Imágenes longitudinales se utiliza en estudios pre-clínicos para seguir el progreso de una enfermedad o medir el efecto de un agente terapéutico. En oncología, los métodos ópticos proporcionan herramientas rigurosas para controlar el crecimiento del tumor y entregar la cuantificación precisa del crecimiento celular o la expresión de genes en cada momento en dicho estudio. Cambios anatómicos se puede medir utilizando una técnica de alta resolución como microCT, pero para la imagen longitudinal una baja dosis de rayos X debe ser utilizado para evitar los artefactos biológicos. Imágenes ópticas y microCT pueden ser co-registro para la prestación de una combinación de datos funcionales y anatómicos asegurar que el máximo de información se extrae de un modelo animal. 1. Preparación de células <ol><li> Caliper ofrece una amplia gama de luciferasa expresando líneas celulares de cáncer de la investigación preclínica en modelos de ratón. </li><li> MDA-MB-231-luc-D2H2LN es un ser humano línea de células tumorales mamarias expresan el gen de la luciferasa, que puede ser utilizado como un indicador óptico de tumorgenesis en vivo. Esta línea celular se crea a partir de una metástasis de ganglios linfáticos espontánea que se originó a partir de un tumor mamario D3H1 almohadilla de grasa y se sabe que la forma agresiva de metástasis. </li><li> Las células se proporcionan como una cultura congelada libre de agentes patógenos que rápidamente crece en los medios de comunicación estándar, sin necesidad de marcadores de selección. </li><li> Para verificar la actividad de la luciferasa antes de la inyección en el animal un frasco de 90% confluentes se cosechan por tripsinización. La actividad luciferasa se mide mediante la supresión de 50.000 células en una placa de microtitulación y la realización de series de dilución. </li></ol> 2. Intracardiaca inyección de células en los animales <ol><li> Antes de la inyección, los animales son anestesiados utilizando el 3% de isoflurano. </li><li> 1-3 million células se inyectan en el volumen de 50 ul en el ventrículo izquierdo. Suspensión celular contiene 150ug/ml D-luciferina para validar la técnica de inyección. </li><li> Para confirmar una correcta inyección intracardíaca ratones son expuestas en el sistema de IVIS. Los ratones que muestran la señal de BLI en todo el cuerpo se han inyectado correctamente. Si la señal se localiza en las células no se les inyectó correctamente en el corazón. </li></ol> 3. BLI imágenes para controlar las metástasis <ol><li> El servicio de transporte de imagen compatible con el ratón para la captura de datos, tanto en espectro IVIS y el sistema de QuantumFX microCT. </li><li> El servicio de transporte ayuda a mantener al animal en la misma posición para la imagen e incorpora señales de fiabilidad en la ayuda automática de co-registro. La cámara está conectada al vaporizador isofluorance para mantener la anestesia. </li><li> Asistente de imágenes en el software de imagen viva 4.1 se puede utilizar para seleccionar automáticamente el tiempo de exposición, f-stop y hurgar en la basura y garantizar la recogida de datos cuantitativos. </li><li> Varias imágenes pueden ser adquiridas y comparados en los estudios longitudinales que cubren segundos o meses, dependiendo de la naturaleza del experimento. </li><li> El día 6 después de la inyección de las células, BLI imágenes con IVIS espectro muestra metástasis óseas en siete de los nueve ratones. </li></ol> 4. Seguimiento longitudinal de las lesiones osteolíticas con micro CT <ol><li> Los ratones que mostraron metástasis ósea visible con clara BLI fueron estudiados en el sistema Quantum FX micro CT. </li><li> El Quantum FX micro sistema CT proporciona imágenes de alta calidad a una dosis de rayos X lo suficientemente bajo como para permitir cierto longitudinal CT micro en estudios preclínicos. </li><li> Degradación de los huesos en ambas piernas puede ser longitudinal monitoreados utilizando este sistema en menos de un minuto. </li><li> Los ratones son anestesiados con isoflurano 3% y pueden ser transferidos directamente desde el sistema Spectrum IVIS. </li><li> Dos imágenes de 60mm se cosen para captar la opinión de animal. </li><li> Un campo de visión de 30 mm es ideal para obtener imágenes de la articulación de la rodilla en alta resolución. </li><li> Un solo escaneo con una resolución lo suficientemente alta como para medir y cuantificar las metástasis óseas sólo tarda 18 segundos y libera una dosis de 13mGy solamente. </li><li> Los ratones fueron estudiados hasta 8 veces en 36 días con el sistema de micro CT sin afectar el crecimiento del tumor o la salud del animal. </li><li> El micro de imágenes de TC mostraban que leisions huesos eran visibles en el día 10 y avanzó muy rápidamente, lo que corresponde al aumento de la señal de BLI. </li></ol> 5. 3D co-registro y el análisis de BLI y UCT <ol><li> Una vez que las imágenes han sido capturados en todo el ámbito IVIS y Quantum FX micro datos de la TC sistema puede ser co-registradas en una reconstrucción en 3D. </li><li> MicroCT imágenes se exportan como archivos DICOM y se cargan en la imagen viva 4,1 herramienta 3D de múltiples modalidades. </li><li> En el software de imagen viva de ejecutar el programa en tres dimensiones DLIT a reconstruir la señal óptica. </li><li> La herramienta de referencia en el software se utiliza para co-registro de la señal óptica BLI a la imagen de micro CT. </li><li> Conjuntos de datos corregistradas pueden ser analizados cuantitativamente para controlar múltiples parámetros en progresión de la enfermedad, aquí estamos el seguimiento del crecimiento del tumor metastásico junto con el desarrollo de la lesión osteolítica en el hueso. </li> &lt;/ Ol&gt;

<ol>
	<li>Jenkins, D. E., Hornig, Y. S., Oei, Y., Dusich, J., Purchio, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bioluminescent+Human+Breast+Cancer+Cell+Lines+that+Permit+Rapid+and+Sensitive+in+vivo+Detection+of+Mammary+Tumors+and+Multiple+Metastases+in+Immune+Deficient+Mice.">Bioluminescent Human Breast Cancer Cell Lines that Permit Rapid and Sensitive in vivo Detection of Mammary Tumors and Multiple Metastases in Immune Deficient Mice.</a> Breast Cancer Research. 7, R444-R454 (2005).</li><li>Cowey, S., Szafran, A. A., Kappes, J., Zinn, K. R., Siegal, G. P., Desmond, R. A., Kim, H., Evans, L., Hardy, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Breast+Cancer+Metastasis+to+Bone:+Evaluation+of+Bioluminescent+Imaging+and+MicroSPECT/CT+for+Detecting+Bone+Metastasis+in+Immunodeficient+Mice.">Breast Cancer Metastasis to Bone: Evaluation of Bioluminescent Imaging and MicroSPECT/CT for Detecting Bone Metastasis in Immunodeficient Mice.</a> Clinical and Experimental Metastasis. 24, 389-401 (2007).</li><li>Labrinidis, A., Hay, S., Liapis, V., Ponomarev, V., Findlay, D. M., Evdokiou, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zoledronic+Acid+Inhibits+Both+the+Osteolytic+and+Osteoblastic+Components+of+Osteosarcoma+Lesions+in+a+Mouse+Model.">Zoledronic Acid Inhibits Both the Osteolytic and Osteoblastic Components of Osteosarcoma Lesions in a Mouse Model.</a> Clinical Cancer Research. 15, (2009).</li><li>Kaijzel, E. L., Pluijm, G. v. a. n. d. e. r., Lowik, C. W. G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole-Body+Optical+Imaging+in+Animal+Models+to+Assess+Cancer+Development+and+Progression.">Whole-Body Optical Imaging in Animal Models to Assess Cancer Development and Progression.</a> Clinical Cancer Research. 13, 3490-3497 (2007).</li><li>Minn, A. J., Kang, Y., Serganova, I., Gupta, G. P., Giri, D. D., Doubrovin, M., Ponomarev, V., Gerald, W. L., Blasberg, R., Massague, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinct+Organ-Specific+Metastatic+Potential+of+Individual+Breast+Cancer+Cells+and+Primary+Tumors.">Distinct Organ-Specific Metastatic Potential of Individual Breast Cancer Cells and Primary Tumors.</a> The Journal of Clinical Investigation. 115, (2005).</li><li>Xu, H., Christensen, A., Kuo, C., Nilson, D., Lim, E., Whalen, J., Kim, J. B., Zhang, N., Singh, R., Oldfield, S., Troy, T., Rice, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Co-registration+of+in+vivo+Optical+Tomography+and+Micro-CT+for+Longitudinal+Studies.">Co-registration of in vivo Optical Tomography and Micro-CT for Longitudinal Studies.</a> Word Molecular Imaging Congress. , (2010).</li></ol>

Los autores son empleados de Caliper Life Sciences, que hacen que el instrumento presentado en este artículo.

Small animal imaging with microCT has been applied to monitoring osteolytic lesions under pathological conditions, such as tumor development (Cowey et al. 2007; Labrinidis et al., 2009). As bioluminescence imaging of luciferase labeled tumors has been widely adopted pre-clinically, co-registration of bioluminescence and microCT images provided a better definition of anatomical location of the bioluminescence signals (Kaijzel et al. 2007). Previous study with a luciferase labeled breast tumor cell line MDA-MB-231-luc-D3H2LN showed metastases to bone and development of osteolytic lesions following intra-cardiac injection (Jenkins et al 2005; Minn et al., 2005). In this study, we explored a longitudinal study of tumor metastases and osteolytic activity with combinatory optical and low-radiation-dose microCT imaging with the systemic MDA-MB-231-luc-D3H2LN metastasis model. We performed sequential imaging with IVIS Spectrum and Quantum FX microCT systems and achieved bioluminescence and CT co-registration with our newly developed Living Image 4.1 software (Heng et al., 2010). Bioluminescence imaging with IVIS provides non-invasive detection of the tumor cells with high sensitivity, allowing the tumors to be detected at early stage. Imaging with Quantum FX allows accurate 3D reconstruction of the bone lesions and detailed anatomical information. Quantum FX system offers low radiation dose imaging, which enables longitudinal monitoring of disease progression. Correlation of bone lesions and tumor metastases was depicted in the co-registered image, and the advantage of multimodality tracking of lesion development longitudinally was clearly demonstrated.

monitoring tumor metastases and osteolytic lesions with bioluminescence and micro ct imaging

Después del parto intracardíaca de MDA-MB-231-luc-D3H2LN células a ratones nu / nu, metástasis a distancia desarrollado en los animales inyectados. Imágenes de bioluminiscencia que utilizan el espectro IVIS fue contratado para supervisar la distribución y el desarrollo de las células tumorales siguiendo el procedimiento de entrega, incluyendo la reconstrucción DLIT para medir la señal de tumor y su ubicación. El desarrollo de las lesiones metastásicas en los tejidos del hueso provoca una actividad osteolítica y lesiones a la tibia y el fémur fueron evaluados longitudinalmente mediante micro CT. Imágenes se realizó con un sistema de Quantum FX micro CT con imágenes rápido y dosis bajas de rayos-X. La baja dosis de radiación permite múltiples sesiones de imagen para llevar a cabo con un acumulado de rayos X de dosis muy por debajo de DL50. Una imagen del ratón dispositivo de transporte fue utilizado para la imagen de forma secuencial a los ratones con dos IVIS Spectrum y FX cuántica lograr el posicionamiento exacto de los animales, tanto en la bioluminiscencia y las imágenes de TC. La óptica y conjuntos de datos de CT se co-registradas en 3-dimentions con la imagen viva de software 4.1. Este enfoque multi-modo permite una estrecha vigilancia del crecimiento tumoral y el desarrollo de forma simultánea con la actividad osteolítica.

Watch this Scientific Journal Video about Monitoring Tumor Metastases and Osteolytic Lesions with Bioluminescence and Micro CT Imaging at JoVE.com

Monitoring Tumor Metastases and Osteolytic Lesions with Bioluminescence and Micro CT Imaging

Un modelo experimental de ratón de las metástasis óseas se estableció después de la entrega intracardíaca de luciferasa que expresan las células del tumor mamario. El desarrollo de tumores y dio lugar a lesión osteolítica fueron controlados longitudinalmente con bioluminiscencia y micro TC.

Monitoreo metástasis tumorales y lesiones osteolíticas con bioluminiscencia y Micro Imágenes de TC

Following intracardiac delivery of MDA-MB-231-luc-D3H2LN cells to Nu/Nu mice, systemic metastases developed in the injected animals. Bioluminescence ...

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Video: Monitoring Tumor Metastases and Osteolytic Lesions with Bioluminescence and Micro CT Imaging

In vivo Bioluminescence Imaging of Tumor Hypoxia Dynamics of Breast Cancer Brain Metastasis in a Mouse Model

It is well recognized that tumor hypoxia plays an important role in promoting malignant progression and affecting therapeutic response negatively. There is little knowledge about in situ, in vivo, tumor hypoxia during intracranial development of malignant brain tumors because of lack of efficient means to monitor it in these deep-seated orthotopic tumors. Bioluminescence imaging (BLI), based on the detection of light emitted by living cells expressing a luciferase gene, has been rapidly adopted for cancer research, in particular, to evaluate tumor growth or tumor size changes in response to treatment in preclinical animal studies. Moreover, by expressing a reporter gene under the control of a promoter sequence, the specific gene expression can be monitored non-invasively by BLI. Under hypoxic stress, signaling responses are mediated mainly via the hypoxia inducible factor-1&alpha; (HIF-1&alpha;) to drive transcription of various genes. Therefore, we have used a HIF-1&alpha; reporter construct, 5HRE-ODD-luc, stably transfected into human breast cancer MDA-MB231 cells (MDA-MB231/5HRE-ODD-luc). In vitro HIF-1&alpha; bioluminescence assay is performed by incubating the transfected cells in a hypoxic chamber (0.1% O2) for 24 hr before BLI, while the cells in normoxia (21% O2) serve as a control. Significantly higher photon flux observed for the cells under hypoxia suggests an increased HIF-1&alpha; binding to its promoter (HRE elements), as compared to those in normoxia. Cells are injected directly into the mouse brain to establish a breast cancer brain metastasis model. In vivo bioluminescence imaging of tumor hypoxia dynamics is initiated 2 wks after implantation and repeated once a week. BLI reveals increasing light signals from the brain as the tumor progresses, indicating increased intracranial tumor hypoxia. Histological and immunohistochemical studies are used to confirm the in vivo imaging results. Here, we will introduce approaches of in vitro HIF-1&alpha; bioluminescence assay, surgical establishment of a breast cancer brain metastasis in a nude mouse and application of in vivo bioluminescence imaging to monitor intracranial tumor hypoxia.

In vivo Bioluminescence Imaging of Tumor Hypoxia Dynamics of Breast Cancer Brain Metastasis in a Mouse Model

Bioluminescence imaging of hypoxia inducible factor-1&alpha; activity is applied to monitor intracranial tumor hypoxia development in a breast cancer brain metastasis mouse model.

Imágenes in vivo de tumores bioluminiscencia Dinámica hipoxia de la metástasis cerebral cáncer de mama en un modelo de ratón

It is well recognized that tumor hypoxia plays an important role in promoting malignant progression and affecting therapeutic response negatively. There ...

Investigación

Medicina

Osmotic Drug Delivery to Ischemic Hindlimbs and Perfusion of Vasculature with Microfil for Micro-Computed Tomography Imaging

Preclinical research in animal models of peripheral arterial disease plays a vital role in testing the efficacy of therapeutic agents designed to stimulate microcirculation. The choice of delivery method for these agents is important because the route of administration profoundly affects the bioactivity and efficacy of these agents1,2. In this article, we demonstrate how to locally administer a substance in ischemic hindlimbs by using a catheterized osmotic pump. This pump can deliver a fixed volume of aqueous solution continuously for an allotted period of time. We also present our mouse model of unilateral hindlimb ischemia induced by ligation of the common femoral artery proximal to the origin of profunda femoris and epigastrica arteries in the left hindlimb. Lastly, we describe the in vivo cannulation and ligation of the infrarenal abdominal aorta and perfusion of the hindlimb vasculature with Microfil, a silicone radiopaque casting agent. Microfil can perfuse and fill the entire vascular bed (arterial and venous), and because we have ligated the major vascular conduit for exit, the agent can be retained in the vasculature for future ex vivo imaging with the use of small specimen micro-CT3.

We show here the in vivo insertion of an osmotic pump for constant local drug delivery and the creation of hindlimb ischemia in a mouse model. Moreover, the hindlimb vasculature is perfused with Microfil, a silicone radiopaque agent, to prepare for micro-computed tomography (micro-CT) imaging.

Osmótica Drug Delivery de miembros posteriores isquémicos y la perfusión de la vasculatura con Microfil para Micro-tomografía computarizada

Preclinical research in animal models of peripheral arterial disease plays a vital role in testing the efficacy of therapeutic agents designed to ...

Bioluminescence Imaging of an Immunocompetent Animal Model for Glioblastoma

In contrast to commonly reported human glioma xenograft animal models, GL261 murine glioma xenografts recapitulate nearly all relevant clinical and histopathologic features of the human disease. When GL261 cells are implanted intracranially in syngeneic C57BL/6 mice, the model has the added advantage of maintaining an intact immune microenvironment. Stable expression of luciferase in GL261 cells allows non-invasive cost effective bioluminescence monitoring of intracranial tumor growth. We have recently demonstrated that luciferase expression in GL261 cells does not affect the tumor growth properties, tumor cell immunomodulatory cytokine expression, infiltration of immune cells into the tumor, or overall survival of animals bearing the intracranial tumor. Therefore, it appears that the GL261 luciferase glioma model can be useful in the study of novel chemotherapeutic and immunotherapeutic modalities. Here we report the technique for generating stable luciferase expression in GL261 cells and how to study the in vitro and in vivo growth of the tumor cells by bioluminescence imaging.

GL261 glioma cells provide a useful immunocompetent animal model of glioblastoma. The goals of this protocol are to demonstrate proper techniques for monitoring intracranial tumor growth using in vivo bioluminescence imaging, and to verify the utility of luciferase-modified GL261 cells for studying tumor immunology and immunotherapeutic approaches for treating glioblastoma.

La bioluminiscencia de imágenes de un Modelo inmunocompetentes Animal para Glioblastoma

In contrast to commonly reported human glioma xenograft animal models, GL261 murine glioma xenografts recapitulate nearly all relevant clinical and ...

Bioluminescence-Based Tumor Quantification Method for Monitoring Tumor Progression and Treatment Effects in Mouse Lymphoma Models

Although bioluminescence imaging (BLI) shows promise for monitoring tumor burden in animal models of cancer, these analyses remain mostly qualitative. Here we describe a method for bioluminescence imaging to obtain a semi-quantitative analysis of tumor burden and treatment response. This method is based on the calculation of a luminoscore, a value that allows comparisons of two animals from the same or different experiments. Current BLI instruments enable the calculation of this luminoscore, which relies mainly on the acquisition conditions (back and front acquisitions) and the drawing of the region of interest (manual markup around the mouse). Using two previously described mouse lymphoma models based on cell engraftment, we show that the luminoscore method can serve as a noninvasive way to verify successful tumor cell inoculation, monitor tumor burden, and evaluate the effects of in situ cancer treatment (CpG-DNA). Finally, we show that this method suits different experimental designs. We suggest that this method be used for early estimates of treatment response in preclinical small-animal studies.

Bioluminescence imaging is a well-known tool for localizing tumors and metastases, but quantification of these images often requires complex calculations and particular instruments. We describe the easy-to-use luminoscore method, based on precise acquisition conditions, requiring no calculations, and enabling tumor burden and treatment response to be monitored in mouse models.

Método de cuantificación del tumor bioluminiscencia-base para la progresión tumoral Monitoreo y efectos del tratamiento en modelos de ratón linfoma

Although bioluminescence imaging (BLI) shows promise for monitoring tumor burden in animal models of cancer, these analyses remain mostly qualitative. ...

Combined Near-infrared Fluorescent Imaging and Micro-computed Tomography for Directly Visualizing Cerebral Thromboemboli

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of stroke than relying on indirect measurements, and will be a potent and robust vascular research tool. We use an optical imaging approach that labels thrombi with a molecular imaging thrombus marker&#160;&#8212; a Cy5.5 near-infrared fluorescent (NIRF) probe that is covalently linked to the fibrin strands of the thrombus by the fibrin-crosslinking enzymatic action of activated coagulation factor XIIIa during the process of clot maturation. A micro-computed tomography (microCT)-based approach uses thrombus-seeking gold nanoparticles (AuNPs) functionalized to target the major component of the clot: fibrin. This paper describes a detailed protocol for the combined in vivo microCT and ex vivo NIRF imaging of thromboemboli in a mouse model of embolic stroke. We show that in vivo microCT and fibrin-targeted glycol-chitosan AuNPs (fib-GC-AuNPs) can be used for visualizing both in situ thrombi and cerebral embolic thrombi. We also describe the use of in vivo microCT-based direct thrombus imaging to serially monitor the therapeutic effects of tissue plasminogen activator-mediated thrombolysis. After the last imaging session, we demonstrate by ex vivo NIRF imaging the extent and the distribution of residual thromboemboli in the brain. Finally, we describe quantitative image analyses of microCT and NIRF imaging data. The combined technique of direct thrombus imaging allows two independent methods of thrombus visualization to be compared: the area of thrombus-related fluorescent signal on ex vivo NIRF imaging vs. the volume of hyperdense microCT thrombi in vivo.

This protocol describes the application of combined near-infrared fluorescent (NIRF) imaging and micro-computed tomography (microCT) for visualizing cerebral thromboemboli. This technique allows the quantification of thrombus burden and evolution. The NIRF imaging technique visualizes fluorescently labeled thrombus in excised brain, while the microCT technique visualizes thrombus inside living animals using gold-nanoparticles.

Imagen Fluorescente combinado del infrarrojo cercano y la tomografía computarizada-Micro para visualizar de manera directa tromboembolia cerebral

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of ...

Determining Glucose Metabolism Kinetics Using 18F-FDG Micro-PET/CT

This paper describes the use of 18F-FDG and micro-PET/CT imaging to determine in vivo glucose metabolism kinetics in mice (and is transferable to rats). Impaired uptake and metabolism of glucose in multiple organ systems due to insulin resistance is a hallmark of type 2 diabetes. The ability of this technique to extract an image-derived input function from the vena cava using an iterative deconvolution method eliminates the requirement of the collection of arterial blood samples. Fitting of tissue and vena cava time activity curves to a two-tissue, three compartment model permits the estimation of kinetic micro-parameters related to the 18F-FDG uptake from the plasma to the intracellular space, the rate of transport from intracellular space to plasma and the rate of 18F-FDG phosphorylation. This methodology allows for multiple measures of glucose uptake and metabolism kinetics in the context of longitudinal studies and also provides insights into the efficacy of therapeutic interventions.

Determining Glucose Metabolism Kinetics Using 18F-FDG Micro-PET/CT

This study describes a protocol that uses 18F-FDG and positron emission tomography/computed tomography (PET/CT) imaging, together with kinetic modelling, to quantify the in vivo, real-time uptake of 18F-FDG into tissues.

La determinación de metabolismo de la glucosa Kinetics Uso<sup&gt; 18</sup&gt; F-FDG Micro-PET / CT

This paper describes the use of 18F-FDG and micro-PET/CT imaging to determine in vivo glucose metabolism kinetics in mice (and is transferable to rats). ...

Induction and Micro-CT Imaging of Cerebral Cavernous Malformations in Mouse Model

Mutations in the CCM1 (aka KRIT1), CCM2, or CCM3 (aka PDCD10) gene cause cerebral cavernous malformation (CCM) in humans. Mouse models of CCM disease have been established by tamoxifen induced deletion of Ccm genes in postnatal animals. These mouse models provide invaluable tools to investigate molecular mechanism and therapeutic approaches for CCM disease. An accurate and quantitative method to assess lesion burden and progression is essential to harness the full value of these animal models. Here, we demonstrate the induction of CCM disease in a mouse model and the use of the contrast enhanced X-ray micro computed tomography (micro-CT) method to measure CCM lesion burden in mouse brains. At postnatal day 1 (P1), we used 4-hydroxytamoxifen (4HT) to activate Cre recombinase activity from the Cdh5-CreErt2 transgene to cleave the floxed allele of Ccm2. CCM lesions in mouse brains were analyzed at P8. For micro-CT, iodine based Lugol&#39;s solution was used to enhance contrast in brain tissue. We have optimized the scan parameters and utilized a voxel dimension of 9.5 &#181;m, which lead to a minimum feature size of approximately 25 &#181;m. This resolution is sufficient to measure CCM lesion volume and number globally and accurately, and provide high-quality 3-D mapping of CCM lesions in mouse brains. This method enhances the value of the established mouse models to study the molecular basis and potential therapies for CCM and other cerebrovascular diseases.

This protocol demonstrates the induction of cerebral cavernous malformation disease in a mouse model and uses contrast enhanced micro computed tomography to measure lesion burden. This method enhances the value of established mouse models to study the molecular basis and potential therapies for cerebral cavernous malformation and other cerebrovascular diseases.

Inducción y Micro-CT en la proyección de imagen de malformaciones cavernosas cerebrales en modelo murino

Mutations in the CCM1 (aka KRIT1), CCM2, or CCM3 (aka PDCD10) gene cause cerebral cavernous malformation (CCM) in humans. Mouse models of CCM disease have ...

Quantitative Micro-CT Analysis of Aortopathy in a Mouse Model of &#946;-aminopropionitrile-induced Aortic Aneurysm and Dissection

Aortic aneurysm and dissection is associated with significant morbidity and mortality in the population and can be highly lethal. While animal models of aortic disease exist, in vivo imaging of the vasculature has been limited. In recent years, micro-computerized tomography (micro-CT) has emerged as a preferred modality for imaging both large and small vessels both in vivo and ex vivo. In conjunction with a method of vascular casting, we have successfully used micro-CT to characterize the frequency and distribution of aortic pathology in &#946;-aminopropionitrile-treated C57/Bl6 mice. Technical limitations of this method include variations in the quality of the perfusion introduced by poor animal preparation, the application of proper methodologies for vessel size quantification, and the non-survivability of this procedure. This article details a methodology for the intravascular perfusion of a lead-based radiopaque silicone rubber for the quantitative characterization of aortopathy in a mouse model of aneurysm and dissection. In addition to visualizing aortic pathology, this method may be used for examining other vascular beds in vivo or vascular beds removed post-mortem.

Quantitative Micro-CT Analysis of Aortopathy in a Mouse Model of &amp;#946;-aminopropionitrile-induced Aortic Aneurysm and Dissection

This article describes a detailed methodology of using a radiopaque lead-based silicone rubber to perfuse the murine vasculature for aortic diameter quantification in a mouse model of aortic aneurysm and dissection.

Análisis de Micro-CT cuantitativa de Aortopathy en un modelo murino de disección y aneurisma de la aorta inducida por β-oxidasa

Aortic aneurysm and dissection is associated with significant morbidity and mortality in the population and can be highly lethal. While animal models of ...

Dual Bioluminescence Imaging of Tumor Progression and Angiogenesis

Angiogenesis, as a crucial process of tumor progression, has become a research hotspot and target of anti-tumor therapy. However, there is no reliable model for tracing tumor progression and angiogenesis simultaneously in a visual and sensitive manner. Bioluminescence imaging displays its unique superiority in living imaging due to its advantages of high sensitivity, strong specificity, and accurate measurement. Presented here is a protocol to establish a tumor-bearing mouse model by injecting a Renilla luciferase-labeled murine breast cancer cell line 4T1 into the transgenic mouse with angiogenesis-induced Firefly luciferase expression. This mouse model provides a valuable tool to simultaneously monitor tumor progression and angiogenesis in real-time by dual bioluminescence imaging in a single mouse. This model may be widely applied in anti-tumor drug screening and oncology research.

This protocol describes the establishment of a tumor-bearing mouse model to monitor tumor progression and angiogenesis in real-time by dual bioluminescence imaging.

Imagen de bioluminiscencia dual de la progresión tumoral y la angiogénesis

Angiogenesis, as a crucial process of tumor progression, has become a research hotspot and target of anti-tumor therapy. However, there is no reliable ...

Evaluation of Capnography Sampling Line Compatibility and Accuracy when Used with a Portable Capnography Monitor

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment of end-tidal CO2 (ETCO2), its accuracy is commonly validated using commercial kits composed of a capnography monitor and its matching disposable nasal cannula sampling lines. The purpose of this study was to assess the compatibility and accuracy of cross-paired capnography sampling lines with a single portable bedside capnography monitor. A series of 4 bench tests were performed to evaluate the tensile strength, rise time, ETCO2 accuracy as a function of respiratory rate, and ETCO2 accuracy in the presence of supplemental O2. Each bench test was performed using specialized, validated equipment to allow for a full evaluation of sampling line performance. The 4 bench tests successfully differentiated between sampling lines from different commercial sources and suggested that due to increased rise time and decreased ETCO2 accuracy, not all nasal cannula sampling lines provide reliable clinical data when cross-paired with a commercial capnography monitor. Care should be taken to ensure that any cross-pairing of capnography monitors and disposable sampling lines is fully validated for use across respiratory rates and supplemental O2 flow rates commonly encountered in clinical settings.

The goal of this study was to evaluate the accuracy of capnography sampling lines used in conjunction with a portable bedside capnography monitor. Sampling lines from 7 manufacturers were evaluated for tensile strength, rise time, and ETCO2 accuracy as a function of respiratory rate or supplemental oxygen flow rate.

Evaluación de la compatibilidad y precisión de la línea de muestreo de capnografía cuando se utiliza con un monitor de capnografía portátil

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment ...