo Dinámica de Retina Microglial Activación Durante Neurodegeneración: Confocal oftalmoscópico Imaging y Morfometría celular en el ratón Glaucoma

Microglia, which are CNS-resident neuroimmune cells, transform their morphology and size in response to CNS damage, switching to an activated state with ...

In Vivo Imaging and Tracking of Technetium-99m Labeled Bone Marrow Mesenchymal Stem Cells in Equine Tendinopathy

Recent advances in the application of bone marrow mesenchymal stem cells (BMMSC) for the treatment of tendon and ligament injuries in the horse suggest improved outcome measures in both experimental and clinical studies. Although the BMMSC are implanted into the tendon lesion in large numbers (usually 10 - 20 million cells), only a relatively small number survive (&#60;10%) although these can persist for up to 5 months after implantation. This appears to be a common observation in other species where BMMSC have been implanted into other tissues and it is important to understand when this loss occurs, how many survive the initial implantation process and whether the cells are cleared into other organs. Tracking the fate of the cells can be achieved by radiolabeling the BMMSC prior to implantation which allows non-invasive in vivo imaging of cell location and quantification of cell numbers.
This protocol describes a cell labeling procedure that uses Technetium-99m (Tc-99m), and tracking of these cells following implantation into injured flexor tendons in horses. Tc-99m is a short-lived (t1/2 of 6.01 hr) isotope that emits gamma rays and can be internalized by cells in the presence of the lipophilic compound hexamethylpropyleneamine oxime (HMPAO). These properties make it ideal for use in nuclear medicine clinics for the diagnosis of many different diseases. The fate of the labeled cells can be followed in the short term (up to 36 hr) by gamma scintigraphy to quantify both the number of cells retained in the lesion and distribution of the cells into lungs, thyroid and other organs. This technique is adapted from the labeling of blood leukocytes and could be utilized to image implanted BMMSC in other organs.

In Vivo Imaging and Tracking of Technetium-99m Labeled Bone Marrow Mesenchymal Stem Cells in Equine Tendinopathy

This protocol describes the radiolabeling of equine mesenchymal stem cells and their implantation into tendon injuries in the horse in order to determine cell survival and tissue distribution using gamma scintigraphy.

En vivo de imágenes y Seguimiento de tecnecio-99m Etiquetada células madre mesenquimales de médula ósea en Equinos tendinopatía

Recent advances in the application of bone marrow mesenchymal stem cells (BMMSC) for the treatment of tendon and ligament injuries in the horse suggest ...

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.

El estudio de cáncer de páncreas Tallo Características de las células para el desarrollo de nuevas estrategias de tratamiento

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

Depletion of Mouse Cells from Human Tumor Xenografts Significantly Improves Downstream Analysis of Target Cells

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic patient tumors in different assays1. Human tumor xenografts represent the gold standard with respect to tumor biology, drug discovery, and metastasis research 2-4. Tumor xenografts can be derived from different types of material like tumor cell lines, tumor tissue from primary patient tumors4 or serially transplanted tumors. When propagated in vivo, xenografted tissue is infiltrated and vascularized by cells of mouse origin. Multiple factors such as the tumor entity, the origin of xenografted material, growth rate and region of transplantation influence the composition and the amount of mouse cells present in tumor xenografts. However, even when these factors are kept constant, the degree of mouse cell contamination is highly variable.
Contaminating mouse cells significantly impair downstream analyses of human tumor xenografts. As mouse fibroblasts show high plating efficacies and proliferation rates, they tend to overgrow cultures of human tumor cells, especially slowly proliferating subpopulations. Mouse cell derived DNA, mRNA, and protein components can bias downstream gene expression analysis, next-generation sequencing, as well as proteome analysis 5. To overcome these limitations, we have developed a fast and easy method to isolate untouched human tumor cells from xenografted tumor tissue. This procedure is based on the comprehensive depletion of cells of mouse origin by combining automated tissue dissociation with the benchtop tissue dissociator and magnetic cell sorting. Here, we demonstrate that human target cells can be can be obtained with purities higher than 96% within less than 20 min independent of the tumor type.

Human tumor xenografts are vascularized and infiltrated by cells of mouse origin during the growth phase in vivo. To circumvent the bias caused by these contaminating cells during downstream analysis, we developed a method allowing for comprehensive depletion of all mouse cells by magnetic cell sorting.

El agotamiento de las células de ratón a partir de xenoinjertos de tumores humanos mejora significativamente análisis de aguas abajo de las células diana

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic ...

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The amount of the different tissues in the callus provides important information on the fracture healing progress. Available in vivo techniques to longitudinally monitor the callus tissue development in preclinical fracture-healing studies using small animals include digital radiography and &#181;CT imaging. However, both techniques are only able to distinguish between mineralized and non-mineralized tissue. Consequently, it is impossible to discriminate cartilage from fibrous tissue. In contrast, magnetic resonance imaging (MRI) visualizes anatomical structures based on their water content and might therefore be able to noninvasively identify soft tissue and cartilage in the fracture callus. Here, we report the use of an MRI-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice. The experiments demonstrated that the fixator and a custom-made mounting device allow repetitive MRI scans, thus enabling longitudinal analysis of fracture-callus tissue development.

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

The evaluation of tissue development in the fracture callus during endochondral bone healing is essential to monitor the healing process. Here, we report the use of a magnetic resonance imaging (MRI)-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice.

En Vivo Evaluación del desarrollo del callo de fractura durante la cicatrización ósea en ratones usando un dispositivo de osteosíntesis de MRI-compatible para el fémur de ratón

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The ...

Middle Cerebral Artery Occlusion Allowing Reperfusion via Common Carotid Artery Repair in Mice

The ischemic stroke is a major cause of adult long-term disability and death worldwide. The current treatments available are limited, with only tissue plasminogen activator (tPA) as an approved drug treatment to target ischemic strokes. Current research in the field of ischemic stroke focuses on better understanding the pathophysiology of stroke, to develop and investigate novel pharmaceutical targets. Reliable experimental stroke models are crucial for the progression of potential treatments. The middle cerebral artery occlusion (MCAO) model is clinically relevant and the most frequently used surgical model of ischemic stroke in rodents. However, the outcomes of this model, such as lesion volume, are associated with high levels of variability, particularly in mice. The alternative MCAO model described here allows the reperfusion of the common carotid artery (CCA) and the increased perfusion of the middle cerebral artery (MCA) territory, using a tissue pad with fibrinogen-based sealant to repair the vessel, and the improved welfare of the mice by avoiding external carotid artery (ECA) ligation. This reduces the reliance on the Circle of Willis, which is known to be highly anatomically variable in mice. Representative data show that using this alternative surgical approach decreases the variability in lesion volumes between the traditional MCAO approach and the alternative approach described here.

Intraluminal filament occlusion of the middle cerebral artery is the most frequently used in vivo model of experimental stroke in rodents. An alternative surgical approach to allow common carotid artery repair is performed here, which allows the reperfusion of the common carotid artery and a full reperfusion to the middle cerebral artery territory.

Oclusión de la arteria Cerebral Media permitiendo la reperfusión mediante la reparación de la arteria carótida común en ratones

The ischemic stroke is a major cause of adult long-term disability and death worldwide. The current treatments available are limited, with only tissue ...

A Simplified Stepwise Approach to Echo Guidance during Percutaneous Mitral Valve Repair

Percutaneous transcatheter edge-to-edge reconstruction of the mitral valve is a safe and well-established therapy for severe symptomatic mitral regurgitation in patients with high surgical risk. Echocardiographic guidance in addition to fluoroscopy is the gold standard and should be performed using a standardized technique.
This article lays out our reproducible step by step echocardiographic guide including views, measurements as well as highlighting possible difficulties that may arise during the procedure.
This article provides detailed and chronological echocardiographic views for each step of the procedure, especially preferences between 2D and 3D imaging. If needed, pulse wave, continuous wave and color doppler measurements are described. Furthermore, as there are no official recommendations for the quantification of mitral regurgitation during the percutaneous edge-to-edge-repair procedure, advice is also included for echocardiographic quantification after grasping the mitral leaflets and after device deployment. In addition, the article deals with important echocardiographic views to prevent and deal with possible complications during the procedure.
Echocardiographic guidance during transcatheter mitral valve repair is mandatory. A structured approach improves the collaboration between interventionist and imager and is indispensable for a safe and effective procedure.

This protocol presents in detail how to perform real-time echocardiographic guidance during transcatheter mitral valve repair. The fundamental views and the necessary measurements are described for each stage of the procedure.