Name: an in vivo mouse model to measure na&#239;ve cd4 t cell activation, proliferation and th1 differentiation induced by bone marrow-derived dendritic cells
Uploaded: 2018-08-22T15:00:00
Description: Watch this Scientific Journal Video about An In Vivo Mouse Model to Measure NaÃ¯ve CD4 T Cell Activation, Proliferation and Th1 Differentiation Induced by Bone Marrow-derived Dendritic Cells at JoVE

We thank Dr. Simon Bartlett for English editing. This study was supported by grants from Instituto de Salud Carlos III (ISCIII) (PI14/00526; PI17/01395; CP11/00145; CPII16/00022), the Miguel Servet Program and Fundaci&#243;n Ram&#243;n Areces; with co-funding from the Fondo Europeo de Desarrollo Regional (FEDER). The CNIC is supported by the Ministry of Economy, Industry and Competitiveness (MEIC), and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015-0505). RTF is founded by Fundaci&#243;n Ram&#243;n Areces and CNIC, VZG by ISCIII, BHF by Instituto de Investigaci&#243;n Sanitaria Hospital 12 de Octubre (imas12) and JMG-G by the ISCIII Miguel Servet Program and imas12.

Experimental procedures were approved by the Fundaci&#243;n Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) and the Comunidad Aut&#243;noma de Madrid in accordance with Spanish and European guidelines. Mice were bred in specific pathogen free (SPF) conditions and were euthanized by carbon dioxide (CO2) inhalation.
1. Isolation of Mouse Bone Marrow Cells from Tibias and Femurs
NOTE: The C57BL/6 congenic mouse strain carries the differen...

<ol>
	<li>Zhu, J., Yamane, H., Paul, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differentiation+of+effector+CD4+T+cell+populations+(*).">Differentiation of effector CD4 T cell populations (*).</a> Annual Review of Immunology. 28, 445-489 (2010).</li><li>Bustos-Moran, E., Blas-Rus, N., Martin-Cofreces, N. B., Sanchez-Madrid, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orchestrating+Lymphocyte+Polarity+in+Cognate+Immune+Cell-Cell+Interactions.">Orchestrating Lymphocyte Polarity in Cognate Immune Cell-Cell Interactions.</a> International Review of Cell and Molecular Biology. 327, 195-261 (2016).</li><li>Gonzalez-Granado, J. 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=Nuclear+envelope+lamin-A+couples+actin+dynamics+with+immunological+synapse+architecture+and+T+cell+activation.">Nuclear envelope lamin-A couples actin dynamics with immunological synapse architecture and T cell activation.</a> Science Signaling. 7 (322), ra37 (2014).</li><li>Rocha-Perugini, V., Gonzalez-Granado, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nuclear+envelope+lamin-A+as+a+coordinator+of+T+cell+activation.">Nuclear envelope lamin-A as a coordinator of T cell activation.</a> Nucleus. 5 (5), 396-401 (2014).</li><li>Rocha-Perugini, 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=CD9+Regulates+Major+Histocompatibility+Complex+Class+II+Trafficking+in+Monocyte-Derived+Dendritic+Cells.">CD9 Regulates Major Histocompatibility Complex Class II Trafficking in Monocyte-Derived Dendritic Cells.</a> Molecular and Cellular Biology. 37 (15), (2017).</li><li>Kaech, S. M., Wherry, E. J., Ahmed, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effector+and+memory+T-cell+differentiation:+implications+for+vaccine+development.">Effector and memory T-cell differentiation: implications for vaccine development.</a> Nature Reviews Immunology. 2 (4), 251-262 (2002).</li><li>Iborra, S., Gonzalez-Granado, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Vitro+Differentiation+of+Naive+CD4(+)+T+Cells:+A+Tool+for+Understanding+the+Development+of+Atherosclerosis.">In Vitro Differentiation of Naive CD4(+) T Cells: A Tool for Understanding the Development of Atherosclerosis.</a> Methods in Molecular Biology. 1339, 177-189 (2015).</li><li>Toribio-Fernandez, R., 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=Lamin+A/C+augments+Th1+differentiation+and+response+against+vaccinia+virus+and+Leishmania+major.">Lamin A/C augments Th1 differentiation and response against vaccinia virus and Leishmania major.</a> Cell Death &amp; Disease. 9 (1), 9 (2018).</li><li>Lee, T., Shevchenko, I., Sprouse, M. L., Bettini, M., Bettini, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Retroviral+Transduction+of+Bone+Marrow+Progenitor+Cells+to+Generate+T-cell+Receptor+Retrogenic+Mice.">Retroviral Transduction of Bone Marrow Progenitor Cells to Generate T-cell Receptor Retrogenic Mice.</a> Journal of Visualized Experiments. (113), (2016).</li><li>Cruz-Adalia, 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=Conventional+CD4(+)+T+cells+present+bacterial+antigens+to+induce+cytotoxic+and+memory+CD8(+)+T+cell+responses.">Conventional CD4(+) T cells present bacterial antigens to induce cytotoxic and memory CD8(+) T cell responses.</a> Nature Communications. 8 (1), 1591 (2017).</li><li>Quah, B. J., Wijesundara, D. K., Ranasinghe, C., Parish, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+fluorescent+target+arrays+for+assessment+of+T+cell+responses+in+vivo.">The use of fluorescent target arrays for assessment of T cell responses in vivo.</a> Journal of Visualized Experiments. (88), e51627 (2014).</li><li>Cruz-Adalia, A., Ramirez-Santiago, G., Torres-Torresano, M., Garcia-Ferreras, R., Veiga Chacon, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T+Cells+Capture+Bacteria+by+Transinfection+from+Dendritic+Cells.">T Cells Capture Bacteria by Transinfection from Dendritic Cells.</a> Journal of Visualized Experiments. (107), e52976 (2016).</li><li>Cossarizza, 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=Guidelines+for+the+use+of+flow+cytometry+and+cell+sorting+in+immunological+studies.">Guidelines for the use of flow cytometry and cell sorting in immunological studies.</a> European Journal of Immunology. 47 (10), 1584-1797 (2017).</li><li>Quah, B. J., Parish, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+and+improved+methods+for+measuring+lymphocyte+proliferation+in+vitro+and+in+vivo+using+CFSE-like+fluorescent+dyes.">New and improved methods for measuring lymphocyte proliferation in vitro and in vivo using CFSE-like fluorescent dyes.</a> Journal of Immunological Methods. 379 (1-2), 1-14 (2012).</li><li>Yardeni, T., Eckhaus, M., Morris, H. D., Huizing, M., Hoogstraten-Miller, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Retro-orbital+injections+in+mice.">Retro-orbital injections in mice.</a> Lab Animals (NY). 40 (5), 155-160 (2011).</li><li>Warth, S. C., Heissmeyer, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adenoviral+transduction+of+naive+CD4+T+cells+to+study+Treg+differentiation.">Adenoviral transduction of naive CD4 T cells to study Treg differentiation.</a> Journal of Visualized Experiments. (78), (2013).</li><li>Liou, H. L., Myers, J. T., Barkauskas, D. S., Huang, A. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intravital+imaging+of+the+mouse+popliteal+lymph+node.">Intravital imaging of the mouse popliteal lymph node.</a> Journal of Visualized Experiments. (60), (2012).</li></ol>

This protocol allows for the characterization of the capacity of BM-derived DCs to modulate the activation, proliferation, and differentiation of na&#239;ve CD4 T cells. Moreover, it can also be used to assess the susceptibility of CD4 T cells to modulation by BM-derived DCs. With this protocol, changes in these events can be measured in vivo.
Depending on the hypothesis under investigation, several combinations of T cells and DCs can be used. For example, one can analyze the conseque...

CD4 T cells and antigen presenting cells (APCs) such as DCs are required mediators of immunity to microbial pathogens1,2. In peripheral lymphoid organs, CD4 T cells are activated upon recognition of specific antigens presented by APCs3,4,5. Activated CD4 T cells proliferate and differentiate into distinct specific effector Th cells that are necessary for the development of a correct adaptive immune response6,7. Control of these processes is critical for producing an adequate adaptive defense that kills the pathogen without producing harmful tissue damage8. Th cells are defined according to the expression or production of surface molecules, transcription factors, and effector cytokines and perform essential and precise functions in response to pathogens1. Cells of the Th1 cell subset express the transcription factor T-bet and the cytokine interferon &#947; (IFN&#947;) and participate in host defense against intracellular pathogens1. Quantification of na&#239;ve CD4 T cell activation, proliferation, and Th1 differentiation is a useful means of assessing the role T cells play in an immune response.
This protocol enables in vivo analysis of the capacity of in vitro-generated BM-derived DCs to modulate the activation, proliferation, and Th1 differentiation of na&#239;ve CD4 T cells. The protocol also serves to assess the capacity of na&#239;ve CD4 T cells to be activated, induced to proliferate, and Th1 differentiated (Figure 1). This versatile protocol circumvents the inability to specifically manipulate or select the studied cell population in purely in vivo protocols. The effects of diverse molecules and treatments on DCs can be studied by using BM from genetically modified mice5 or by treating or genetically manipulating isolated BM cells9. Similarly, T cell responses can be explored by obtaining T cells for adoptive transfer from different sources or after several manipulations3,8,10.
The main advantages of this protocol are twofold. T cell activation, proliferation, and Th1 differentiation are analyzed with a flow cytometry approach; and this is combined with in vivo studies, thus averting alterations that may occur in vitro and including cell types and other factors only found in intact organs11.
The use of vital dyes is a widely used technique to track cell proliferation while avoiding the use of radioactivity. The measurement of proliferation with these reagents is based on dye dilution after cell division. Moreover, these dyes can be detected at multiple wavelengths and are easily analyzed by flow cytometry in combination with multiple fluorescent antibodies or markers. We highlight the utility of this protocol by showing how T cell activation, proliferation, and Th1 differentiation can be analyzed by flow cytometry.

<table>
	<tbody>
		<tr>
			<td>Ethanol</td>
			<td>VWR Chemicals</td>
			<td>20,824,365</td>
			<td>5 L</td>
		</tr>
		<tr>
			<td>Scissors</td>
			<td>Fine Science Tools (F.S.T.)</td>
			<td>14001-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Forceps</td>
			<td>Fine Science Tools (F.S.T.)</td>
			<td>11000-13</td>
			<td></td>
		</tr>
		<tr>
			<td>Fine Forceps</td>
			<td>Fine Science Tools (F.S.T.)</td>
			<td>11253-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Scalpel</td>
			<td>Fine Science Tools (F.S.T.)</td>
			<td>10020-00</td>
			<td>Box of 100 blades</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>SIGMA</td>
			<td>F7524</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin/streptomycin</td>
			<td>LONZA</td>
			<td>DE17-602E</td>
			<td></td>
		</tr>
		<tr>
			<td>Roswell Park Memorial Institute medium (RPMI)</td>
			<td>GIBCO</td>
			<td>21875-034</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile Petri dishes</td>
			<td>Falcon</td>
			<td>353003</td>
			<td></td>
		</tr>
		<tr>
			<td>25-gauge needle</td>
			<td>BD Microlance 3</td>
			<td>300600</td>
			<td></td>
		</tr>
		<tr>
			<td>1 ml syringe</td>
			<td>Novico</td>
			<td>N15663</td>
			<td></td>
		</tr>
		<tr>
			<td>15 ml conical tubes</td>
			<td>Falcon</td>
			<td>352096</td>
			<td></td>
		</tr>
		<tr>
			<td>50 ml conical tubes</td>
			<td>Falcon</td>
			<td>352098</td>
			<td></td>
		</tr>
		<tr>
			<td>70 &#956;m nylon web filter</td>
			<td>BD Falcon</td>
			<td>352350</td>
			<td></td>
		</tr>
		<tr>
			<td>Red blood lysis buffer</td>
			<td>SIGMA</td>
			<td>R7757</td>
			<td>100 Ml</td>
		</tr>
		<tr>
			<td>EDTA</td>
			<td>SIGMA</td>
			<td>ED2SS-250</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin</td>
			<td>SIGMA</td>
			<td>A7906</td>
			<td>100 g</td>
		</tr>
		<tr>
			<td>Trypan blue</td>
			<td>SIGMA</td>
			<td>302643-25G</td>
			<td></td>
		</tr>
		<tr>
			<td>Culture-plates</td>
			<td>Falcon</td>
			<td>353003</td>
			<td></td>
		</tr>
		<tr>
			<td>4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES)</td>
			<td>Cambrex</td>
			<td>BE17-737E</td>
			<td></td>
		</tr>
		<tr>
			<td>Beta-mercaptoethanol</td>
			<td>Merck</td>
			<td>8-05740-0250</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium pyruvate</td>
			<td>LONZA</td>
			<td>BE13-115E</td>
			<td></td>
		</tr>
		<tr>
			<td>L-glutamine</td>
			<td>LONZA</td>
			<td>BE17-605E</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant murine Granulocyte Macrophage colony-stimulating factor (GM-CSF)</td>
			<td>Prepotech</td>
			<td>315-03</td>
			<td></td>
		</tr>
		<tr>
			<td>lipopolysaccharide (LPS)</td>
			<td>SIGMA-ALDRICH</td>
			<td>L2018</td>
			<td></td>
		</tr>
		<tr>
			<td>96-well-plate</td>
			<td>Costar</td>
			<td>3799</td>
			<td></td>
		</tr>
		<tr>
			<td>v450 anti-mouse CD11b antibody</td>
			<td>BD Biosciences</td>
			<td>560455</td>
			<td></td>
		</tr>
		<tr>
			<td>PE anti-mouse CD64 antibody</td>
			<td>BioLegend</td>
			<td>139303</td>
			<td></td>
		</tr>
		<tr>
			<td>PE anti-mouse CD115 antibody</td>
			<td>BioLegend</td>
			<td>135505</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC anti-mouse CD11c antibody</td>
			<td>BioLegend</td>
			<td>117305</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC anti-mouse MHCII antibody</td>
			<td>BioLegend</td>
			<td>125507</td>
			<td></td>
		</tr>
		<tr>
			<td>APC anti-mouse CD86 antibody</td>
			<td>BioLegend</td>
			<td>105011</td>
			<td></td>
		</tr>
		<tr>
			<td>APC anti-mouse CD80 antibody</td>
			<td>BioLegend</td>
			<td>104713</td>
			<td></td>
		</tr>
		<tr>
			<td>Flow Cytometry tubes</td>
			<td>Zelian</td>
			<td>300800-1</td>
			<td>PS 12X75 5mL</td>
		</tr>
		<tr>
			<td>OTII Ovoalbumine peptide</td>
			<td>InvivoGen</td>
			<td>323-339</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated CD8&#945; antibody</td>
			<td>Tonbo Biosciences</td>
			<td>30-0081-U500</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated IgM antibody</td>
			<td>BioLegend</td>
			<td>406503</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated B220 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>30-0452-U500</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated CD19 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>30-0193-U500</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated MHCII (I-Ab) antibody</td>
			<td>BioLegend</td>
			<td>115302</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated CD11b antibody</td>
			<td>Tonbo Biosciences</td>
			<td>30-0112-U500</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated CD11c antibody</td>
			<td>BioLegend</td>
			<td>117303</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated CD44 antibody</td>
			<td>BioLegend</td>
			<td>103003</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated CD25 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>30-0251-U100</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-mouse biotinylated DX5 antibody</td>
			<td>BioLegend</td>
			<td>108903</td>
			<td></td>
		</tr>
		<tr>
			<td>streptavidin-coated magnetic microbeads</td>
			<td>MACS Miltenyi Biotec</td>
			<td>130-048-101</td>
			<td></td>
		</tr>
		<tr>
			<td>Magnetic cell separator</td>
			<td>MACS Miltenyi Biotec</td>
			<td>130-090-976</td>
			<td>QuadroMACS Separator</td>
		</tr>
		<tr>
			<td>Separation columns</td>
			<td>MACS Miltenyi Biotec</td>
			<td>130-042-401</td>
			<td></td>
		</tr>
		<tr>
			<td>PE anti-mouse CD4 antibody</td>
			<td>BioLegend</td>
			<td>100408</td>
			<td></td>
		</tr>
		<tr>
			<td>APC anti-mouse CD3 antibody</td>
			<td>BioLegend</td>
			<td>100235</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC anti-mouse CD8 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>35-0081-U025</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell Violet Tracer</td>
			<td>Thermofisher</td>
			<td>C34557</td>
			<td></td>
		</tr>
		<tr>
			<td>APC anti-mouse CD25 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>20-0251-U100</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa647 anti-mouse CD69 antibody</td>
			<td>BioLegend</td>
			<td>104518</td>
			<td></td>
		</tr>
		<tr>
			<td>PerCPCY5.5 anti-mouse CD45.1 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>65-0453</td>
			<td></td>
		</tr>
		<tr>
			<td>APC anti-mouse CD45.1 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>20-0453</td>
			<td></td>
		</tr>
		<tr>
			<td>PECY7 anti-mouse CD45.1 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>60-0453</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC anti-mouse CD45.2 antibody</td>
			<td>Tonbo Biosciences</td>
			<td>35-0454</td>
			<td></td>
		</tr>
		<tr>
			<td>Ionomycin</td>
			<td>SIGMA-ALDRICH</td>
			<td>I0634</td>
			<td></td>
		</tr>
		<tr>
			<td>Phorbol 12 Myristate 13 Acetate (PMA)</td>
			<td>SIGMA</td>
			<td>P8139</td>
			<td></td>
		</tr>
		<tr>
			<td>Brefeldin A (BD GolgiPlug)</td>
			<td>BD</td>
			<td>555029</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraformaldehyde</td>
			<td>Millipore</td>
			<td>8-18715-02100</td>
			<td></td>
		</tr>
		<tr>
			<td>Intracellular permeabilization buffer</td>
			<td>eBioscience</td>
			<td>00-8333</td>
			<td></td>
		</tr>
		<tr>
			<td>APC anti-mouse IFNg antibody</td>
			<td>Tonbo Biosciences</td>
			<td>20-7311-U100</td>
			<td></td>
		</tr>
		<tr>
			<td>Fc-block (anti-mouse CD16/CD32)</td>
			<td>Tonbo Biosciences</td>
			<td>70-0161-U100</td>
			<td></td>
		</tr>
		<tr>
			<td>B6.SJL CD45.1 mice</td>
			<td>The Jackson Laboratory</td>
			<td>002014</td>
			<td></td>
		</tr>
		<tr>
			<td>BD LSRFortessa&#8482; Cell Analyzer</td>
			<td>BD Biosciences</td>
			<td>649225</td>
			<td></td>
		</tr>
		<tr>
			<td>DAPI Solution</td>
			<td>Thermofisher</td>
			<td>62248</td>
			<td></td>
		</tr>
	</tbody>
</table>

an in vivo mouse model to measure na&#239;ve cd4 t cell activation, proliferation and th1 differentiation induced by bone marrow-derived dendritic cells

Quantification of na&#239;ve CD4 T cell activation, proliferation, and differentiation to T helper 1 (Th1) cells is a useful way to assess the role played by T cells in an immune response. This protocol describes the in vitro differentiation of bone marrow (BM) progenitors to obtain granulocyte macrophage colony-stimulating factor (GM-CSF) derived-dendritic cells (DCs). The protocol also describes the adoptive transfer of ovalbumin peptide (OVAp)-loaded GM-CSF-derived DCs and na&#239;ve CD4 T cells from OTII transgenic mice in order to analyze the in vivo activation, proliferation, and Th1 differentiation of the transferred CD4 T cells. This protocol circumvents the limitation of purely in vivo methods imposed by the inability to specifically manipulate or select the studied cell population. Moreover, this protocol allows studies in an in vivo environment, thus avoiding alterations to functional factors that may occur in vitro and including the influence of cell types and other factors only found in intact organs. The protocol is a useful tool for generating changes in DCs and T cells that modify adaptive immune responses, potentially providing important results to understand the origin or development of numerous immune associated diseases.

Figure 1 illustrates the steps described in this protocol. Figure 2 illustrates the isolation and culture of mouse BM cells. The addition of GM-CSF and LPS to these cultures allows the in vitro generation and maturation of DCs. Figure 3 illustrates the flow cytometry analysis of the differentiation and maturation of the obtained DCs. OVAp-loaded GM-CSF BM-derived DCs and isolated vital cell ...

Watch this Scientific Journal Video about An In Vivo Mouse Model to Measure NaÃ¯ve CD4 T Cell Activation, Proliferation and Th1 Differentiation Induced by Bone Marrow-derived Dendritic Cells at JoVE

An &lt;em&gt;In Vivo&lt;/em&gt; Mouse Model to Measure Na&amp;#239;ve CD4 T Cell Activation, Proliferation and Th1 Differentiation Induced by Bone Marrow-derived Dendritic Cells

Here, we present a protocol for the in vivo determination of na&#239;ve CD4 T cell (T cell) activation, proliferation, and Th1 differentiation induced by GM-CSF bone marrow (BM)-derived dendritic cells (DCs). In addition, this protocol describes BM and T-cell isolation, DC generation, and DC and T-cell adoptive transfer.

An In Vivo Mouse Model to Measure Na&#239;ve CD4 T Cell Activation, Proliferation and Th1 Differentiation Induced by Bone Marrow-derived Dendritic Cells

Quantification of na&#239;ve CD4 T cell activation, proliferation, and differentiation to T helper 1 (Th1) cells is a useful way to assess the role played ...

This method can help answer key questions in the immunology field about T-cell activation, proliferation, and Th1 differentiation, as well antigen presenting cell stimulation of adaptive immunity. The main advantage of this technique is that it allows the study of an in vivo environment while simultaneously allowing cell manipulation in vitro. Visual demonstration of this method is critical as the organ and bone isolation and adoptive transfer steps are difficult to master through text instructions alone.For bone marrow cell isolation, disinfect the hind limbs of an adult mouse with 70%ethanol and use scissors to make a lateral skin incision across the hind limbs. Insert scissors at the medial aspect of the legs, and cut the skin with the scissors until the beginning of the hind limbs. Then use forceps to separate the skin from the legs.Using scissors, separate the muscle from the femur and tibia, and use scissors to disarticulate the hip joint, breaking the femur head. Then separate the femure from the tibia without breaking the bone ends, and place the bones in a petri dish of complete medium on ice. When all of the bones have been harvested, carefully cut off the proximal and distal ends of each bone with a scalpel, and use a 1 millileter syringe equipped with a 25-guage needle to flush the bones repeatedly with a total volume of 10 millileters of warm complete RPMI medium.When all of the bones have been flushed, transfer the entire contents of the dish to a 50-millileter conical tube fitted with a 70-micrometer pore nylon web filter, and carefully dislodge any debris and cell conglomerates with gentle stirring and pipetting. Collect the bone marrow cells by centrifugation. Resuspend the pellet in one millileter of four-degree Celsius red blood cell lysis buffer with pipetting, and incubate the mix on ice for five minutes.At the end of the incubation, stop the lysis with 10 millileter of PVS, and resuspend the pellet in 25 millileters of complete medium for a second centrifugation. Then resuspend the cells in 5 millileters of fresh complete medium for counting, and centrifuge the cells again. For secondary lymphoid tissue cell isolation, collect the inguinal, axillary, brachial, cervical, and mesentaric lymph nodes, and spleen from OT-II transgenic mice, and transfer the secondary lymphoid tissues into a plastic petri dish containing 10 millileters of complete RPMI medium.When all of the tissues have been harvested, transfer the lymph nodes and spleen to a 70-micrometer cell strainer in a 50-millileter conical tube, and use a syringe plunger to homogenize the tissues. Flush the strainer with up to 15 millileters of medium, and spin down the cells by centrifugation. Then isolate the CD4-positive T cells by magnetic bead sorting, according to standard protocols.For in vivo activation of the naive OT-II CD4-positive T-cells, label the magnetic bead-isolated T-cells with vital cell tracer dye, according to standard protocols, and resuspend the labeled cells at a 10 to the sixth cells per 100 microliters of PBS concentration. Then adoptively transfer 100 microliters of cells per animal via the tail vein. Pre-warm the mice before the injection in order to ensure that the tail veins are enough dilated to allow delivery of entire cell volume.After 24 hours, deliver 10 to the fifth LPS-matured OVA peptide-loaded dendritic cells by subcutaneous injection into the foot pad of each T-cell injected animal. Two and five days after the adoptive challenge, harvest the poplitial lymph nodes from the recipient animals for tissue processing and T-cell isolation, as demonstrated. To analyze T-cell activation, stain day two-isolated cells with fluorescent antibodies against CD4, CD69, and CD25 to determine the percentage of CD64-positive, CD25-positive T-cells within the recipient CD4-positive population by flow cytometry.To assess T-cell proliferation, stain day five-isolated cells with the appropriate fluorescent antibodies against CD4, and analyze the decay of the vital cell tracer dye signal in the donor CD4-positive T-cell population by flow cytometry. To evaluate Th1 differentiation, plate four times 10 to the fifth day five-isolated T-cells per well in 200 microliters of complete medium, supplemented with ionomycin and PMA per well, in a 96-well plate. Then place the plate in a 37 degree Celsius cell culture incubator for six hours, adding Brefeldin A to each well to block cytokine secretion during the last four hours of the stimulation.At the end of the incubation, centrifuge the plate, and discard the supernatant by rapid inversion. Stain the cells with anti-CD4 antibody, followed by fixation in 100 microliters of 2%paraformaldehyde and 1%sucrose for 20 minutes at room temperature. Permeabilize the cells with 50 microliters of permeabilization buffer for 30 minutes at 4 degrees Celsius, followed by a centrifugation wash with 150 microliters of PBS per well.Next, stain for the intracellular cytokines of interest, according to standard protocols for 30 minutes at room temperature, followed by two centrifugation washes with 150 microliters of PBS supplemented with 1%saponin per well. Then, analyze the cells by flow cytometry. Flow cytometric analysis of GM-CSF bone marrow-derived dendritic cells after LPS stimulation, reveals an upregulation of maturation markers, such as MHCII, CD80, and CD86.Naive CD4 positive OT-II T-cells become activated after adoptive transfer to recipient animals by their upregulation of T-cell activation markers surface expression, and multiple rounds of cell division. Upon activation, the proliferating CD-positive OT-II T-cells demonstrate a Th1 phenotype, as demonstrated by their intracellular interferon gamma expression. Once mastered, this technique can be completed in eight hours if it's performed properly.While attempting this procedure, it's important to remember to prepare all the reagents and materials the day before the experiment. After its development, this technique paved the way for researchers in immunology to study dendritic cells and T-cells in mice. After watching this video, you should have a good understanding of how to isolate bone marrow from the femurs and tibia of mice, and how to transfer T-cells and dendritic cells to recipient animals.Don't forget that working with sharp instruments such needles, scalpels, or scissors, can be extremely hazardous, so precautions such as using the appropriate finger protection should always be taken while performing these procedures.

an-vivo-mouse-model-to-measure-naive-cd4-t-cell-activation

Research

JoVE Journal

Immunology and Infection

Generation and Labeling of Murine Bone Marrow-derived Dendritic Cells with Qdot Nanocrystals for Tracking Studies

Dendritic cells (DCs) are professional antigen presenting cells (APCs) found in peripheral tissues and in immunological organs such as thymus, bone marrow, spleen, lymph nodes and Peyer's patches 1-3. DCs present in peripheral tissues sample the organism for the presence of antigens, which they take up, process and present in their surface in the context of major histocompatibility molecules (MHC). Then, antigen-loaded DCs migrate to immunological organs where they present the processed antigen to T lymphocytes triggering specific immune responses. One way to evaluate the migratory capabilities of DCs is to label them with fluorescent dyes 4.
Herewith we demonstrate the use of Qdot fluorescent nanocrystals to label murine bone marrow-derived DC. The advantage of this labeling is that Qdot nanocrystals possess stable and long lasting fluorescence that make them ideal for detecting labeled cells in recovered tissues. To accomplish this, first cells will be recovered from murine bone marrows and cultured for 8 days in the presence of granulocyte macrophage-colony stimulating factor in order to induce DC differentiation. These cells will be then labeled with fluorescent Qdots by short in vitro incubation. Stained cells can be visualized with a fluorescent microscopy. Cells can be injected into experimental animals at this point or can be into mature cells upon in vitro incubation with inflammatory stimuli. In our hands, DC maturation did not determine loss of fluorescent signal nor does Qdot staining affect the biological properties of DCs. Upon injection, these cells can be identified in immune organs by fluorescent microscopy following typical dissection and fixation procedures.

Dendritic cells uptake antigens and migrate towards immune organs to present processed antigens to T cells. Qdot nanocrystal labeling provides a long-lasting and stable fluorescent signal. This allows tracking of dendritic cells to different organs by fluorescent microscopy.

Dendritic cells (DCs) are professional antigen presenting cells (APCs) found in peripheral tissues and in immunological organs such as thymus, bone ...

Adenoviral Transduction of Naive CD4 T Cells to Study Treg Differentiation

Regulatory T cells (Tregs) are essential to provide immune tolerance to self as well as to certain foreign antigens. Tregs can be generated from naive CD4 T cells in vitro with TCR- and co-stimulation in the presence of TGF&beta; and IL-2. This bears enormous potential for future therapies, however, the molecules and signaling pathways that control differentiation are largely unknown.
Primary T cells can be manipulated through ectopic gene expression, but common methods fail to target the most important naive state of the T cell prior to primary antigen recognition. Here, we provide a protocol to express ectopic genes in naive CD4 T cells in vitro before inducing Treg differentiation. It applies transduction with the replication-deficient adenovirus and explains its generation and production. The adenovirus can take up large inserts (up to 7 kb) and can be equipped with promoters to achieve high and transient overexpression in T cells. It effectively transduces naive mouse T cells if they express a transgenic Coxsackie adenovirus receptor (CAR). Importantly, after infection the T cells remain naive (CD44low, CD62Lhigh) and resting (CD25-, CD69-) and can be activated and differentiated into Tregs similar to non-infected cells. Thus, this method enables manipulation of CD4 T cell differentiation from its very beginning. It ensures that ectopic gene expression is already in place when early signaling events of the initial TCR stimulation induces cellular changes that eventually lead into Treg differentiation.

Adenoviral gene transfer into naive CD4 T cells with transgenic expression of the Coxsackie adenovirus receptor enables the molecular analysis of regulatory T cell differentiation in vitro.

Regulatory T cells (Tregs) are essential to provide immune tolerance to self as well as to certain foreign antigens. Tregs can be generated from naive CD4 ...

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 ...

Assessing the Innate Sensing of HIV-1 Infected CD4+ T Cells by Plasmacytoid Dendritic Cells Using an Ex vivo Co-culture System.

HIV-1 innate sensing requires direct contact of infected CD4+ T cells with plasmacytoid dendritic cells (pDCs). In order to study this process, the protocols described here use freshly isolated human peripheral blood mononuclear cells (PBMCs) or plasmacytoid dendritic cells (pDCs) to sense infections in either T cell line (MT4) or heterologous primary CD4+ T cells. In order to ensure proper sensing, it is essential that PBMC are isolated immediately after blood collection and that optimal percentage of infected T cells are used. Furthermore, multi-parametric flow cytometric staining can be used to confirm that PBMC samples contain the different cell lineages at physiological ratios. A number of controls can also be included to evaluate viability and functionality of pDCs. These include, the presence of specific surface markers, assessing cellular responses to known agonist of Toll-Like Receptors (TLR) pathways, and confirming a lack of spontaneous type-I interferon (IFN) production. In this system, freshly isolated PBMCs or pDCs are co-cultured with HIV-1 infected cells in 96 well plates for 18-22 hr. Supernatants from these co-cultures are then used to determine the levels of bioactive type-I IFNs by monitoring the activation of the ISGF3 pathway in HEK-Blue IFN-&#945;/&#946; cells. Prior and during co-culture conditions, target cells can be subjected to flow cytometric analysis to determine a number of parameters, including the percentage of infected cells, levels of specific surface markers, and differential killing of infected cells. Although, these protocols were initially developed to follow type-I IFN production, they could potentially be used to study other imuno-modulatory molecules released from pDCs and to gain further insight into the molecular mechanisms governing HIV-1 innate sensing.

Assessing the Innate Sensing of HIV-1 Infected CD4+ T Cells by Plasmacytoid Dendritic Cells Using an Ex vivo Co-culture System.

Unlike cell-free HIV-1 particles, infected CD4+ T cells are effectively sensed by plasmacytoid dendritic cells (pDCs). This manuscript describes a method where peripheral blood mononuclear cells (PBMCs) or isolated pDCs are co-cultured with HIV-1 infected T cells to evaluate innate sensing by pDCs as assessed by release of type-I IFN.

HIV-1 innate sensing requires direct contact of infected CD4+ T cells with plasmacytoid dendritic cells (pDCs). In order to study this process, the ...

Isolation and Intravenous Injection of Murine Bone Marrow Derived Monocytes

As a subtype of leukocytes and progenitors of macrophages, monocytes are involved in many important processes of organisms and are often the subject of various fields in biomedical science. The method described below is a simple and effective way to isolate murine monocytes from heterogeneous bone marrow.
Bone marrow from the femur and tibia of Balb/c mice is harvested by flushing with phosphate buffered saline (PBS). Cell suspension is supplemented with macrophage-colony stimulating factor (M-CSF) and cultured on ultra-low attachment surfaces to avoid adhesion-triggered differentiation of monocytes. The properties and differentiation of monocytes are characterized at various intervals. Fluorescence activated cell sorting (FACS), with markers like CD11b, CD115, and F4/80, is used for phenotyping. At the end of cultivation, the suspension consists of 45%&#177; 12% monocytes. By removing adhesive macrophages, the purity can be raised up to 86%&#177; 6%. After the isolation, monocytes can be utilized in various ways, and one of the most effective and common methods for in vivo delivery is intravenous tail vein injection. 
This technique of isolation and application is important for mouse model studies, especially in the fields of inflammation or immunology. Monocytes can also be used therapeutically in mouse disease models.

Here we present a protocol that generates large amounts of murine monocytes from heterogeneous bone marrow for translational applications. In comparison to others, this new method helps reduce the number of sacrificed animals and lowers costs by avoiding expensive methods such as high gradient magnetic cell separation (MACS).

As a subtype of leukocytes and progenitors of macrophages, monocytes are involved in many important processes of organisms and are often the subject of ...

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 ...

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 ...

Isolation and Ex Vivo Culture of V&#948;1+CD4+&#947;&#948; T Cells, an Extrathymic &#945;&#946;T-cell Progenitor

The thymus, the primary organ for the generation of &#945;&#946; T cells and backbone of the adaptive immune system in vertebrates, has long been considered as the only source of &#945;&#946;T cells. Yet, thymic involution begins early in life leading to a drastically reduced output of na&#239;ve &#945;&#946;T cells into the periphery. Nevertheless, even centenarians can build immunity against newly acquired pathogens. Recent research suggests extrathymic &#945;&#946;T cell development, however our understanding of pathways that may compensate for thymic loss of function are still rudimental. &#947;&#948; T cells are innate lymphocytes that constitute the main T-cell subset in the tissues. We recently ascribed a so far unappreciated outstanding function to a &#947;&#948; T cell subset by showing that the scarce entity of CD4+ V&#948;1+&#947;&#948; T cells can transdifferentiate into &#945;&#946;T cells in inflammatory conditions. Here, we provide the protocol for the isolation of this progenitor from peripheral blood and its subsequent cultivation. V&#948;1 cells are positively enriched from PBMCs of healthy human donors using magnetic beads, followed by a second step wherein we target the scarce fraction of CD4+ cells with a further magnetic labeling technique. The magnetic force of the second labeling exceeds the one of the first magnetic label, and thus allows the efficient, quantitative and specific positive isolation of the population of interest. We then introduce the technique and culture condition required for cloning and efficiently expanding the cells and for identification of the generated clones by FACS analysis. Thus, we provide a detailed protocol for the purification, culture and ex vivo expansion of CD4+ V&#948;1+&#947;&#948; T cells. This knowledge is prerequisite for studies that relate to this &#945;&#946;T cell progenitor`s biology and for those who aim to identify the molecular triggers that are involved in its transdifferentiation.

Isolation and Ex Vivo Culture of V&amp;#948;1+CD4+&amp;#947;&amp;#948; T Cells, an Extrathymic &amp;#945;&amp;#946;T-cell Progenitor

Here, we provide an optimized protocol for the isolation and cloning of the scarce T-cell entity of peripheral V&#948;1+CD4+ T cells that is, as we showed recently, an extrathymic &#945;&#946; T-cell progenitor. This technique allows to quantitatively isolate, clone and efficiently expand these cells in ex vivo culture.

The thymus, the primary organ for the generation of &#945;&#946; T cells and backbone of the adaptive immune system in vertebrates, has long been ...

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.

Regulatory T cells (Tregs) are an integral part of peripheral tolerance, suppressing immune reactions against self-structures and thus preventing ...

Detection of Inflammasome Activation and Pyroptotic Cell Death in Murine Bone Marrow-derived Macrophages

Inflammasomes are innate immune signaling platforms that are required for the successful control of many pathogenic organisms, but also promote inflammatory and autoinflammatory diseases. Inflammasomes are activated by cytosolic pattern recognition receptors, including members of the NOD-like receptor (NLR) family. These receptors oligomerize upon the detection of microbial or damage-associated stimuli. Subsequent recruitment of the adaptor protein ASC forms a microscopically visible inflammasome complex, which activates caspase-1 through proximity-induced auto-activation. Following the activation, caspase-1 cleaves pro-IL-1&#946; and pro-IL-18, leading to the activation and secretion of these pro-inflammatory cytokines. Caspase-1 also mediates the inflammatory form of cell death termed pyroptosis, which features the loss of membrane integrity and cell lysis. Caspase-1 cleaves gasdermin D, releasing the N-terminal fragment which forms plasma membrane pores, leading to osmotic lysis.
In vitro, the activation of caspase-1 can be determined by labeling bone marrow-derived macrophages with the caspase-1 activity probe FAM-YVAD-FMK and by labeling the cells with antibodies against the adaptor protein ASC. This technique allows the identification of inflammasome formation and caspase-1 activation in individual cells using fluorescence microscopy. Pyroptotic cell death can be detected by measuring the release of cytosolic lactate dehydrogenase into the medium. This procedure is simple, cost effective and performed in a 96-well plate format, allowing adaptation for screening. In this manuscript, we show that activation of the NLRP3 inflammasome by nigericin leads to the co-localization of the adaptor protein ASC and active caspase-1, leading to pyroptosis.

We describe the detection of NLRP3 inflammasome activation on cellular basis using fluorescence microscopy and staining for active caspase-1 and the adaptor, ASC. A lactate dehydrogenase release assay is presented to detect pyroptotic lysis on a population basis. These techniques can be adapted to study many aspects of inflammasome biology.