Este trabalho foi financiado por doações para Keith L. Knutson da Susan G. Komen for the Cure Foundation e NIH / NCI 9R01 CA152045 e P50-CA116201.

<ol>
	<li>Zhang, N., Bevan, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD8(+)+T+cells:+foot+soldiers+of+the+immune+system.">CD8(+) T cells: foot soldiers of the immune system.</a> Immunity. 35, 161-168 (2011).</li><li>Garboczi, D. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+of+the+complex+between+human+T-cell+receptor,+viral+peptide+and+HLA-A2.">Structure of the complex between human T-cell receptor, viral peptide and HLA-A2.</a> Nature. 384, 134-141 (1996).</li><li>Knutson, K. L., dela Rosa, C., Disis, 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=Laboratory+analysis+of+T-cell+immunity.">Laboratory analysis of T-cell immunity.</a> Front Biosci. 11, 1932-1944 (2006).</li><li>Andersen, M. H., Schrama, D., Thor Straten, P., Becker, 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=.">.</a> Cytotoxic T cells. J. Invest. Dermatol. 126, 32-41 (2006).</li><li>Weren, A., Bonnekoh, B., Schraven, B., Gollnick, H., Ambach, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+flow+cytometric+assay+focusing+on+perforin+release+mechanisms+of+cytotoxic+T+lymphocytes.">A novel flow cytometric assay focusing on perforin release mechanisms of cytotoxic T lymphocytes.</a> J. Immunol. Methods. 289, 17-26 (2004).</li><li>Aktas, E., Kucuksezer, U. C., Bilgic, S., Erten, G., Deniz, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relationship+between+CD107a+expression+and+cytotoxic+activity.">Relationship between CD107a expression and cytotoxic activity.</a> Cell Immunol. 254, 149-154 (2009).</li><li>Knutson, K. L., Schiffman, K., Disis, 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=Immunization+with+a+HER-2/neu+helper+peptide+vaccine+generates+HER-+2/neu+CD8+T-cell+immunity+in+cancer+patients.">Immunization with a HER-2/neu helper peptide vaccine generates HER- 2/neu CD8 T-cell immunity in cancer patients.</a> J. Clin. Invest. 107, 477-484 (2001).</li><li>Asiedu, M. K., Ingle, J. N., Behrens, M. D., Radisky, D. C., Knutson, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TGFbeta/TNF(alpha)-mediated+epithelial-mesenchymal+transition+generates+breast+cancer+stem+cells+with+a+claudin-low+phenotype.">TGFbeta/TNF(alpha)-mediated epithelial-mesenchymal transition generates breast cancer stem cells with a claudin-low phenotype.</a> Cancer Res. 71, 4707-4719 (2011).</li><li>Strijbosch, L. W., Buurman, W. A., Does, R. J., Zinken, P. H., Groenewegen, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Limiting+dilution+assays.+Experimental+design+and+statistical+analysis.">Limiting dilution assays. Experimental design and statistical analysis.</a> J. Immunol. Methods. 97, 133-140 (1987).</li><li>Gallimore, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+and+exhaustion+of+lymphocytic+choriomeningitis+virus-specific+cytotoxic+T+lymphocytes+visualized+using+soluble+tetrameric+major+histocompatibility+complex+class+I-peptide+complexes.">Induction and exhaustion of lymphocytic choriomeningitis virus-specific cytotoxic T lymphocytes visualized using soluble tetrameric major histocompatibility complex class I-peptide complexes.</a> J. Exp. Med. 187, 1383-1393 (1998).</li></ol>

Produção e acesso gratuito deste vídeo-artigo é patrocinado pela Roche Diagnostics.

As células T CD8 + são importantes para a resposta imune adaptativa, sendo capaz de matar directamente as células infectadas ou malignas 4. Embora haja várias maneiras de medir o número de células específicas de antigénio de células T CD8 (por exemplo, ELISPOT, tetrero, citometria de fluxo), muitas vezes, é útil saber se estas células são funcionalmente citotóxico 3. O ensaio mais reconhecível para a avaliação da função citotóxica é o PCR, o qual é considerado o 4 de ensaio padrão de ouro. As principais limitações do PCR são: (1) o requisito de radioactividade, (2) a falta de sensibilidade, (3) falta de informação mecanicista, (4) para o requisito de grandes quantidades de células, e (5) acima conjunto trabalhoso. Assim, ao longo da última década, tem havido um interesse na adoção de novas estratégias para minimizar essas limitações. Mais recentes abordagens incluem aqueles que medem caspase release 4, BLT esterase activity5 e expressão de superfície de CD107 6. O presente manuscrito sugere queo ensaio com base na impedância, executadas no sistema de xCELLigence Roche, podem também ser úteis como uma alternativa para a PCR. A capacidade de se adaptar a abordagem baseada em impedância baseia-se na observação de que as células T, que não aderem firmemente às superfícies, não parecem ter muito impacto sobre impedância diminuindo, assim, qualquer preocupação de interferência direta das células T com a medição. A mão de obra necessária para a utilização do sistema de ensaio da impedância deve ser significativamente menos principalmente devido à eliminação das preocupações regulamentares para a utilização de radioactividade. A única desvantagem notável do sistema baseado na impedância é que um dispêndio de $ 50.000 a $ 60.000 é necessária para a aquisição da unidade de xCELLigence. No entanto, a unidade xCELLigence elimina a necessidade de um contador de radiação e é muito mais versátil, sendo útil para avaliar a resposta celular aos medicamentos e à migração, além de citotoxicidade de células T 8. As observações de quea diminuição na impedância de células de tumor é dependente da dose, como ilustrado na Figura 2, com uma inclinação relativamente acentuada na sequência de uma função quadrática simples secundário sugere que o ensaio pode ser utilizado em ensaios de diluição limitante (ADLs) para estimar a frequência de células citotóxicas 9 . Uma vantagem da abordagem baseada em impedância é que o número de células T e células tumorais exigido é inferior ao CRA, tornando LDA potencialmente mais viável. Por exemplo, na PCR, a uma razão 1:40, 1 x 10 5 células por poço tumorais são banhados que necessita de 4 x 10 6 células T totais por poço. No entanto, no ensaio baseado em impedância, são necessários apenas 1,5 x 4 10 células tumorais por poço, que consome apenas 6 x 10 5 células T totais por poço. Deste modo, o ensaio baseado em impedância utiliza 85% menos células T e as células tumorais. Esta redução indica que o sistema à base de impedância pode ser adaptado para monitorização imunológica em ensaios clínicos em humanos em que tele volumes de sangue chama pode ser limitada. Além disso, enquanto que a PCR se limita a um único ponto de tempo, o ensaio baseado em impedância recolhe dados contínua em tempo real, permitindo ao utilizador comparar vários pontos de tempo de lise no mesmo experimento com um mínimo de trabalho adicional e células. Cálculos de frequência poderia ser combinado com outras estratégias que não medem função como tetrâmero análises para determinar a proporção de células T citotóxicas ao total funcionais específicos para o antigénio das células T CD8 10. Uma das características mais atraentes da abordagem baseada na impedância é que, ao contrário da maioria dos outros ensaios, citotoxicidade pode ser monitorado em tempo real, o que poderia tornar mais fácil para estudar as interações celulares com o uso de inibidores ou anticorpos. Outra é que o método pode ser adequado para as células de tumor que resistem a rotulagem. Finalmente, uma vez que as células tumorais não são mortas não marcado e permanece esterilizado, mais colheita e estudo das células T de células resistentes é possívle. Em resumo, embora ambos os sistemas fornecem tumorais matam dados em resposta a células T específicas, o ensaio baseado em impedância é mais sensível do que o PCR e proporciona uma plataforma mais flexível.

<table border="1">
 <tbody>
 <tr>
 <td>Name of reagent</td>
 <td>Company</td>
 <td>Catalog number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Ficoll-Paque Plus </td>
 <td>GE Healthcare </td>
 <td>17-1440-03 </td>
 <td>Used to isolate PBMCs from blood </td>
 </tr>
 <tr>
 <td>RPMI 1640 </td>
 <td>Cellgro </td>
 <td>10-040-CV </td>
 <td>Cell culture media </td>
 </tr>
 <tr>
 <td>FBS </td>
 <td>Denville Scientific </td>
 <td>FB5001-H </td>
 <td>Cell culture media </td>
 </tr>
 <tr>
 <td>Human IL-2 </td>
 <td>eBioscience </td>
 <td>14-8029-81 </td>
 <td>For stimulating growth of T cells </td>
 </tr>
 <tr>
 <td>Human Interferon gamma </td>
 <td>Cell Sciences </td>
 <td>CR2026 </td>
 <td>For stimulating MHC expression in tumor cells </td>
 </tr>
 <tr>
 <td>HER-2/neu p369-377 peptide </td>
 <td>Mayo Clinic peptide synthesis core </td>
 <td>amino acid sequence KIFGSLAFL </td>
 <td>Binds to HLA-A2 </td>
 </tr>
 <tr>
 <td>Influenza p58-66 peptide </td>
 <td>Mayo Clinic peptide synthesis core </td>
 <td>amino acid sequence GILGFVFTL </td>
 <td>Binds to HLA-A2 </td>
 </tr>
 <tr>
 <td>Human CD3/CD28 Dynabeads </td>
 <td>Invitrogen </td>
 <td>111-61D </td>
 <td>For non-specific T cell activation and expansion </td>
 </tr>
 <tr>
 <td>Chromium-51 </td>
 <td>MP Biomedicals </td>
 <td>62015 </td>
 <td>CRA labeling reagent </td>
 </tr>
 <tr>
 <td>E-plate </td>
 <td>Roche Applied Science </td>
 <td>05469830001 </td>
 <td>For xCelligence impedance unit </td>
 </tr>
 <tr>
 <td>Luma plate 96 </td>
 <td>Perkin Elmer </td>
 <td>6005630 </td>
 <td>For measuring radioactivity in the Top Count NXT. </td>
 </tr>
 <tr>
 <td>xCelligence RTCA DP Station </td>
 <td>Roche Applied Science </td>
 <td>RTCA DP </td>
 <td>Impedance unit </td>
 </tr>
 <tr>
 <td>Top Count NXT </td>
 <td>Perkin Elmer </td>
 <td>C990601 </td>
 <td>Scintillation &amp; Luminescence Counter </td>
 </tr>
 <tr>
 <td>Fas Ligand antibody</td>
 <td>BD Biosciences</td>
 <td>556372</td>
 <td>For blocking Fas-Fas ligand interactions</td>
 </tr>
 <tr>
 <td>HLA-A2 BB7.2 antibody</td>
 <td>BD Biosciences</td>
 <td>551230</td>
 <td>For blocking HLA class I</td>
 </tr>
 <tr>
 <td>Mouse IgG2b, &kappa;</td>
 <td>BD Biosciences</td>
 <td>555740</td>
 <td>Isotype control for HLA class I</td>
 </tr>
 <tr>
 <td>SKBR3 tumor line</td>
 <td>ATCC</td>
 <td>HTB-30</td>
 <td>Adenocarcinoma</td>
 </tr>
 <tr>
 <td>MCF7 tumor line</td>
 <td>ATCC</td>
 <td>HTB-22</td>
 <td>Adenocarcinoma</td>
 </tr>
 <tr>
 <td>HCC1419 tumor line</td>
 <td>ATCC</td>
 <td>CRL-2326</td>
 <td>Primary ductal carcinoma</td>
 </tr>
 <tr>
 <td>BT20 tumor line</td>
 <td>ATCC</td>
 <td>HTB-19</td>
 <td>Carcinoma</td>
 </tr>
 </tbody>
</table>

determining optimal cytotoxic activity of human her2neu specific cd8 t cells by comparing the cr51 release assay to the xcelligence system

As células T citotóxicas CD8 constituem um subgrupo de células T que são capazes de induzir a morte das células hospedeiras infectadas ou malignas 1. Estas células expressam um receptor especializado, chamado o receptor de células T (TCR), que reconhece um péptido antigénico específico ligado a moléculas de HLA de classe I 2. Acoplamento de células infectadas ou células tumorais, através das suas molécula de HLA de classe I resulta na produção de moléculas líticas, tais como perforina e granzimas, resultando na morte de células alvo. Embora seja útil para determinar a frequência de células específicas para o antigénio T CD8 + utilizando ensaios tais como o ELISPOT ou citometria de fluxo, também é útil para determinar a força de respostas de células T CD8 + utilizando ensaios de citotoxicidade 3. O ensaio mais reconhecível para a avaliação da função citotóxica é o ensaio de libertação de crómio (PCR), que é considerado um ensaio padrão 4. A PCR tem várias limitações, incluindo a exposição de células a radiação gama, lack de reprodutibilidade, e um requisito para um grande número de células. Ao longo da última década, tem havido um interesse na adoção de novas estratégias para superar essas limitações. Mais recentes abordagens incluem aqueles que medem caspase release 4, BLT atividade esterase 5 e expressão de superfície de CD107 6. O ensaio à base de impedância, utilizando o sistema de xCELLigence Roche, foi examinada no presente documento, para o seu potencial como uma alternativa para a PCR. Impedância ou oposição a uma corrente eléctrica ocorre quando as células tumorais aderentes ligam a placas de eléctrodos. As células tumorais separar após abate e impedância eléctrica é reduzida, o que pode ser medido pelo sistema xCELLigence. A capacidade de se adaptar a abordagem baseada em impedância para avaliar a morte mediada por células, baseia-se na observação de que as células T não aderem bem à maioria das superfícies e que não parecem ter grande impacto na impedância diminuindo assim qualquer preocupação de interferência directa das células T coma medição. Os resultados mostram que o ensaio à base de impedância pode detectar alterações nos níveis de células T citotóxicas CD8 + específicas para o antigénio, com sensibilidade aumentada em relação ao padrão de PCR. Com base nesses resultados, as abordagens baseadas em impedância podem ser boas alternativas para CRAs ou outras abordagens que visam medir a funcionalidade das células T CD8 citotóxico.

Watch this Scientific Journal Video about Determining Optimal Cytotoxic Activity of Human Her2neu Specific CD8 T cells by Comparing the Cr51 Release Assay to the xCELLigence System at JoVE.com

Determining Optimal Cytotoxic Activity of Human Her2neu Specific CD8 T cells by Comparing the Cr51 Release Assay to the xCELLigence System

O ensaio de libertação de crómio, um ensaio comum para a detecção da actividade de células T citotóxicas, tem várias limitações. Usando células T CD8 específicos de antígenos ea linha de tumor de câncer de mama humano, SKBR3, no presente artigo, uma abordagem baseada em impedância foi examinado para a capacidade de detecção de morte celular.

Determinando a atividade citotóxica Optimal específicos de células CD8 Her2neu Humanos T, comparando a Cr51 Ensaio de Libertação do Sistema xCELLigence

Cytotoxic CD8 T cells constitute a subgroup of T  cells that are capable of inducing the death of infected or malignant host  cells1. These cells express ...

determining-optimal-cytotoxic-activity-human-her2neu-specific-cd8-t

Research

JoVE Journal

Immunology and Infection

24.9K visualizações.  College of Medicine, Mayo Clinic. O ensaio de libertação de crómio, um ensaio comum para a detecção da actividade de células T citotóxicas, tem várias limitações. Usando células T CD8 específicos de antígenos ea linha de tumor de câncer de mama humano, SKBR3, no presente artigo, uma abordagem baseada em impedância foi examinado para a capacidade de detecção de morte celular.

Vídeo: Determining Optimal Cytotoxic Activity of Human Her2neu Specific CD8 T cells by Comparing the Cr51 Release Assay to the xCELLigence System

Methods to Assess Beta Cell Death Mediated by Cytotoxic T Lymphocytes

Type 1 diabetes (T1D) is a T cell mediated autoimmune disease. During the pathogenesis, patients become progressively more insulinopenic as 
insulin production is lost, presumably this results from the destruction of pancreatic beta cells by T cells. Understanding the mechanisms of beta cell death during 
the development of T1D will provide insights to generate an effective cure for this disease. Cell-mediated lymphocytotoxicity (CML) assays have historically used the 
radionuclide Chromium 51 (51Cr) to label target cells. These targets are then exposed to effector cells and the release of 51Cr from target 
cells is read as an indication of lymphocyte-mediated cell death. Inhibitors of cell death result in decreased release of 51Cr.
 As effector cells, we used an activated autoreactive clonal population of CD8+ Cytotoxic T lymphocytes (CTL) isolated from a mouse stock transgenic for both the alpha and beta chains of the AI4 T cell receptor (TCR). Activated AI4 T cells were co-cultured with 51Cr labeled target NIT cells for 16 hours, release of 51Cr was recorded to calculate specific lysis 
Mitochondria participate in many important physiological events, such as energy production, regulation of signaling transduction, and apoptosis. The study of beta cell mitochondrial functional changes during the development of T1D is a novel area of research. Using the mitochondrial membrane potential dye Tetramethyl Rhodamine Methyl Ester (TMRM) and confocal microscopic live cell imaging, we monitored mitochondrial membrane potential over time in the beta cell line NIT-1. For imaging studies, effector AI4 T cells were labeled with the fluorescent nuclear staining dye Picogreen. NIT-1 cells and T cells were co-cultured in chambered coverglass and mounted on the microscope stage equipped with a live cell chamber, controlled at 37&deg;C, with 5% CO2, and humidified. During these experiments images were taken of each cluster every 3 minutes for 400 minutes.
Over a course of 400 minutes, we observed the dissipation of mitochondrial membrane potential in NIT-1 cell clusters where AI4 T cells were attached. In the simultaneous control experiment where NIT-1 cells were co-cultured with MHC mis-matched human lymphocyte Jurkat cells, mitochondrial membrane potential remained intact. This technique can be used to observe real-time changes in mitochondrial membrane potential in cells under attack of cytotoxic lymphocytes, cytokines, or other cytotoxic reagents.

Cell-mediated lymphocytotoxicity (CML) assays can be used to test autoreactive responses and study mechanisms of cell death in vitro. However, using live-cell confocal microscopic imaging techniques with fluorescent dyes, the type and kinetics of cell death as well as the pathways utilized can be studied in greater detail.

Métodos para avaliar Mediated Beta Morte celular por linfócitos T citotóxicos

Type 1 diabetes (T1D) is a T cell mediated autoimmune disease.  During the pathogenesis, patients become progressively more insulinopenic as 
insulin ...

Imunologia e Infecção

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

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

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

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

In Vitro Ensaio para avaliar o impacto da imunorreguladora Pathways on específica para o HIV CD4 T efetoras celular Função

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

Cell-based Flow Cytometry Assay to Measure Cytotoxic Activity

Cytolytic activity of CD8+ T cells is rarely evaluated. We describe here a new cell-based assay to measure the capacity of antigen-specific CD8+ T cells to kill CD4+ T cells loaded with their cognate peptide. Target CD4+ T cells are divided into two populations, labeled with two different concentrations of CFSE. One population is pulsed with the peptide of interest (CFSE-low) while the other remains un-pulsed (CFSE-high). Pulsed and un-pulsed CD4+ T cells are mixed at an equal ratio and incubated with an increasing number of purified CD8+ T cells. The specific killing of autologous target CD4+ T cells is analyzed by flow cytometry after coculture with CD8+ T cells containing the antigen-specific effector CD8+ T cells detected by peptide/MHCI tetramer staining. The specific lysis of target CD4+ T cells measured at different effector versus target ratios, allows for the calculation of lytic units, LU30/106 cells. This simple and straightforward assay allows for the accurate measurement of the intrinsic capacity of CD8+ T cells to kill target CD4+ T cells.

This protocol describes a sensitive, cell-based cytotoxicity assay. By enumerating the decrease in frequency of live target CD4+ T cells in the presence of an increasing number of effector CD8+ T cells, this assay allows for the direct assessment of cytolytic activity of antigen-specific CD8+ T cells.

Baseada em células de Citometria de Fluxo Ensaio medir citotóxicos Atividade

Cytolytic activity of CD8+ T cells is rarely evaluated. We describe here a new cell-based assay to measure the capacity of antigen-specific CD8+ T cells ...

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.

Avaliando a inata Sensing de HIV-1 CD4 Infected<sup&gt; +</sup&gt; As células T por células dendríticas plasmocitóides Usando um<em&gt; Ex vivo</em&gt; Co-cultura do sistema.

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

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.

Geração de Células T humanas alo-específicos a partir de Sangue Periférico

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

Automated Cell Enrichment of Cytomegalovirus-specific T cells for Clinical Applications using the Cytokine-capture System

The adoptive transfer of pathogen-specific T cells can be used to prevent and treat opportunistic infections such as cytomegalovirus (CMV) infection occurring after allogeneic hematopoietic stem-cell transplantation. Viral-specific T cells from allogeneic donors, including third party donors, can be propagated ex vivo in compliance with current good manufacturing practice (cGMP), employing repeated rounds of antigen-driven stimulation to selectively propagate desired T cells. The identification and isolation of antigen-specific T cells can also be undertaken based upon the cytokine capture system of T cells that have been activated to secrete gamma-interferon (IFN-&#947;). However, widespread human application of the cytokine capture system (CCS) to help restore immunity has been limited as the production process is time-consuming and requires a skilled operator. The development of a second-generation cell enrichment device such as CliniMACS Prodigy now enables investigators to generate viral-specific T cells using an automated, less labor-intensive system. This device separates magnetically labeled cells from unlabeled cells using magnetic activated cell sorting technology to generate clinical-grade products, is engineered as a closed system and can be accessed and operated on the benchtop. We demonstrate the operation of this new automated cell enrichment device to manufacture CMV pp65-specific T cells obtained from a steady-state apheresis product obtained from a CMV seropositive donor. These isolated T cells can then be directly infused into a patient under institutional and federal regulatory supervision. All the bio-processing steps including removal of red blood cells, stimulation of T cells, separation of antigen-specific T cells, purification, and washing are fully automated. Devices such as this raise the possibility that T cells for human application can be manufactured outside of dedicated good manufacturing practice (GMP) facilities and instead be produced in blood banking facilities where staff can supervise automated protocols to produce multiple products.

The goal of this protocol is to manufacture pathogen-specific clinical-grade T cells using a bench-top, automated, second generation cell enrichment device that incorporates a closed cytokine capture system and does not require dedicated staff or use of a GMP facility. The cytomegalovirus pp65-specific-T cells generated can be directly administered to patients.

As células T de enriquecimento de células automatizado de citomegalovírus específico-para aplicações clínicas usando o Sistema de captura de citocinas

The adoptive transfer of pathogen-specific T cells can be used to prevent and treat opportunistic infections such as cytomegalovirus (CMV) infection ...

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.

Desenvolvimento de Células-Tronco de derivados de células T regulatórias antígeno específico da Contra Auto-imunidade

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

Analysis of Simian Immunodeficiency Virus-specific CD8+ T-cells in Rhesus Macaques by Peptide-MHC-I Tetramer Staining

Peptide-major histocompatibility complex class I (pMHC-I) tetramers have been an invaluable tool to study CD8+ T-cell responses. Because these reagents directly bind to T-cell receptors on the surface of CD8+ T-lymphocytes, fluorochrome-labeled pMHC-I tetramers enable the accurate detection of antigen (Ag)-specific CD8+ T-cells without the need for in vitro re-stimulation. Moreover, when combined with multi-color flow cytometry, pMHC-I tetramer staining can reveal key aspects of Ag-specific CD8+ T-cells, including differentiation stage, memory phenotype, and activation status. These types of analyses have been especially useful in the field of HIV immunology where CD8+ T-cells can affect progression to AIDS. Experimental infection of rhesus macaques with simian immunodeficiency virus (SIV) provides an invaluable tool to study cellular immunity against the AIDS virus. As a result, considerable progress has been made in defining and characterizing T-cell responses in this animal model. Here we present an optimized protocol for enumerating SIV-specific CD8+ T-cells in rhesus macaques by pMHC-I tetramer staining. Our assay permits the simultaneous quantification and memory phenotyping of two pMHC-I tetramer+ CD8+ T-cell populations per test, which might be useful for tracking SIV-specific CD8+ T-cell responses generated by vaccination or SIV infection. Considering the relevance of nonhuman primates in biomedical research, this methodology is applicable for studying CD8+ T-cell responses in multiple disease settings.

Analysis of Simian Immunodeficiency Virus-specific CD8+ T-cells in Rhesus Macaques by Peptide-MHC-I Tetramer Staining

Here, we present an optimized protocol for enumerating and characterizing rhesus macaque CD8+ T cells against the AIDS virus. This article is useful not only to the field of HIV immunology, but also to other areas of biomedical research where CD8+ T cell responses are known to affect disease outcome.

Análise de células T CD8 específicas do vírus da imunodeficiência símia<sup&gt; +</sup&gt; Células-T em Rhesus Macaques por Peptide-MHC-I tetrâmero coloração

Peptide-major histocompatibility complex class I (pMHC-I) tetramers have been an invaluable tool to study CD8+ T-cell responses. Because these reagents ...

In Situ MHC-tetramer Staining and Quantitative Analysis to Determine the Location, Abundance, and Phenotype of Antigen-specific CD8 T Cells in Tissues

T cells are critical to many immunological processes, including detecting and eliminating virus-infected cells, preventing autoimmunity, assisting in B-cell and plasma-cell production of antibodies, and detecting and eliminating cancer cells. The development of MHC-tetramer staining of antigen-specific T cells analyzed by flow cytometry has revolutionized our ability to study and understand the immunobiology of T cells. While extremely useful for determining the quantity and phenotype of antigen-specific T cells, flow cytometry cannot determine the spatial localization of antigen-specific T cells to other cells and structures in tissues, and current disaggregation techniques to extract the T cells needed for flow cytometry have limited effectiveness in non-lymphoid tissues. In situ MHC-tetramer staining (IST) is a technique to visualize T cells that are specific for antigens of interest in tissues. In combination with immunohistochemistry (IHC), IST can determine the abundance, location, and phenotype of antigen-specific CD8 and CD4 T cells in tissues. Here, we describe a protocol to stain and enumerate antigen-specific CD8 T cells, with specific phenotypes located within specific tissue compartments. These procedures are the same that we used in our recent publication by Li et al., entitled &#34;Simian Immunodeficiency Virus-Producing Cells in Follicles Are Partially Suppressed by CD8+ Cells In Vivo.&#34; The methods described are broadly applicable because they can be used to localize, phenotype, and quantify essentially any antigen-specific CD8 T cell for which MHC tetramers are available, in any tissue.

In Situ MHC-tetramer Staining and Quantitative Analysis to Determine the Location, Abundance, and Phenotype of Antigen-specific CD8 T Cells in Tissues

Here, we describe a method that combines in situ MHC-tetramer staining with immunohistochemistry to determine localization, phenotype, and quantity of antigen-specific T cells in tissues. This protocol is used to determine the spatial and phenotypic characteristics of antigen-specific CD8 T cells relative to other cell type and structures in tissues.

In Situ MHC-tetrâmero manchando e análise quantitativa para determinar a localização, abundância e fenótipo de células T de CD8 antígeno-específicas em tecidos

T cells are critical to many immunological processes, including detecting and eliminating virus-infected cells, preventing autoimmunity, assisting in ...

Tailoring In Vivo Cytotoxicity Assays to Study Immunodominance in Tumor-specific CD8+ T Cell Responses

Carboxyfluorescein succinimidyl ester (CFSE)-based in vivo cytotoxicity assays enable sensitive and accurate quantitation of CD8+ cytolytic T lymphocyte (CTL) responses elicited against tumor- and pathogen-derived peptides. They offer several advantages over traditional killing assays. First, they permit the monitoring of CTL-mediated cytotoxicity within architecturally intact secondary lymphoid organs, typically in the spleen. Second, they allow for mechanistic studies during the priming, effector and recall phases of CTL responses. Third, they provide useful platforms for vaccine/drug efficacy testing in a truly in vivo setting. Here, we provide an optimized protocol for the examination of concomitant CTL responses against more than one peptide epitope of a model tumor antigen (Ag), namely, simian virus 40 (SV40)-encoded large T Ag (T Ag). Like most other clinically relevant tumor proteins, T Ag harbors many potentially immunogenic peptides. However, only four such peptides induce detectable CTL responses in C57BL/6 mice. These responses are consistently arranged in a hierarchical order based on their magnitude, which forms the basis for TCD8 &#8220;immunodominance&#8221; in this powerful system. Accordingly, the bulk of the T Ag-specific TCD8 response is focused against a single immunodominant epitope while the other three epitopes are recognized and responded to only weakly. Immunodominance compromises the breadth of antitumor TCD8 responses and is, as such, considered by many as an impediment to successful vaccination against cancer. Therefore, it is important to understand the cellular and molecular factors and mechanisms that dictate or shape TCD8 immunodominance. The protocol we describe here is tailored to the investigation of this phenomenon in the T Ag immunization model, but can be readily modified and extended to similar studies in other tumor models. We provide examples of how the impact of experimental immunotherapeutic interventions can be measured using in vivo cytotoxicity assays.

Tailoring In Vivo Cytotoxicity Assays to Study Immunodominance in Tumor-specific CD8+ T Cell Responses

We describe here a flow cytometry-based in vivo killing assay that enables examination of immunodominance in cytotoxic T lymphocyte (CTL) responses to a model tumor antigen. We provide examples of how this elegant assay may be employed for mechanistic studies and for drug efficacy testing.

Adaptando os ensaios de citotoxicidade in vivo para estudar Imunodominância em respostas de células T CD8+ específicas do tumor

Carboxyfluorescein succinimidyl ester (CFSE)-based in vivo cytotoxicity assays enable sensitive and accurate quantitation of CD8+ cytolytic T lymphocyte ...