Name: a flow cytometry-based cytotoxicity assay for the assessment of human nk cell activity
Uploaded: 2017-08-09T14:00:00
Description: Watch this Scientific Journal Video about A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity at JoVE.com

Vi vil gerne takke Jill Narciso, UCLA Immunogenetics Center, for hendes hjælp med håndskriftet forberedelse.

Samples were collected according to the ethical guidelines established by the UCLA Human Research Protection Program and IRB approved.
1. Preparation of reagents
NOTE: Unless otherwise stated, all reagents should be allowed to equilibrate at room temperature prior to use. All reagents must remain sterile.
<ol>
	<li>Prepare a 2x working solution of Tween-20 (i.e., 0.2%) by adding 10&#160;&#181;L of Tween-20 solution to 5 mL of phosphate-buffered saline (PBS) withou...

<ol>
	<li>Iannello, A., Debbeche, O., Samarani, S., Ahmad, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antiviral+NK+cell+responses+in+HIV+infection:+I.+NK+cell+receptor+genes+as+determinants+of+HIV+resistance+and+progression+to+AIDS.">Antiviral NK cell responses in HIV infection: I. NK cell receptor genes as determinants of HIV resistance and progression to AIDS.</a> J Leukoc Biol. 84 (1), 1-26 (2008).</li><li>Caligiuri, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+natural+killer+cells.">Human natural killer cells.</a> Blood. 112 (3), 461-469 (2008).</li><li>Topham, N. J., Hewitt, E. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+killer+cell+cytotoxicity:+how+do+they+pull+the+trigger?.">Natural killer cell cytotoxicity: how do they pull the trigger?.</a> Immunology. 128 (1), 7-15 (2009).</li><li>Warren, H. S., Smyth, 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=NK+cells+and+apoptosis.">NK cells and apoptosis.</a> Immunol Cell Biol. 77 (1), 64-75 (1999).</li><li>Tognarelli, S., Jacobs, B., Staiger, N., Ullrich, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+Cytometry-based+Assay+for+the+Monitoring+of+NK+Cell+Functions.">Flow Cytometry-based Assay for the Monitoring of NK Cell Functions.</a> J Vis Exp. (116), (2016).</li><li>Somanchi, S. S., McCulley, K. J., Somanchi, A., Chan, L. L., Lee, D. 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+Method+for+Assessment+of+Natural+Killer+Cell+Cytotoxicity+Using+Image+Cytometry.">A Novel Method for Assessment of Natural Killer Cell Cytotoxicity Using Image Cytometry.</a> PLoS One. 10 (10), e0141074 (2015).</li><li>Alter, G., Malenfant, J. M., Altfeld, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD107a+as+a+functional+marker+for+the+identification+of+natural+killer+cell+activity.">CD107a as a functional marker for the identification of natural killer cell activity.</a> J Immunol Methods. 294 (1-2), 15-22 (2004).</li><li>Atkinson, E. A., Gerrard, J. M., Hildes, G. E., Greenberg, A. 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D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+natural+killer+cell+function+by+flow+cytometry.">Determination of natural killer cell function by flow cytometry.</a> Clin Diagn Lab Immunol. 3 (3), 295-300 (1996).</li><li>Jang, Y. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+flow+cytometry-based+natural+killer+cytotoxicity+assay+involving+calcein+AM+staining+of+effector+cells.">An improved flow cytometry-based natural killer cytotoxicity assay involving calcein AM staining of effector cells.</a> Ann Clin Lab Sci. 42 (1), 42-49 (2012).</li><li>Korzeniewski, C., Callewaert, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+enzyme-release+assay+for+natural+cytotoxicity.">An enzyme-release assay for natural cytotoxicity.</a> J Immunol Methods. 64 (3), 313-320 (1983).</li><li>Karimi, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+cytotoxicity+by+bioluminescence+imaging+outperforms+the+standard+chromium-51+release+assay.">Measuring cytotoxicity by bioluminescence imaging outperforms the standard chromium-51 release assay.</a> PLoS One. 9 (2), e89357 (2014).</li><li>Oppenheim, D. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glyco-engineered+anti-EGFR+mAb+elicits+ADCC+by+NK+cells+from+colorectal+cancer+patients+irrespective+of+chemotherapy.">Glyco-engineered anti-EGFR mAb elicits ADCC by NK cells from colorectal cancer patients irrespective of chemotherapy.</a> Br J Cancer. 110 (5), 1221-1227 (2014).</li><li>West, W. H., Cannon, G. B., Kay, H. D., Bonnard, G. D., Herberman, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+cytotoxic+reactivity+of+human+lymphocytes+against+a+myeloid+cell+line:+characterization+of+effector+cells.">Natural cytotoxic reactivity of human lymphocytes against a myeloid cell line: characterization of effector cells.</a> J Immunol. 118 (1), 355-361 (1977).</li><li>Jedema, I., van der Werff, N. M., Barge, R. M., Willemze, R., Falkenburg, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+CFSE-based+assay+to+determine+susceptibility+to+lysis+by+cytotoxic+T+cells+of+leukemic+precursor+cells+within+a+heterogeneous+target+cell+population.">New CFSE-based assay to determine susceptibility to lysis by cytotoxic T cells of leukemic precursor cells within a heterogeneous target cell population.</a> Blood. 103 (7), 2677-2682 (2004).</li><li>Lecoeur, H., Fevrier, M., Garcia, S., Riviere, Y., Gougeon, 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=A+novel+flow+cytometric+assay+for+quantitation+and+multiparametric+characterization+of+cell-mediated+cytotoxicity.">A novel flow cytometric assay for quantitation and multiparametric characterization of cell-mediated cytotoxicity.</a> J Immunol Methods. 253 (1-2), 177-187 (2001).</li><li>Carotta, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeting+NK+Cells+for+Anticancer+Immunotherapy:+Clinical+and+Preclinical+Approaches.">Targeting NK Cells for Anticancer Immunotherapy: Clinical and Preclinical Approaches.</a> Front Immunol. 7, 152 (2016).</li><li>Mandal, A., Viswanathan, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+killer+cells:+In+health+and+disease.">Natural killer cells: In health and disease.</a> Hematol Oncol Stem Cell Ther. 8 (2), 47-55 (2015).</li><li>Rezvani, K., Rouce, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Application+of+Natural+Killer+Cell+Immunotherapy+for+the+Treatment+of+Cancer.">The Application of Natural Killer Cell Immunotherapy for the Treatment of Cancer.</a> Front Immunol. 6, 578 (2015).</li><li>Angelo, L. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Practical+NK+cell+phenotyping+and+variability+in+healthy+adults.">Practical NK cell phenotyping and variability in healthy adults.</a> Immunol Res. 62 (3), 341-356 (2015).</li><li>Zons, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+europium+and+chromium+release+assays:+cytotoxicity+in+healthy+individuals+and+patients+with+cervical+carcinoma.">Comparison of europium and chromium release assays: cytotoxicity in healthy individuals and patients with cervical carcinoma.</a> Clin Diagn Lab Immunol. 4 (2), 202-207 (1997).</li><li>Yovel, G., Shakhar, K., Ben-Eliyahu, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+sex,+menstrual+cycle,+and+oral+contraceptives+on+the+number+and+activity+of+natural+killer+cells.">The effects of sex, menstrual cycle, and oral contraceptives on the number and activity of natural killer cells.</a> Gynecol Oncol. 81 (2), 254-262 (2001).</li><li>Laue, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Altered+NK+cell+function+in+obese+healthy+humans.">Altered NK cell function in obese healthy humans.</a> BMC Obes. 2, 1 (2015).</li><li>Hazeldine, J., Lord, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+ageing+on+natural+killer+cell+function+and+potential+consequences+for+health+in+older+adults.">The impact of ageing on natural killer cell function and potential consequences for health in older adults.</a> Ageing Res Rev. 12 (4), 1069-1078 (2013).</li></ol>

Metoden beskrevet her giver en enkel og omkostningseffektiv alternativ til traditionelle 51Cr release analysen at vurdere NK celle cytotoksisk aktivitet. Denne metode er følsomme, reproducerbare og mindre tidskrævende end tidligere standard metoder, ligesom CRA, og kan bruges til både klinisk og forskning applikationer.
Mens analysen arbejder med både samlede PBMC og beriget NK celler, er mulighed for at bruge PBMC uden behov for at rense cellepopulationer en stor fordel, når d...

Natural killer (NK) celler er en sofistikeret undersæt af menneskets medfødte lymfocytter kritisk involveret i fjernelsen af viralt inficerede celler, transformerede celler og andre patogene trusler 1,2. NK celle lytisk granulat hus cytotoksiske proteiner, såsom perforin og granzymes. Ved aktivering, NK-celler udgør et komplekst samspil med deres mål kendt som immunologiske synapse, hvorved disse cytolytisk molekyler er lokalt frigivet, medførende direkte mål celle lysis og apoptose, sammen med cytokin og chemokine frigivelse og i sidste ende i induktion af en inflammatorisk tilstand 1,3,4.
NK celle aktivering indebærer en kompleks række aktivering og hæmmende interaktioner mellem NK celle receptorer og ligander udtrykkes på overfladen af target-cellerne, danner et stramt reguleret system. En af de mest studerede mekanismer af NK celle aktivering er det "manglende selv". Ja, manglende påvisning af klasse jeg major histocompatibility complex (MHC) eller human leukocyt antigen (HLA) molekyler, på inficeret eller omdannet celler udløser NK celle cytotoksicitet. Tumor og virus-inficerede celler generelt nedregulere disse antigener at undslippe T-celle-medieret immunitet, bliver således primære NK celle mål 1,3,4.
Vurdering af NK cellefunktion er primært kategoriseret i degranulering eller cytotoksicitet assays. Degranulering assays, såsom flow cytometric påvisning af degranulering-associerede markør CD107a, er dog kun vejledende af NK celle aktivering og ikke af deres ultimative funktion, den direkte drab af target celler 5,6,7,8. Derfor, denne begrænsning har tegnet efterforskere til cytotoksicitet assays som et mere sigende og mere direkte alternativ.
Den mangeårige "guldstandarden" for at vurdere celle-mægle cytotoksisk aktivitet af både T og NK celler er chrom release assay (CRA). CRA indebærer radioaktivt mærkning af target-cellerne med 51Cr og co inkubere dem med effektor celler. Denne analyse er gennemsyret af principielt at celle lysis resulterer i frigivelse af protein-bundet 51Cr i supernatanten, der kan måles af gamma optælling. Denne analyse, mens effektiv, er problematisk for en række årsager: høj materialeomkostninger, håndtering og bortskaffelse af radioaktivt 51Cr, spontane frigivelse af 51Cr og vanskelige standardisering - gør det helt upraktisk 9,10.
Siden har udviklet en række ikke-radioaktive assays, der involverer fluorescerende mærkning, enzym udgivelse, og selv bioluminescens, som alternativer til CRA 11,12,13,14. Vi beskriver her en flow flowcytometri-baserede metode til måling af NK celler cytotoksisk aktivitet på K562 target-cellerne som er enkel, følsomme og reproducerbar. K562 celler er en menneskelig erythroleukemic celle linje med reducerede udtryk for HLA klasse I og øget udtryk for ligander til activatory NK receptorer, hvilket gør dem særligt modtagelige for NK celle-medieret cytotoksicitet 15. I denne analyse, K562 celler er forud mærket med carboxyfluorescein diacetat succinimidyl ester (CFSE) og co kulturperler på forskellige nøgletal med enten perifert blod mononukleære celler (PBMC) eller renset NK celler 1. CFSE er en stabil, protein-bindende fluorescerende farvestof, der tillader diskrimination af target-cellerne fra effektor NK celler 16,17. Efter fælles inkubation bruges en nukleinsyre pletten, specielt gennemsyrer membranen af døde celler, til at identificere dræbt target-cellerne (se tabel over materialer). Prøverne er derefter erhvervet på en flow Flowcytometret at bestemme procentdelen af døde (dvs., bejdse +) CFSE + målceller.
Denne analyse kan bruges som en rutinemæssig diagnostisk screening for monogene defekter der påvirker NK celle rum, hvoraf der er ca 30 kendte fejl forårsager enten funktionelt eller klassiske NK celle mangel, og for primær eller sekundær hemophagocytic lymphohistiocytosis. Det er også nyttigt at undersøge NK celleaktivitet hos patienter med tilbagevendende, svær herpes virale infektioner, at evaluere immun rekonstituering efter hæmatopoietisk celle transplantation eller post immunmodulerende behandling 18,19,20, og til et væld af grundlæggende forskning applikationer.

<table>
	<tbody>
		<tr>
			<td>Phosphate-buffered Saline (1x, w/o Ca2+ and Mg2+)</td>
			<td>Corning (Cellgro)</td>
			<td>21-040-CM</td>
			<td></td>
		</tr>
		<tr>
			<td>Ficoll-Paque PLUS</td>
			<td>GE Healthcare</td>
			<td>17-1440-02</td>
			<td></td>
		</tr>
		<tr>
			<td>Tween-20</td>
			<td>Sigma</td>
			<td>BP337-100</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI 1640 Media</td>
			<td>Corning (Cellgro)</td>
			<td>10-040-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Heat-inactivated Fetal Bovine Serum</td>
			<td>Omega Scientific</td>
			<td>FB-02</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin Streptomycin</td>
			<td>Life Technologies</td>
			<td>15140-163</td>
			<td>Stock solution at 10,000 U/mL</td>
		</tr>
		<tr>
			<td>IL-2</td>
			<td>R&#38;D Systems</td>
			<td>202-IL-050</td>
			<td>Lyophilized from a 0.2 &#956;m filtered solution in Acetonitrile and TFA with BSA as a carrier protein. Reconstitute with 500 ul at 100 &#956;g/mL in sterile 100 mM Acetic Acid containing at least 0.1% bovine serum albumin (2.1x10E6 IU/ml)</td>
		</tr>
		<tr>
			<td>K562 Cells</td>
			<td>ATCC</td>
			<td>CCL-243</td>
			<td>Cancer cell line&#160;</td>
		</tr>
		<tr>
			<td>T-75 cell culture flasks</td>
			<td>Corning</td>
			<td>431464</td>
			<td></td>
		</tr>
		<tr>
			<td>CFSE cell proliferation kit</td>
			<td>Life Technologies (CellTrace)</td>
			<td>C34554</td>
			<td>Reconstitute I vial with 18 ul DMSO to prepare a 5mM stock solution. Do not freeze/thaw.</td>
		</tr>
		<tr>
			<td>Sytox Red</td>
			<td>Life Technologies</td>
			<td>S34859</td>
			<td>Stock solution is provided at 5 &#956;M in 1 mL DMSO. The DMSO solution may be subjected to multiple freeze-thaw cycles without reagent degradation.</td>
		</tr>
		<tr>
			<td>Sodium/lithium heparin blood collection tubes</td>
			<td>BD</td>
			<td>02-687-95</td>
			<td></td>
		</tr>
		<tr>
			<td>U-bottom 96-well plate</td>
			<td>Corning</td>
			<td>CLS3897</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipettes</td>
			<td>BD Falcon</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Polystyrene round-bottom tubes (5mL)</td>
			<td>BD Falcon</td>
			<td>14959-5</td>
			<td></td>
		</tr>
		<tr>
			<td>50 mL polypropylene conical tube</td>
			<td>BD Falcon</td>
			<td>352070</td>
			<td></td>
		</tr>
		<tr>
			<td>15 mL polypropylene conical tube</td>
			<td>BD Falcon</td>
			<td>352097</td>
			<td></td>
		</tr>
		<tr>
			<td>Reagent reservoir</td>
			<td>USA Scientific</td>
			<td>2321-2230</td>
			<td></td>
		</tr>
		<tr>
			<td>Human NK cell enrichment cocktail</td>
			<td>StemCell Technologies (RosetteSep)</td>
			<td>15065</td>
			<td></td>
		</tr>
	</tbody>
</table>

a flow cytometry-based cytotoxicity assay for the assessment of human nk cell activity

Inden for det innate immunsystem spille effektor lymfocytter kaldet natural killer (NK) celler en væsentlig rolle i vært forsvar mod afvigende celler, specielt eliminerer tumorsygdomme og viralt inficerede celler. Ca. 30 kendte monogene defekter, sammen med et væld af andre patologiske betingelser forårsage enten funktionelt eller klassiske NK celle mangel, manifesterer i reduceret eller fraværende cytotoksisk aktivitet. Historisk set har været undersøgt cytotoksicitet med radioaktive metoder, som er besværligt, dyrt og potentielt farlige. I denne artikel beskrives en strømlinet, klinisk relevant flow flowcytometri-baserede metode til at kvantificere NK celle cytotoksisk aktivitet. I denne analyse er perifert blod mononukleære celler (PBMC) eller renset NK celle præparater Co rugede på forskellige nøgletal med en target tumor celle linjen kendt for at være følsomme over for NK celle-medieret cytotoksicitet (NKCC). Målcellerne er forud mærket med et fluorescerende farvestof til at tillade deres diskrimination fra effektor celler (NK-celler). Efter inkubationstid, er dræbt target-cellerne identificeret ved en nukleinsyre plet, som specifikt gennemsyrer døde celler. Denne metode er modtagelig for både diagnostik og forskning applikationer og, tak til multi-parameter kapaciteter af flowcytometri, har den ekstra fordel af potentielt giver en dybere analyse af NK celle fænotype og funktion.

Før du konfigurerer analysen, er det stærkt anbefales, at NK celleindholdet vurderes i befolkningens effektor valg. Figur 1 viser en typisk CD56 farvning før (lyseblå) og efter (rød) NK celle berigelse. NK-celler udgør op til 15% af PBMC og bør være mindst 80% ren efter berigelse.
Flow cytometric analyse i denne analyse indebærer påvisning af to parametre: CFSE, påvises i den samme kanal ...

Watch this Scientific Journal Video about A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity at JoVE.com

A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity

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Within the innate immune system, effector lymphocytes known as natural killer (NK) cells play an essential role in host defense against aberrant cells, ...

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NK cell cytotoxicity is a widely used measure to determine the effect of outside intervention on NK cell function. However, the accuracy and ...

Dextran Enhances the Lentiviral Transduction Efficiency of Murine and Human Primary NK Cells

Dextran effektiviserer Lentiviral transduktion af Murine og menneskelige primære NK-celler

The efficient transduction of specific genes into natural killer (NK) cells has been a major challenge. Successful transductions are critical to defining ...

Generation of Knock-out Primary and Expanded Human NK Cells Using Cas9 Ribonucleoproteins

Generation af Knock-out primære og udvidet menneskelige NK celler ved hjælp af Cas9 Ribonucleoproteins

CRISPR/Cas9 technology is accelerating genome engineering in many cell types, but so far, gene delivery and stable gene modification have been challenging ...