Name: cortical actin flow in t cells quantified by spatio-temporal image correlation spectroscopy of structured illumination microscopy data
Uploaded: 2015-12-17T15:00:00
Description: Watch this Scientific Journal Video about Cortical Actin Flow in T Cells Quantified by Spatio-temporal Image Correlation Spectroscopy of Structured Illumination Microscopy Data at JoVE.com

D.M.O. acknowledges European Research Council grant No. 337187 and the Marie-Curie Career Integration Grant No. 334303. P.W.W. acknowledges the Natural Sciences and Engineering Research Council of Canada's Discovery Grant program.

Note: Stages 1 and 2 take place before the day of imaging; ensure all media and supplements to be used before or on the day of imaging are equilibrated. Equilibration is achieved through warming of media and supplements to 37 &#176;C in an incubator set to 5% CO2. All cell culture work and coverslip plating steps take place in sterile conditions under a laminar flow hood.
1. Cell Transfection
<ol>
	<li>Transfect the T cells to be imaged 24 hr before the experiment with a plasmid e...

<ol>
	<li>Monks, C., Freiberg, B., Kupfer, H., Sciaky, N., Kupfer, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+segregation+of+supramolecular+activation+clusters+in+T+cells.">Three-dimensional segregation of supramolecular activation clusters in T cells.</a> Nature. 395, 82-86 (1998).</li><li>Lanzavecchia, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antigen-specific+interaction+between+T+and+B+cells.">Antigen-specific interaction between T and B cells.</a> Nature. 314, 537-539 (1985).</li><li>Grakoui, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+immunological+synapse:+a+molecular+machine+controlling+T+cell+activation.">The immunological synapse: a molecular machine controlling T cell activation.</a> Science. 285 (5425), 221-227 (1999).</li><li>Delon, J., Bercovici, N., Liblau, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imaging+antigen+recognition+by+naive+CD4++T+cells:+compulsory+cytoskeletal+alterations+for+the+triggering+of+an+intracellular+calcium+response.">Imaging antigen recognition by naive CD4+ T cells: compulsory cytoskeletal alterations for the triggering of an intracellular calcium response.</a> European journal of Immunology. 28 (2), 716-729 (1998).</li><li>Varma, R., Campi, G., Yokosuka, T., Saito, T., Dustin, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T+Cell+Receptor-Proximal+Signals+Are+Sustained+in+Peripheral+Microclusters+and+Terminated+in+the+Central+Supramolecular+Activation+Cluster.">T Cell Receptor-Proximal Signals Are Sustained in Peripheral Microclusters and Terminated in the Central Supramolecular Activation Cluster.</a> Immunity. 25 (1), 117-127 (2006).</li><li>Rust, M. J., Bates, M., Zhuang, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sub-diffraction-limit+imaging+by+stochastic+optical+reconstruction+microscopy+(STORM).">Sub-diffraction-limit imaging by stochastic optical reconstruction microscopy (STORM).</a> Nature methods. 3, 793-796 (2006).</li><li>Betzig, 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=Imaging+intracellular+fluorescent+proteins+at+nanometer+resolution.">Imaging intracellular fluorescent proteins at nanometer resolution.</a> Science. 313 (5793), 1642-1645 (2006).</li><li>Klar, T. A., Jakobs, S., Dyba, M., Egner, A., Hell, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescence+microscopy+with+diffraction+resolution+barrier+broken+by+stimulated+emission.">Fluorescence microscopy with diffraction resolution barrier broken by stimulated emission.</a> Proceedings of the National Academy of Sciences. 97 (15), 8206-8210 (2000).</li><li>Gustafsson, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surpassing+the+lateral+resolution+limit+by+a+factor+of+two+using+structured+illumination+microscopy.">Surpassing the lateral resolution limit by a factor of two using structured illumination microscopy.</a> Journal of Microscopy. 198 (2), 82-87 (2000).</li><li>Hebert, B., Costantino, S., Wiseman, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatiotemporal+image+correlation+spectroscopy+(STICS)+theory,+verification,+and+application+to+protein+velocity+mapping+in+living+CHO+cells.">Spatiotemporal image correlation spectroscopy (STICS) theory, verification, and application to protein velocity mapping in living CHO cells.</a> Biophysical Journal. 88 (5), 3601-3614 (2005).</li><li>Ashdown, G. W., Cope, A., Wiseman, P. W., Owen, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+Flow+Quantified+beyond+the+Diffraction+Limit+by+Spatiotemporal+Image+Correlation+of+Structured+Illumination+Microscopy+Data.">Molecular Flow Quantified beyond the Diffraction Limit by Spatiotemporal Image Correlation of Structured Illumination Microscopy Data.</a> Biophysical Journal. 107 (9), 21-23 (2014).</li><li>Brown, C. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+the+integrin-actin+linkage+using+high-resolution+protein+velocity+mapping.">Probing the integrin-actin linkage using high-resolution protein velocity mapping.</a> Journal of Cell Science. 19 (24), 5204-5214 (2006).</li><li>Yi, J., Xufeng, S. W., Crites, T., Hammer, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Actin+retrograde+flow+and+actomyosin+II+arc+contraction+drive+receptor+cluster+dynamics+at+the+immunological+synapse+in+Jurkat+T+cells.">Actin retrograde flow and actomyosin II arc contraction drive receptor cluster dynamics at the immunological synapse in Jurkat T cells.</a> Molecular Biology of the Cell. 23 (5), 834-852 (2012).</li><li>Watanabe, N., Mitchison, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-molecule+speckle+analysis+of+actin+filament+turnover+in+lamellipodia.">Single-molecule speckle analysis of actin filament turnover in lamellipodia.</a> Science. 8 (5557), 1083-1086 (2002).</li></ol>

This technique will allow researchers to image and quantify previously unresolvable details in cells expressing fluorescence. In our results we show that F-actin flows in a symmetrical fashion from the cell periphery towards the cell center in the T cell IS. These findings are consistent with previous results from 1D line profile kymograph data13 and extend the capacity of analysis to 2D and super-resolution data.
The presented technique is a progression from kymograph imaging which...

The goal of the experiment is to image and characterize the molecular flow of filamentous- (F-) actin in living T cells, beyond the diffraction limit in order to establish flow direction and magnitude during immunological synapse (IS) formation. This technique will be carried out using a structured illumination microscope (SIM) in total internal reflection fluorescence (TIRF) mode, imaging Jurkat T-cells forming an artificial synapse on activating coverslips coated with anti-CD3- and anti-CD28 antibodies. The IS forms between a T cell and its target; an antigen presenting cell (APC) upon T cell receptor (TCR) activation1,2. As this is the first step in determining whether the adaptive immune system generates an immune response to an infection, the consequences of incorrect responsiveness to stimuli can cause a number of diseases. The importance of the T cell-APC interaction is well documented, however, the role(s) of the mature IS after initial TCR signal internalization are yet to be fully understood.
As the cytoskeleton is thought to aid two processes linked to TCR activation (the movement of molecules at the plasma membrane and the control of signaling molecules dependent on the actin cytoskeleton3,4 ), understanding how the cytoskeleton rearranges spatially and temporally will elucidate the steps of molecular reorganization during synapse formation. The retrograde flow of F-actin is thought to corral TCR clusters towards the center of the immunological synapse, this translocation is believed to be vital for signal cessation and recycling; aiding the fine balance of T cell activation5.
While standard fluorescence microscopy is a flexible tool that continues to provide insight about many biological events including cell-cell interactions, it is limited by the system&#39;s ability to accurately resolve multiple fluorophores residing closer than the diffraction limit (&#8776;200 nm) of each other. As many molecular events within cells involve dense populations of molecules and exhibit dynamic rearrangement either in quiescence or upon specific stimulation, conventional light microscopy does not provide the full picture.
The use of super resolution imaging has allowed researchers to circumvent the diffraction limit using a variety of techniques. Single molecule localization microscopy (SMLM) such as PALM and STORM6,7 has the ability to resolve the location of molecules up to a precision of around 20 nm, however, these techniques rely on long acquisition times, building up an image over many frames. Generally this requires samples to be fixed or for structures to exhibit low mobility so single fluorophores are not misinterpreted as multiple points. While stimulated emission depletion (STED) imaging allows super-resolution through very selective confocal excitation8, the required scanning approach can be slow over whole cell fields of view. STED also demonstrates significant phototoxicity for higher resolutions due to the increase in power of the depletion beam.
Structured illumination microscopy (SIM9) provides an alternative to these methods, capable of doubling the resolution of a standard fluorescence microscope and is more compatible with live cell imaging than current SMLM techniques. It uses lower laser powers, on a wide-field system for whole-cell fields of view; providing increased acquisition speeds, and is compatible with standard fluorophore labelling. The wide-field nature of SIM also permits the utilization of total internal reflection fluorescence (TIRF) for highly selective excitation, with penetration depths in the axial dimension of &#60;100 nm.
Image correlation spectroscopy (ICS) is a method of correlating fluctuations in fluorescence intensity. An evolution of ICS; Spatio-temporal image correlation spectroscopy (STICS10) correlates intracellular fluorescent signals in time and space. By correlating pixel intensities with surrounding pixels in lagging frames via a correlation function, information is gained regarding flow speeds and directionality. To ensure static objects do not interfere with the STICS analysis, an immobile object filter is implemented, which works by subtracting a moving average of the pixel intensities.
The technique presented here is believed to be the first demonstration of image correlation spectroscopy being applied to super-resolution microscopy data to quantify the molecular flow in live cells11. This method improves on diffraction-limited imaging of F-actin flow via STICS analysis12 and would suit researchers who wish to determine two-dimensional molecular flow in live cells, from data acquired at spatial resolutions beyond the diffraction limit of light.

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			<td height="20" style="height:20px;width:271px;">Consumables:</td>
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			<td height="20" style="height:20px;">Jurkat E6.1 cells</td>
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			<td>ATTC TIB-152</td>
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			<td height="20" style="height:20px;">RPMI</td>
			<td>Life Technologies</td>
			<td>21875-091</td>
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			<td height="20" style="height:20px;">FBS</td>
			<td>Sigma</td>
			<td>F7524-500ML</td>
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			<td height="20" style="height:20px;">Penicillin-Strepromycin&#160;</td>
			<td>Life Technologies</td>
			<td>15140-122</td>
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			<td height="20" style="height:20px;">HBSS</td>
			<td>&#160;Life Technologies</td>
			<td>14025-050</td>
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			<td height="20" style="height:20px;">HEPES</td>
			<td>Life Technologies</td>
			<td>15630-056</td>
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		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">#1.5 8-well Labtek coverslips</td>
			<td>NUNC, Labtek</td>
			<td>155409</td>
			<td></td>
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			<td height="20" style="height:20px;">LifeAct GFP construct</td>
			<td>Ibidi</td>
			<td>60101</td>
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			<td height="20" style="height:20px;">OptiMem</td>
			<td>Life Technologies</td>
			<td>51985-042</td>
			<td></td>
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			<td height="20" style="height:20px;">anti-CD3</td>
			<td>Cambridge Bioscience</td>
			<td>317315</td>
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			<td height="20" style="height:20px;">anti-CD28</td>
			<td>BD Bioscience / Insight Biotechnology</td>
			<td>555725</td>
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			<td height="20" style="height:20px;">PBS</td>
			<td>Life Technologies</td>
			<td>20012-019</td>
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			<td height="20" style="height:20px;">Lens oil</td>
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			<td height="20" style="height:20px;">Name</td>
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			<td height="20" style="height:20px;">Equipment:</td>
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			<td></td>
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		<tr height="20">
			<td height="20" style="height:20px;">Gene Pulsar Xcell System</td>
			<td>BioRad</td>
			<td>165-2660</td>
			<td></td>
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		<tr height="20">
			<td height="20" style="height:20px;">Cuvette (0.4cm)</td>
			<td>BioRad</td>
			<td>165-2088</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Centrifuge (5810R)</td>
			<td>Eppendorf&#160;</td>
			<td>5805 000.327</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Centrifuge (Heraeus)</td>
			<td>Biofuge pico</td>
			<td>75003235</td>
			<td></td>
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		<tr height="20">
			<td height="20" style="height:20px;">6 well plate</td>
			<td>Corning</td>
			<td>3516</td>
			<td></td>
		</tr>
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			<td height="20" style="height:20px;">Stage-top incubator</td>
			<td>Tokai Hit</td>
			<td>INUH-TIZSH</td>
			<td></td>
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		<tr height="20">
			<td height="20" style="height:20px;">Nikon N-SIM microscope</td>
			<td>Nikon</td>
			<td>Contact company</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Nikon Analyse software</td>
			<td>Nikon</td>
			<td>Contact company</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Incubator (190D)</td>
			<td>LEEC</td>
			<td>Contact company</td>
			<td></td>
		</tr>
	</tbody>
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cortical actin flow in t cells quantified by spatio-temporal image correlation spectroscopy of structured illumination microscopy data

Filamentous-actin plays a crucial role in a majority of cell processes including motility and, in immune cells, the formation of a key cell-cell interaction known as the immunological synapse. F-actin is also speculated to play a role in regulating molecular distributions at the membrane of cells including sub-membranous vesicle dynamics and protein clustering. While standard light microscope techniques allow generalized and diffraction-limited observations to be made, many cellular and molecular events including clustering and molecular flow occur in populations at length-scales far below the resolving power of standard light microscopy. By combining total internal reflection fluorescence with the super resolution imaging method structured illumination microscopy, the two-dimensional molecular flow of F-actin at the immune synapse of T cells was recorded. Spatio-temporal image correlation spectroscopy (STICS) was then applied, which generates quantifiable results in the form of velocity histograms and vector maps representing flow directionality and magnitude. This protocol describes the combination of super-resolution imaging and STICS techniques to generate flow vectors at sub-diffraction levels of detail. This technique was used to confirm an actin flow that is symmetrically retrograde and centripetal throughout the periphery of T cells upon synapse formation.

Microscope settings
After successfully achieving all steps the researcher will have accomplished structured illumination (SIM) imaging of F-actin flow in a T cell synapse (Video 1), and quantified this molecular flow by spatio-temporal image correlation spectroscopy (Figure 411). Before recording images, ensure the sample illumination is uniform across the nine raw images and that structured illuminat...

Watch this Scientific Journal Video about Cortical Actin Flow in T Cells Quantified by Spatio-temporal Image Correlation Spectroscopy of Structured Illumination Microscopy Data at JoVE.com

Cortical Actin Flow in T Cells Quantified by Spatio-temporal Image Correlation Spectroscopy of Structured Illumination Microscopy Data

To investigate flow velocities and directionality of filamentous-actin at the T cell immunological synapse, live-cell super-resolution imaging is combined with total internal reflection fluorescence and quantified with spatio-temporal image correlation spectroscopy.

Filamentous-actin plays a crucial role in a majority of cell processes including motility and, in immune cells, the formation of a key cell-cell ...

cortical-actin-flow-t-cells-quantified-spatio-temporal-image

Research

JoVE Journal

Immunology and Infection

Retroviral Transduction of T-cell Receptors in Mouse T-cells

T-cell receptors (TCRs) play a central role in the immune system. TCRs on T-cell surfaces can specifically recognize peptide antigens presented by antigen presenting cells (APCs)1. This recognition leads to the activation of T-cells and a series of functional outcomes (e.g. cytokine production, killing of the target cells). Understanding the functional role of TCRs is critical to harness the power of the immune system to treat a variety of immunology related diseases (e.g. cancer or autoimmunity).
It is convenient to study TCRs in mouse models, which can be accomplished in several ways. Making TCR transgenic mouse models is costly and time-consuming and currently there are only a limited number of them available2-4. Alternatively, mice with antigen-specific T-cells can be generated by bone marrow chimera. This method also takes several weeks and requires expertise5. Retroviral transduction of TCRs into in vitro activated mouse T-cells is a quick and relatively easy method to obtain T-cells of desired peptide-MHC specificity. Antigen-specific T-cells can be generated in one week and used in any downstream applications. Studying transduced T-cells also has direct application to human immunotherapy, as adoptive transfer of human T-cells transduced with antigen-specific TCRs is an emerging strategy for cancer treatment6.
Here we present a protocol to retrovirally transduce TCRs into in vitro activated mouse T-cells. Both human and mouse TCR genes can be used. Retroviruses carrying specific TCR genes are generated and used to infect mouse T-cells activated with anti-CD3 and anti-CD28 antibodies. After in vitro expansion, transduced T-cells are analyzed by flow cytometry.

We present a protocol to produce antigen-specific mouse T-cells using retroviral transduction

T-cell receptors (TCRs) play a central role in the immune system. TCRs on T-cell surfaces can specifically recognize peptide antigens presented by antigen ...

piggyBac Transposon System Modification of Primary Human T Cells

The piggyBac transposon system is naturally active, originally derived from the cabbage looper moth1,2. This non-viral system is plasmid based, most commonly utilizing two plasmids with one expressing the piggyBac transposase enzyme and a transposon plasmid harboring the gene(s) of interest between inverted repeat elements which are required for gene transfer activity. PiggyBac mediates gene transfer through a "cut and paste" mechanism whereby the transposase integrates the transposon segment into the genome of the target cell(s) of interest. PiggyBac has demonstrated efficient gene delivery activity in a wide variety of insect1,2, mammalian3-5, and human cells6 including primary human T cells7,8. Recently, a hyperactive piggyBac transposase was generated improving gene transfer efficiency9,10.
Human T lymphocytes are of clinical interest for adoptive immunotherapy of cancer11. Of note, the first clinical trial involving transposon modification of human T cells using the Sleeping beauty transposon system has been approved12. We have previously evaluated the utility of piggyBac as a non-viral methodology for genetic modification of human T cells. We found piggyBac to be efficient in genetic modification of human T cells with a reporter gene and a non-immunogenic inducible suicide gene7. Analysis of genomic integration sites revealed a lack of preference for integration into or near known proto-oncogenes13. We used piggyBac to gene-modify cytotoxic T lymphocytes to carry a chimeric antigen receptor directed against the tumor antigen HER2, and found that gene-modified T cells mediated targeted killing of HER2-positive tumor cells in vitro and in vivo in an orthotopic mouse model14. We have also used piggyBac to generate human T cells resistant to rapamycin, which should be useful in cancer therapies where rapamycin is utilized15.
Herein, we describe a method for using piggyBac to genetically modify primary human T cells. This includes isolation of peripheral blood mononuclear cells (PBMCs) from human blood followed by culture, gene modification, and activation of T cells. For the purpose of this report, T cells were modified with a reporter gene (eGFP) for analysis and quantification of gene expression by flow cytometry.
PiggyBac can be used to modify human T cells with a variety of genes of interest. Although we have used piggyBac to direct T cells to tumor antigens14, we have also used piggyBac to add an inducible safety switch in order to eliminate gene modified cells if needed7. The large cargo capacity of piggyBac has also enabled gene transfer of a large rapamycin resistant mTOR molecule (15 kb)15. Therefore, we present a non-viral methodology for stable gene-modification of primary human T cells for a wide variety of purposes.

piggyBac Transposon System Modification of Primary Human T Cells

We describe a method to genetically modify primary human T cells with a transgene using the non-viral piggyBac transposon system. T cells modified to using the piggyBac transposon system exhibit stable transgene expression.

The piggyBac transposon system is naturally active, originally derived from the cabbage looper moth1,2. This non-viral system is plasmid based, most ...

Highly Resolved Intravital Striped-illumination Microscopy of Germinal Centers

Monitoring cellular communication by intravital deep-tissue multi-photon microscopy is the key for understanding the fate of immune cells within thick tissue samples and organs in health and disease. By controlling the scanning pattern in multi-photon microscopy and applying appropriate numerical algorithms, we developed a striped-illumination approach, which enabled us to achieve 3-fold better axial resolution and improved signal-to-noise ratio, i.e. contrast, in more than 100 &#181;m tissue depth within highly scattering tissue of lymphoid organs as compared to standard multi-photon microscopy. The acquisition speed as well as photobleaching and photodamage effects were similar to standard photo-multiplier-based technique, whereas the imaging depth was slightly lower due to the use of field detectors. By using the striped-illumination approach, we are able to observe the dynamics of immune complex deposits on secondary follicular dendritic cells &#8211; on the level of a few protein molecules in germinal centers.

High-resolution intravital imaging with enhanced contrast up to 120 &#181;m depth in lymph nodes of adult mice is achieved by spatially modulating the excitation pattern of a multi-focal two-photon microscope. In 100 &#181;m depth we measured resolutions of 487 nm (lateral) and 551 nm (axial), thus circumventing scattering and diffraction limits.

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

Induction of Murine Intestinal Inflammation by Adoptive Transfer of Effector CD4+CD45RBhigh T Cells into Immunodeficient Mice

There are many different animal models available for studying the pathogenesis of human inflammatory bowel diseases (IBD), each with its own advantages and disadvantages. We describe here an experimental colitis model that is initiated by adoptive transfer of syngeneic splenic CD4+CD45RBhigh T cells into T and B cell deficient recipient mice. The CD4+CD45RBhigh T cell population that largely consists of na&#239;ve effector cells is capable of inducing chronic intestinal inflammation, closely resembling key aspects of human IBD. This method can be manipulated to study aspects of disease onset and progression. Additionally it can be used to study the function of innate, adaptive, and regulatory immune cell populations, and the role of environmental exposures, i.e., the microbiota, in intestinal inflammation. In this article we illustrate the methodology for inducing colitis with a step-by-step protocol. This includes a video demonstration of key technical aspects required to successfully develop this murine model of experimental colitis for research purposes.

Induction of Murine Intestinal Inflammation by Adoptive Transfer of Effector CD4+CD45RBhigh T Cells into Immunodeficient Mice

Here, we present a protocol to induce colonic inflammation in mice by adoptive transfer of syngeneic CD4+CD45RBhigh T cells into T and B cell deficient recipients. Clinical and histopathological features mimic human inflammatory bowel diseases. This method allows the study of the initiation of colonic inflammation and progression of disease.

There are many different animal models available for studying the pathogenesis of human inflammatory bowel diseases (IBD), each with its own advantages ...

T Cells Capture Bacteria by Transinfection from Dendritic Cells

Recently, we have shown, contrary to what is described, that CD4+ T cells, the paradigm of adaptive immune cells, capture bacteria from infected dendritic cells (DCs) by a process called transinfection. Here, we describe the analysis of the transinfection process, which occurs during the course of antigen presentation. This process was unveiled by using CD4+ T cells from transgenic OTII mice, which bear a T cell receptor (TCR) specific for a peptide of ovoalbumin (OVAp), which therefore can form stable immune complexes with infected dendritic cells loaded with this specific OVAp. The dynamics of green fluorescent protein (GFP)-expressing bacteria during DC-T cell transmission can be monitored by live-cell imaging and the quantification of bacterial transinfection can be performed by flow cytometry. In addition, transinfection can be quantified by a more sensitive method based in the use of gentamicin, a non-permeable aminoglycoside antibiotic killing extracellular bacteria but not intracellular ones. This classical method has been used previously in microbiology to study the efficiency of bacterial infections. We hereby explain the protocol of the complete process, from the isolation of the primary cells to the quantification of transinfection.

Here a protocol is presented to measure bacterial capture by CD4+ T cells which occurs during antigen presentation via transinfection from pre-infected dendritic cells (DC). We show how to perform the necessary steps: isolation of primary cells, infection of DC, DC/T cell conjugate formation, and measurement of bacterial T cell transfection.

Recently, we have shown, contrary to what is described, that CD4+ T cells, the paradigm of adaptive immune cells, capture bacteria from infected dendritic ...

The Use of Flow Cytometry to Assess the State of Chromatin in T Cells

During a proper immune response, quiescent T cells become activated upon antigen presentation to their antigen-specific T cell receptor. This leads to clonal proliferation of only those T cells that bear a receptor that recognizes the antigen. Chromatin decondensation is a hallmark of T cell activation and is required for T cells to acquire the ability to proliferate after antigen engagement. This change in chromatin condensation can be detected using antibodies raised against histone proteins. These antibodies cannot bind to their epitopes in na&#239;ve T cells as well as they can in activated T cells. We describe how to simultaneously stain T cell-specific surface markers, track viability with a fixable dead cell stain, and measure chromatin status via intracellular staining of Histone H3 proteins. Stained cells are analyzed by flow cytometry and chromatin condensation status is measured as the mean fluorescence intensity (MFI) of the Histone H3 stain. Chromatin decondensation during T cell activation is demonstrated as an increase in the MFI

Flow cytometry can be utilized to assess the state of chromatin within T cells. This protocol allows scientists to interpret evidence of chromatin decondensation during T cell activation demonstrated by an increase in the mean florescence intensity (MFI) of fluorescent Histone H3 antibodies

During a proper immune response, quiescent T cells become activated upon antigen presentation to their antigen-specific T cell receptor. This leads to ...

Preparation of CD4+ T Cells for Analysis of GD3 and GD2 Ganglioside Membrane Expression by Microscopy

The methods described herein for activation of na&#239;ve CD4+ T cells in suspension and their adherence in coverslips for confocal microscopy analysis allow the spatial localization and visualization of gangliosides involved in CD4+ T cell activation, that complement expression profiling experiments such as flow cytometry, western blotting or real-time PCR. The quantification of ganglioside expression through flow cytometry and their cellular localization through microscopy can be obtained by the use of anti-ganglioside antibodies with high affinity and specificity. Nonetheless, an adequate handling of cells in suspension involves the treatment of culture plates to promote the necessary adherence required for fluorescence or confocal microscopy acquisition. In this work, we describe a protocol for determining GD3 and GD2 ganglioside expression and colocalization with the TCR during na&#239;ve CD4+ T cell activation. Also, real-time PCR experiments using &#60;40,000 cells are described for the determination of the GD3 and GM2/GD2 synthase genes, demonstrating that gene analysis experiments can be performed with a low number of cells and without the need of additional low input RNA kits.

Preparation of CD4+ T Cells for Analysis of GD3 and GD2 Ganglioside Membrane Expression by Microscopy

We describe a standard antibody staining protocol for use in microscopy to determine the membrane expression and localization of gangliosides in resting and activated human na&#239;ve CD4+ T cells. Also described are real-time PCR experiments using &#60;40,000 cells that do not require additional low input RNA kits.

The methods described herein for activation of na&#239;ve CD4+ T cells in suspension and their adherence in coverslips for confocal microscopy analysis ...

Molecular Diffusion in Plasma Membranes of Primary Lymphocytes Measured by Fluorescence Correlation Spectroscopy

Fluorescence correlation spectroscopy (FCS) is a powerful technique for studying the diffusion of molecules within biological membranes with high spatial and temporal resolution. FCS can quantify the molecular concentration and diffusion coefficient of fluorescently labeled molecules in the cell membrane. This technique has the ability to explore the molecular diffusion characteristics of molecules in the plasma membrane of immune cells in steady state (i.e., without processes affecting the result during the actual measurement time). FCS is suitable for studying the diffusion of proteins that are expressed at levels typical for most endogenous proteins. Here, a straightforward and robust method to determine the diffusion rate of cell membrane proteins on primary lymphocytes is demonstrated. An effective way to perform measurements on antibody-stained live cells and commonly occurring observations after acquisition are described. The recent advancements in the development of photo-stable fluorescent dyes can be utilized by conjugating the antibodies of interest to appropriate dyes that do not bleach extensively during the measurements. Additionally, this allows for the detection of slowly diffusing entities, which is a common feature of proteins expressed in cell membranes. The analysis procedure to extract molecular concentration and diffusion parameters from the generated autocorrelation curves is highlighted. In summary, a basic protocol for FCS measurements is provided; it can be followed by immunologists with an understanding of confocal microscopy but with no other previous experience of techniques for measuring dynamic parameters, such as molecular diffusion rates.

A method to measure protein diffusion in membranes of primary immune cells using fluorescence correlation spectroscopy (FCS) is described. In this paper, the use of antibodies for fluorescent labeling is illustrated.

Fluorescence correlation spectroscopy (FCS) is a powerful technique for studying the diffusion of molecules within biological membranes with high spatial ...

Isolation and Flow Cytometric Analysis of Human Endocervical Gamma Delta T Cells

The female reproductive tract (FRT) mucosal immune system serves as the first line of defense. Better knowledge of the genital mucosa is therefore essential for understanding pathogenicity of different pathogens including HIV. Gamma delta (GD) T cells are the prototype of &#39;unconventional&#39; T cells and represent a relatively small subset of T cells defined by their expression of heterodimeric T-cell receptors (TCRs) composed of gamma and delta chains. This sets them apart from the classical and much better known CD4+ helper T cells and CD8+ cytotoxic T cells that are defined by alpha-beta TCRs. GD T cells often show tissue-specific localization and are enriched in epithelium. GD T cells orchestrate immune responses in inflammation, tumor surveillance, infectious disease, and autoimmunity.
Here, we present a method to reproducibly isolate and analyze human endocervical intraepithelial GD T lymphocytes. We have used endocervical cytobrush samples from women participating in the Women&#39;s Interagency HIV Infection Study (WIHS). Knowledge about GD T cells interactions during conditions in which there is an insult to the vaginal mucosal could be applied to any clinical study in which mucosal vulnerability is addressed, including the development of vaginal microbicides.In addition, knowledge about mucosal GD T cell responses has potential for application of GD T cell-based immune therapy in treating infectious diseases.

We describe here an isolation method to obtain human endocervical intraepithelial lymphocytes for the analysis of intraepithelial gamma delta T cells. This protocol can be extended for the purification of endocervical gamma delta T cells by magnetic beads or by cell sorting.

The female reproductive tract (FRT) mucosal immune system serves as the first line of defense. Better knowledge of the genital mucosa is therefore ...

Induction of Paralysis and Visual System Injury in Mice by T Cells Specific for Neuromyelitis Optica Autoantigen Aquaporin-4

While it is recognized that aquaporin-4 (AQP4)-specific T cells and antibodies participate in the pathogenesis of neuromyelitis optica (NMO), a human central nervous system (CNS) autoimmune demyelinating disease, creation of an AQP4-targeted model with both clinical and histologic manifestations of CNS autoimmunity has proven challenging. Immunization of wild-type (WT) mice with AQP4 peptides elicited T cell proliferation, although those T cells could not transfer disease to na&#239;ve recipient mice. Recently, two novel AQP4 T cell epitopes, peptide (p) 135-153 and p201-220, were identified when studying immune responses to AQP4 in AQP4-deficient (AQP4-/-) mice, suggesting T cell reactivity to these epitopes is normally controlled by thymic negative selection. AQP4-/- Th17 polarized T cells primed to either p135-153 or p201-220 induced paralysis in recipient WT mice, that was associated with predominantly leptomeningeal inflammation of the spinal cord and optic nerves. Inflammation surrounding optic nerves and involvement of the inner retinal layers (IRL) were manifested by changes in serial optical coherence tomography (OCT). Here, we illustrate the approaches used to create this new in vivo model of AQP4-targeted CNS autoimmunity (ATCA), which can now be employed to study mechanisms that permit development of pathogenic AQP4-specific T cells and how they may cooperate with B cells in NMO pathogenesis.

Here, we present a protocol to induce paralysis and opticospinal inflammation by transfer of aquaporin-4 (AQP4)-specific T cells from AQP4-/- mice into WT mice. In addition, we demonstrate how to use serial optical coherence tomography to monitor visual system dysfunction.

While it is recognized that aquaporin-4 (AQP4)-specific T cells and antibodies participate in the pathogenesis of neuromyelitis optica (NMO), a human ...