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...

Com mais de 34 milhões de pessoas que vivem com HIV / AIDS em todo o mundo e um número estimado de 2,5 milhões de pessoas infectadas em 2011, a necessidade de uma vacina anti-HIV eficaz para conter a epidemia de HIV em todo o mundo continua a ser fundamental. No entanto, apesar de três décadas de esforços de pesquisa intensa, a HIV-1 vacina ensaios de eficácia até à data resultaram em apenas uma proteção modesta 1-3 e os correlatos de imunidade protetora continuam a ser mal compreendido. Elucidar a natureza da resposta imunitária necessária para a protecção é essencial para a criação de uma estratégica eficaz contra o HIV-1, vacina e outras estratégias imunoterapêuticas objectivo infecção HIV-1. Naturais CD4 + células T reguladoras (Tregs) são essenciais para a manutenção da homeostase imune celular, controlando a activação imunitária excessiva, limitando, assim, danos no tecido imune-mediada. No entanto, eles também podem suprimir as respostas imunes contra os agentes patogénicos e evitar a sua recarga. Câncer e Hepaestudos de vacinas Callicebus B têm demonstrado que a diminuição da actividade de Tregs pode melhorar a resposta à vacina e antigénio específico da imunidade contra vírus 4-7. No entanto, no contexto da infecção pelo HIV-1, o impacto exato de células T reguladoras permanece incompletamente compreendida. Tregs foram mostrados para diminuir a replicação do vírus em células T ativadas 8 e possivelmente impactar ativação imune 9. Eles também foram mostrados para suprimir respostas imunes-1 HIV-específicas, que poderão ter resultados negativos para a progressão da doença 10,11. Assim, antes de ser capaz de modular a actividade Treg para aumentar a eficácia de uma vacina contra o HIV-1, que é ainda mais importante para ganhar conhecimento sobre a sua função no contexto da doença. As células T reguladoras CD4 + humanas são uma população de células relativamente raras, o que representa cerca de 5% de células T CD4 + no sangue periférico, e os seus números absolutos decréscimo adicional de CD4 com o HIV-associados + depleção de células T 12 &lt;/ Sup&gt;. Ensaios atuais para avaliar a função Treg, tais como ensaios de proliferação de células T com Treg co-cultura, use o número de células relativamente grandes 12. Portanto, a função e a especificidade das células T reguladoras caracterizar em indivíduos com doença avançada da doença do HIV-1 tem sido um desafio, apesar da sua importância para a patogénese do VIH. O isolamento e a expansão ex vivo de Tregs de pacientes de HIV-1 pode representar uma solução para ultrapassar algumas destas limitações. Aqui nós descrevemos um protocolo fácil e robusta para expandir Tregs funcional derivado de HIV-1 indivíduos infectados in vitro, nós ainda explicar como fenótipo-los e testar sua função de supressão utilizando ensaios de citometria de fluxo. Acreditamos que este protocolo vai facilitar o acesso a Tregs e ajudar a compreender o seu papel no HIV-1 a progressão da doença.

<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 + células T reguladoras (Tregs) são moduladores imunes potentes e têm uma função importante na homeostase imune humano. Esgotamento das Tregs levou a aumentos mensuráveis ​​nas respostas de células T antígeno-específicas em ambientes de vacina para o câncer e agentes infecciosos. Contudo, o seu papel no VIH-1 imuno-patogénese permanece controverso, visto que pode servir tanto para suprimir a activação imunitária ao HIV-1 e, portanto, associada deletério retardar a progressão da doença VIH-1, ou, alternativamente, suprimir a imunidade específica do HIV-1 e, assim, promover a vírus se espalhar. Compreender e função moduladora Treg no contexto do HIV-1 pode conduzir a novas estratégias potenciais para a imunoterapia ou vacinas contra o HIV. Contudo, questões importantes permanecem abertas sobre a sua função no contexto da infecção pelo HIV-1, que tem de ser cuidadosamente estudada. Representando aproximadamente 5% das células T no sangue periférico CD4 + humanas, estudar a população Treg provou ser difícil, EScipalmente no VIH-1, em que os indivíduos infectados com HIV-1 de células T CD4 associada e com que a depleção de Treg ocorre. A caracterização de células T reguladoras, em indivíduos com doença avançada da doença do HIV-1 ou amostras de tecido, para o qual apenas pequenas amostras biológicas podem ser obtidos, é, portanto, extremamente desafiador. Propomos uma solução técnica para ultrapassar estas limitações, com isolamento e expansão de Tregs de indivíduos infectados pelo HIV-1 positivas. Aqui, nós descrevemos um método fácil e robusto para desenvolver com sucesso Tregs isolado a partir de indivíduos infectados pelo HIV-1-infected in vitro. Fluxo-ordenadas CD3 + CD4 + CD25 + CD127 acessível Tregs foram estimuladas com anti-CD3/anti-CD28 grânulos revestidos e cultivadas na presença de IL-2. O expandida Tregs expressa níveis elevados de FOXP3, CTLA4 e Helios em comparação com as células T convencionais e mostraram ser altamente supressiva. Acesso mais fácil a um grande número de Tregs permitirá aos investigadores para lidar com important perguntas sobre o seu papel no HIV-1 imunopatogênese. Acreditamos responder a estas perguntas podem fornecer informações úteis para o desenvolvimento de uma vacina contra o HIV-1 eficaz.

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.

Novas ferramentas para expandir as células T reguladoras de indivíduos HIV-1-infected

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 visualizações.  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.