Name: promoting 3-d aggregation of facs purified thymic epithelial cells with eak 16-ii/eakiih6 self-assembling hydrogel
Uploaded: 2016-06-27T14:00:00
Description: Watch this Scientific Journal Video about Promoting 3-D Aggregation of FACS Purified Thymic Epithelial Cells with EAK 16-II/EAKIIH6 Self-assembling Hydrogel at JoVE.com

This work was supported in part by the National Institutes of Health grants R21 AI113000 (W.S.M) and R01 AI123392 (Y.F.).

All the animals used in the experiments were housed in the animal facility at Allegheny-Singer Research Institute under the protocol reviewed and approved by the Institutional Animal Care and Use Committee of the Allegheny Health Network/Allegheny Singer Research Institute.
1. Digesting the Thymus with Collagenase
<ol>
	<li>Harvest thymus glands.
	<ol>
		<li>Euthanize 3-5 week-old C57BL6/J mice in a carbon dioxide (CO2) chamber to harvest thymus glands. In detail, place the mice i...

<ol>
	<li>Anderson, G., Jenkinson, E. J., Moore, N. C., Owen, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MHC+class+II-positive+epithelium+and+mesenchyme+cells+are+both+required+for+T-cell+development+in+the+thymus.">MHC class II-positive epithelium and mesenchyme cells are both required for T-cell development in the thymus.</a> Nature. 362, 70-73 (1993).</li><li>Fan, Y., 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=Thymus-specific+deletion+of+insulin+induces+autoimmune+diabetes.">Thymus-specific deletion of insulin induces autoimmune diabetes.</a> The EMBO J. 28, 2812-2824 (2009).</li><li>Mohtashami, M., Zuniga-Pflucker, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+architecture+of+the+thymus+is+required+to+maintain+delta-like+expression+necessary+for+inducing+T+cell+development.">Three-dimensional architecture of the thymus is required to maintain delta-like expression necessary for inducing T cell development.</a> J Immunol. 176, 730-734 (2006).</li><li>Pinto, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+organotypic+coculture+model+supporting+proliferation+and+differentiation+of+medullary+thymic+epithelial+cells+and+promiscuous+gene+expression.">An organotypic coculture model supporting proliferation and differentiation of medullary thymic epithelial cells and promiscuous gene expression.</a> J Immunol. 190, 1085-1093 (2013).</li><li>Fung, S. Y., Yang, H., Chen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+colloidal+suspension+of+hydrophobic+compounds+with+an+amphiphilic+self-assembling+peptide.">Formation of colloidal suspension of hydrophobic compounds with an amphiphilic self-assembling peptide.</a> Colloids Surf B Biointerfaces. 55, 200-211 (2007).</li><li>Jun, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-assembly+of+the+ionic+peptide+EAK16:+the+effect+of+charge+distributions+on+self-assembly.">Self-assembly of the ionic peptide EAK16: the effect of charge distributions on self-assembly.</a> Biophys J. 87, 1249-1259 (2004).</li><li>Saunders, M. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+fluorogen+activating+proteins+into+self-assembling+materials.">Engineering fluorogen activating proteins into self-assembling materials.</a> Bioconjug Chem. 24, 803-810 (2013).</li><li>Zhang, S., Holmes, T., Lockshin, C., Rich, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spontaneous+assembly+of+a+self-complementary+oligopeptide+to+form+a+stable+macroscopic+membrane.">Spontaneous assembly of a self-complementary oligopeptide to form a stable macroscopic membrane.</a> Proc of the Natl Acad Sci U S A. 90, 3334-3338 (1993).</li><li>Wen, Y., 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=Coassembly+of+amphiphilic+peptide+EAK16-II+with+histidinylated+analogues+and+implications+for+functionalization+of+beta-sheet+fibrils+in+vivo.">Coassembly of amphiphilic peptide EAK16-II with histidinylated analogues and implications for functionalization of beta-sheet fibrils in vivo.</a> Biomaterials. 35, 5196-5205 (2014).</li><li>Zheng, Y., 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=A+peptide-based+material+platform+for+displaying+antibodies+to+engage+T+cells.">A peptide-based material platform for displaying antibodies to engage T cells.</a> Biomaterials. 32, 249-257 (2011).</li><li>Tajima, 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=Bioengineering+mini+functional+thymic+units+with+EAK16-II/EAKIIH6+self-assembling+hydrogel.">Bioengineering mini functional thymic units with EAK16-II/EAKIIH6 self-assembling hydrogel.</a> Clin Immunol. 160, 82-89 (2015).</li><li>Fan, Y., 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=Bioengineering+Thymus+Organoids+to+Restore+Thymic+Function+and+Induce+Donor-Specific+Immune+Tolerance+to+Allografts.">Bioengineering Thymus Organoids to Restore Thymic Function and Induce Donor-Specific Immune Tolerance to Allografts.</a> Mol Ther. 23, 1262-1277 (2015).</li><li>Fan, Y., 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=Thymus-specific+deletion+of+insulin+induces+autoimmune+diabetes.">Thymus-specific deletion of insulin induces autoimmune diabetes.</a> The EMBO J. 28, 2812-2824 (2009).</li><li>Fan, Y., 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=Compromised+central+tolerance+of+ICA69+induces+multiple+organ+autoimmunity.">Compromised central tolerance of ICA69 induces multiple organ autoimmunity.</a> J Autoimmun. 53, 10-25 (2014).</li><li>Palumbo, M. O., Levi, D., Chentoufi, A. A., Polychronakos, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+characterization+of+proinsulin-producing+medullary+thymic+epithelial+cell+clones.">Isolation and characterization of proinsulin-producing medullary thymic epithelial cell clones.</a> Diabetes. 55, 2595-2601 (2006).</li><li>Williams, K. 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=Single+cell+analysis+of+complex+thymus+stromal+cell+populations:+rapid+thymic+epithelia+preparation+characterizes+radiation+injury.">Single cell analysis of complex thymus stromal cell populations: rapid thymic epithelia preparation characterizes radiation injury.</a> Clin Transl Sci. 2, 279-285 (2009).</li><li>McLelland, B. T., Gravano, D., Castillo, J., Montoy, S., Manilay, J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhanced+isolation+of+adult+thymic+epithelial+cell+subsets+for+multiparameter+flow+cytometry+and+gene+expression+analysis.">Enhanced isolation of adult thymic epithelial cell subsets for multiparameter flow cytometry and gene expression analysis.</a> J Immunol Methods. 367, 85-94 (2011).</li><li>Seach, N., Wong, K., Hammett, M., Boyd, R. L., Chidgey, A. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purified+enzymes+improve+isolation+and+characterization+of+the+adult+thymic+epithelium.">Purified enzymes improve isolation and characterization of the adult thymic epithelium.</a> J Immunol methods. 385, 23-34 (2012).</li><li>Xing, Y., Hogquist, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation,+identification,+and+purification+of+murine+thymic+epithelial+cells.">Isolation, identification, and purification of murine thymic epithelial cells.</a> J Vis Exp. , e51780 (2014).</li><li>Graham, 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=Separation+of+monocytes+from+whole+human+blood.">Separation of monocytes from whole human blood.</a> ScientificWorldJournal. 2, 1540-1543 (2002).</li><li>Li, X., Donowitz, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fractionation+of+subcellular+membrane+vesicles+of+epithelial+and+nonepithelial+cells+by+OptiPrep+density+gradient+ultracentrifugation.">Fractionation of subcellular membrane vesicles of epithelial and nonepithelial cells by OptiPrep density gradient ultracentrifugation.</a> Methods Mol Biol. 440, 97-110 (2008).</li><li>Mita, 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=Purification+method+using+iodixanol+(OptiPrep)-based+density+gradient+significantly+reduces+cytokine+chemokine+production+from+human+islet+preparations,+leading+to+prolonged+beta-cell+survival+during+pretransplantation+culture.">Purification method using iodixanol (OptiPrep)-based density gradient significantly reduces cytokine chemokine production from human islet preparations, leading to prolonged beta-cell survival during pretransplantation culture.</a> Transplant Proc. 41, 314-315 (2009).</li><li>Anderson, G., Takahama, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thymic+epithelial+cells:+working+class+heroes+for+T+cell+development+and+repertoire+selection.">Thymic epithelial cells: working class heroes for T cell development and repertoire selection.</a> Trends Immunol. 33, 256-263 (2012).</li><li>Kyewski, B., Klein, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+central+role+for+central+tolerance.">A central role for central tolerance.</a> Annu Rev Immunol. 24, 571-606 (2006).</li><li>St-Pierre, C., 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=Transcriptome+sequencing+of+neonatal+thymic+epithelial+cells.">Transcriptome sequencing of neonatal thymic epithelial cells.</a> Sci Rep. 3, 1860 (2013).</li></ol>

While TECs are the predominant population of the thymic stroma and play essential roles for the structure and function of the thymus glands, they represent only about 0.1-0.5% of the total thymic cellularity. They are also fragile cells as high percentages of cell death are occasionally observed following collagenase digestion, i.e., the treatment to dissociate TECs from the extracellular matrix (ECM). Their rarity (~200,000 per mouse thymus) and fragility made it a challenging task to isolate TECs. The recent u...

The thymus is the primary lymphoid organ responsible for the generation of a diverse population of pathogen-reactive, self-tolerant T cells that is essential to the function of the acquired immune system. It is a dynamic organ where developing thymocytes, immigrated from the bone marrow as lymphocyte progenitor cells, migrate through the sponge-like three-dimensional (3-D) matrix of the thymic stroma, undergo lineage-specification and differentiation, and eventually emigrate as mature T-cells. The success of this well programmed process depends largely on the cross-talk between the migrating thymocytes and the residential thymic epithelial cells (TECs), the predominant population of the thymic stroma that are essential for establishing and maintaining the integrity of the thymus microenvironment.
Based on their anatomical location and unique function, TECs can be divided into two subsets: the TECs in the cortex (cTECs) that are responsible for selecting self-MHC (major histocompatibility complex) restricted T-cells (positive selection), and the TECs in the medulla (mTECs) that are essential for eliminating autoreactive T-cells (negative selection) 1,2. Many factors (e.g., aging, infection, irradiation, drug treatments) can cause irreversible damages to the thymic epithelium, resulting in compromised adaptive immunity. Despite numerous attempts, restoring the thymic function has been challenging due to the difficulty to reproduce the thymic microenvironment. Notably, thymic three-dimensional (3-D) configuration is critical to the survival and function of TECs, whereas TECs cultured in a 2-D environment rapidly decrease the expression of genes critical for thymopoiesis 3,4.
EAK16-II (AEAEKAKAEAEAKAK) and its C-terminal histidinylated analogue EAKIIH6 (AEAEKAKAEAEAKAKHHHHHH) are low-molecular weight, amphiphilic oligopeptides that are soluble in deionized water, but undergo gelation to form &#946;-fibrils when exposed to ionic strength higher than 20 mM NaCl (normal salt concentration in human body fluid is 154 mM). This environmental responsive property makes them versatile building blocks to form 3D structures. The His-tag on EAKII-H6 provides a docking mechanism, by which the anti-His IgGs/Fc-binding recombinant protein A/G (&#945;H6:pA/G) complexes can serve as an adaptor to anchor protein drugs and other biomolecules (e.g., antibodies) on the hydrogel composite 5-8.
We have previously demonstrated that fluorescent-labeled IgG molecules anchored on the hydrogel can be retained at the injection site for up to 13 days 9. Furthermore, when the &#945;H6:pA/G adaptors anchored with anti-CD4 IgGs were added to the EAK16-II/EAKIIH6 (EAK) hydrogel, CD4+ T cells were specifically captured 10. Using similar technique, we have recently demonstrated that 3-D aggregation of TECs could be promoted in EAK hydrogel with adaptor complexes carrying TEC-specific anti-EpCAM antibodies (&#945;H6:pA/G:&#945;EpCAM). When transplanted underneath the kidney capsules of nude mice, the TEC clusters embedded in EAK hydrogel can effectively support the development of functional T cells in vivo11,12.
Here we illustrate our method to quickly and effectively purify TECs with fluorescence-activated cell sorting (FACS) and generate 3-D TEC aggregates with the EAK hydrogel system.

<table border="0" cellpadding="0" cellspacing="0" width="722">
	<tbody>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">1. TEC Isolation</td>
			<td style="width:175px;"></td>
			<td style="width:111px;"></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">70% Ethanol</td>
			<td>Decon Laboratories</td>
			<td>2701(1 Gallon)</td>
			<td style="width:223px;">Ethanol 200 Proof, deionized water</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Dissecting scissors, straight</td>
			<td>Fine Science Tools, Inc.</td>
			<td>91460-11</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Graefe forceps, straight</td>
			<td>Fine Science Tools, Inc.</td>
			<td>11053-10</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Graefe forceps, curved</td>
			<td>Fine Science Tools, Inc.</td>
			<td>11052-10</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:216px;">Washing solution</td>
			<td></td>
			<td></td>
			<td style="width:223px;">1X PBS, 0.1% BSA, 2mM EDTA</td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;width:216px;">1x PBS (Phosphate buffered saline)</td>
			<td>Gibco</td>
			<td>10010-023</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">BSA (Bovine serum albumin)</td>
			<td>Sigma</td>
			<td>A1470-100G</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="46">
			<td height="46" style="height:47px;width:216px;">EDTA (ethylenediaminetetraacetic acid)</td>
			<td>Invitrogen</td>
			<td>15575-038</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="66">
			<td height="66" style="height:67px;width:216px;">Digestion solution</td>
			<td></td>
			<td></td>
			<td style="width:223px;">9 mL RPMI-1640, 0.025 mg/mL Liberase TM Research grade, 10 mM HEPES, 0.2 mg/mL DNaseI</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">RPMI-1640</td>
			<td>Gibco</td>
			<td>11879-020</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Liberase TM Research Grade</td>
			<td>Roche</td>
			<td>05 401 127 001</td>
			<td style="width:223px;">referred as &#34;purified collagenase&#34;</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">1M HEPES</td>
			<td>Lonza</td>
			<td>17-737E</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Dnase I</td>
			<td>Roche</td>
			<td>10 104 159 001</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">50mL Centrifuge tube</td>
			<td>Corning</td>
			<td>430290</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">60mm tissue culture dish</td>
			<td>Falcon</td>
			<td>353002</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:27px;width:216px;">1/2cc U-100 Insulin syringe 28G1/2</td>
			<td>Becton Dickinson</td>
			<td>329461</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;width:216px;">5mL Polystyrene round-bottom tube</td>
			<td>Falcon</td>
			<td>352058</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="62">
			<td height="62" style="height:63px;width:216px;">5ml glass pipet</td>
			<td>Fisher Healthcare</td>
			<td>13-678-27E</td>
			<td style="width:223px;">Use for rinsing the thymic fragments. Thymic fragments tend to stick to the wall with plastic pipets.</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">MACSmix tube rotator</td>
			<td>Miltenyi</td>
			<td>130-090-753</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">100um Cell strainer</td>
			<td>Falcon</td>
			<td>352360</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Density gradient medium: OptiPrep</td>
			<td>Axis-Shield</td>
			<td></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Name</td>
			<td style="width:175px;">Company</td>
			<td style="width:111px;">Catalog Number</td>
			<td style="width:223px;">Comments</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">2. Cell sorting</td>
			<td></td>
			<td></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="38">
			<td height="38" style="height:39px;width:216px;">5mL Polypropylene round-bottom tube</td>
			<td>Falcon</td>
			<td>352063</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Anti-mouse CD16/CD32 (Fc Block)</td>
			<td>BD Biosciences</td>
			<td>553142</td>
			<td style="width:223px;">Use as undiluted, 2uL per sample</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Anti-mouse CD45-PercpCy5.5</td>
			<td>eBioscience</td>
			<td>45-0451-80</td>
			<td style="width:223px;">Use at 1:150, 10uL per sample</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Anti-mouse CD326 (EpCAM)-PE</td>
			<td>eBioscience</td>
			<td>12-5791-82</td>
			<td style="width:223px;">Use at 1:100, 10uL per sample</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">BD Influx</td>
			<td>BD Biosciences</td>
			<td></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Single cell analysis software</td>
			<td>FlowJo</td>
			<td></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Name</td>
			<td style="width:175px;">Company</td>
			<td style="width:111px;">Catalog Number</td>
			<td style="width:223px;">Comments</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">2. EAK gel assembly</td>
			<td></td>
			<td></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Anti-His-Tag</td>
			<td>AnaSpec</td>
			<td>29673</td>
			<td style="width:223px;">&#34;anti-His-Tag IgG&#34;</td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;width:216px;">Purified anti-mouse CD326 (EpCAM)</td>
			<td>BioLegend</td>
			<td>118202</td>
			<td style="width:223px;">&#34;anti-EpCAM IgG&#34;</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Recombinant protein A/G</td>
			<td>Pierce Biotechnology</td>
			<td></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="50">
			<td height="50" style="height:51px;width:216px;">1.5mL Safe-Lock Tubes, Biopur, Sterile</td>
			<td>Fisher Healthcare</td>
			<td>05-402-24B</td>
			<td style="width:223px;">referred as &#34;1.5mL microcentrifuge tube&#34;&#160;</td>
		</tr>
		<tr height="51">
			<td height="51" style="height:51px;width:216px;">96-well, Tissue culture plate, Round-bottom with low evaporation lid</td>
			<td>BD Falcon</td>
			<td>353917</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Rocking platform: Nutator Mixer no.1105</td>
			<td>BD Clay Adams</td>
			<td></td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">10% sucrose</td>
			<td>Sigma</td>
			<td>S0389</td>
			<td style="width:223px;">Prepare with sterile distilled water</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:216px;">EAK16-II (AcNH-AEAEAKAKAEAEAKAK-CONH2)</td>
			<td>American Peptide Company&#160;</td>
			<td></td>
			<td style="width:223px;">custom synthesized, 10mg/mL</td>
		</tr>
		<tr height="58">
			<td height="58" style="height:59px;width:216px;">EAKIIH6 (AcNH-AEAEAKAKAEAEAKAKHHHHHH-CONH2)</td>
			<td>American Peptide Company&#160;</td>
			<td></td>
			<td style="width:223px;">custom synthesized, 7.5mg/mL</td>
		</tr>
		<tr height="76">
			<td height="76" style="height:76px;width:216px;">Complete medium</td>
			<td></td>
			<td></td>
			<td style="width:223px;">RPMI-1640, 10% FBS, 1% Pen/Strep, 1% L-glutamine, 1% NEAA, 5mM HEPES, 50uM 2-Mercaptoethanol</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">RPMI-1640&#160;</td>
			<td>Gibco</td>
			<td>11879-020</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">FBS (Fetal Bovine Serum)</td>
			<td>Atlanta Biologicals</td>
			<td>S11150</td>
			<td style="width:223px;">Heat inactivated before use</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">Pen/Strep</td>
			<td>Gibco</td>
			<td>15140-122</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">L-glutamine 200mM (100x)</td>
			<td>Gibco</td>
			<td>25030-081</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:43px;width:216px;">NEAA (non-essential amino acid) 100x</td>
			<td>Gibco</td>
			<td>11140-050</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:216px;">1M HEPES</td>
			<td>BioWhittaker</td>
			<td>17-737E</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:216px;">2-Mercaptoethanol (100X)</td>
			<td>Millipore</td>
			<td>ES-007-E</td>
			<td style="width:223px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Platform shaker: The Belly Dancer</td>
			<td>Stovall Life Sciences Inc.</td>
			<td>model: USBDbo</td>
			<td style="width:223px;"></td>
		</tr>
	</tbody>
</table>

promoting 3-d aggregation of facs purified thymic epithelial cells with eak 16-ii/eakiih6 self-assembling hydrogel

Thymus involution, associated with aging or pathological insults, results in diminished output of mature T-cells. Restoring the function of a failing thymus is crucial to maintain effective T cell-mediated acquired immune response against invading pathogens. However, thymus regeneration and revitalization proved to be challenging, largely due to the difficulties of reproducing the unique 3D microenvironment of the thymic stroma that is critical for the survival and function of thymic epithelial cells (TECs). We developed a novel hydrogel system to promote the formation of TEC aggregates, based on the self-assembling property of the amphiphilic EAK16-II oligopeptides and its histidinylated analogue EAKIIH6. TECs were enriched from isolated thymic cells with density-gradient, sorted with fluorescence-activated cell sorting (FACS), and labeled with anti-epithelial cell adhesion molecule (EpCAM) antibodies that were anchored, together with anti-His IgGs, on the protein A/G adaptor complexes. Formation of cell aggregates was promoted by incubating TECs with EAKIIH6 and EAK16-II oligopeptides, and then by increasing the ionic concentration of the medium to initiate gelation. TEC aggregates embedded in EAK hydrogel can effectively promote the development of functional T cells in vivo when transplanted into the athymic nude mice.

To examine the effectiveness of using the density gradient separation protocol to enrich the CD45- stromal cells, cells harvested from both the interface and the precipitated lymphocyte pellets were stained with anti-CD45 and anti-EpCAM antibodies. Both anti-Ulex Europaeus Agglutinin 1 (UEA1) and anti-MHC Class II antibodies were also included in the staining cocktail to further identify the cTEC and mTEC subsets. As shown in Figure 1, we were able to routinely achieve cl...

Watch this Scientific Journal Video about Promoting 3-D Aggregation of FACS Purified Thymic Epithelial Cells with EAK 16-II/EAKIIH6 Self-assembling Hydrogel at JoVE.com

Promoting 3-D Aggregation of FACS Purified Thymic Epithelial Cells with EAK 16-II/EAKIIH6 Self-assembling Hydrogel

This video demonstrates a protocol to enrich thymic epithelial cells (TECs) with density gradient for FACS isolation. It also shows the use of EAK16-II/EAKIIH6 peptides to promote the TEC aggregate formation. The microenvironments of EAK16-II/EAKIIH6 hydrogel provide the 3-D configuration necessary to maintain the survival and function of the TECs.

Thymus involution, associated with aging or pathological insults, results in diminished output of mature T-cells. Restoring the function of a failing ...

Research

JoVE Journal

Immunology and Infection

Induction and Assessment of Class Switch Recombination in Purified Murine B Cells

Humoral immunity is the branch of the immune system maintained by B cells and mediated through the secretion of antibodies. Upon B cell activation, the ...

In Vitro Assay of Bacterial Adhesion onto Mammalian Epithelial Cells

In Vitro Assay of Bacterial Adhesion onto Mammalian Epithelial Cells

To cause infections, bacteria must colonize their host. Bacterial pathogens express various molecules or structures able to promote attachment to host ...

Application of a Mouse Ligated Peyer&#x2019;s Patch Intestinal Loop Assay to Evaluate Bacterial Uptake by M cells

Application of a Mouse Ligated PeyerÃƒÂ¢Ã¢â€šÂ¬Ã¢â€žÂ¢s Patch Intestinal Loop Assay to Evaluate Bacterial Uptake by M cells

The inside of our gut is inhabited with enormous number of commensal bacteria. The mucosal surface of the gastrointestinal tract is continuously exposed ...

Examination of Thymic Positive and Negative Selection by Flow Cytometry

A healthy immune system requires that T cells respond to foreign  antigens while remaining tolerant to self-antigens. Random rearrangement of the  T cell ...

Identifying DNA Mutations in Purified Hematopoietic Stem/Progenitor Cells

In recent years, it has become apparent that genomic instability is tightly related to many developmental disorders, cancers, and aging. Given that stem ...

Isolation of Myeloid Dendritic Cells and Epithelial Cells from Human Thymus

In this protocol we provide a method to isolate dendritic cells (DC) and epithelial cells (TEC) from the human thymus. DC and TEC are the major antigen ...

Isolation, Identification, and Purification of Murine Thymic Epithelial Cells

The thymus is a vital organ for T lymphocyte development. Of thymic stromal cells, thymic epithelial cells (TECs) are particularly crucial at multiple ...

Isolation and Transplantation of Different Aged Murine Thymic Grafts.

The mechanisms that regulate the efficacy of thymic selection remain ill-defined. The method presented here allows in vivo analyses of the development and ...

Preparation and Applications of Organotypic Thymic Slice Cultures

Thymic selection proceeds in a unique and highly organized thymic microenvironment resulting in the generation of a functional, self-tolerant T cell ...