Name: imaging cd4 t cell interstitial migration in the inflamed dermis
Uploaded: 2016-03-25T14:00:00
Description: Watch this Scientific Journal Video about Imaging CD4 T Cell Interstitial Migration in the Inflamed Dermis at JoVE.com

The authors thank the University of Rochester Multiphoton Microscope Core facility for help with live imaging. Supported by NIH AI072690 and AI02851 to DJF; AI114036 to AG and AI089079 to MGO.

All procedures involving mice were approved by the Institutional Animal Care and Use Committee of the University of Rochester, and carried out in strict accordance with the Animal Welfare Act and the Public Health Service Policy on Humane Care and Use of Laboratory Animals administered by the National Institutes of Health, Office of Laboratory Animal Welfare.
1. Preparation of Effector CD4 T Cells
NOTE: BALB/c TCR-transgenic DO11.10 mice that specifically recognize a ...

Significance
Here we present a complete protocol for the 4D visualization of transferred, antigen-specific effector Th1 cells in the intact mouse ear dermis. This method provides advantages over some current imaging modalities for several reasons. By imaging the ventral ear dermis, we are able to forego hair removal that is required for imaging protocols involving other skin sites. Although depilatories are generally mild, they have been shown to cause disruption to the skin barrier <...

The effector function of CD4 T cells is critically dependent on their ability to rapidly enter and traverse a wide variety of peripheral tissues to survey for damage, locate foci of infection, or cause pathology from chronic infection or autoimmunity. While the processes of homing to inflamed sites1-4 and extravasation5-7 from the vasculature into tissues have been well-characterized, the factors that drive and regulate the interstitial motility of T cells remain undefined. The migration of T cells in complex 3D environments has been studied in vitro through the use of artificial matrices8-10 or microfluidic devices11,12, but these fail to recapitulate the complex and dynamic environment of an in vivo system. It is only recently, with the advent of high-resolution multi-color intravital imaging that it has become possible to study the dynamic behavior of immune cells in situ, allowing for a better understanding of intact immune responses.
Over a decade ago, several influential studies were published that first utilized multiphoton microscopy to address immunological questions. Early studies focused on the behavior of immune cells within explanted lymphoid organs13-16, which were soon followed by techniques to image exposed lymph nodes in anesthetized mice17. Imaging allowed for new fundamental observations about the stages of lymph node priming of T cells18, the mechanisms by which T cells migrate in secondary lymphoid organs19, T cell interactions with other immune cells20,21, and dynamic T cell positioning within the lymph node22. Although many early studies focused on lymph node dynamics, intravital imaging has been since been utilized to image the immune response in many peripheral tissues, including the brain23-25, liver26, lung27, and skin28-30. 
The mouse ear dermis is particularly well poised for imaging, due to the thinness of ear skin, a relative lack of hair, and the ease with which it can be isolated from respiratory movements31. Indeed, the ear dermis has been used to image the interstitial behavior of dendritic cells32,33, T cells28,29,34,35, and neutrophils36,37, and is a well-established site for studying dermal inflammation. Increasingly, non-invasive procedures have been replacing surgical preparations of the skin, including split dermis38,39, flank39,40, or dorsal skin flap window39,41 models, that can induce changes to the local inflammatory milieu. The use of transferred, in vitro-primed, antigen-specific CD4 effector T cells allows for the study of a homogenous population of cells in the context of a dermal inflammatory response30. Here we describe a non-invasive imaging procedure that allows for the visualization of antigen-specific effector CD4 T cells in the dermal interstitium of the inflamed mouse ear, and the ability to manipulate these cells in real-time by introducing blocking antibodies through a venous catheter. We show that this model is effective for tracking the movement of CD4 T cells in the dermis and for querying the mechanisms that govern this motility.

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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">BALB/c mice</td>
			<td style="width:145px;">Jackson Laboratories</td>
			<td style="width:196px;">000651</td>
			<td style="width:472px;">Mice used were bred in-house</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">DO11.10 mice</td>
			<td>Jackson Laboratories</td>
			<td>003303</td>
			<td>Mice used were bred in-house</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">HBSS</td>
			<td>Fisher</td>
			<td>10-013-CV</td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Newborn Calf Serum (NCS)</td>
			<td>Thermo/HyClone</td>
			<td>SH30118.03</td>
			<td>Heat inactivated at 56 &#176;C for 30 minutes</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Guinea Pig Complement</td>
			<td>Cedarlane</td>
			<td>CL-5000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">anti-CD8 antibody</td>
			<td>ATCC</td>
			<td>3.155 (ATCC TIB-211)</td>
			<td>Antibodies derived from&#160; this hybridoma</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">anti-MHC Class II antibody</td>
			<td>ATCC</td>
			<td>M5/114.15.2 (ATCC TIB-120)</td>
			<td>Antibodies derived from&#160; this hybridoma</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">anti-CD24 antibody</td>
			<td>ATCC</td>
			<td>J11d.2 (ATCC TIB-183)</td>
			<td>Antibodies derived from&#160; this hybridoma</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">anti-Thy1.2 antibody</td>
			<td>ATCC</td>
			<td>J1j.10 (ATCC TIB-184)</td>
			<td>Antibodies derived from&#160; this hybridoma</td>
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		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Ficoll (Fico/Lite-LM)</td>
			<td>Atlanta Biologicals</td>
			<td>I40650</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">PBS</td>
			<td>Fisher</td>
			<td>21-040-CV</td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">EDTA</td>
			<td>Fisher</td>
			<td>15323591</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:247px;">biotinylated anti-CD62L antibody (clone MEL-14)</td>
			<td>BD</td>
			<td>553149</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:247px;">streptavidin magnetic separation beads</td>
			<td>Miltenyi</td>
			<td>130-048-101</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">MACS LS Separation Column</td>
			<td>Miltenyi</td>
			<td>130-042-401</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">recombinant human IL-2</td>
			<td>Peprotech</td>
			<td>200-02</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">recombinant mouse IL-4</td>
			<td>Peprotech</td>
			<td>214-14</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">recombinant mouse IL-12</td>
			<td>Peprotech</td>
			<td>210-12</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">anti-IFNg antibody (clone XMG 1.2)</td>
			<td>eBioscience</td>
			<td>16-7311-85</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">anti-IL-4 antibody (clone 11b11)</td>
			<td>eBioscience</td>
			<td>16-7041-85</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">RPMI</td>
			<td>VWR</td>
			<td>45000-412</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Penicillin/Streptomycin</td>
			<td>Fisher</td>
			<td>15303641</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">L-glutamine</td>
			<td>Fisher</td>
			<td>15323671</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">2-mercaptoethanol</td>
			<td>Bio-Rad</td>
			<td>161-0710</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">ovalbumin peptide</td>
			<td>Biopeptide</td>
			<td></td>
			<td>ISQAVHAAHAEINEAGR-OH peptide</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Fetal Calf Serum (FCS)</td>
			<td>Thermo/HyClone</td>
			<td>SV30014.03</td>
			<td>Heat inactivated at 56 &#176;C for 30 minutes</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">24-well culture plate</td>
			<td>LPS</td>
			<td>3526</td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">CFSE</td>
			<td>Life Technologies</td>
			<td>C34554</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">CMTMR</td>
			<td>Life Technologies</td>
			<td>C2927</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">28 G1/2 insulin syringes, 1ml</td>
			<td>BD</td>
			<td>329420</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">28 G1/2 insulin syringes, 300&#956;l</td>
			<td>BD</td>
			<td>309301</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">27 G1/2 TB syringes, 1ml</td>
			<td>BD</td>
			<td>309623</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">30 G1/2 needles</td>
			<td>BD</td>
			<td>305106</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">PE-10 medical tubing</td>
			<td>BD</td>
			<td>427400</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:247px;">cyanoacrylate veterinary adhesive (Vetbond)</td>
			<td>3M</td>
			<td>1469SB</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">heating plate</td>
			<td>WPI</td>
			<td>61830</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Heating plate controller</td>
			<td>WPI</td>
			<td>ATC-2000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Water blanket controller</td>
			<td>Gaymar</td>
			<td>TP500</td>
			<td>No longer in production, newer equivalent available</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">water blanket</td>
			<td>Kent Scientific</td>
			<td>TP3E</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Isoflurane vaporizer</td>
			<td>LEI Medical</td>
			<td>Isotec 4</td>
			<td>No longer in production, newer equivalent available</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">isoflurane</td>
			<td>Henry Schein</td>
			<td></td>
			<td>Ordered through Veterinary staff</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">microcentrifuge tubes</td>
			<td>VWR</td>
			<td>20170-038</td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">medical tape</td>
			<td>3M</td>
			<td>1538-0</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">isoflurane nosecone</td>
			<td></td>
			<td></td>
			<td>Built In-house, see Fig 2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">imaging platform</td>
			<td></td>
			<td></td>
			<td>Built In-house, see Fig 2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">curved forceps</td>
			<td>WPI</td>
			<td>15915-G</td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">scissors</td>
			<td>Roboz</td>
			<td>RS-6802</td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">glass coverslips</td>
			<td>VWR</td>
			<td></td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">high vacuum grease</td>
			<td>Fisher</td>
			<td>146355D</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">cotton swabs</td>
			<td></td>
			<td></td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">delicate task wipes</td>
			<td>Fisher</td>
			<td>34155</td>
			<td>Multiple Equivalent</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:247px;">Olympus Fluoview 1000 AOM-MPM upright microscope with Spectra-Physics MaiTai HP DeepSee Ti:Sa laser</td>
			<td>Olympus</td>
			<td></td>
			<td>call for quote</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">optical table with vibration control</td>
			<td>Newport</td>
			<td></td>
			<td>call for quote</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:247px;">25x NA 1.05 water immersion objective for multiphoton imaging</td>
			<td>Olympus</td>
			<td>XLPLN25XWMP2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">objective heater</td>
			<td>Bioptechs</td>
			<td>PN 150815</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Detection filter cube</td>
			<td>Olympus</td>
			<td>FV10-MRVGR/XR</td>
			<td>Proprietary cube, can be approximated from individual filters/dichroics</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:247px;">anti-integrin &#946;1 antibody (clone hMb1-1)</td>
			<td>eBioscience</td>
			<td>16-0291-85</td>
			<td>Azide free, low endotoxin</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:247px;">anti-integrin &#946;3 antibody (clone 2C9.G3)</td>
			<td>eBioscience</td>
			<td>16-0611-82</td>
			<td>Azide free, low endotoxin</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Texas Red Dextran (70,000 MW)</td>
			<td>Life Technologies</td>
			<td>D-1830</td>
			<td></td>
		</tr>
	</tbody>
</table>

imaging cd4 t cell interstitial migration in the inflamed dermis

The ability of CD4 T cells to carry out effector functions is dependent upon the rapid and efficient migration of these cells in inflamed peripheral tissues through an as-yet undefined mechanism. The application of multiphoton microscopy to the study of the immune system provides a tool to measure the dynamics of immune responses within intact tissues. Here we present a protocol for non-invasive intravital multiphoton imaging of CD4 T cells in the inflamed mouse ear dermis. Use of a custom imaging platform and a venous catheter allows for the visualization of CD4 T cell dynamics in the dermal interstitium, with the ability to interrogate these cells in real-time via the addition of blocking antibodies to key molecular components involved in motility. This system provides advantages over both in vitro models and surgically invasive imaging procedures. Understanding the pathways used by CD4 T cells for motility may ultimately provide insight into the basic function of CD4 T cells as well as the pathogenesis of both autoimmune diseases and pathology from chronic infections.

The ability to study immune responses in situ without altering the immune environment is essential in studying real-time interactions of T effector cells with an inflamed tissue. Imaging of the intact ear dermis by this protocol, outlined in Figure 1A and B, allows for the visualization of transferred fluorescently labeled T effector cells in the dermal interstitium. This permits both high-resolution (Figure 1C) and time-lapse (<...

Watch this Scientific Journal Video about Imaging CD4 T Cell Interstitial Migration in the Inflamed Dermis at JoVE.com

Imaging CD4 T Cell Interstitial Migration in the Inflamed Dermis

The mechanisms that govern the interstitial motility of CD4 effector T cells at sites of inflammation are relatively unknown. We present a non-invasive approach to visualize and manipulate in vitro-primed CD4 T cells in the inflamed ear dermis, allowing for study of the dynamic behavior of these cells in situ.

The ability of CD4 T cells to carry out effector functions is dependent upon the rapid and efficient migration of these cells in inflamed peripheral ...

The overall goal of this imaging protocol is to visualize CD4 positive T Cell dynamics in the inflamed skin. This method can help answer key questions in the field of immunology, such as, what are the mechanisms that underlie immune cell motility, and function in inflamed tissues. The main advantage of this technique, is that it provides a minimally invasive way to study CD4 T cell dynamic behavior In Situ.Visual demonstration of this method is critical, as the steps to prepare the ear for imaging are difficult to learn, and proper positioning of the ear is necessary to capture high quality images. I'm Alison Gaylo, a graduate student, and I will be doing the demonstration of this protocol. Begin by aspirating 300 microliters of fluorescently labeled effector T cell suspension per mouse into a syringe equipped with a 27 and a half gauge needle.Then turn the syringe needle side up, and gently flick the shaft of the syringe, moving the plunger up and down as necessary to remove any bubbles. When the cells are ready, transfer the mice into a clean cage, and place them under a heat lamp, until the tail veins are vasodilated. Then transfer the first mouse into the restrainer, and wipe the tail with an alcohol swab.After identifying a lateral tail vein, slowly inject 200 microliters of cells into the vein. When all of the cells have been transferred, draw 50 microliters of complete fluorescens emulsion into a 28 and a half gauge insulin syringe and press down firmly on the plunger to remove any large air bubbles. Then place a thimble on the left index finger, and carefully grasp the mouse's ear between the left thumb and thimble, with the ventral ear facing up.Then slide the needle, bevel side up, into the dermis in the outer third of the pinna, and slightly off center, and slowly inject ten microliters of emulsion into the tissue. After injecting all of the animals, monitor the mice until they are fully recovered. Three days following the immunization, vasodilate the tail veins of the injected animals as just demonstrated.After anesthetizing, immobilize the tail of the first mouse with a pair of forceps. Wipe the tail with an alcohol swab, then carefully slide a 30 and a half gauge needle catheter into a lateral tail vein, checking for patency by gentle pressure to the syringe plunger. When the catheter is in place, apply one to two drops of cyanoacrylate tissue adhesive to the injection site, and allow the adhesive to dry for approximately 30 seconds.Then use scissors to carefully trim the whiskers and the hair from the back and sides of the ear. Next, use a cotton swab to moisten the inner surface of the ear with PBS. Then rotate the mouse, and flatten the injected ear onto a 24 by 50 millimeter number one point five glass cover slip, until it is flush with the glass.Blot away the excess PBS. Then use two pairs of curved forceps to grasp an approximately 20 millimeter long piece of fabric tape lengthwise at the top corners, and place the bottom of the tape onto the cover slip at the top of the mouse's ear. Roll the tape over the rest of the ear, pushing the excess hair out of the way with the forceps as necessary, and use a dry cotton swab to gently press the tape around the ear to ensure a tight seal, taking care not to press on the ear itself.It is essential that the ear is taped properly to the cover slip with a good seal on both sides and with minimal air bubbles, as this will affect the quality of the images that can be obtained. Now tape a fluorescent microscope imaging platform to a 37 degree Celsius heating block, and apply vacuum grease to both sides of the ear area of the platform. Rotate the mouse to place the cover slip onto the platform, taking care to align the ear in the center of the felt.When the ear is in place, snap the isoflurane nose cone into the holder on the platform, ensuring that the cone is secure, and completely covering the mouse's nose. Then use a cotton swab to firmly, but carefully, press the cover slip onto the imaging platform, spreading the vacuum grease under the cover slip. Wrap two 20 millimeter pieces and two longer pieces of tape around the upper portion of the platform to affix the cover slip to the platform.Next, move the mouse to the microscope stage. Secure the platform with more tape, and pipe a double layer of vacuum grease onto the cover slip around the ear. Then wrap a water filled heating blanket around the mouse, and fill the vacuum grease reservoir with 37 degrees Celsius distilled water.For In Vivo time lapse imaging, begin by positioning the objective over the center of the ear, and lower the objective until it just contacts the surface of the water in the reservoir. Next, using an external light source, slowly lower the objective until the surface of the ear comes into focus. Then, lower the inner and outer curtains around the microscope stage, and adjust the laser wave length to 900 nanometers in the MP laser controller window, the laser power in the acquisition setting laser window, and the PMT voltages in the image acquisition control window.In the acquisition setting size and mode windows, set the microscope to five twelve by five twelve pixel resolution, with a two microsecond per pixel dwell time, and select XY repeat to activate a live imaging mode for scanning through the tissue. Once an appropriate imaging field has been located, locate the highest cell in the dermis, and click the set zero button to set the Z position to zero. Scroll down in the Z direction to measure the extent of the cell depth.Then set the starting and end positions in the acquisition setting microscope window, and adjust the instrument PMT voltages and laser power in the bright Z window to optimize the visualization of the cells throughout the depth of the imaging field. Check the depth and time buttons, and set a common filter to scan the image three times per line in the image acquisition control filter mode window. Adjust the Z slice depth in the image acquisition microscope window so that it takes approximately one minute to capture a complete stack as noted in the time view window.Then, to assess the stability of the tissue, set the number of repeats to five in the acquisition setting time scan window, and click the scan button to capture a five minute time lapse image of the area. If the tissue is stable after five minutes, set the number of repeats to between 30 and 45 in the acquisition setting time scan window, and collect a 30 to 45 minute time lapse image, monitoring for any minor tissue drift as the image is collected. Save the pre-antibody image in the appropriate format, and then draw the antibody mixture into a one milliliter tuberculin syringe, taking care to remove all of the air bubbles.Gently press the plunger so that the antibody solution forms a droplet at the end of the needle, and lift the curtains around the stage to locate the catheter. Replace the PBS syringe with the syringe of antibody, and then slowly inject the antibodies into the catheter. When the antibodies have been successfully injected, re-lower the curtains and note the time of injection.Then immediately start collecting a new 20 to 40 minute imaging sequence, in the same location, using the same instrument settings as the pre-antibody image. Finally, save the post-antibody image file in the appropriate format, and carefully remove the mouse from the microscope stage, monitoring the animal until it is fully recovered. Imaging of the intact ear dermis by this protocol facilitates the acquisition of high resolution and time lapse images of effector T cell dynamics in the inflamed dermis.In this movie, the green adoptively transferred effector T cells can be observed moving throughout the dermal tissue. After the administration of antibeta one and antibeta three entogrin blocking antibodies through the catheter, however, the previously motile cells arrest within the dermis. The cells exhibit a decreased average velocity after antibody administration as well as a significant decrease in their meandering index.That is, the ration of the total displacement to the total track length. Autofluorescents from hair follicles, shadowing and autofluorescents from overlying hair, and air bubbles trapped between the ear surface and the cover slip, can all lead to imaging artifacts, which obscure the visualization of the T cells, and interfere with the automated image analysis software. In addition, using multiple sources of heat can cause tissue stability issues, leading to large oscillations during imaging that make interpreting the results difficult.Once mastered, imaging the CD4 T cells in the dermis can be completed in two to three hours, if the procedure has been performed correctly. While attempting this procedure, it's important to remember to follow the appropriate animal care and use guidelines for working with mice. This procedure can be adapted to visualize other T cell subsets or types of immune cells in the ear, using different models of infect, or different methods of inducing inflammation.After its development, intravital imaging paved the way for researchers in the field of immunology, to explore the dynamics of ongoing immune responses in living animals. Don't forget that working with a multi-phosphor laser can be extremely hazardous and that precautions, such as proper shielding, should always be taken while performing this procedure. After watching this video, you should have a good understanding of how to induce inflammation in a mouse ear dermis, how to use intravital imaging to capture the time lapse images of CD4 T cell activity before and after antibody administration.

imaging-cd4-t-cell-interstitial-migration-in-the-inflamed-dermis

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 ...

Competitive Homing Assays to Study Gut-tropic T Cell Migration

In order to exert their function lymphocytes need to leave the blood and migrate into different tissues in the body. Lymphocyte adhesion to endothelial cells and tissue extravasation is a multistep process controlled by different adhesion molecules (homing receptors) expressed on lymphocytes and their respective ligands (addressins) displayed on endothelial cells 1 2. Even though the function of these adhesion receptors can be partially studied ex vivo, the ultimate test for their physiological relevance is to assess their role during in vivo lymphocyte adhesion and migration. Two complementary strategies have been used for this purpose: intravital microscopy (IVM) and homing experiments. Although IVM has been essential to define the precise contribution of specific adhesion receptors during the adhesion cascade in real time and in different tissues, IVM is time consuming and labor intensive, it often requires the development of sophisticated surgical techniques, it needs prior isolation of homogeneous cell populations and it permits the analysis of only one tissue/organ at any given time. By contrast, competitive homing experiments allow the direct and simultaneous comparison in the migration of two (or even more) cell subsets in the same mouse and they also permit the analysis of many tissues and of a high number of cells in the same experiment.
Here we describe the classical competitive homing protocol used to determine the advantage/disadvantage of a given cell type to home to specific tissues as compared to a control cell population. We chose to illustrate the migratory properties of gut-tropic versus non gut-tropic T cells, because the intestinal mucosa is the largest body surface in contact with the external environment and it is also the extra-lymphoid tissue with the best-defined migratory requirements. Moreover, recent work has determined that the vitamin A metabolite all-trans retinoic acid (RA) is the main molecular mechanism responsible for inducing gut-specific adhesion receptors (integrin a4b7and chemokine receptor CCR9) on lymphocytes. Thus, we can readily generate large numbers of gut-tropic and non gut-tropic lymphocytes ex vivoby activating T cells in the presence or absence of RA, respectively, which can be finally used in the competitive homing experiments described here.

Competitive homing experiments allow to directly assessing the migratory properties of two different cell populations in a single mouse. Here we illustrate this procedure by comparing the migration of ex vivo-generated gut-tropic versus non-gut tropic T cells.

In order to exert their function lymphocytes need to leave the blood and migrate into different tissues in the body. Lymphocyte adhesion to endothelial ...

A Quantitative Evaluation of Cell Migration by the Phagokinetic Track Motility Assay

Cellular motility is an important biological process for both unicellular and multicellular organisms. It is essential for movement of unicellular organisms towards a source of nutrients or away from unsuitable conditions, as well as in multicellular organisms for tissue development, immune surveillance and wound healing, just to mention a few roles1,2,3. Deregulation of this process can lead to serious neurological, cardiovascular and immunological diseases, as well as exacerbated tumor formation and spread4,5. Molecularly, actin polymerization and receptor recycling have been shown to play important roles in creating cellular extensions (lamellipodia), that drive the forward movement of the cell6,7,8. However, many biological questions about cell migration remain unanswered.
The central role for cellular motility in human health and disease underlines the importance of understanding the specific mechanisms involved in this process and makes accurate methods for evaluating cell motility particularly important. Microscopes are usually used to visualize the movement of cells. However, cells move rather slowly, making the quantitative measurement of cell migration a resource-consuming process requiring expensive cameras and software to create quantitative time-lapsed movies of motile cells. Therefore, the ability to perform a quantitative measurement of cell migration that is cost-effective, non-laborious, and that utilizes common laboratory equipment is a great need for many researchers.
The phagokinetic track motility assay utilizes the ability of a moving cell to clear gold particles from its path to create a measurable track on a colloidal gold-coated glass coverslip9,10. With the use of freely available software, multiple tracks can be evaluated for each treatment to accomplish statistical requirements. The assay can be utilized to assess motility of many cell types, such as cancer cells11,12, fibroblasts9, neutrophils13, skeletal muscle cells14, keratinocytes15, trophoblasts16, endothelial cells17, and monocytes10,18-22. The protocol involves the creation of slides coated with gold nanoparticles (Au&deg;) that are generated by a reduction of chloroauric acid (Au3+) by sodium citrate. This method was developed by Turkevich et al. in 195123 and then improved in the 1970s by Frens et al.24,25. As a result of this chemical reduction step, gold particles (10-20 nm in diameter) precipitate from the reaction mixture and can be applied to glass coverslips, which are then ready for use in cellular migration analyses9,26,27.
In general, the phagokinetic track motility assay is a quick, quantitative and easy measure of cellular motility. In addition, it can be utilized as a simple high-throughput assay, for use with cell types that are not amenable to time-lapsed imaging, as well as other uses depending on the needs of the researcher. Together, the ability to quantitatively measure cellular motility of multiple cell types without the need for expensive microscopes and software, along with the use of common laboratory equipment and chemicals, make the phagokinetic track motility assay a solid choice for scientists with an interest in understanding cellular motility.

The phagokinetic motility track assay is a method used to assess the movement of cells. Specifically, the assay measures chemokinesis (random cell motility) over time in a quantitative manner. The assay takes advantage of the ability of cells to create a measurable track of their movement on colloidal gold-coated coverslips.

Cellular motility is an important biological process for both unicellular and multicellular organisms. It is essential for movement of unicellular ...

Real-time Live Imaging of T-cell Signaling Complex Formation

Protection against infectious diseases is mediated by the immune system 1,2. T lymphocytes are the master coordinators of the immune system, regulating the activation and responses of multiple immune cells 3,4. T-cell activation is dependent on the recognition of specific antigens displayed by antigen presenting cells (APCs). The T-cell antigen receptor (TCR) is specific to each T-cell clone and determines antigen specificity 5. The binding of the TCR to the antigen induces the phosphorylation of components of the TCR complex. In order to promote T-cell activation, this signal must be transduced from the membrane to the cytoplasm and the nucleus, initiating various crucial responses such as recruitment of signaling proteins to the TCR;APC site (the immune synapse), their molecular activation, cytoskeletal rearrangement, elevation of intracellular calcium concentration, and changes in gene expression 6,7. The correct initiation and termination of activating signals is crucial for appropriate T-cell responses. The activity of signaling proteins is dependent on the formation and termination of protein-protein interactions, post translational modifications such as protein phosphorylation, formation of protein complexes, protein ubiquitylation and the recruitment of proteins to various cellular sites 8. Understanding the inner workings of the T-cell activation process is crucial for both immunological research and clinical applications.
Various assays have been developed in order to investigate protein-protein interactions; however, biochemical assays, such as the widely used co-immunoprecipitation method, do not allow protein location to be discerned, thus precluding the observation of valuable insights into the dynamics of cellular mechanisms. Additionally, these bulk assays usually combine proteins from many different cells that might be at different stages of the investigated cellular process. This can have a detrimental effect on temporal resolution. The use of real-time imaging of live cells allows both the spatial tracking of proteins and the ability to temporally distinguish between signaling events, thus shedding light on the dynamics of the process 9,10. We present a method of real-time imaging of signaling-complex formation during T-cell activation. Primary T-cells or T-cell lines, such as Jurkat, are transfected with plasmids encoding for proteins of interest fused to monomeric fluorescent proteins, preventing non-physiological oligomerization 11. Live T cells are dropped over a coverslip pre-coated with T-cell activating antibody 8,9, which binds to the CD3/TCR complex, inducing T-cell activation while overcoming the need for specific activating antigens. Activated cells are constantly imaged with the use of confocal microscopy. Imaging data are analyzed to yield quantitative results, such as the colocalization coefficient of the signaling proteins.

We describe a live-cell imaging method that provides insight into protein dynamics during the T-cell activation process. We demonstrate the combined usage of the T-cell spreading assay, confocal microscopy and imaging analysis to yield quantitative results to follow signaling complex formation throughout T-cell activation.

Protection against infectious diseases is mediated by the immune system 1,2. T lymphocytes are the master coordinators of the immune system, regulating ...

Monitoring Dendritic Cell Migration using 19F / 1H Magnetic Resonance Imaging

Continuous advancements in noninvasive imaging modalities such as magnetic resonance imaging (MRI) have greatly improved our ability to study physiological or pathological processes in living organisms. MRI is also proving to be a valuable tool for capturing transplanted cells in vivo. Initial cell labeling strategies for MRI made use of contrast agents that influence the MR relaxation times (T1, T2, T2*) and lead to an enhancement (T1) or depletion (T2*) of signal where labeled cells are present. T2* enhancement agents such as ultrasmall iron oxide agents (USPIO) have been employed to study cell migration and some have also been approved by the FDA for clinical application. A drawback of T2* agents is the difficulty to distinguish the signal extinction created by the labeled cells from other artifacts such as blood clots, micro bleeds or air bubbles. In this article, we describe an emerging technique for tracking cells in vivo that is based on labeling the cells with fluorine (19F)-rich particles. These particles are prepared by emulsifying perfluorocarbon (PFC) compounds and then used to label cells, which subsequently can be imaged by 19F MRI. Important advantages of PFCs for cell tracking in vivo include (i) the absence of carbon-bound 19F in vivo, which then yields background-free images and complete cell selectivityand(ii) the possibility to quantify the cell signal by 19F MR spectroscopy.

Monitoring Dendritic Cell Migration using 19F / 1H Magnetic Resonance Imaging

Tracking of cells using MRI has gained remarkable attention in the past years. This protocol describes the labeling of dendritic cells with fluorine (19F)-rich particles, the in vivo application of these cells, and monitoring the extent of their migration to the draining lymph node with 19F/1H MRI and 19F MRS.

Continuous  advancements in noninvasive imaging modalities such as magnetic resonance  imaging (MRI) have greatly improved our ability to study ...

Isolation and Th17 Differentiation of Na&iuml;ve CD4 T Lymphocytes

Th17 cells are a distinct subset of T cells that have been found to produce interleukin 17 (IL-17), and differ in function from the other T cell subsets including Th1, Th2, and regulatory T cells. Th17 cells have emerged as a central culprit in overzealous inflammatory immune responses associated with many autoimmune disorders. In this method we purify T lymphocytes from the spleen and lymph nodes of C57BL/6 mice, and stimulate purified CD4+ T cells under control and Th17-inducing environments. The Th17-inducing environment includes stimulation in the presence of anti-CD3 and anti-CD28 antibodies, IL-6, and TGF-&#946;. After incubation for at least 72 hours and for up to five days at 37 &#176;C, cells are subsequently analyzed for the capability to produce IL-17 through flow cytometry, qPCR, and ELISAs. Th17 differentiated CD4+CD25- T cells can be utilized to further elucidate the role that Th17 cells play in the onset and progression of autoimmunity and host defense. Moreover, Th17 differentiation of CD4+CD25- lymphocytes from distinct murine knockout/disease models can contribute to our understanding of cell fate plasticity.

Isolation and Th17 Differentiation of Na&amp;#239;ve CD4 T Lymphocytes

With effector functions distinct from other T cell subsets, Th17 cells have been centrally implicated in inflammatory autoimmunity. This in vitro Th17 differentiation protocol provides a means to determine whether na&#239;ve CD4+ T lymphocytes can differentiate into Th17 cells, and to further examine their role in autoimmunity and host response.

Th17 cells are a distinct subset of T cells that have been found to produce interleukin 17 (IL-17), and differ in function from the other T cell subsets ...

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function

T cell exhaustion is a major factor in failed pathogen clearance during chronic viral infections. Immunoregulatory pathways, such as PD-1 and IL-10, are upregulated upon this ongoing antigen exposure and contribute to loss of proliferation, reduced cytolytic function, and impaired cytokine production by CD4 and CD8 T cells. In the murine model of LCMV infection, administration of blocking antibodies against these two pathways augmented T cell responses. However, there is currently no in vitro assay to measure the impact of such blockade on cytokine secretion in cells from human samples. Our protocol and experimental approach enable us to accurately and efficiently quantify the restoration of cytokine production by HIV-specific CD4 T cells from HIV infected subjects.
Here, we depict an in vitro experimental design that enables measurements of cytokine secretion by HIV-specific CD4 T cells and their impact on other cell subsets. CD8 T cells were depleted from whole blood and remaining PBMCs were isolated via Ficoll separation method. CD8-depleted PBMCs were then incubated with blocking antibodies against PD-L1 and/or IL-10R&#945; and, after stimulation with an HIV-1 Gag peptide pool, cells were incubated at 37 &#176;C, 5% CO2. After 48 hr, supernatant was collected for cytokine analysis by beads arrays and cell pellets were collected for either phenotypic analysis using flow cytometry or transcriptional analysis using qRT-PCR. For more detailed analysis, different cell populations were obtained by selective subset depletion from PBMCs or by sorting using flow cytometry before being assessed in the same assays. These methods provide a highly sensitive and specific approach to determine the modulation of cytokine production by antigen-specific T-helper cells and to determine functional interactions between different populations of immune cells.

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function

We developed an in vitro assay to investigate the role of immunoregulatory pathways in the regulation of cytokine secretion by HIV-specific CD4 T cells.

T cell exhaustion is a major factor in failed pathogen clearance during chronic viral infections. Immunoregulatory pathways, such as PD-1 and IL-10, are ...

Transplantation of Tail Skin to Study Allogeneic CD4 T Cell Responses in Mice

The study of T cell responses and their consequences during allo-antigen recognition requires a model that enables one to distinguish between donor and host T cells, to easily monitor the graft, and to adapt the system in order to answer different immunological questions. Medawar and colleagues established allogeneic tail-skin transplantation in mice in 1955. Since then, the skin transplantation model has been continuously modified and adapted to answer specific questions. The use of tail-skin renders this model easy to score for graft rejection, requires neither extensive preparation nor deep anesthesia, is applicable to animals of all genetic background, discourages ischemic necrosis, and permits chemical and biological intervention. 
In general, both CD4+ and CD8+ allogeneic T cells are responsible for the rejection of allografts since they recognize mismatched major histocompatibility antigens from different mouse strains. Several models have been described for activating allogeneic T cells in skin-transplanted mice. The identification of major histocompatibility complex (MHC) class I and II molecules in different mouse strains including C57BL/6 mice was an important step toward understanding and studying T cell-mediated alloresponses. In the tail-skin transplantation model described here, a three-point mutation (I-Abm12) in the antigen-presenting groove of the MHC-class II (I-Ab) molecule is sufficient to induce strong allogeneic CD4+ T cell activation in C57BL/6 mice. Skin grafts from I-Abm12 mice on C57BL/6 mice are rejected within 12-15 days, while syngeneic grafts are accepted for up to 100 days. The absence of T cells (CD3-/- and Rag2-/- mice) allows skin graft acceptance up to 100 days, which can be overcome by transferring 2 x 104 wild type or transgenic T cells. Adoptively transferred T cells proliferate and produce IFN-&#947; in I-Abm12-transplanted Rag2-/- mice.

Tail-skin transplantation is a powerful model for studying T cell-dependent rejection and tolerance induction during allogeneic immune responses in mice. The advantages of this protocol are minor invasive surgery, and ease of monitoring with no need to sacrifice the recipient mouse.

The study of T cell responses and their consequences during allo-antigen recognition requires a model that enables one to distinguish between donor and ...

Mouse Na&#239;ve CD4+ T Cell Isolation and In vitro Differentiation into T Cell Subsets

Antigen inexperienced (na&#239;ve) CD4+ T cells undergo expansion and differentiation to effector subsets at the time of T cell receptor (TCR) recognition of cognate antigen presented on MHC class II. The cytokine signals present in the environment at the time of TCR activation are a major factor in determining the effector fate of a na&#239;ve CD4+ T cell. Although the cytokine environment during na&#239;ve T cell activation may be complex and involve both redundant and opposing signals in vivo, the addition of various cytokine combinations during naive CD4+ T cell activation in vitro can readily promote the establishment of effector T helper lineages with hallmark cytokine and transcription factor expression. Such differentiation experiments are commonly used as a first step for the evaluation of targets believed to promote or inhibit the development of certain CD4+ T helper subsets. The addition of mediators, such as signaling agonists, antagonists, or other cytokines, during the differentiation process can also be used to study the influence of a particular target on T cell differentiation. Here, we describe a basic protocol for the isolation of na&#239;ve T cells from mouse and the subsequent steps necessary for polarizing na&#239;ve cells to various T helper effector lineages in vitro.

Mouse Na&amp;#239;ve CD4+ T Cell Isolation and In vitro Differentiation into T Cell Subsets

Na&#239;ve CD4+ T cells polarize to various subsets depending on the environment at the time of activation. The differentiation of na&#239;ve CD4+ T cells to various effector subsets can be achieved in vitro through the addition of T cell receptor stimuli and specific cytokine signals.

Antigen inexperienced (na&#239;ve) CD4+ T cells undergo expansion and differentiation to effector subsets at the time of T cell receptor (TCR) recognition ...

In Vitro Differentiation of Human CD4+FOXP3+ Induced Regulatory T Cells (iTregs) from Na&#239;ve CD4+ T Cells Using a TGF-&#946;-containing Protocol

Regulatory T cells (Tregs) are an integral part of peripheral tolerance, suppressing immune reactions against self-structures and thus preventing autoimmune diseases. Clinical approaches to adoptively transfer Tregs, or to deplete Tregs in cancer, are underway with promising first outcomes. 
Because the number of naturally occurring Tregs (nTregs) is very limited, studying certain Treg features using in vitro induced Tregs (iTregs) can be advantageous. To date, the best although not absolutely specific protein marker to delineate Tregs is the transcription factor FOXP3. Despite the importance of Tregs including non-redundant roles of peripherally induced Tregs, the protocols to generate iTregs are currently controversial, particularly for human cells. This protocol therefore describes the in vitro differentiation of human CD4+FOXP3+ iTregs from human na&#239;ve T cells using a range of Treg-inducing factors (TGF-&#946; plus IL-2 only, or their combination with retinoic acid, rapamycin or butyrate) in parallel. It also describes the phenotyping of these cells by flow cytometry and qRT-PCR. 
These protocols result in reproducible expression of FOXP3 and other Treg signature genes and enable the study of general FOXP3-regulatory mechanisms as well as protocol-specific effects to delineate the impact of certain factors. iTregs can be utilized to study various phenotypic aspects as well as molecular mechanisms of Treg induction. Detailed molecular studies are facilitated by relatively large cell numbers that can be obtained. 
A limitation for the application of iTregs is the relative instability of FOXP3 expression in these cells compared to nTregs. iTregs generated by these protocols can also be used for functional assays such as studying their suppressive function, in which iTregs induced by TGF-&#946; plus retinoic acid and rapamycin display superior suppressive activity. However, the suppressive capacity of iTregs can differ from nTregs and the use of appropriate controls is crucial.

&lt;em&gt;In Vitro&lt;/em&gt; Differentiation of Human CD4&lt;sup&gt;+&lt;/sup&gt;FOXP3&lt;sup&gt;+&lt;/sup&gt; Induced Regulatory T Cells (iTregs) from Na&amp;#239;ve CD4&lt;sup&gt;+&lt;/sup&gt; T Cells Using a TGF-&amp;#946;-containing Protocol

This protocol describes the reproducible generation and phenotyping of human induced regulatory T cells (iTregs) from na&#239;ve CD4+ T cells in vitro. Different protocols for FOXP3 induction allow for the study of specific iTreg phenotypes obtained with respective protocols.