Questo lavoro è stato sostenuto dalle concessioni dal National Institutes of Health DK074656 e AI56374 (CEM), così come la Juvenile Diabetes Research Foundation.

1. Preparazione di cellule <ol><li> Obiettivo coltura cellulare: Cultura delle linee di cellule beta del mouse, NIT-1 e NIT-4, era un 1,2 precedentemente descritta in DMEM supplementato con 10% FBS, 0,02% BSA, non aminoacidi essenziali, HEPES 15mm, 16,5 mm Glocose e penicillina / streptomicina. Per 51 etichettatura Cr, le cellule di semi in un piatto fondo da 96 pozzetti alla piastra di coltura 5X10 4 cellule / pozzetto in 200 microlitri terreno di coltura. Per gli esperimenti di microscopia, le cellule di semi in un 8-ben Lab-Tak II chambered coprioggetti 5x10 a 4 per camera in 500 microlitri terreno di coltura, e consentono di crescere per 48 ore prima di utilizzare negli esperimenti di citotossicità. </li><li> Controllo di colture cellulari linea T: Utilizzare la riga di cellule Jurkat (ATCC, CD3 + umano linea cellulare dei linfociti) come controllo negativo. Cellule in coltura Jurkat RPMI1640 supplementato con 10% FBS, 2 mM L-glutammina, 1,5 g / L di bicarbonato di sodio, 10 HEPES mM e 1.0 mM di piruvato di sodio. </li></ol> 2. La raccolta e l&#39;attivazione di effettori autoreattivi cellule T CD8 + NOD.Cg-RAG1 tm1Mom Tg (TcraAI4) 1Dvs/DvsJ [NOD-AI4a] e NOD.Cg-RAG1 tm1Mom Tg (TcrbAI4) 1Dvs/DvsJ [NOD-AI4b] sono stati acquistati da The Jackson Laboratory (Bar Harbor, ME) e allevati nella nostra struttura mouse. F1 progenie ibrida da accoppiamenti di NOD-AI4a con NOD-AI4b [NOD-AI4a / b] sviluppare il diabete a 3-5 settimane di età. Tutti i topi sono stati ospitati in specifici esenti da organismi patogeni strutture e approvato dalla cura degli animali all&#39;istituzione competente e del comitato Usa. <ol><li> Eutanasia 3-4 settimana di vita NOD-AI4a / b topo, utilizzando CO 2. </li><li> Raccogliere milza di topi. Topi eutanasia sono preparati con spray etanolo e aperto sotto il cofano chirurgico. Milza vengono rimossi e messi in gelide tampone HBSS immediatamente. </li><li> Raccogliere le cellule della milza con un 7 ml di vetro omogeneizzatore. Due o tre ogni milza sono messi in 5 ml di HBSS freddo e omogeneizzato con una ML 7, vetro omogeneizzatore. Omogeneizzato viene raccolto e centrifugato a 1200rpm per 5 minuti a 4 ° C con una Sorvall RT7 centrifuga +. Pellet cellulari sono raccolti. </li><li> Rimuovere i globuli rossi con il trattamento ipotonico soluzione. I pellets sono trattati con 5 ml di soluzione ipotonica / milza in ghiaccio per 5 minuti, poi neutralizzato con l&#39;aggiunta di un uguale volume di HBSS. Raccogliere le cellule per centrifugazione, come sopra, e risospendere in 50 HBSS ml. Passare attraverso le cellule sospese filtro cellulare e conta con un emocitometro con colorazione TrypanBlue. </li><li> Attivare le cellule. Risospendere le cellule a 5x10 6 / ml e attivare utilizzando una cultura 3 giorni con 0,1 mM AI4 mimotopo (amino YFIENYLEL sequenza di acido) e 25 U / mL di IL-2 in RPMI1640 supplementato con 10% FBS, 2 mM L-glutammina, 1,5 g / L bicarbonato di sodio, 10 HEPES mM e 1.0 mM di piruvato di sodio. </li></ol> 3. 51 saggio di rilascio Cr esaminare CML <ol><li> Cellule bersaglio Etichetta: Aggiungi 51 Cr di indirizzare le cellule a 1 μCi / bene e cultura per 3 ore, e lavare 3 volte con terreno di coltura. </li><li> Sospendere cellule effettrici in RPMI 1640 medium, come indicato al punto 2,5 in modo che il volume finale aggiunti a ciascun pozzetto è di 200 microlitri. </li><li> Dopo l&#39;ultimo lavaggio delle cellule bersaglio marcato, aggiungere attivato cellule effettrici di colture di cellule effettrici il target a bersaglio desiderato (E: T) rapporti. Usiamo solitamente E: T ratio a 0.4:1, 1:1, 2:1, 5:1, 10:1, 20:1 e 50:1. </li><li> Aggiungi fresca modificato RPMI 1640 medium (vedi punto 2.5) a 6 pozzi di cellule bersaglio per fungere da controllo lisi spontanea. </li><li> Co-coltura le cellule effettrici e la destinazione di 16 ore. </li><li> Raccogliere il supernatante in tubi 6x50 mm Vetro Lime </li><li> Lisare le cellule con l&#39;aggiunta di 100μl 2% SDS e pipettaggio più volte con delicatezza. </li><li> Raccogliere lisato cellulare in un altro insieme di tubi 6x50 mm Vetro Lime. </li><li> Lavare una volta con i pozzi puliti H 2 O e aggiungere il lavaggio di tubi lisato la cella. </li><li> Contare il supernatanti e lisati cellulari mediante un contatore gamma. </li><li> Calcolare lisi specifica quanto segue: <img src="files/ftp_upload/2724/2724eq1.jpg" alt="Equazione 1" /></li></ol> 4. Colorazione delle cellule per l&#39;imaging cellulare dal vivo Tra le più comunemente utilizzati coloranti potenziale della membrana mitocondriale, TMRM espone la tossicità mitocondriale meno. 3 Perciò, scegliamo TMRM per questi studi dal vivo imaging cellulare. <ol><li> Preparare uno stock 40 mM soluzione TMRM in DMSO e conservare a -20 ° C. Fare una [25 nM] fresca soluzione di lavoro in rosso fenolo senza DMEM con tutti i supplementi per NIT-1 coltura cellulare 1. </li><li> Macchia obiettivo NIT-1 con cellule TMRM 25 nM per 30 min a 37 ° C. </li><li> Sostituire il supporto con mezzi freschi contenente 5 nM TMRM a mantenere la distribuzione di equilibrio del colorante 4. </li><li> Conte attivato cellule T effettrici AI4 utilizzando un hematocytometer. </li><li> Macchia attivato AI4 effettrici delle cellule T con 1 ml / ml per PicoGreen5 minuti a temperatura ambiente e lavare con rosso fenolo senza terreno di coltura per 3 volte. </li></ol> 5. La valutazione dei linfociti T-mediata morte delle cellule beta utilizzando l&#39;imaging cellulare dal vivo <ol><li> Montare il coprioggetti camerati con le cellule NIT colorate sul palco di una Zeiss LSM 510 microscopio confocale. Rimuovere la linguetta con un dremmel e il gas sterilizzare il vetro con ossido di etheline camerati. Il palco è dotato di un live-cellule in camera di imaging che ha temperatura controllata a 37 ° C e 5% di CO 2 con l&#39;umidità. </li><li> Aggiungi attivato e colorate le cellule T per camere designato a diversi E: T ratio. </li><li> Ha aggiunto lo stesso numero di cellule Jurkat colorate alle camere di controllo. </li></ol> 6. Ottenere immagini di cellule vive Il microscopio è dotato di uno stadio motorizzato che ci ha permesso di acquisire le immagini riprese in luoghi diversi dalle camere stesso o diverso automaticamente nel corso del tempo l&#39;esperimento. <ol><li> Utilizza un obiettivo 63x obiettivo di olio, prendete le immagini ad un intervallo di ogni 3 minuti per un totale di 300 fotogrammi al luogo. </li><li> Rileva colorazione TMRM utilizzando una lunghezza d&#39;onda di eccitazione di 543 nm e set di filtri per l&#39;emissione di 565-619 nm </li><li> Rileva colorazione PicoGreen utilizzando una eccitazione 488 nm e un set di filtri per l&#39;emissione di 500-630 nm. Il video è stato creato utilizzando il software LSM Zeiss. </li></ol> 7. Conversione video per la pubblicazione <ol><li> Utilizzando il software LSM Zeiss, creare un file compresso filmato in un formato AVI. </li><li> Per convertire i video nel formato di pubblicazione, importare il video nel pacchetto software FIJI ( <a href="http://pacific.mpi-cbg.de/wiki/index.php/Fiji">http://pacific.mpi-cbg.de/wiki/index.php/Fiji</a> ), un ImageJ ( <a href="http://rsb.info.nih.gov/ij/">http://rsb.info. nih.gov / ij /</a> ) distribuzione, usando il plugin Bioformats da LOCI ( <a href="http://www.loci.wisc.edu/software/bio-formats">http://www.loci.wisc.edu/software/bio-formats</a> ). </li><li> Regolare le impostazioni di luminosità e il contrasto per bilanciare i segnali verde e rosso e il frame rate è stato fissato a 2 fotogrammi / secondo utilizzando il menu opzioni di animazione. </li><li> Ritagliare il video a 512 x 512 pixel ed esportare come un file AVI non compresso. </li><li> Aprire questo file AVI nel software QuickTime 7 (computer Apple, Cupertino, CA) e comprimere e di esportazione nel formato aperto di file video H264/MPEG-4 a 1200 kbs / secondo. </li></ol> 8. Rappresentante dei risultati: <ol><li> Un risultato rappresentativo di 51 test Cr CML. La Figura 1 mostra un risultato rappresentativo di un saggio in cui CML lisi specifiche per cento (asse Y) aumenta con l&#39;Effector: rapporto di destinazione (asse X) aumenta. Cellule bersaglio sono isolotti primarie isolate da immunodeficienti NOD RAG1-/ -. Topi ed etichettato con 51 Cr. Splenociti da topi transgenici NOD.AI4α / β sono isolati e attivata come descritto al punto 2. Obiettivi e effettori sono stati co-coltura per 16 ore. Lisi specifiche per cento è calcolato come descritto al punto 3.11. </li><li> Due rappresentative (positivi e negativi) i risultati di una T cellulo-mediata della membrana delle cellule beta dissipazione mitocondriale potenziali sono presentati. Le cellule sono colorate e le reazioni sono registrate come descritte ai punti 4, 5 e 6 di cui sopra, i file video sono creati come al punto 7. Video 1: La versione beta linea di topi cellule NIT-1 è stato macchiato il potenziale di membrana mitocondriale TMRM colorante (rosso). Attivato, autoreattivi delle cellule T CD8 + AI4 (verde tinto con PicoGreen) sono stati co-coltura con queste NIT-1 le cellule a E: T rapporto di 50:1. NIT-1 potenziale della membrana mitocondriale dissipata gradualmente nel corso di 400 minuti di durata, ma solo nei distretti che sono stati interagendo con le cellule T AI4. Video 2: Come esperimento di controllo, NIT-1 le cellule sono state colorate con TMRM e co-coltura con cellule Jurkat PicoGreen colorate a E: T rapporto di 50:1. Cellule Jurkat sono un essere umano linea di cellule T che è MHC non corrispondenti. NIT-1 le cellule mantenuto il potenziale della membrana mitocondriale per tutta la durata dei 400 minuti di co-incubazione. Cellule Jurkat non hanno interagito con NIT-1 cluster e quindi non provocare l&#39;uccisione. </li></ol><img src="files/ftp_upload/2724/2724fig1.jpg" alt="Figura 1" /> Figura 1 risultato Rappresentante della LMC utilizzando come isolotti cellule bersaglio primario isolate da immunodeficienza NOD.Rag1-/ -. Topi e splenociti da topi transgenici NOD.AI4α / β. Obiettivi e effettori sono stati co-coltura per 16 ore. Lisi per cento specifica aumenta con l&#39;Effector: aumenta il rapporto di destinazione. Video 1. Linea di cellule beta del mouse NIT-1 è stato macchiato il potenziale della membrana mitocondriale TMRM colorante (rosso). Attivato autoreattivi delle cellule T CD8 + AI4 (verde tinto con PicoGreen) sono stati co-coltura con queste NIT-1 le cellule in E: rapporto T di 50:1. NIT-1 potenziale di membrana mitocondriale dissipazioneTed gradualmente nel corso di 400 minuti di durata, ma solo nei distretti che sono stati interagendo con verde AI4 cellule T. <a href="http://www.jove.com/files/ftp_upload/2724/video.mov">Clicca qui per vedere il video</a> . Video 2. NIT-1 le cellule sono state colorate identiche a quelle descritte nel video 1 e co-coltura con PicoGreen macchiata linea di cellule umane Jurkat T. NIT-1 le cellule erano in grado di mantenere il potenziale della membrana mitocondriale pensato la durata di 400 minuti. Cellule Jurkat non hanno interagito con NIT-1 cluster e quindi non provocare l&#39;uccisione. <a href="http://www.jove.com/files/ftp_upload/2724/Video2.mp4">Clicca qui per vedere il video</a> .

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	<li>Hamaguchi, K., Gaskins, H. R., Leiter, E. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NIT-1,+a+pancreatic+beta-cell+line+established+from+a+transgenic+NOD/Lt+mouse.">NIT-1, a pancreatic beta-cell line established from a transgenic NOD/Lt mouse.</a> Diabetes. 40, 842-849 (1991).</li><li>Chen, J., Gusdon, A. M., Piganelli, J., Leiter, E. H., Mathews, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=mt-Nd2a+modifies+resistance+against+autoimmune+Type+1+diabetes+in+NOD+mice+at+the+level+of+the+pancreatic+beta+cell.">mt-Nd2a modifies resistance against autoimmune Type 1 diabetes in NOD mice at the level of the pancreatic beta cell.</a> Diabetes. , (2010).</li><li>Scaduto, R. C., Grotyohann, L. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+mitochondrial+membrane+potential+using+fluorescent+rhodamine+derivatives.">Measurement of mitochondrial membrane potential using fluorescent rhodamine derivatives.</a> Biophys J. 76, 469-477 (1999).</li><li>Lemasters, J. J., Ramshesh, V. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imaging+of+mitochondrial+polarization+and+depolarization+with+cationic+fluorophores.">Imaging of mitochondrial polarization and depolarization with cationic fluorophores.</a> Methods Cell Biol. 80, 283-295 (2007).</li><li>Abel, M., Krokowski, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathophysiology+of+immune-mediated+(type+1)+diabetes+mellitus:+potential+for+immunotherapy.">Pathophysiology of immune-mediated (type 1) diabetes mellitus: potential for immunotherapy.</a> BioDrugs. 15, 291-301 (2001).</li><li>Mathews, C. E., Graser, R. T., Savinov, A., Serreze, D. V., Leiter, E. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unusual+resistance+of+ALR/Lt+mouse+beta+cells+to+autoimmune+destruction:+role+for+beta+cell-expressed+resistance+determinants.">Unusual resistance of ALR/Lt mouse beta cells to autoimmune destruction: role for beta cell-expressed resistance determinants.</a> Proc Natl Acad Sci U S A. , 235-240 (2001).</li><li>Szabadkai, G., Duchen, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondria+mediated+cell+death+in+diabetes.">Mitochondria mediated cell death in diabetes.</a> Apoptosis. 14, 1405-1423 (2009).</li><li>Ly, J. D., Grubb, D. R., Lawen, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mitochondrial+membrane+potential+(deltapsi(m))+in+apoptosis;+an+update.">The mitochondrial membrane potential (deltapsi(m)) in apoptosis; an update.</a> Apoptosis. 8, 115-128 (2003).</li><li>Dudek, N. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytotoxic+T-cells+from+T-cell+receptor+transgenic+NOD8.3+mice+destroy+beta-cells+via+the+perforin+and+Fas+pathways.">Cytotoxic T-cells from T-cell receptor transgenic NOD8.3 mice destroy beta-cells via the perforin and Fas pathways.</a> Diabetes. 55, 2412-2418 (2006).</li><li>Pakala, S. V., Chivetta, M., Kelly, C. B., Katz, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+autoimmune+diabetes+the+transition+from+benign+to+pernicious+insulitis+requires+an+islet+cell+response+to+tumor+necrosis+factor+alpha.">In autoimmune diabetes the transition from benign to pernicious insulitis requires an islet cell response to tumor necrosis factor alpha.</a> J Exp Med. 189, 1053-1062 (1999).</li></ol>

Gli esperimenti sugli animali sono stati eseguiti in conformità con le linee guida e dei regolamenti previsti dalla University of Animal Care Florida e del Comitato Istituzionale Usa.

Cellule T citotossiche mediate la morte delle cellule beta è la fisiopatologia principale di diabete di tipo 1 5. Saggi di CML con 51 rilascio Cr ci permettono di studiare il grado di effettrici bersaglio risposta 6. Tuttavia, il processo dettagliate e percorsi di T mediata dalle cellule morte delle cellule beta non è ancora pienamente compreso. Dal momento che i mitocondri sono fondamentali per la funzione delle cellule beta e la morte 7, ci siamo concentrati sui cambiament...

<table border="1"><tbody><tr><th> Nome del reagente </th><th> Azienda </th><th> Numero di catalogo </th><th> Commenti (opzionale) </th></tr><tr><td> CR-51 </td><td> Perkin Elmer </td><td> NEZ030500IMC </td><td></td></tr><tr><td> PBS </td><td> Cellgro </td><td> 21-040-60 </td><td></td></tr><tr><td> Tetrametil rodamina estere metilico (TMRM) </td><td> Invitrogen </td><td> T668 </td><td></td></tr><tr><td> PicoGreen </td><td> Invitrogen </td><td> P7581 </td><td></td></tr><tr><td> AI4 mimotopo </td><td> mimotopes.com </td><td> aminoacido sequenza: YFIENYLEL </td><td></td></tr><tr><td> IL-2 </td><td> R &amp; S </td><td> 485-MI </td><td></td></tr><tr><td> DMEM </td><td> Invitrogen </td><td> 11885 </td><td></td></tr><tr><td> FBS </td><td> Hyclone </td><td> SH30071.03 </td><td></td></tr><tr><td> Albumina di siero bovino </td><td> Sigma </td><td> A8412 </td><td></td></tr><tr><td> HEPES </td><td> Cellgro </td><td> 25-060-Cl </td><td></td></tr><tr><td> MEM aminoacidi non essenziali </td><td> GIBCO </td><td> 11140 </td><td></td></tr><tr><td> Penicillina / streptomicina </td><td> Gemelli </td><td> 400-109 </td><td></td></tr><tr><td> Rosso fenolo senza DMEM </td><td> Sigma </td><td> D5303 </td><td></td></tr><tr><td> Incubatore CO2 </td><td> Thermo Fisher </td><td> HERAcell 150i </td><td> Mantenuto sterile per colture cellulari </td></tr><tr><td> Cappa di sicurezza biologica </td><td> Thermo Fisher </td><td> Forma 1440 </td><td></td></tr><tr><td> Tubi cultura usa e getta, 6x50 millimetri di vetro Lime </td><td> Pescatore </td><td> 14-958-A </td><td></td></tr><tr><td> Gamma contatore </td><td> Perkin Elmer </td><td> Wizard 1470 Gamma contatore automatico </td><td></td></tr><tr><td> Microscopio confocale </td><td> Zeiss </td><td> Confocale LSM 510 Meta </td><td> Con stadio motorizzato e la camera di cellule vive </td></tr><tr><td> Pipetta (1 ml, 200μl, 20μl, 10μl, 2μl) </td><td> Eppendorf </td><td></td><td></td></tr><tr><td> Tubi (Ambra) </td><td> Pescatore </td><td> 50819772 </td><td></td></tr><tr><td> Centrifuga </td><td> Sorvall Legenda RT + </td><td> 75004377 </td><td></td></tr><tr><td> Emocitometro </td><td> Fisher Scientific </td><td> 267110 </td><td></td></tr><tr><td> Microscopio verticale </td><td> Zeiss </td><td> Axioskop40 </td><td></td></tr><tr><td> NOD.Cg-RAG1 tm1Mom Tg (TcraAI4) 1Dvs/DvsJ Mice </td><td> The Jackson Laboratory </td><td> 004347 </td><td></td></tr><tr><td> NOD.Cg-RAG1 tm1Mom Tg (TcrbAI4) 1Dvs/DvsJ Mice </td><td> The Jackson Laboratory </td><td> 004348 </td><td></td></tr><tr><td> NOD-AI4α / mice β F1 </td><td> N / A </td><td> N / A </td><td> Impianto di animali allevati in UF </td></tr></tbody></table>

methods to assess beta cell death mediated by cytotoxic t lymphocytes

Diabete di tipo 1 (T1D) è una malattia mediata da cellule T autoimmuni. Durante la patogenesi, i pazienti diventano progressivamente più insulinopenic come la produzione di insulina è perso, probabilmente questa è dovuta alla distruzione delle cellule beta pancreatiche da parte delle cellule T. La comprensione dei meccanismi di morte delle cellule beta durante lo sviluppo del diabete di tipo 1 fornirà spunti per generare una cura efficace per questa malattia. Cellulo-mediata linfocitotossicità (LMC), saggi, storicamente, hanno utilizzato il radionuclide cromo 51 (51 Cr) per etichettare le cellule bersaglio. Questi obiettivi sono quindi esposti alle cellule effettrici e il rilascio di 51 Cr da cellule bersaglio viene letto come un&#39;indicazione di mediata dai linfociti morte cellulare. Inibitori di conseguenza la morte cellulare in versione ridotta di 51 Cr. Come cellule effettrici, abbiamo utilizzato un autoreattivi attivati ​​popolazione clonale di CD8 + linfociti T citotossici (CTL) isolato da un topo transgenico magazzino sia per l&#39;alfa e catene beta del recettore AI4 delle cellule T (TCR). AI4 cellule T attivate sono state co-coltura con 51 cellule bersaglio Cr etichettati NIT per 16 ore, il rilascio di 51 Cr è stato registrato per calcolare lisi specifiche Mitocondri partecipare a molti eventi fisiologici importanti, come la produzione di energia, regolazione della trasduzione del segnale, e l&#39;apoptosi. Lo studio delle cellule beta cambia mitocondriale funzionale durante lo sviluppo di diabete di tipo 1 è una zona nuova della ricerca. Utilizzando il potenziale di membrana mitocondriale colorante tetrametile rodamina estere metilico (TMRM) e confocale di immagini microscopiche cellule vive, abbiamo monitorato il potenziale della membrana mitocondriale nel corso del tempo nella linea di cellule beta NIT-1. Per gli studi di imaging, le cellule T effettrici AI4 sono stati etichettati con il colorante fluorescente nucleare colorazione PicoGreen. NIT-1 le cellule e le cellule T sono state co-coltura in chambered coprioggetti e montato sul palco microscopio dotato di una camera di cellule vive, controllata a 37 ° C, con il 5% di CO 2, e umidificata. Durante questi esperimenti immagini sono state prese di ogni cluster ogni 3 minuti per 400 minuti. Più di un corso di 400 minuti, abbiamo osservato la dissipazione del potenziale di membrana mitocondriale in NIT-1 gruppi di cellule in cui sono state allegate AI4 cellule T. Nell&#39;esperimento controllo simultaneo in cui NIT-1 cellule sono state co-coltura con MHC mis-matched cellule umane Jurkat linfociti, potenziale di membrana mitocondriale è rimasto intatto. Questa tecnica può essere usata per osservare in tempo reale i cambiamenti del potenziale di membrana mitocondriale nelle cellule sotto l&#39;attacco dei linfociti citotossici, citochine o altri reagenti citotossici.

Watch this Scientific Journal Video about Methods to Assess Beta Cell Death Mediated by Cytotoxic T Lymphocytes at JoVE.com

Methods to Assess Beta Cell Death Mediated by Cytotoxic T Lymphocytes

Cellulo-mediata linfocitotossicità (LMC) test può essere usato per testare le risposte autoreattivi e lo studio dei meccanismi di morte cellulare in vitro. Tuttavia, utilizzando tecniche confocale live-cell immagini microscopiche con coloranti fluorescenti, il tipo e la cinetica di morte cellulare così come i percorsi utilizzati possono essere studiati in maggiore dettaglio.

Metodi per valutare la morte delle cellule beta Mediata da linfociti T citotossici

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

methods-to-assess-beta-cell-death-mediated-by-cytotoxic-t-lymphocytes

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JoVE Journal

Immunology and Infection

13.3K Views.  University of Florida. Cellulo-mediata linfocitotossicità (LMC) test può essere usato per testare le risposte autoreattivi e lo studio dei meccanismi di morte cellulare in vitro. Tuttavia, utilizzando tecniche confocale live-cell immagini microscopiche con coloranti fluorescenti, il tipo e la cinetica di morte cellulare così come i percorsi utilizzati possono essere studiati in maggiore dettaglio.

Video: Methods to Assess Beta Cell Death Mediated by Cytotoxic T Lymphocytes

Expanding Cytotoxic T Lymphocytes from Umbilical Cord Blood that Target Cytomegalovirus, Epstein-Barr Virus, and Adenovirus

Virus infections after stem cell transplantation are among the most common causes of death, especially after cord blood (CB) transplantation (CBT) where the CB does not contain appreciable numbers of virus-experienced T cells which can protect the recipient from infection.1-4 We and others have shown that virus-specific CTL generated from seropositive donors and infused to the recipient are safe and protective.5-8 However, until recently, virus-specific T cells could not be generated from cord blood, likely due to the absence of virus-specific memory T cells. 
In an effort to better mimic the in vivo priming conditions of na&iuml;ve T cells, we established a method that used CB-derived dendritic cells (DC) transduced with an adenoviral vector (Ad5f35pp65) containing the immunodominant CMV antigen pp65, hence driving T cell specificity towards CMV and adenovirus.9 At initiation, we use these matured DCs as well as CB-derived T cells in the presence of the cytokines IL-7, IL-12, and IL-15.10 At the second stimulation we used EBV-transformed B cells, or EBV-LCL, which express both latent and lytic EBV antigens. Ad5f35pp65-transduced EBV-LCL are used to stimulate the T cells in the presence of IL-15 at the second stimulation. Subsequent stimulations use Ad5f35pp65-transduced EBV-LCL and IL-2. 
From 50x106 CB mononuclear cells we are able to generate upwards of 150 x 106 virus-specific T cells that lyse antigen-pulsed targets and release cytokines in response to antigenic stimulation.11 These cells were manufactured in a GMP-compliant manner using only the 20% fraction of a fractionated cord blood unit and have been translated for clinical use.

Here we describe the first good manufacturing practice (GMP)-compliant method of producing virus-specific cytotoxic T lymphocytes (CTL) from umbilical cord blood, a source of predominantly na&#238;ve T cells.

Espansione linfociti T citotossici da sangue del cordone ombelicale che Target Citomegalovirus, virus di Epstein-Barr virus, e Adenovirus

Virus infections after stem cell transplantation are among the most common causes of death, especially after cord blood (CB) transplantation (CBT) where ...

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Immunologia e infezioni

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

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 a specialized receptor, called the T cell receptor (TCR), which can recognize a specific antigenic peptide bound to HLA class I molecules2. Engagement of infected cells or tumor cells through their HLA class I molecule results in production of lytic molecules such as granzymes and perforin resulting in target cell death. While it is useful to determine frequencies of antigen-specific CD8 T cells using assays such as the ELIspot or flow cytometry, it is also helpful to ascertain the strength of CD8 T cell responses using cytotoxicity assays3. The most recognizable assay for assessing cytotoxic function is the Chromium Release Assay (CRA), which is considered a standard assay 4. The CRA has several limitations, including exposure of cells to gamma radiation, lack of reproducibility, and a requirement for large numbers of cells. Over the past decade, there has been interest in adopting new strategies to overcome these limitations. Newer approaches include those that measure caspase 
release 4, BLT esterase activity 5 and surface expression of CD107 6. The impedance-based assay, using the Roche xCelligence system, was examined in the present paper for its potential as an alternative to the CRA. Impedance or opposition to an electric current occurs when adherent tumor cells bind to electrode plates. Tumor cells detach following killing and electrical impedance is reduced which can be measured by the xCelligence system. The ability to adapt the impedance-based approach to assess cell-mediated killing rests on the observation that T cells do not adhere tightly to most surfaces and do not appear to have much impact on impedance thus diminishing any concern of direct interference of the T cells with the measurement. Results show that the impedance-based assay can detect changes in the levels of antigen-specific cytotoxic CD8 T cells with increased sensitivity relative to the standard CRA. Based on these results, impedance-based approaches may be good alternatives to CRAs or other approaches that aim to measure cytotoxic CD8 T cell functionality.

The chromium release assay, a common assay for detecting cytotoxic T cell activity, has several limitations. Using antigen-specific CD8 T cells and the human breast cancer tumor line, SKBR3, in the present article, an impedance-based approach was examined for the capability of detecting cell killing.

Determinazione ottimale attività citotossica di specifiche cellule T umane Her2neu CD8 confrontando il Cr51 saggio di rilascio al 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 ...

Directed Differentiation of Induced Pluripotent Stem Cells towards T Lymphocytes

Adoptive cell transfer (ACT) of antigen-specific CD8+ cytotoxic T lymphocytes (CTLs) is a promising treatment for a variety of malignancies 1. CTLs can recognize malignant cells by interacting tumor antigens with the T cell receptors (TCR), and release cytotoxins as well as cytokines to kill malignant cells. It is known that less-differentiated and central-memory-like (termed highly reactive) CTLs are the optimal population for ACT-based immunotherapy, because these CTLs have a high proliferative potential, are less prone to apoptosis than more differentiated cells and have a higher ability to respond to homeostatic cytokines 2-7. However, due to difficulties in obtaining a high number of such CTLs from patients, there is an urgent need to find a new approach to generate highly reactive Ag-specific CTLs for successful ACT-based therapies.
TCR transduction of the self-renewable stem cells for immune reconstitution has a therapeutic potential for the treatment of diseases 8-10. However, the approach to obtain embryonic stem cells (ESCs) from patients is not feasible. Although the use of hematopoietic stem cells (HSCs) for therapeutic purposes has been widely applied in clinic 11-13, HSCs have reduced differentiation and proliferative capacities, and HSCs are difficult to expand in in vitro cell culture 14-16. Recent iPS cell technology and the development of an in vitro system for gene delivery are capable of generating iPS cells from patients without any surgical approach. In addition, like ESCs, iPS cells possess indefinite proliferative capacity in vitro, and have been shown to differentiate into hematopoietic cells. Thus, iPS cells have greater potential to be used in ACT-based immunotherapy compared to ESCs or HSCs.
Here, we present methods for the generation of T lymphocytes from iPS cells in vitro, and in vivo programming of antigen-specific CTLs from iPS cells for promoting cancer immune surveillance. Stimulation in vitro with a Notch ligand drives T cell differentiation from iPS cells, and TCR gene transduction results in iPS cells differentiating into antigen-specific T cells in vivo, which prevents tumor growth. Thus, we demonstrate antigen-specific T cell differentiation from iPS cells. Our studies provide a potentially more efficient approach for generating antigen-specific CTLs for ACT-based therapies and facilitate the development of therapeutic strategies for diseases.

Generation of T lymphocytes from induced pluripotent stem (iPS) cells gives an alternative approach of using embryonic stem cells for T cell-based immunotherapy. The method shows that by utilizing either in vitro or in vivo induction system, iPS cells are able to differentiate into both conventional and antigen-specific T lymphocytes.

Differenziazione Regia di cellule staminali pluripotenti indotte verso Linfociti T

Adoptive cell transfer (ACT) of antigen-specific CD8+  cytotoxic T lymphocytes (CTLs) is a promising treatment for a variety of  malignancies 1. CTLs can  ...

Isolation and Th17 Differentiation of Na&iuml;ve CD4 T Lymphocytes

Th17 cells are a distinct subset of T cells that have been found to produce interleukin 17 (IL-17), and differ in function from the other T cell subsets including Th1, Th2, and regulatory T cells. Th17 cells have emerged as a central culprit in overzealous inflammatory immune responses associated with many autoimmune disorders. In this method we purify T lymphocytes from the spleen and lymph nodes of C57BL/6 mice, and stimulate purified CD4+ T cells under control and Th17-inducing environments. The Th17-inducing environment includes stimulation in the presence of anti-CD3 and anti-CD28 antibodies, IL-6, and TGF-&#946;. After incubation for at least 72 hours and for up to five days at 37 &#176;C, cells are subsequently analyzed for the capability to produce IL-17 through flow cytometry, qPCR, and ELISAs. Th17 differentiated CD4+CD25- T cells can be utilized to further elucidate the role that Th17 cells play in the onset and progression of autoimmunity and host defense. Moreover, Th17 differentiation of CD4+CD25- lymphocytes from distinct murine knockout/disease models can contribute to our understanding of cell fate plasticity.

Isolation and Th17 Differentiation of Na&amp;#239;ve CD4 T Lymphocytes

With effector functions distinct from other T cell subsets, Th17 cells have been centrally implicated in inflammatory autoimmunity. This in vitro Th17 differentiation protocol provides a means to determine whether na&#239;ve CD4+ T lymphocytes can differentiate into Th17 cells, and to further examine their role in autoimmunity and host response.

Isolamento e differenziazione di Th17 Naïve linfociti T CD4

Th17 cells are a distinct subset of T cells that have been found to produce interleukin 17 (IL-17), and differ in function from the other T cell subsets ...

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.

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 ...

Radial Mobility and Cytotoxic Function of Retroviral Replicating Vector Transduced, Non-adherent Alloresponsive T Lymphocytes

We report a novel adaptation of the Radial Monolayer Cell Migration assay, first reported to measure the radial migration of adherent tumor cells on extracellular matrix proteins, for measuring the motility of fluorescently-labeled, non-adherent human or murine effector immune cells. This technique employs a stainless steel manifold and 10-well Teflon slide to focally deposit non-adherent T cells into wells prepared with either confluent tumor cell monolayers or extracellular matrix proteins. Light and/or multi-channel fluorescence microscopy is used to track the movement and behavior of the effector cells over time. Fluorescent dyes and/or viral vectors that code for fluorescent transgenes are used to differentially label the cell types for imaging. This method is distinct from similar-type in vitro assays that track horizontal or vertical migration/invasion utilizing slide chambers, agar or transwell plates. The assay allows detailed imaging data to be collected with different cell types distinguished by specific fluorescent markers; even specific subpopulations of cells (i.e., transduced/nontransduced) can be monitored. Surface intensity fluorescence plots are generated using specific fluorescence channels that correspond to the migrating cell type. This allows for better visualization of the non-adherent immune cell mobility at specific times. It is possible to gather evidence of other effector cell functions, such as cytotoxicity or transfer of viral vectors from effector to target cells, as well. Thus, the method allows researchers to microscopically document cell-to-cell interactions of differentially-labeled, non-adherent with adherent cells of various types. Such information may be especially relevant in the assessment of biologically-manipulated or activated immune cell types, where visual proof of functionality is desired with tumor target cells before their use for cancer therapy.

We describe a protocol to monitor radial mobility of non-adherent immune cells in vitro using a cell sedimentation manifold/slide apparatus. Cell migration is tracked on monolayers of tumor cells or on extracellular matrix proteins. Examination by light and fluorescence microscopy allows for observation of cell mobility and cytotoxic functionality.

Radial Mobilità e citotossico Funzione retrovirale Replica vettoriale trasdotte, non aderente Alloresponsive Linfociti T

We report a novel adaptation of the Radial Monolayer Cell Migration assay, first reported to measure the radial migration of adherent tumor cells on ...

Molecular Diffusion in Plasma Membranes of Primary Lymphocytes Measured by Fluorescence Correlation Spectroscopy

Fluorescence correlation spectroscopy (FCS) is a powerful technique for studying the diffusion of molecules within biological membranes with high spatial and temporal resolution. FCS can quantify the molecular concentration and diffusion coefficient of fluorescently labeled molecules in the cell membrane. This technique has the ability to explore the molecular diffusion characteristics of molecules in the plasma membrane of immune cells in steady state (i.e., without processes affecting the result during the actual measurement time). FCS is suitable for studying the diffusion of proteins that are expressed at levels typical for most endogenous proteins. Here, a straightforward and robust method to determine the diffusion rate of cell membrane proteins on primary lymphocytes is demonstrated. An effective way to perform measurements on antibody-stained live cells and commonly occurring observations after acquisition are described. The recent advancements in the development of photo-stable fluorescent dyes can be utilized by conjugating the antibodies of interest to appropriate dyes that do not bleach extensively during the measurements. Additionally, this allows for the detection of slowly diffusing entities, which is a common feature of proteins expressed in cell membranes. The analysis procedure to extract molecular concentration and diffusion parameters from the generated autocorrelation curves is highlighted. In summary, a basic protocol for FCS measurements is provided; it can be followed by immunologists with an understanding of confocal microscopy but with no other previous experience of techniques for measuring dynamic parameters, such as molecular diffusion rates.

A method to measure protein diffusion in membranes of primary immune cells using fluorescence correlation spectroscopy (FCS) is described. In this paper, the use of antibodies for fluorescent labeling is illustrated.

Diffusione molecolare nel plasma membrane dei linfociti primari misurati da Fluorescence Correlation Spectroscopy

Fluorescence correlation spectroscopy (FCS) is a powerful technique for studying the diffusion of molecules within biological membranes with high spatial ...

Rapid Quantification of Mitogen-induced Blastogenesis in T Lymphocytes for Identifying Immunomodulatory Drugs

Lymphocyte proliferation in response to antigenic or mitogenic stimulation is a readily quantifiable phenomenon useful for testing immunomodulatory (i.e., immunosuppressive or immunostimulatory) chemical compounds and biologics. One of the earliest steps during mitogenesis is cell enlargement or blastogenic transformation, whereupon the cell volume increases before division. It is usually detectable in the first several hours of T-lymphocyte stimulation. Here, we describe a rapid method to quantify blastogenesis in T lymphocytes isolated from mouse spleens and human peripheral blood mononuclear cells (PBMCs) using an automated cell counter. Various commonly used proliferation assays for the most part are laborious and only reflect the overall population effect rather than individual cellular effects within a population. In contrast, the presented automated cell counter assay provides rapid, direct, and precise measurements of cell diameters that can be used for assessing the effectiveness of various mitogens and immunomodulatory drugs in vitro.

T-lymphocyte mitogenesis is accompanied by blastogenic transformation, whereupon the cell volume enlarges before cell division. Here, we describe a method to quantify blastogenesis in T lymphocytes using an automated cell counter with the capability of measuring cell diameters.

La quantificazione rapida di Mitogen indotta blastogenesi in linfociti T per l&#39;identificazione farmaci immunomodulatori

Lymphocyte proliferation in response to antigenic or mitogenic stimulation is a readily quantifiable phenomenon useful for testing immunomodulatory (i.e., ...

A Method to Assess Fc-mediated Effector Functions Induced by Influenza Hemagglutinin Specific Antibodies

Antibodies play a crucial role in coupling the innate and adaptive immune responses against viral pathogens through their antigen binding domains and Fc-regions. Here, we describe how to measure the activation of Fc effector functions by monoclonal antibodies targeting the influenza virus hemagglutinin with the use of a genetically engineered Jurkat cell line expressing an activating type 1 Fc-Fc&#947;R. Using this method, the contribution of specific Fc-Fc&#947;R interactions conferred by immunoglobulins can be determined using an in vitro assay.

We describe a method to measure the activation of Fc-mediated effector functions by antibodies that target the influenza virus hemagglutinin. This assay can also be adapted to assess the ability of monoclonal antibodies or polyclonal sera targeting other viral surface glycoproteins to induce Fc-mediated immunity.

Un metodo per valutare le funzioni effettrici Fc-mediata indotte dagli anticorpi specifici di Hemagglutinin di riossidazione

Antibodies play a crucial role in coupling the innate and adaptive immune responses against viral pathogens through their antigen binding domains and ...

Using Terminal Transferase-mediated dUTP Nick End-labelling (TUNEL) and Caspase 3/7 Assays to Measure Epidermal Cell Death in Frogs with Chytridiomycosis

Amphibians are experiencing a great loss in biodiversity globally and one of the major causes is the infectious disease chytridiomycosis. This disease is caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), which infects and disrupts frog epidermis; however, pathological changes have not been explicitly characterized. Apoptosis (programmed cell death) can be used by pathogens to damage host tissue, but can also be a host mechanism of disease resistance for pathogen removal. In this study, we quantify epidermal cell death of infected and uninfected animals using two different assays: terminal transferase-mediated dUTP nick end-labelling (TUNEL), and caspase 3/7. Using ventral, dorsal, and thigh skin tissue in the TUNEL assay, we observe cell death in the epidermal cells in situ of clinically infected animals and compare cell death with uninfected animals using fluorescent microscopy. In order to determine how apoptosis levels in the epidermis change over the course of infection we remove toe-tip samples fortnightly over an 8-week period, and use a caspase 3/7 assay with extracted proteins to quantify activity within the samples. We then correlate caspase 3/7 activity with infection load. The TUNEL assay is useful for localization of cell death in situ, but is expensive and time intensive per sample. The caspase 3/7 assay is efficient for large sample sizes and time course experiments. However, because frog toe tip biopsies are small there is limited extract available for sample standardization via protein quantification methods, such as the Bradford assay. Therefore, we suggest estimating skin surface area through photographic analysis of toe biopsies to avoid consuming extracts during sample standardization.

Using Terminal Transferase-mediated dUTP Nick End-labelling TUNEL and Caspase 3/7 Assays to Measure Epidermal Cell Death in Frogs with Chytridiomycosis

We quantify epidermal cell death in frogs with chytridiomycosis using two methods. First, we use terminal transferase-mediated dUTP nick end-labelling (TUNEL) in situ histology to determine differences between clinically infected and uninfected animals. Second, we conduct a time series analysis of apoptosis over infection using a caspase 3/7 protein analysis.

Utilizzando Terminal transferasi-mediata dUTP Nick End-labelling (TUNEL) e caspasi 3/7 saggi alla morte delle cellule epidermiche di misura in rane con Chytridiomycosis

Amphibians are experiencing a great loss in biodiversity globally and one of the major causes is the infectious disease chytridiomycosis. This disease is ...