This work was supported in part by research funding from the Elisabeth Glaser Pediatric AIDS Foundation (Pediatric HIV Vaccine Program Award MV-00-9-900-1429-0-00 to MMA), MGH/ECOR (Physician Scientist Development Award to MMA), NIH NIAID (KO8219 AI074405 and AI074405-03S1 to MMA), and the Harvard University Center for AIDS Research (CFAR), an NIH funded program (P30 AI060354) which is supported by the following NIH Co-Funding and Participating Institutes and Centers: NIAID, NCI, NICHD, NHLBI, NIDA, NIMH, NIA, FIC, and OAR. These studies were furthermore supported by the Bill &amp; Melinda Gates Foundation and the Terry and Susan Ragon Foundation.

1. Regulatory T cell isolation from HIV-1 Positive Blood
<ol>
	<li>Carefully transfer blood, collected in ACD tubes, into a 50 ml conical tube for a final volume of 15 ml blood per tube.</li>
	<li>Add 25 &mu;l/ml of blood of RosetteSep Human CD4+ T Cell Enrichment Cocktail, mix carefully and incubate 20 min at room temperature.</li>
	<li>Add 15 ml of PBS/2% FBS to the blood and mix carefully. Layer the diluted blood sample on top of 15 ml of Histopaque at room temperature in a 50 ml conical tube. Spin the conical tube for 20 min at 1,200 x g with a slow start and no brakes.</li>
	<li>Transfer the CD4+ T cell enriched PBMC layer in a new 50 ml conical tube, wash the cells by adding PBS/2% FBS and spin them down for 10 min at 1,200 x g. Then count the cells, wash again and resuspend the cells at about 20 x 106/200 &mu;l.</li>
	<li>Add the following antibodies (concentration): 
	anti-CD3-Phycoerythrin-Cyanine 7 (PE-Cy7) (1/100) 
	anti-CD4-Fluorescein Isothiocyanate (FITC) (1/40) 
	anti-CD25-Allophycocyanin (APC) (1/40) 
	anti-CD127-Phycoerythrin (PE) (1/20) 
	Incubate 30 min in the dark at 4 &deg;C</li>
	<li>Wash the cells with PBS/2% FBS. Resuspend the cells at 20 x 106/ml in PBS/2% FBS and filter them on a 35 &mu;m nylon mesh.</li>
	<li>Using a FACS Aria cell sorter equipped for handling biohazardous material, sort the CD3+CD4+CD25+CD127low Treg in X-VIVO 15 media (see gating strategy in Figure 1). Conventional T cells (CD3+CD4+CD25-CD127+) can be isolated and expanded as negative controls.</li>
</ol>
2. Cell Culture
<ol>
	<li>After isolation, wash the Treg with X-VIVO 15 media.</li>
	<li>Resuspend the cells at 250 x 103/ml in X-VIVO 15 media complemented with 10% Human Serum and Penicillin-Streptomycin (50 U/ml).</li>
	<li>Wash Human T-Activator CD3/CD28 beads according to manufacturer's protocol. Add beads to isolated Tregs at a ratio of 1:1 bead per cell.</li>
	<li>After two days of culture, double the media volume and add IL-2 (300 U/ml).</li>
	<li>Culture the Tregs for 2 weeks. Change media (X-VIVO 15/Human serum/P/S/IL-2) at days 5, 7, 9, 12. Add beads at a 1:1 ratio at day 9. When changing media, keep cells at 250 x 103/ml.</li>
</ol>
3. Phenotyping
At the end of the expansion culture, expanded CD3+CD4+CD25+CD127low Treg can be phenotyped by flow cytometry and compared to expanded CD3+CD4+CD25-CD127+ conventional T cells as a control.
<ol>
	<li>Harvest expanded Tregs/Tconvs and wash them in PBS. Label dead cells using the LIVE/DEAD Fixable Violet Dead Cell Stain Kit according to manufacturer's protocol. Wash the cells in PBS/2% FBS.</li>
	<li>Add the following antibodies (concentration): 
	anti-CD3-PECy7 (1/100) 
	anti-CD4-Qdot-655 (1/200) 
	anti-CD25-PECy5 (1/100) 
	Incubate 30 min in the dark at 4 &deg;C</li>
	<li>Wash the cells and perform the intracellular staining using the Foxp3/ Transcription Factor Staining Buffer Set according to manufacturer's protocol and the following antibodies: 
	anti-FOXP3-PE (1/50) 
	anti-HELIOS-FITC (1/40) 
	anti-CTLA4-APC (1/20) 
	Acquire the data on a flow cytometer.</li>
</ol>
4. Suppression Assay
At the end of the expansion culture, the suppressive function i.e. the capacity of the expanded Treg isolated from HIV-1 positive individuals to suppress the proliferation of activated T cells can be assessed in vitro.
<ol>
	<li>Thaw autologous cryopreserved ex vivo PBMCs. Leave them for about 3 hr in a 37 &deg;C incubator in RPMI 1640 medium containing penicillin/streptomycin, L-glutamine, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer (=R+ media), and 10% FBS (=R10 media).</li>
	<li>Label the dead cells using the LIVE/DEAD Fixable Violet Dead Cell Stain Kit according to the manufacturer's protocol. Wash the cells in PBS/2% FBS.</li>
	<li>Incubate the cells with anti-CD3-PECy7 for 30 min in the dark at 4 &deg;C. Wash the cells with PBS/2% FBS. Resuspend the cells in PBS/2% FBS and filter them on a 35 &mu;m nylon mesh.</li>
	<li>Using a FACS Aria cell sorter equipped for handling biohazardous material, sort the viable CD3+ T cells in R10 media.</li>
	<li>Label the T cells with a cell tracing reagent such as CellTrace Violet or Vybrant CFDA SE Cell Tracer at 5 &mu;M diluted in PBS for 7 min at 37 &deg;C according to the manufacturer's protocol. Resuspend cells in R+ media supplemented with 10% human serum (=hR10 media) at 1 x 106/ml.</li>
	<li>Harvest the expanded Tregs, resuspend the cells at 0.5 x 106/ml in hR10 and prepare dilutions at 0.25 x 106/ml and 0.125 x 106/ml.</li>
	<li>Prepare anti-CD2/anti-CD3/anti-CD28 microbeads according to the manufacturer's protocol, resuspend the microbeads at 0.75 x 106/ml and prepare dilutions at 0.625, 0.562, 0.5 x 106/ml in hR10 media.</li>
	<li>In a 96 wells round bottom plate, transfer cells and beads according to the following plan:</li>
</ol>
<table border="1">
	<tbody>
		<tr>
			<td>T cells:Treg ratio</td>
			<td>1:0</td>
			<td>1:1/2</td>
			<td>1:1/4</td>
			<td>1:1/8</td>
		</tr>
		<tr>
			<td>T cells (50 &mu;l)</td>
			<td>1 x 106/ml</td>
			<td>1 x 106/ml</td>
			<td>1 x 106/ml</td>
			<td>1 x 106/ml</td>
		</tr>
		<tr>
			<td>Tregs (50 &mu;l)</td>
			<td>no</td>
			<td>0.5 x 106/ml</td>
			<td>0.25 x 106/ml</td>
			<td>0.125 x 106/ml</td>
		</tr>
		<tr>
			<td>Beads (100 &mu;l)</td>
			<td>0.5 x 106/ml</td>
			<td>0.75 x 106/ml</td>
			<td>0.625 x 106/ml</td>
			<td>0.562 x 106/ml</td>
		</tr>
		<tr>
			<td>hR10 (50 &mu;l)</td>
			<td>yes</td>
			<td>no</td>
			<td>no</td>
			<td>no</td>
		</tr>
		<tr>
			<td>i.e.</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>T cells</td>
			<td>50 x 103</td>
			<td>50 x 103</td>
			<td>50 x 103</td>
			<td>50 x 103</td>
		</tr>
		<tr>
			<td>Tregs</td>
			<td>0</td>
			<td>25 x 103</td>
			<td>12.5 x 103</td>
			<td>6.25 x 103</td>
		</tr>
		<tr>
			<td>Beads</td>
			<td>50 x 103</td>
			<td>75 x 103</td>
			<td>62.5 x 103</td>
			<td>56.25 x 103</td>
		</tr>
	</tbody>
</table>
<ol start="9">
	<li>After 4 days of culture, wash the cells and incubate them for 30 min at 4 &deg;C with the following antibodies: 
	anti-CD3-PECy7 (1/100) 
	anti-CD4-APC (1/100) 
	anti-CD8-AF700 (1/100)</li>
</ol>
Acquire the data on a flow cytometer. Use the FlowJo proliferation platform to calculate the percentage of divided cells.

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The authors declare that they have no competing financial interests.

Using the protocol described above, Tregs can be successfully isolated and expanded from HIV-1-infected individuals in vitro. Expanded Tregs express high levels of FOXP3, CTLA4 and HELIOS, are highly suppressive and display a highly demethylated Treg-Specific Demethylation Region (TSDR) locus of the FOXP3 gene (data not shown) 15, suggesting true origin from the regulatory T cell lineage, as opposed to activation-induced transient FOXP3 upregulation. Deep sequencing demonstrated that the TCR repertoir...

拥有超过3400万个人生活与艾滋病毒/艾滋病在世界范围，估计有250万人新感染在2011年，需要一个有效的HIV疫苗，以遏制全球艾滋病疫情仍然是最重要的。然而，尽管深入研究三十年的努力，已导致HIV-1疫苗的有效性试验只有适度保护1-3保护性免疫的相关性仍然知之甚少。阐明保护所需的免疫反应的性质是必不可少的一种有效的HIV-1的针对HIV-1感染的疫苗和免疫治疗策略的策略设计。 天然的CD4 +调节性T细胞（Treg细胞）通过控制过度的免疫激活，从而限制了免疫介导的组织损伤的免疫细胞稳态的维持是至关重要的。然而，他们也可以对病原体的抑制免疫反应，并防止其间隙。巨蟹座和HEPAtitis疫苗的研究表明，调节性T细胞活性的降低可以提高疫苗的反应和抗原特异性的抗病毒4-7。然而，调节性T细胞在HIV-1感染的背景下，确切的影响还不完全清楚。调节性T细胞减少8活化的T细胞和病毒复制的可能影响免疫激活9。他们还抑制HIV-1的特异性免疫反应，这可能会产生负面的结果病情恶化10,11。因此，能够调节的调节性T细胞活性的HIV-1疫苗，以增强疗效之前，重要的是进一步深入了解这种疾病的上下文中它们的功能。 人CD4 +调节性T细胞是一种相对稀缺的细胞群体，占约5％的CD4 + T细胞的外周血中，和他们的绝对数量进一步减少与艾滋病毒相关的CD4 + T细胞耗竭12 &lt;/ SUP&gt;。电流检测，以评估调节性T细胞的功能，如T细胞增殖实验与调节性T细胞共培养，使用比较大的手机号码12。因此，表征个人与先进的功能和特异性的调节性T细胞在HIV-1疾病已具有挑战性的，尽管他们的艾滋病毒发病机制中的重要性。 从HIV-1患者调节性T细胞体外分离和扩展，可以代表一个解决方案来克服这些限制。在这里，我们介绍一个简单而强大的协议扩大功能的调节性T细胞的HIV-1 感染者体外来自我们进一步解释了表型他们和测试使用流式细胞仪检测其抑制功能。我们相信，这项协议将Tregs的便利和帮助了解自己的角色在HIV-1疾病的进展。

<table border="1">
	<tbody>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>Reagents</td>
		</tr>
		<tr>
			<td>RosetteSep Human CD4+ T Cell Enrichment Cocktail</td>
			<td>Stemcells technologies</td>
			<td>15062</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Sigma</td>
			<td>D8537</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>Sigma</td>
			<td>F4135</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Histopaque</td>
			<td>Sigma</td>
			<td>H8889</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD3-PECy7</td>
			<td>BD Pharmingen</td>
			<td>557851</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD4-FITC</td>
			<td>eBioscience</td>
			<td>11-0049-42</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD25-APC</td>
			<td>eBioscience</td>
			<td>17-0259-42</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD127-PE</td>
			<td>BD Pharmingen</td>
			<td>557938</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Round-Bottom tube with 35 &mu;m a nylon mesh</td>
			<td>BD Falcon</td>
			<td>352235</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>X-VIVO 15</td>
			<td>Lonza</td>
			<td>04-418Q</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin</td>
			<td>Mediatech</td>
			<td>30-001-Cl</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Human Serum</td>
			<td>Gemini Bio-Products</td>
			<td>100-512</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Human T-activator CD3/CD28</td>
			<td>Life Technologies</td>
			<td>111.31D</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>IL-2</td>
			<td>NIH Aids Research &amp; Reference Reagent Program</td>
			<td>136</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>LIVE/DEAD Fixable Violet Dead Cell Stain Kit</td>
			<td>Life technologies</td>
			<td>L34955</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD4-qdot-655</td>
			<td>Life Technologies</td>
			<td>Q10007</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD25-PECy5</td>
			<td>eBiosciences</td>
			<td>15-0259-42</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Foxp3 / Transcription Factor Staining Buffer Set</td>
			<td>eBiosciences</td>
			<td>00-5523-00</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-FOXP3-PE</td>
			<td>eBiosciences</td>
			<td>12-4776-42</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-HELIOS-FITC</td>
			<td>Biolegend</td>
			<td>137204</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CTLA4-APC</td>
			<td>BD Pharmingen</td>
			<td>555855</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>CellTrace Violet Cell Proliferation Kit</td>
			<td>Life Technologies</td>
			<td>C34557</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Vybrant CFDA SE Cell Tracer Kit</td>
			<td>Life Technologies</td>
			<td>V12883</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Mediatech</td>
			<td>25-060-Cl</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Treg Suppression inspector</td>
			<td>Miltenyi Biotec</td>
			<td>130-092-909</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD4-APC</td>
			<td>BD Pharmingen</td>
			<td>340443</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-CD8-AF700</td>
			<td>BD Pharmingen</td>
			<td>557945</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>RPMI 1640</td>
			<td>Sigma</td>
			<td>R0883</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Glutamine</td>
			<td>Mediatech</td>
			<td>25-002-Cl</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>Materials</td>
		</tr>
		<tr>
			<td>BD Vacutainer Blood Collection Tube w/ ACID CITRATE DEXTROSE (ACD)</td>
			<td>Becton, Dickinson and Company (BD)</td>
			<td>364606</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>FACSAria IIu Cell Sorter</td>
			<td>BD Biosciences</td>
			<td>-</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>LSR II Flow Cytometer</td>
			<td>BD Biosciences</td>
			<td>-</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>FlowJo</td>
			<td>Tree Star</td>
			<td>v887</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

new tools to expand regulatory t cells from hiv-1-infected individuals

CD4 +调节性T细胞（Treg细胞）是强有力的免疫调节剂，在人体免疫稳态中发挥重要作用。导致可测量的增加，在癌症和感染病原体的疫苗设置的抗原特异性T细胞应答的调节性T细胞的耗竭。然而，它们的作用在HIV-1免疫发病机制仍存在争议，因为它们既可以起到抑制有害的HIV-1相关的免疫激活，从而减慢HIV-1疾病的进展或者抑制HIV-1的特异性免疫力，从而促进病毒蔓延。理解和调节Treg细胞功能的背景下，HIV-1可能导致免疫治疗或艾滋病毒疫苗的潜在的新战略。然而，重要的开放问题依然存在的背景下，HIV-1的感染，这需要仔细研究自己的角色。 占大约5％的人类CD4 + T细胞在外周血中，研究调节性T细胞的人口已被证明是困难的，第ESpecially在HIV-1感染个体的HIV-1相关的CD4 T细胞和调节性T细胞耗竭与发生。调节性T细胞在个体与先进的HIV-1病或组织样品，其中只有非常小的生物样品可以通过以下方式获得，因此极具挑战性的表征。我们提出了一个技术解决方案来克服这些限制，使用调节性T细胞的分离和扩增HIV-1阳性的个体。 在这里，我们介绍一个简单而可靠的方法，成功地扩大调节性T细胞体外 HIV-1 感染者隔离。流的排序条件CD3 + CD4 + CD25 + CD127 低调节性T细胞刺激与anti-CD3/anti-CD28包被的磁珠，并在IL-2存在下培养。扩大调节性T细胞表达高水平的FOXP3，CTLA4 HELIOS相比传统的T细胞被证明是高度抑制。更容易获得大量的调节性T细胞，将使研究人员能够解决我的mportant问题，他们在HIV-1免疫病理的作用。我们认为，回答这些问题可能​​为一个有效的HIV-1疫苗的发展提供有益的启示。

The expression of interleukin 2 receptor (CD25) and the interleukin 7 receptor (CD127) have been described as reliable surface markers to identify functional Treg populations 13 and have been shown to correlate with CD4+CD25+FOXP3+ Tregs 9,12. Figure 1 represents the gating strategy used to flow-sort single CD3+CD4+CD25+CD127low Tregs from PBMC isolated from an HIV-1-positive individual. The CD25/CD127 anti...

Watch this Scientific Journal Video about New Tools to Expand Regulatory T Cells from HIV-1-infected Individuals at JoVE.com

New Tools to Expand Regulatory T Cells from HIV-1-infected Individuals

CD4+ Regulatory T cells are potent immune-modulators and serve important functions in immune homeostasis. The paucity of these cells in peripheral blood makes functional studies challenging, specifically in the context of HIV-1-infection. We here describe a method to isolate and expand functional CD4+ Tregs from peripheral blood from HIV-1-infected individuals.

新工具展开调节性T细胞的HIV-1感染的个体

CD4+ Regulatory T cells (Tregs) are potent immune modulators and serve an important function in human immune homeostasis. Depletion of Tregs has led to ...

new-tools-to-expand-regulatory-t-cells-from-hiv-1-infected-individuals

Research

JoVE Journal

Immunology and Infection

11.1K 次观看.  Ragon Institute of MGH, MIT, and Harvard. CD4+ Regulatory T cells are potent immune-modulators and serve important functions in immune homeostasis. The paucity of these cells in peripheral blood makes functional studies challenging, specifically in the context of HIV-1-infection. We here describe a method to isolate and expand functional CD4+ Tregs from peripheral blood from HIV-1-infected individuals.

视频: New Tools to Expand Regulatory T Cells from HIV-1-infected Individuals

Generation of Induced Regulatory T Cells from Primary Human Na&iuml;ve and Memory T Cells

The development and maintenance of immunosuppressive CD4+ regulatory T cells (Tregs) contribute to the peripheral tolerance needed to remain in immunologic homeostasis with the vast amount of self and commensal antigens in and on the human body. Perturbations in the balance between Tregs and inflammatory conventional T cells can result in immunopathology or cancer. Although therapeutic injection of Tregs has been shown to be efficacious in murine models of colitis1 , type I diabetes2 , rheumatoid arthritis and graft versus host disease,4 several fundamental differences in human versus mouse Treg biology5 has thus far precluded clinical use. The lack of sufficient number, purity, stability and homing specificity of therapeutic Tregs necessitated a dynamic platform of human Treg development on which to optimize conditions for their ex vivo expansion6.
Here we describe a method for the differentiation of induced Tregs (iTregs) from a single human peripheral blood donor which can be broken down into four stages: isolation of peripheral blood mononuclear cells, magnetic selection of CD4+ T cells, in vitro cell culture and fluorescence activated cell sorting (FACS) of T cell subsets. Since the Treg signature transcription factor forkhead box P3 (FoxP3) is an activation-induced transcription factor in humans7 and no other unique marker exists, a combinatorial panel of markers must be used to identify T cells with suppressor activity. After six days in culture, cells in our system can be demarcated into na&iuml;ve T cells, memory T cells or iTregs based on their relative expression of CD25 and CD45RA. As memory and na&iuml;ve T cells have different reported polarization requirements and plasticities8 , pre-sorting of the initial T cell population into CD45RA+ and CD45RO+ subsets can be used to examine these discrepancies. Consistent with others, our CD25HiCD45RA- iTregs express high levels of FoxP39 , GITR and CTLA-411 and low levels of CD12712 . Following FACS of each population, resultant cells can be used in a suppressor assay which evaluates the relative ability to retard the proliferation of carboxyfluorescein succinimidyl ester (CFSE)-labeled autologous T cells.

Generation of Induced Regulatory T Cells from Primary Human Na&amp;#239;ve and Memory T Cells

We describe a method for generating regulatory, memory and na&#239;ve T cells from a single human blood donor. Polarized Tregs can be then compared to other subsets in a variety of genetic and functional applications with genetic homogeneity, including a suppression assay also detailed here.

从初级人类的幼稚和记忆T细胞的诱导调节性T细胞的生成

The development and maintenance of immunosuppressive CD4+ regulatory T cells (Tregs) contribute to the peripheral tolerance needed to remain in ...

科研

免疫与感染

Isolation of Double Negative &#945;&#946; T Cells from the Kidney

There is currently no standard protocol for the isolation of DN T cells from the non-lymphoid tissues despite their increasingly reported involvement in various immune responses. DN T cells are a unique immune cell type that has been implicated in regulating immune and autoimmune responses and tolerance to allotransplants1-6. DN T cells are, however, rare in peripheral blood and secondary lymphoid organs (spleen and lymph nodes), but are major residents of the normal kidney. Very little is known about their pathophysiologic function7 due to their paucity in the periphery. We recently described a comprehensive phenotypic and functional analysis of this population in the kidney8 in steady state and during ischemia reperfusion injury. Analysis of DN T cell function will be greatly enhanced by developing a protocol for their isolation from the kidney.
Here, we describe a novel protocol that allows isolation of highly pure ab CD4+ CD8+ T cells and DN T cells from the murine kidney. Briefly, we digest kidney tissue using collagenase and isolate kidney mononuclear cells (KMNC) by density gradient. This is followed by two steps to enrich hematopoietic T cells from 3% to 70% from KMNC. The first step consists of a positive selection of hematopoietic cells using a CD45+ isolation kit. In the second step, DN T cells are negatively isolated by removal of non-desired cells using CD4, CD8, and MHC class II monoclonal antibodies and CD1d &#945;-galcer tetramer. This strategy leads to a population of more than 90% pure DN T cells. Surface staining with the above mentioned antibodies followed by FACs analysis is used to confirm purity.

Isolation of Double Negative &amp;#945;&amp;#946; T Cells from the Kidney

DNabT cells are rare among peripheral T cells; however, they are abundant in certain non-lymphoid tissues. Difficulty of isolating DN T cells from non-lymphoid tissue hinders their functional analysis despite increasing recognized pathophysiologic significance. We describe a novel protocol for isolation of highly purified DN T cells from murine kidney.

从肾脏双重否定αβ性T细胞的分离

There is currently no standard protocol for the isolation of DN T cells from the non-lymphoid tissues despite their increasingly reported involvement in ...

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.

评估的HIV-1感染的CD4的先天传感<sup&gt; +</sup&gt;性T细胞浆细胞样树突细胞使用<em&gt;体外</em&gt;共培养体系。

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

Derivation of T Cells In Vitro from Mouse Embryonic Stem Cells

The OP9/OP9-DL1 co-culture system has become a well-established method for deriving differentiated blood cell types from embryonic and hematopoietic progenitors of both mouse and human origin. It is now used to address a growing variety of complex genetic, cellular and molecular questions related to hematopoiesis, and is at the cutting edge of efforts to translate these basic findings to therapeutic applications. The procedures are straightforward and routinely yield robust results. However, achieving successful hematopoietic differentiation in vitro requires special attention to the details of reagent and cell culture maintenance. Furthermore, the protocol features technique sensitive steps that, while not difficult, take care and practice to master. Here we focus on the procedures for differentiation of T lymphocytes from mouse embryonic stem cells (mESC). We provide a detailed protocol with discussions of the critical steps and parameters that enable reproducibly robust cellular differentiation in vitro. It is in the interest of the field to consider wider adoption of this technology, as it has the potential to reduce animal use, lower the cost and shorten the timelines of both basic and translational experimentation.

Derivation of T Cells In Vitro from Mouse Embryonic Stem Cells

Mouse embryonic stem cells can be differentiated to T cells in vitro using the OP9-DL1 co-culture system. Success in this procedure requires careful attention to reagent/cell maintenance, and key technique sensitive steps. Here we discuss these critical parameters and provide a detailed protocol to encourage adoption of this technology.

对T细胞推导<em&gt;在体外</em&gt;从小鼠胚胎干细胞

The OP9/OP9-DL1 co-culture system has become a well-established method for deriving differentiated blood cell types from embryonic and hematopoietic ...

Generation of Human Alloantigen-specific T Cells from Peripheral Blood

The study of human T lymphocyte biology often involves examination of responses to activating ligands. T cells recognize and respond to processed peptide antigens presented by MHC (human ortholog HLA) molecules through the T cell receptor (TCR) in a highly sensitive and specific manner. While the primary function of T cells is to mediate protective immune responses to foreign antigens presented by self-MHC, T cells respond robustly to antigenic differences in allogeneic tissues. T cell responses to alloantigens can be described as either direct or indirect alloreactivity. In alloreactivity, the T cell responds through highly specific recognition of both the presented peptide and the MHC molecule. The robust oligoclonal response of T cells to allogeneic stimulation reflects the large number of potentially stimulatory alloantigens present in allogeneic tissues. While the breadth of alloreactive T cell responses is an important factor in initiating and mediating the pathology associated with biologically-relevant alloreactive responses such as graft versus host disease and allograft rejection, it can preclude analysis of T cell responses to allogeneic ligands. To this end, this protocol describes a method for generating alloreactive T cells from naive human peripheral blood leukocytes (PBL) that respond to known peptide-MHC (pMHC) alloantigens. The protocol applies pMHC multimer labeling, magnetic bead enrichment and flow cytometry to single cell in vitro culture methods for the generation of alloantigen-specific T cell clones. This enables studies of the biochemistry and function of T cells responding to allogeneic stimulation.

This article describes a method for the generation and propagation of human T cell clones that specifically respond to a defined alloantigen. This protocol can be adapted for cloning human T cells specific for a variety of peptide-MHC ligands.

从外周血人类同种异体抗原特异性T细胞的生成

The study of human T lymphocyte biology often involves examination of responses to activating ligands. T cells recognize and respond to processed peptide ...

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.

性T细胞Transinfection从树突状细胞捕捉细菌

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

Phenotypic and Functional Analysis of Activated Regulatory T Cells Isolated from Chronic Lymphocytic Choriomeningitis Virus-infected Mice

Regulatory T (Treg) cells, which express Foxp3 as a transcription factor, are subsets of CD4+ T cells. Treg cells play crucial roles in immune tolerance and homeostasis maintenance by regulating the immune response. The primary role of Treg cells is to suppress the proliferation of effector T (Teff) cells and the production of cytokines such as IFN-&#947;, TNF-&#945;, and IL-2. It has been demonstrated that Treg cells&#39; ability to inhibit the function of Teff cells is enhanced during persistent pathogen infection and cancer development. To clarify the function of Treg cells under resting or inflamed conditions, a variety of in vitro suppression assays using mouse or human Treg cells have been devised. The main aim of this study is to develop a method to compare the differences in phenotype and suppressive function between resting and activated Treg cells. To isolate activated Treg cells, mice were infected with lymphocytic choriomeningitis virus (LCMV) clone 13 (CL13), a chronic strain of LCMV. Treg cells isolated from the spleen of LCMV CL13-infected mice exhibited both the activated phenotype and enhanced suppressive activity compared with resting Treg cells isolated from na&#239;ve mice. Here, we describe the basic protocol for ex vivo phenotype analysis to distinguish activated Treg cells from resting Treg cells. Furthermore, we describe a protocol for the measurement of the suppressive activity of fully activated Treg cells.

Here, we describe a protocol to analyze the phenotype of regulatory T (Treg) cells isolated from na&#239;ve and chronic lymphocytic choriomeningitis virus-infected mice. In addition, we provide a process to evaluate the suppressive activity of the Treg cells.

表型和慢性淋巴细胞性脉络丛脑膜炎病毒感染小鼠中分离激活调节性T细胞的功能分析

Regulatory T (Treg) cells, which express Foxp3 as a transcription factor, are subsets of CD4+ T cells. Treg cells play crucial roles in immune tolerance ...

Development of Stem Cell-derived Antigen-specific Regulatory T Cells Against Autoimmunity

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic self-tolerance. Tregs represent about 5 - 10% of the mature CD4+ T cell subpopulation in mice and humans, with about 1 - 2% of those Tregs circulating in the peripheral blood. Induced pluripotent stem cells (iPSCs) can be differentiated into functional Tregs, which have a potential to be used for cell-based therapies of autoimmune diseases. Here, we present a method to develop antigen (Ag)-specific Tregs from iPSCs (i.e., iPSC-Tregs). The method is based on incorporating the transcription factor FoxP3 and an Ag-specific T cell receptor (TCR) into iPSCs and then differentiating on OP9 stromal cells expressing Notch ligands delta-like (DL) 1 and DL4. Following in vitro differentiation, the iPSC-Tregs express CD4, CD8, CD3, CD25, FoxP3, and Ag-specific TCR and are able to respond to Ag stimulation. This method has been successfully applied to cell-based therapy of autoimmune arthritis in a murine model. Adoptive transfer of these Ag-specific iPSC-Tregs into Ag-induced arthritis (AIA)-bearing mice has the ability to reduce joint inflammation and swelling and to prevent bone loss.

We present here a method to develop functional antigen (Ag)-specific regulatory T cells (Tregs) from induced pluripotent stem cells (iPSCs) for immunotherapy of autoimmune arthritis in a murine model.

干细胞衍生的抗原特异性调节性T细胞对自身免疫的发展

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic ...

SILAC Based Proteomic Characterization of Exosomes from HIV-1 Infected Cells

Proteomics is the large-scale analysis of proteins. Proteomic techniques, such as liquid chromatography tandem mass spectroscopy (LC-MS/MS), can characterize thousands of proteins at a time. These powerful techniques allow us to have a systemic understanding of cellular changes, especially when cells are subjected to various stimuli, such as infections, stresses, and specific test conditions. Even with recent developments, analyzing the exosomal proteome is time-consuming and often involves complex methodologies. In addition, the resultant large dataset often needs robust and streamlined analysis in order for researchers to perform further downstream studies. Here, we describe a SILAC-based protocol for characterizing the exosomal proteome when cells are infected with HIV-1. The method is based on simple isotope labeling, isolation of exosomes from differentially labeled cells, and mass spectrometry analysis. This is followed by detailed data mining and bioinformatics analysis of the proteomic hits. The resultant datasets and candidates are easy to understand and often offer a wealth of information that is useful for downstream analysis. This protocol is applicable to other subcellular compartments and a wide range of test conditions.

Here, we describe a quantitative proteomics method using the technique of stable isotope labeling by amino acids in cell culture (SILAC) to analyze the effects of HIV-1 infection on host exosomal proteomes. This protocol can be easily adapted to cells under different stress or infection conditions.

从HIV-1感染细胞的外来体基于SILAC蛋白质组学表征

Proteomics is the large-scale analysis of proteins. Proteomic techniques, such as liquid chromatography tandem mass spectroscopy (LC-MS/MS), can ...

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.