Agradecemos a R. Heintzmann para un debate fructífero en el desarrollo del enfoque de la iluminación a rayas, K. y A. Rajewsky Haberman para proporcionar ratones transgénicos C57BL / 6 B1-8 GFP. Reconocemos la Deutsche Forschungsgemeinschaft en virtud de concesión NI1167/3-1 (RN), HA5354/4-1 y SFB633, A15 proyecto (AEH), la Charité en virtud de concesión Rahel-Hirsch comunión (RN) por el apoyo financiero. Reconocemos en particular la red de JIMI para un debate fructífero y apoyo de infraestructura

<ol>
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L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Supraresolution+imaging+in+brain+slices+using+stimulated-emission+depletion+two-photon+laser+scanning+microscopy.">Supraresolution imaging in brain slices using stimulated-emission depletion two-photon laser scanning microscopy.</a> Neuron. 63 (4), 429-437 (2009).</li><li>Bianchini, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-wavelength+two-photon+excitation+-+stimulated+emission+depletion+(SW2PE-STED)+super-resolution+imaging.">Single-wavelength two-photon excitation - stimulated emission depletion (SW2PE-STED) super-resolution imaging.</a> Proc. Natl. Acad. Sci. U.S.A. 109 (17), 6390-6393 (2012).</li><li>Berning, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoscopy+in+a+living+mouse+brain.">Nanoscopy in a living mouse brain.</a> Science. 335 (6068), 551 (2012).</li><li>York, A. 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=Resolution+doubling+in+live,+multicellular+organisms+via+multifocal+structured+illumination+microscopy.">Resolution doubling in live, multicellular organisms via multifocal structured illumination microscopy.</a> Nat. Methods. 9, 749-754 (2012).</li><li>Gu, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Advanced optical imaging. , (2001).</li><li>Cha, J. W., Ballesta, J., So, P. T. 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Volker Andresen es accionista de LaVision Biotec GmbH, Bielefeld, Alemania. Los otros autores no tienen ningún conflicto de intereses.

El objetivo de formación de imágenes ópticas intravital es visualizar de forma dinámica y funcionalmente la motilidad celular y las interacciones con el fin de comprender la función del órgano en la salud y la enfermedad del tejido y 5. La tecnología más potente para lograr esto, de múltiples fotones láser microscopía de barrido, todavía tiene que superar las limitaciones relacionadas con las distorsiones de onda frontal, la dispersión, la adquisición lenta, photobleaching y fotodaño, que limit...

Dos fotones de láser microscopía de barrido (TPLSM), con sus ventajas para la formación de imágenes de los tejidos profundos relacionados con infrarrojos ultracorto excitación pulsada 1, ha revolucionado nuestra visión sobre los procesos vitales a nivel de células individuales mediante la revelación de la motilidad y la interacción de los diversos patrones subconjuntos de células en animales vivos 2-5. Sin embargo, la tecnología actual sigue siendo insuficiente para esclarecer los mecanismos de la función del órgano y la disfunción, como requisito previo para el desarrollo de nuevas estrategias terapéuticas, ya que hace sólo escasa información acerca de las bases moleculares de la respuesta celular en los tejidos en la salud y la enfermedad. La tecnología actual permite sólo una ventana espacial de unos pocos cientos de micras debido a la dispersión y la onda efectos de distorsión del frente sobre la resolución espacial y la relación señal-ruido 6, que son particularmente evidentes en el tejido altamente compacta de animales adultos. Estos dispersión y oleaje efectos de distorsión del frente se deben a una una gran heterogeneidadd distribución anisotrópica del índice de refracción en el tejido, lo que en un primer paso a un deterioro dependiente de la profundidad de la resolución espacial en 3D y finalmente a la pérdida total de la señal procedente de los fotones de excitación balísticos, es decir, la pérdida de la relación señal-ruido. En términos de biocientífico y aplicaciones de tejido profundo biomédicas, esto significa que la tecnología actual no puede revelar de manera inequívoca la comunicación celular causa una pobre resolución daría lugar a interacciones falsamente positivos, mientras que la disminución de la relación señal-ruido podría provocar que el sistema pasa por alto algunos interacciones entre estructuras tenues. Con el fin de detectar inequívocamente las interacciones celulares en una forma dinámica, se necesita una resolución espacial muy mejorada profunda dentro del tejido. Las técnicas Nanoscopia potentes introducidos actualmente basándose en algoritmos numéricos especiales, por ejemplo, enfoques estructura de iluminación, en el agotamiento del primer estado excitado, por ejemplo, </em&gt; STED, RESOLFT, o en la localización de la molécula, por ejemplo dSTORM, PALM, han encontrado muchas aplicaciones en las células fijadas, así como en cultivos de células en vivo 7. Sin embargo, con el fin de extender estas aplicaciones para secciones de tejidos, los tejidos vivos y organismos que todavía tenemos que superar las dificultades técnicas severas. Excitación de dos fotones Sted con diferentes longitudes de onda, así como con una sola longitud de onda (sw2PE-STED) para la excitación y la emisión estimulada se ha aplicado para mejorar la resolución lateral en rodajas de cerebro de 8 o en matrices artificiales con células embebidas 9, respectivamente, en la misma resolución axial como TPLSM estándar. Uso de un fotón STED, la dinámica de las espinas dendríticas podrían ser reflejados en la superficie de la corteza cerebral (hasta 10-15 m de profundidad) en un ratón vivo Thy1 EGFP a una resolución de 67 nm 10. Una herramienta versátil para la biología del desarrollo es proporcionada por el multifocal microscopía estructurada-iluminación, que proporciona doble mejorado 2Dresolución. Sin embargo, esta técnica sólo se puede utilizar en organismos con una baja propensión de dispersión de la luz, tales como embriones de pez cebra 11. Sin embargo, ninguna de estas técnicas se puede aplicar en el tejido altamente dispersión de animales adultos en varios cientos de micrómetros, que son modelos importantes para la investigación biomédica y clínica de las enfermedades con inicio después del nacimiento. Independiente de la aproximación utilizada para calcular la forma de onda frontal de difracción limitada, es decir, la función de dispersión de punto (PSF), después de enfocar a través de una lente, la anchura de la PSF a lo largo del eje óptico (resolución axial) es al menos tres veces más grande que la anchura de fibras discontinuas de poliéster perpendicular al eje óptico (resolución lateral) 12. Ola distorsiones del frente de diferentes órdenes cuantificados por los coeficientes de Zernike modificar considerablemente la forma del frente de onda de la onda electromagnética enfocada en imágenes de tejido profundo que conduce a mucho más grandes PSF, en especial a lo largo de la ópticaal eje 13-15. Por lo tanto, tanto las leyes de difracción y los efectos de distorsión del frente de onda apuntan a la resolución a lo largo del eje óptico tal como el factor limitante en la formación de imágenes de tejido profundo. Considerando que las técnicas de Nanoscopia se centran en contrarrestar los límites de difracción sólo, se necesita una tecnología que mejora la resolución y el contraste al contrarrestar tanto la difracción y los efectos de distorsión de la onda frontal axial para intravital de imágenes de alta resolución. Lo ideal sería que esta técnica debe ser también lo suficientemente rápido como para permitir el seguimiento de la dinámica celular. La corrección en tiempo real de las aberraciones de PSF y pérdida de contraste usando óptica adaptativa en TPLSM ha sido ampliamente estudiado y mejorado en la última década 13,14,16-18 y por lo tanto es la mejor opción disponible en la actualidad conduce a una mejor gestión de la excitación balístico aquellos fotones 14. Sin embargo, debido al hecho de que la mayor ola de corrección frente a los enfoques utilizados en óptica adaptativa es iterativo y que HÃve que ser repetido para áreas pequeñas (unos pocos 10 x 10 m 2) debido a la alta heterogeneidad del índice de refracción en el tejido, la velocidad de adquisición es significativamente menor que la necesaria para la motilidad celular de formación de imágenes y la comunicación. Por otra parte, el límite físico de adaptación óptica mejorada TPLSM todavía está determinado por difracción. La modulación espacial de la iluminación (SPIN) y modulación temporal en el lado de detección (PALA) se han propuesto teóricamente para ser aplicado a la microscopía de escaneo láser para mejorar la resolución. Su aplicación práctica en intravital de imágenes aún queda por demostrar 19. En conjunto, hay una gran demanda para el desarrollo de las tecnologías, que mejoran la resolución de imágenes de tejido profundo en vivir los animales adultos. En este trabajo, logramos modulación espacial del patrón de excitación mediante el control del proceso de digitalización en la multi-haz-iluminación rayas multi-fotón láser-smicroscopía enlatado (MB-SI-MPLSM) 20. Contrariamente a los enfoques iluminación estructurada, en la que la sección transversal del haz de excitación se modula espacialmente, utilizamos solamente el proceso de exploración para lograr la modulación espacial de la excitación. Con la ampliación de la excitación a una longitud de onda más larga, que son capaces de mejorar la resolución espacial y la relación señal-ruido en profundidad de los tejidos de alta dispersión de tejido (por ejemplo, los ganglios linfáticos, el camino libre dispersión de 47 m 6), independientemente de la óptica señal no lineal que detectamos, por ejemplo, fluorescencia, segunda generación armónica u otra frecuencia de mezcla fenómeno. El uso de este enfoque en longitudes de onda de excitación de hasta 900 nm podemos imagen dinámicamente las estructuras de proteínas celulares en la escala de pocas moléculas en los centros germinales de los ganglios linfáticos de ratón. Por lo tanto, podemos visualizar mejor la interacción entre unidades de antígeno llevar en la superficie de las células dendríticas foliculares y células B en el proceso de sondeo de la lucha contraGen durante la respuesta inmune en los órganos linfoides secundarios.

<table border="0" cellpadding="0" cellspacing="0" width="600">
	<tbody>
		<tr height="41">
			<td height="41" style="height:41px;width:216px;">ATTO590 &#8211; NSH for coupling</td>
			<td style="width:99px;">ATTO Tec, Germany</td>
			<td style="width:119px;">AD-590-35</td>
			<td style="width:167px;">-</td>
		</tr>
		<tr height="81">
			<td height="81" style="height:81px;width:216px;">CD21/35 &#8211; Fab fragment &#8211; ATTO590</td>
			<td style="width:99px;">DRFZ, Berlin</td>
			<td style="width:119px;">-</td>
			<td style="width:167px;">The coupling reaction was performed in the central lab of our institution.</td>
		</tr>
		<tr height="81">
			<td height="81" style="height:81px;width:216px;">B1-8 Jk-/- EGFP+</td>
			<td style="width:99px;">Prof. Anne Habermann, Yale Univ., CA, US</td>
			<td style="width:119px;">-</td>
			<td style="width:167px;">Can be also found at Jackson Laboratories (JAX).</td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:216px;">EasySep Negative Selection Mouse B Cell Enrichment&#160;</td>
			<td style="width:99px;">StemmCell Technologies, Germany</td>
			<td style="width:119px;">19854</td>
			<td style="width:167px;">-</td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:216px;">Polystyren beads (605), 0.2 &#181;m</td>
			<td style="width:99px;">Life Technologies, Germany</td>
			<td style="width:119px;">F8803</td>
			<td style="width:167px;">-</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;"></td>
			<td style="width:99px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;"></td>
			<td style="width:99px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:216px;">Name of Equipment</td>
			<td style="width:99px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments/Description</td>
		</tr>
		<tr height="81">
			<td height="81" style="height:81px;width:216px;">TriMScope I</td>
			<td style="width:99px;">LaVision Biotec, Bielefeld, Germany</td>
			<td style="width:119px;">-</td>
			<td style="width:167px;">-</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:216px;">OPO (manual version)</td>
			<td style="width:99px;">APE, Berlin, Germany</td>
			<td style="width:119px;">-</td>
			<td style="width:167px;">-</td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:216px;">Ti:Sa Laser Chameleon Ultra II</td>
			<td style="width:99px;">Coherent, Duisburg, Germany</td>
			<td style="width:119px;">-</td>
			<td style="width:167px;">-</td>
		</tr>
		<tr height="81">
			<td height="81" style="height:81px;width:216px;">water-immersion objective lens, 20x, NA 0.95, IR, WD 2 mm</td>
			<td style="width:99px;">Olympus Germany, Hamburg, Germany</td>
			<td style="width:119px;">-</td>
			<td style="width:167px;">-</td>
		</tr>
	</tbody>
</table>

highly resolved intravital striped-illumination microscopy of germinal centers

Control de la comunicación celular por intravital de tejido profundo de múltiples fotones microscopía es la clave para entender el destino de las células inmunes dentro de muestras de tejido de espesor y órganos en la salud y la enfermedad. Al controlar el patrón de exploración en microscopía de múltiples fotones y la aplicación de algoritmos numéricos apropiados, hemos desarrollado un enfoque de rayas-iluminación, lo que nos permitió lograr 3 veces mejor resolución axial y la mejora de la relación señal a ruido, es decir el contrario, en más de 100 profundidad del tejido micras dentro altamente dispersante tejido de los órganos linfoides en comparación con la microscopía de multi-estándar de fotón. La velocidad de adquisición, así como photobleaching y fotolesiones efectos fueron similares a la técnica basada en la foto-multiplicador estándar, mientras que la profundidad de formación de imágenes era ligeramente inferior debido a la utilización de detectores de campo. Utilizando el enfoque de la iluminación de rayas, somos capaces de observar la dinámica de los depósitos de complejos inmunes en las células dendríticas foliculares secundarias ̵1; en el nivel de un par de moléculas de proteína en los centros germinales.

La resolución espacial en los ganglios linfáticos Las dimensiones de la función de dispersión de punto efectiva (epsf) corresponden a la resolución espacial de un microscopio 12. Medimos esta función triple dimensión mediante la adquisición de la señal de la segunda generación de armónicos de las fibras de colágeno en los ganglios linfáticos por nuestro MB-SI-TPLSM en comparación con las técnicas establecidas de dos fotones microscopía de escaneo láser, es decir<...

Watch this Scientific Journal Video about Highly Resolved Intravital Striped-illumination Microscopy of Germinal Centers at JoVE.com

Highly Resolved Intravital Striped-illumination Microscopy of Germinal Centers

De alta resolución de imagen intravital con mejor contraste de hasta 120 m de profundidad en los ganglios linfáticos de ratones adultos se consigue modular espacialmente el patrón de excitación de un multi-focal del microscopio de dos fotones. En 100 m de profundidad se midió resoluciones de 487 nm (laterales) y 551 nm (axial), eludiendo así los límites de dispersión y difracción.

Muy resuelto Microscopía intravital rayas-iluminación de centros germinales

Monitoring cellular communication by intravital deep-tissue multi-photon microscopy is the key for understanding the fate of immune cells within thick ...

highly-resolved-intravital-striped-illumination-microscopy-germinal

Research

JoVE Journal

Immunology and Infection

9.9K vistas.  Leibniz Institute.  De alta resolución de imagen intravital con mejor contraste de hasta 120 m de profundidad en los ganglios linfáticos de ratones adultos se consigue modular espacialmente el patrón de excitación de un multi-focal del microscopio de dos fotones. En 100 m de profundidad se midió resoluciones de 487 nm (laterales) y 551 nm (axial), eludiendo así los límites de dispersión y difracción. 

Video: Highly Resolved Intravital Striped-illumination Microscopy of Germinal Centers

Intravital Microscopy of the Inguinal Lymph Node

Lymph nodes (LN's), located throughout the body, are an integral component of the immune system. They serve as a site for induction of adaptive immune response and therefore, the development of effector cells. As such, LNs are key to fighting invading pathogens and maintaining health. The choice of LN to study is dictated by accessibility and the desired model; the inguinal lymph node is well situated and easily supports studies of biologically relevant models of skin and genital mucosal infection.
The inguinal LN, like all LNs, has an extensive microvascular network supplying it with blood. In general, this microvascular network includes the main feed arteriole of the LN that subsequently branches and feeds high endothelial venules (HEVs). HEVs are specialized for facilitating the trafficking of immune cells into the LN during both homeostasis and infection. How HEVs regulate trafficking into the LN under both of these circumstances is an area of intense exploration. The LN feed arteriole, has direct upstream influence on the HEVs and is the main supply of nutrients and cell rich blood into the LN. Furthermore, changes in the feed arteriole are implicated in facilitating induction of adaptive immune response. The LN microvasculature has obvious importance in maintaining an optimal blood supply to the LN and regulating immune cell influx into the LN, which are crucial elements in proper LN function and subsequently immune response. 
The ability to study the LN microvasculature in vivo is key to elucidating how the immune system and the microvasculature interact and influence one another within the LN. Here, we present a method for in vivo imaging of the inguinal lymph node. We focus on imaging of the microvasculature of the LN, paying particular attention to methods that ensure the study of healthy vessels, the ability to maintain imaging of viable vessels over a number of hours, and quantification of vessel magnitude. Methods for perfusion of the microvasculature with vasoactive drugs as well as the potential to trace and quantify cellular traffic are also presented. 
Intravital microscopy of the inguinal LN allows direct evaluation of microvascular functionality and real-time interface of the direct interface between immune cells, the LN, and the microcirculation. This technique potential to be combined with many immunological techniques and fluorescent cell labelling as well as manipulated to study vasculature of other LNs.

A technique for performing intravital microscopy of the inguinal lymph node (LN) is outlined. Such technique allows for real-time, in vivo study of the lymph node microvasculature and structure both during homeostasis and infection. This technique can be adapted to cell trafficking studies and to other lymph node sites.

Microscopia intravital de los ganglios linfáticos inguinales

Lymph nodes (LN's), located throughout the body, are an integral component of the immune system. They serve as a site for induction of adaptive immune ...

Investigación

Inmunología e Infección

Tracking Neutrophil Intraluminal Crawling, Transendothelial Migration and Chemotaxis in Tissue by Intravital Video Microscopy

The recruitment of circulating leukocytes from blood stream to the inflamed tissue is a crucial and complex process of inflammation1,2. In the postcapillary venules of inflamed tissue, leukocytes initially tether and roll on the luminal surface of venular wall. Rolling leukocytes arrest on endothelium and undergo firm adhesion in response to chemokine or other chemoattractants on the venular surface. Many adherent leukocytes relocate from the initial site of adhesion to the junctional extravasation site in endothelium, a process termed intraluminal crawling3. Following crawling, leukocytes move across endothelium (transmigration) and migrate in extravascular tissue toward the source of chemoattractant (chemotaxis)4. Intravital microscopy is a powerful tool for visualizing leukocyte-endothelial cell interactions in vivo and revealing cellular and molecular mechanisms of leukocyte recruitment2,5. In this report, we provide a comprehensive description of using brightfield intravital microscopy to visualize and determine the detailed processes of neutrophil recruitment in mouse cremaster muscle in response to the gradient of a neutrophil chemoattractant. To induce neutrophil recruitment, a small piece of agarose gel (~1-mm3 size) containing neutrophil chemoattractant MIP-2 (CXCL2, a CXC chemokine) or WKYMVm (Trp-Lys-Tyr-Val-D-Met, a synthetic analog of bacterial peptide) is placed on the muscle tissue adjacent to the observed postcapillary venule. With time-lapsed video photography and computer software ImageJ, neutrophil intraluminal crawling on endothelium, neutrophil transendothelial migration and the migration and chemotaxis in tissue are visualized and tracked. This protocol allows reliable and quantitative analysis of many neutrophil recruitment parameters such as intraluminal crawling velocity, transmigration time, detachment time, migration velocity, chemotaxis velocity and chemotaxis index in tissue. We demonstrate that using this protocol, these neutrophil recruitment parameters can be stably determined and the single cell locomotion conveniently tracked in vivo.

We describe a protocol of brightfield intravital microscopy for measuring dynamic neutrophil-endothelial cell interactions during neutrophil recruitment in response to the source of a neutrophil chemoattractant in vivo. Neutrophil intraluminal crawling, transendothelial migration and chemotaxis in mouse cremaster muscle tissue are visualized with time-lapsed video photography and tracked with ImageJ.

Seguimiento de Rastreo de neutrófilos intraluminal, la migración transendotelial y la quimiotaxis de los tejidos por microscopía de vídeo intravital

The recruitment of circulating leukocytes from blood stream to the inflamed tissue is a crucial and complex process of inflammation1,2. In the ...

Intravital Imaging of the Mouse Thymus using 2-Photon Microscopy

Two-photon Microscopy (TPM) provides image acquisition in deep areas inside tissues and organs. In combination with the development of new stereotactic tools and surgical procedures, TPM becomes a powerful technique to identify "niches" inside organs and to document cellular "behaviors" in live animals. While intravital imaging provides information that best resembles the real cellular behavior inside the organ, it is both more laborious and technically demanding in terms of required equipment/procedures than alternative ex vivo imaging acquisition. Thus, we describe a surgical procedure and novel "stereotactic" organ holder that allows us to follow the movements of Foxp3+ cells within the thymus.
Foxp3 is the master regulator for the generation of regulatory T cells (Tregs). Moreover, these cells can be classified according to their origin: ie. thymus-differentiated Tregs are called "naturally-occurring Tregs" (nTregs), as opposed to peripherally-converted Tregs (pTregs). Although significant amount of research has been reported in the literature concerning the phenotype and physiology of these T cells, very little is known about their in vivo interactions with other cells. This deficiency may be due to the absence of techniques that would permit such observations. The protocol described in this paper provides a remedy for this situation.
Our protocol consists of using nude mice that lack an endogenous thymus since they have a punctual mutation in the DNA sequence that compromises the differentiation of some epithelial cells, including thymic epithelial cells. Nude mice were gamma-irradiated and reconstituted with bone marrows (BM) from Foxp3-KIgfp/gfp mice. After BM recovery (6 weeks), each animal received embryonic thymus transplantation inside the kidney capsule. After thymus acceptance (6 weeks), the animals were anesthetized; the kidney containing the transplanted thymus was exposed, fixed in our organ holder, and kept under physiological conditions for in vivo imaging by TPM. We have been using this approach to study the influence of drugs in the generation of regulatory T cells.

We have developed novel laboratory tools and protocols for intravital imaging acquisition of the thymus. Our technique should help in the identification of &#x201C;niches&#x201D; within the thymus where T cell development occurs.

Imagen intravital del timo de ratón utilizando 2-Photon Microscopy

Two-photon Microscopy (TPM) provides image acquisition in deep areas inside tissues and organs. In combination with the development of new stereotactic ...

Intravital Microscopy of the Spleen: Quantitative Analysis of Parasite Mobility and Blood Flow

The advent of intravital microscopy in experimental rodent malaria models has allowed major advances to the knowledge of parasite-host interactions 1,2. Thus, in vivo imaging of malaria parasites during pre-erythrocytic stages have revealed the active entrance of parasites into skin lymph nodes 3, the complete development of the parasite in the skin 4, and the formation of a hepatocyte-derived merosome to assure migration and release of merozoites into the blood stream 5. Moreover, the development of individual parasites in erythrocytes has been recently documented using 4D imaging and challenged our current view on protein export in malaria 6. Thus, intravital imaging has radically changed our view on key events in Plasmodium development. Unfortunately, studies of the dynamic passage of malaria parasites through the spleen, a major lymphoid organ exquisitely adapted to clear infected red blood cells are lacking due to technical constraints.
Using the murine model of malaria Plasmodium yoelii in Balb/c mice, we have implemented intravital imaging of the spleen and reported a differential remodeling of it and adherence of parasitized red blood cells (pRBCs) to barrier cells of fibroblastic origin in the red pulp during infection with the non-lethal parasite line P.yoelii 17X as opposed to infections with the P.yoelii 17XL lethal parasite line 7. To reach these conclusions, a specific methodology using ImageJ free software was developed to enable characterization of the fast three-dimensional movement of single-pRBCs. Results obtained with this protocol allow determining velocity, directionality and residence time of parasites in the spleen, all parameters addressing adherence in vivo. In addition, we report the methodology for blood flow quantification using intravital microscopy and the use of different colouring agents to gain insight into the complex microcirculatory structure of the spleen. 
Ethics statement
All the animal studies were performed at the animal facilities of University of Barcelona in accordance with guidelines and protocols approved by the Ethics Committee for Animal Experimentation of the University of Barcelona CEEA-UB (Protocol No DMAH: 5429). Female Balb/c mice of 6-8 weeks of age were obtained from Charles River Laboratories.

We show the method for performing intravital microscopy of the spleen using GFP transgenic malaria parasites and the quantification of parasite mobility and blood flow within this organ.

Microscopia intravital del bazo: Análisis cuantitativo de la movilidad del parásito y el flujo sanguíneo

The advent of intravital microscopy in experimental rodent malaria models has allowed major advances to the knowledge of parasite-host interactions 1,2. ...

Intravital Microscopy Imaging of the Liver following Leishmania Infection: An Assessment of Hepatic Hemodynamics

Intravital microscopy (IVM) is a powerful optical imaging technique that has made possible the visualization, monitoring and quantification of various biological events in real time and in live animals. This technology has greatly advanced our understanding of physiological processes and pathogen-mediated phenomena in specific organs.
In this study, IVM is applied to the mouse liver and protocols are designed to image in vivo the circulatory system of the liver and measure red blood cell (RBC) velocity in individual hepatic vessels. To visualize the different vessel subtypes that characterize the hepatic organ and perform blood flow speed measurements, C57Bl/6 mice are intravenously injected with a fluorescent plasma reagent that labels the liver-associated vasculature. IVM enables in vivo, real time, measurement of RBC velocity in a specific vessel of interest. Establishing this methodology will make it possible to investigate liver hemodynamics under physiological and pathological conditions. Ultimately, this imaging-based methodology will be important for studying the influence of L. donovani infection&#160;on hepatic hemodynamics.
This method can be applied to other infectious models and mouse organs and might be further extended to pre-clinical testing of a drug&#8217;s effect on inflammation by quantifying its effect on blood flow.

Intravital Microscopy Imaging of the Liver following Leishmania Infection: An Assessment of Hepatic Hemodynamics

This article reports on a detailed method for the dynamic measurement and quantification of blood flow velocity within individual blood vessels of the mouse liver vasculature using intravital microscopy imaging in combination with a specific methodology for image acquisition and analysis.

Microscopia intravital de imágenes del hígado después<em&gt; Leishmania</em&gt; Infección: Una Evaluación de Hemodinámica hepática

Intravital microscopy (IVM) is a powerful optical imaging technique that has made possible the visualization, monitoring and quantification of various ...

Intravital Microscopy of Leukocyte-endothelial and Platelet-leukocyte Interactions in Mesenterial Veins in Mice

Intravital microscopy is a method that can be used to investigate different processes in different regions and vessels in living animals. In this protocol, we describe intravital microscopy of mesentery veins. This can be performed in a short period of time with reproducible results showing leukocyte-endothelial interactions in vivo. We describe an inflammatory setting after LPS challenge of the endothelium. But in this model one can apply many different types of inflammatory conditions, like bacterial, chemical or biological and investigate the administration of drugs and their direct effects on the living animal and its impact on leukocyte recruitment. This protocol has been applied successfully to a number of different treatments of mice and their effects on inflammatory response in vessels. Herein, we describe the visualization of leukocytes and platelets by fluorescently labeling these with rhodamine 6G. Additionally, any specific imaging can be performed using targeted fluorescently labeled molecules.

This simplified application of intravital microscopy of mesentery veins in mice can be used in different models of inflammation to observe leukocyte-endothelial and platelet-leukocyte interactions.

Interacciones intravital microscopía de leucocitos endoteliales y plaquetas de leucocitos en mesenterial venas en ratones

Intravital microscopy is a method that can be used to investigate different processes in different regions and vessels in living animals. In this ...

Imaging Neutrophils and Monocytes in Mesenteric Veins by Intravital Microscopy on Anaesthetized Mice in Real Time

Efficient immune response is dependent on rapid mobilization of blood leukocytes to the site of infection or injury. Investigating leukocyte migration in vivo is crucial for understanding the molecular basis of leukocyte transendothelial migration and interaction with vascular endothelium. One powerful approach involves intravital microscopy on transgenic mice expressing fluorescent proteins in cells of interest.
Here we present a protocol for imaging monocytes and neutrophils in the CX3CR1gfp/wt mouse i.v. injected with orange dye-labeled neutrophils with an inverted confocal microscope. Time-lapse movies gathered from 30 min&#160;to several hours of imaging allow the analysis of leukocyte behavior in mesenteric veins under both steady state and inflammatory conditions. We also describe the steps to locally induce blood vessel inflammation with TLR2/TLR1 agonist Pam3SK4 and monitor the subsequent recruitment of neutrophils and monocytes.
The presented technique can also be used to monitor other populations of leukocytes and investigate molecules implicated in leukocyte recruitment or trafficking using other stimuli or transgenic mice.

We detail a protocol to monitor the behavior of neutrophils and monocytes in mesenteric veins under steady state and inflammatory conditions using intravital confocal microscopy on anaesthetized mice.

Imaging neutrófilos y monocitos en mesentérica venas por Microscopia intravital en ratones anestesiados en Tiempo Real

Efficient immune response is dependent on rapid mobilization of blood leukocytes to the site of infection or injury. Investigating leukocyte migration in ...

Swab Sampling Method for the Detection of Human Norovirus on Surfaces

Human noroviruses are a leading cause of epidemic and sporadic gastroenteritis worldwide. Because most infections are either spread directly via the person-to-person route or indirectly through environmental surfaces or food, contaminated fomites and inanimate surfaces are important vehicles for the spread of the virus during norovirus outbreaks.
We developed and evaluated a protocol using macrofoam swabs for the detection and typing of human noroviruses from hard surfaces. Compared with fiber-tipped swabs or antistatic wipes, macrofoam swabs allow virus recovery (range 1.2-33.6%) from toilet seat surfaces of up to 700 cm2. The protocol includes steps for the extraction of the virus from the swabs and further concentration of the viral RNA using spin columns. In total, 127 (58.5%) of 217 swab samples that had been collected from surfaces in cruise ships and long-term care facilities where norovirus gastroenteritis had been reported tested positive for GII norovirus by RT-qPCR. Of these 29 (22.8%) could be successfully genotyped. In conclusion, detection of norovirus on environmental surfaces using the protocol we developed may assist in determining the level of environmental contamination during outbreaks as well as detection of virus when clinical samples are not available; it may also facilitate monitoring of effectiveness of remediation strategies.

A macrofoam based sampling methodology was developed and evaluated for the detection and quantification of norovirus on environmental hard surfaces.

Método de muestreo hisopo para la Detección de norovirus humano en superficies

Human noroviruses are a leading cause of epidemic and sporadic gastroenteritis worldwide. Because most infections are either spread directly via the ...

Preparation of Murine Submandibular Salivary Gland for Upright Intravital Microscopy

The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, including cell biology, oncology, dentistry, and immunology. The SMG is an exocrine gland comprised of secretory epithelial cells, myofibroblasts, endothelial cells, nerves, and extracellular matrix. Dynamic cellular processes in the rat and mouse SMG have previously been imaged, mostly using inverted multi-photon microscope systems. Here, we describe a straightforward protocol for the surgical preparation and stabilization of the murine SMG in anesthetized mice for in vivo imaging with upright multi-photon microscope systems. We present representative intravital image sets of endogenous and adoptively transferred fluorescent cells, including the labeling of blood vessels or salivary ducts and second harmonic generation to visualize fibrillar collagen. In sum, our protocol allows for surgical preparation of mouse salivary glands in upright microscopy systems, which are commonly used for intravital imaging in the field of immunology.

We describe a protocol to surgically expose and stabilize the murine submandibular salivary gland for intravital imaging using upright intravital microscopy. This protocol is easily adaptable to other exocrine glands of the head and neck region of mice and other small rodents.

Preparación de glándula salival submaxilar murino para la microscopia Intravital vertical

The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, ...

Imaging Cell Interaction in Tracheal Mucosa During Influenza Virus Infection Using Two-photon Intravital Microscopy

The analysis of cell-cell or cell-pathogen interaction in vivo is an important tool to understand the dynamics of the immune response to infection. Two-photon intravital microscopy (2P-IVM) allows the observation of cell interactions in deep tissue in living animals, while minimizing the photobleaching generated during image acquisition. To date, different models for 2P-IVM of lymphoid and non-lymphoid organs have been described. However, imaging of respiratory organs remains a challenge due to the movement associated with the breathing cycle of the animal.
Here, we describe a protocol to visualize in vivo immune cell interactions in the trachea of mice infected with influenza virus using 2P-IVM. To this purpose, we developed a custom imaging platform, which included the surgical exposure and intubation of the trachea, followed by the acquisition of dynamic images of neutrophils and dendritic cells (DC) in the mucosal epithelium. Additionally, we detailed the steps needed to perform influenza intranasal infection and flow cytometric analysis of immune cells in the trachea. Finally, we analyzed neutrophil and DC motility as well as their interactions during the course of a movie. This protocol allows for the generation of stable and bright 4D images necessary for the assessment of cell-cell interactions in the trachea.

In this study, we present a protocol to perform two-photon intravital imaging and cell interaction analysis in the murine tracheal mucosa after infection with influenza virus. This protocol will be relevant for researchers studying immune cell dynamics during respiratory infections.

Proyección de imagen de interacción de células en Mucosa traqueal durante la infección del Virus de la Influenza usando microscopia Intravital de dos fotones

The analysis of cell-cell or cell-pathogen interaction in vivo is an important tool to understand the dynamics of the immune response to infection. ...