Ringraziamo R. Heintzmann per discussioni fruttuose durante lo sviluppo di un approccio strisce-illuminazione, K. Rajewsky e A. Haberman per fornire C57BL / 6 B1-8 GFP topi transgenici. Riconosciamo la Deutsche Forschungsgemeinschaft in concessione NI1167/3-1 (a RN), HA5354/4-1 e SFB633, A15 progetto (AEH), la Charité in concessione Rahel-Hirsch borsa di studio (per RN) per il sostegno finanziario. In particolare, ci riconosciamo la rete JIMI per le discussioni fruttuose e supporto infrastrutturale

<ol>
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W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-photon+laser+scanning+fluorescence+microscopy.">Two-photon laser scanning fluorescence microscopy.</a> Science. 248 (4951), 73-76 (1990).</li><li>Siffrin, V., 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=In+vivo+imaging+of+partially+reversible+th17+cell-induced+neuronal+dysfunction+in+the+course+of+encephalomyelitis.">In vivo imaging of partially reversible th17 cell-induced neuronal dysfunction in the course of encephalomyelitis.</a> Immunity. 33 (3), 424-436 (2010).</li><li>Esplugues, E., 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=Control+of+Th17+cells+occurs+in+the+small+intestine.">Control of Th17 cells occurs in the small intestine.</a> Nature. 475 (7357), 514-518 (2011).</li><li>Hauser, A. E., 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=Definition+of+germinal-center+B+cell+migration+in+vivo+reveals+predominant+intrazonal+circulation+patterns.">Definition of germinal-center B cell migration in vivo reveals predominant intrazonal circulation patterns.</a> Immunity. 26 (5), 655-667 (2007).</li><li>Cahalan, M. D., Parker, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Choreography+of+cell+motility+and+interaction+dynamics+imaged+by+two-photon+microscopy+in+lymphoid+organs.">Choreography of cell motility and interaction dynamics imaged by two-photon microscopy in lymphoid organs.</a> Annu. Rev. 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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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N., Cui, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Superpenetration+optical+microscopy+by+iterative+multiphoton+adaptive+compensation+technique.">Superpenetration optical microscopy by iterative multiphoton adaptive compensation technique.</a> Proc. Natl. Acad. Sci. USA. 109 (22), 8434-8439 (2012).</li><li>Ji, N., Milkie, D. E., Betzig, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adaptive+optics+via+pupil+segmentation+for+high+resolution+imaging+in+biological+tissues.">Adaptive optics via pupil segmentation for high resolution imaging in biological tissues.</a> Nat. Methods. 7, 141-147 (2009).</li><li>Lu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Super-resolution+laser+scanning+microscopy+through+spatiotemporal+modulation.">Super-resolution laser scanning microscopy through spatiotemporal modulation.</a> Nano Lett. 9 (11), 3883-3889 (2009).</li><li>Andresen, V., 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=High-resolution+intravital+microscopy.">High-resolution intravital microscopy.</a> PLoS ONE. 7 (12), (2012).</li><li>Debarre, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adaptive+optics+for+structured-illumination.">Adaptive optics for structured-illumination.</a> Opt. Exp. 16 (13), 9290-9305 (2008).</li></ol>

Volker Andresen è azionista di LaVision Biotec GmbH, Bielefeld, Germania. Gli altri autori non hanno conflitti di interesse.

Lo scopo di imaging ottico intravital è di visualizzare dinamicamente e funzionalmente motilità e interazioni cellulari per comprendere tessuto e funzione degli organi in salute e malattia 5. Il più potente tecnologia per ottenere questo, multi-fotone microscopia a scansione laser, deve ancora superare le limitazioni relative a onda distorsioni anteriori, dispersione, acquisizione lenta, photobleaching e photodamage, che limitano la sua risoluzione spaziale, contrasto nonché la sua risoluzione temporale ....

Due fotoni microscopia a scansione laser (TPLSM), con i suoi vantaggi per l&#39;imaging dei tessuti profondi relativi a infrarossi ultra-short di eccitazione impulsiva 1, ha rivoluzionato il nostro punto di vista sui processi vitali a livello di singola cellula rivelando motilità e l&#39;interazione di vari modelli sottopopolazioni di cellule negli animali viventi 2-5. Tuttavia, la tecnologia attuale è ancora insufficiente a chiarire i meccanismi di funzionamento degli organi e disfunzioni come prerequisito per lo sviluppo di nuove strategie terapeutiche, in quanto rende solo informazioni sparse sulle basi molecolari della risposta cellulare all&#39;interno dei tessuti nella salute e nella malattia. La tecnologia attuale permette solo una finestra spaziale di poche centinaia di micron dovuta alla dispersione ed effetti di distorsione d&#39;onda anteriori risoluzione spaziale e rapporto segnale-rumore 6, che sono particolarmente evidenti nel tessuto altamente compatto di animali adulti. Questi effetti di distorsione anteriori di scattering e onda sono dovute ad un un ambiente altamente eterogeneod anisotropo distribuzione dell&#39;indice di rifrazione in tessuto, che porta in un primo passo per una profondità dipendente deterioramento della risoluzione spaziale 3D e infine alla perdita totale del segnale proveniente dai fotoni di eccitazione balistici, cioè la perdita di rapporto segnale-rumore. In termini di bioscientific e applicazioni biomediche tessuti profondi, questo significa che la tecnologia attuale è in grado di rivelare inequivocabilmente comunicazione cellulare perché scarsa risoluzione comporterebbe interazioni falsamente positivi mentre la riduzione del rapporto segnale-rumore causerebbe il sistema trascurare alcuni interazioni tra strutture dim. Per rilevare inequivocabilmente interazioni cellulari in modo dinamico, una risoluzione spaziale elevata è necessario migliorare la profondità all&#39;interno del tessuto. Le potenti tecniche nanoscopia attualmente introdotte sulla base di algoritmi numerici particolari, ad esempio approcci struttura illuminazione, sulla deplezione del primo stato eccitato, ad esempio </em&gt; STED, RESOLFT, o sulla localizzazione molecola, ad esempio dSTORM, PALM, hanno trovato numerose applicazioni in cellule fissate e in colture cellulari Live 7. Tuttavia, al fine di estendere queste applicazioni per sezioni di tessuto, tessuto vivente e organismi abbiamo ancora bisogno di superare le gravi difficoltà tecniche. Eccitazione a due fotoni STED con differenti lunghezze d&#39;onda e con una singola lunghezza d&#39;onda (sw2PE-STED) per eccitazione e di emissione stimolata è stata applicata per migliorare la risoluzione laterale in fettine cerebrali 8 o artificiali in matrici di celle incorporate 9, rispettivamente, allo stesso risoluzione assiale TPLSM standard. Utilizzando un fotone STED, le dinamiche di spine dendritiche potrebbero essere esposte alla superficie della corteccia cerebrale (fino a 10-15 micron di profondità) in un topo vivente Thy1 EGFP con una risoluzione di 67 nm 10. Uno strumento versatile per la biologia dello sviluppo è fornito dalla multifocale microscopio strutturato-illuminazione, che fornisce duplice migliorato 2Drisoluzione. Tuttavia, questa tecnica può essere utilizzata solo in organismi con una bassa propensione di diffusione della luce come embrioni di pesce zebra 11. Tuttavia, nessuna di queste tecniche può essere applicata nel tessuto altamente dispersione di animali adulti in diverse centinaia di micrometri, che sono modelli cruciali per la ricerca biomedica e clinica delle malattie con insorgenza dopo la nascita. Indipendentemente dal approssimazione utilizzato per calcolare la forma del fronte d&#39;onda a diffrazione limitata, cioè la funzione del punto di diffusione (PSF), dopo la focalizzazione attraverso una lente, la larghezza della PSF lungo l&#39;asse ottico (risoluzione assiale) è almeno tre volte più grande la larghezza PSF perpendicolare all&#39;asse ottico (risoluzione laterale) 12. Onda distorsioni anteriori dei diversi ordini quantificati mediante coefficienti di Zernike modificato notevolmente la forma del fronte d&#39;onda dell&#39;onda elettromagnetica focalizzata nella rappresentazione del tessuto profondo che porta a molto più grandi PSF, specialmente lungo l&#39;otticaal all&#39;asse 13-15. Quindi, entrambe le leggi di diffrazione e gli effetti di distorsione del fronte d&#39;onda indicano la risoluzione lungo l&#39;asse ottico come il fattore limitante nella rappresentazione dei tessuti profondi. Considerando che le tecniche nanoscopia si concentrano sulla lotta contro i limiti di diffrazione solo, è necessaria una tecnologia che migliora la risoluzione assiale e il contrasto contrastando sia la diffrazione ed effetti di distorsione delle onde-front per imaging ad alta risoluzione intravitale. Idealmente, questa tecnica dovrebbe essere anche abbastanza veloce per consentire il monitoraggio delle dinamiche cellulari. La correzione in tempo reale di aberrazioni di FPF e la perdita di contrasto utilizzando ottiche adattive in TPLSM è stato ampiamente studiato e migliorato negli ultimi dieci anni 13,14,16-18 ed è quindi la scelta migliore attualmente disponibile che porta ad una migliore gestione dell&#39;eccitazione balistico Fotoni 14. Ancora, a causa del fatto che la maggior onda correzione anteriore approcci utilizzati in ottica adattiva sono iterativo e che ettarove essere ripetuto per piccole aree (pochi 10 x 10 micron 2) a causa dell&#39;elevata eterogeneità dell&#39;indice di rifrazione nel tessuto, la velocità di acquisizione è significativamente inferiore a quello necessario per la motilità cellulare imaging e comunicazione. Inoltre, il limite fisico in adattativi ottica migliorata TPLSM è ancora determinato dalla diffrazione. Modulazione spaziale di illuminamento (SPIN) e modulazione temporale sul lato rivelazione (SPADE) sono stati teoricamente proposto da applicare alla microscopia a scansione laser per migliorare la risoluzione. La loro applicazione pratica nel campo dell&#39;imaging intravitale resta da dimostrare 19. Presi insieme, vi è una forte domanda per lo sviluppo di tecnologie che migliorano la risoluzione per l&#39;imaging del tessuto profondo nel vivere animali adulti. In questo lavoro, raggiungiamo la modulazione spaziale del modello di eccitazione controllando il processo di scansione in multi-beam strisce-illuminazione multi-fotone laser-smicroscopia conserviera (MB-SI-MPLSM) 20. Contrariamente agli approcci illuminazione strutturati, in cui la sezione di eccitazione traversa è spazialmente modulata, usiamo solo il processo di scansione per ottenere la modulazione spaziale della eccitazione. Espandendo l&#39;eccitazione di una lunghezza d&#39;onda, siamo in grado di migliorare sia la risoluzione spaziale e rapporto segnale-rumore in tessuto profondo fortemente diffondenti di tessuto (per esempio linfonodi, cammino libero-dispersione 47 micron 6), indipendentemente dalla ottica segnale non lineare si rileva, ad esempio, fluorescenza, generazione di seconda armonica o altra frequenza di miscelazione fenomeno. Usando questo approccio a lunghezze d&#39;onda di eccitazione fino a 900 nm, possiamo dinamicamente immagine strutture proteiche cellulare su scala di poche molecole in centri germinali dei linfonodi del mouse. Così, si può visualizzare meglio l&#39;interazione tra unità di antigene trasportano sulla superficie delle cellule follicolari dendritiche e cellule B nel processo di tastatura antiGen durante la risposta immunitaria in organi linfoidi secondari.

<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

Monitoraggio della comunicazione cellulare da intravital tessuto profondo microscopia multi-fotone è la chiave per comprendere il destino delle cellule immunitarie all&#39;interno di campioni di tessuti spessi e gli organi in salute e malattia. Controllando il modello di scansione in microscopia multi-fotone e l&#39;applicazione di algoritmi numerici appropriati, abbiamo sviluppato un approccio strisce-illuminazione, che ha consentito di ottenere 3 volte migliore risoluzione assiale e miglior rapporto segnale-rumore, cioè contrasto, in più di 100 micron di profondità il tessuto all&#39;interno altamente dispersione del tessuto degli organi linfoidi rispetto allo standard di microscopia multi-fotone. La velocità di acquisizione nonché effetti Fotodecolorazione e fotodanneggiamento erano simili alla tecnica basata fotomoltiplicatore standard, mentre la profondità di immagine era leggermente inferiore a causa dell&#39;uso di rilevatori di campo. Utilizzando l&#39;approccio strisce-illuminazione, siamo in grado di osservare le dinamiche dei depositi complessi immuni sulle cellule follicolari dendritiche secondarie ̵1; sul livello di alcune molecole proteiche in centri germinativi.

Risoluzione spaziale nei linfonodi Le dimensioni della funzione del punto di diffusione efficace (EPSF) corrispondono alla risoluzione spaziale di un microscopio 12. Abbiamo misurato questa funzione tre dimensionale acquisendo il segnale di seconda generazione armoniche di fibre collagene nei linfonodi dal nostro MB-SI-TPLSM rispetto alle stabiliti tecniche di microscopia a scansione laser a due fotoni, cioè TPLSM rilevamento di campo (mediante telecamere CCD) e TPLSM rilev...

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

Ad alta risoluzione intravital immagini con maggiore contrasto fino a 120 micron di profondità in linfonodi di topi adulti si ottiene spazialmente modulando il pattern di eccitazione di un microscopio a due fotoni multifocale. In 100 micron di profondità abbiamo misurato risoluzioni di 487 nm (laterali) e 551 nm (assiale), eludendo così dispersione e diffrazione limiti.

Altamente Risolto intravitale Striped-illuminazione Microscopia dei Centri Germinal

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 Views.  Leibniz Institute.  Ad alta risoluzione intravital immagini con maggiore contrasto fino a 120 micron di profondità in linfonodi di topi adulti si ottiene spazialmente modulando il pattern di eccitazione di un microscopio a due fotoni multifocale. In 100 micron di profondità abbiamo misurato risoluzioni di 487 nm (laterali) e 551 nm (assiale), eludendo così dispersione e diffrazione limiti. 

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 intravitale del linfonodo inguinale

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 ...

Ricerca

Immunologia e infezioni

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.

Monitoraggio Crawling neutrofili intraluminale, migrazione e chemiotassi transendoteliale in tessuto al microscopio video intravitale

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.

Imaging intravitale del Timo mouse utilizzando 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 intravitale della Milza: analisi quantitativa della mobilità Parasite e del flusso sanguigno

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.

Intravitale Microscopia Imaging del Fegato seguente<em&gt; Leishmania</em&gt; Infezione: Valutazione della epatiche Emodinamica

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.

Interazioni intravitale Microscopia di leucociti-endoteliali e piastrine-leucociti in Mesenterial Vene Mice

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 neutrofili e monociti in mesenterica Veins intravitale Microscopia su topi anestetizzati in tempo reale

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.

Tampone Metodo di campionamento per la rilevazione di Norovirus umana sulle superfici

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.

Preparazione della ghiandola salivare sottomandibolare murino per microscopia Intravital verticale

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.

La formazione immagine interazione cellula nella Mucosa trachea durante l'infezione da Virus influenzale usando la microscopia Intravital due-fotone

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. ...