Name: genome engineering of primary human b cells using crispr/cas9
Uploaded: 2020-11-03T14:00:00
Description: Watch this Scientific Journal Video about Genome Engineering of Primary Human B Cells Using CRISPR/Cas9 at JoVE.com

Dette arbeidet ble finansiert av Children's Cancer Research Fund (CCRF) og NIH R01 AI146009 til B.S.M.

Leukafereseprøver fra friske donorer ble hentet fra en lokal blodbank. Alle eksperimenter beskrevet her ble fastslått å være unntatt for forskning av Institutional Review Board (IRB) og ble godkjent av Institutional Biosafety Committee (IBC) ved University of Minnesota.
MERK: Alle eksperimenter ble utført i samsvar med den universelle forholdsregelen for blodbårne patogener, med sterile/aseptiske teknikker og riktig biosikkerhetsnivå-2-utstyr.
1. Forbered kostt...

<ol>
	<li>LeBien, T. W., Thomas, T. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=B+lymphocytes:+how+they+develop+and+function.">B lymphocytes: how they develop and function.</a> Blood. 112 (5), 1570-1580 (2008).</li><li>Nutt, S. L., Hodgkin, P. D., Tarlinton, D. M., Corcoran, L. 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+generation+of+antibody-secreting+plasma+cells.">The generation of antibody-secreting plasma cells.</a> Nature Reviews Immunology. 15, 160-171 (2015).</li><li>Slifka, M. K., Antia, R., Whitmire, J. K., Ahmed, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Humoral+immunity+due+to+long-lived+plasma+cells.">Humoral immunity due to long-lived plasma cells.</a> Immunity. 8 (3), 363-372 (1998).</li><li>Spriggs, M. K., 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=Recombinant+human+CD40+ligand+stimulates+B+cell+proliferation+and+immunoglobulin+E+secretion.">Recombinant human CD40 ligand stimulates B cell proliferation and immunoglobulin E secretion.</a> Journal of Experimental Medicines. 176 (6), 1543-1550 (1992).</li><li>Fusil, F., 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=A+lentiviral+vector+allowing+physiologically+regulated+membrane-anchored+and+secreted+antibody+expression+depending+on+B-cell+maturation+status.">A lentiviral vector allowing physiologically regulated membrane-anchored and secreted antibody expression depending on B-cell maturation status.</a> Molecular Therapy. 23 (11), 1734-1747 (2015).</li><li>Luo, X. M., 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=Engineering+human+hematopoietic+stem/progenitor+cells+to+produce+a+broadly+neutralizing+anti-HIV+antibody+after+in+vitro+maturation+to+human+B+lymphocytes.">Engineering human hematopoietic stem/progenitor cells to produce a broadly neutralizing anti-HIV antibody after in vitro maturation to human B lymphocytes.</a> Blood. 113 (7), 1422-1431 (2008).</li><li>Mock, U., Thiele, R., Uhde, A., Fehse, B., Horn, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+lentiviral+transduction+and+transgene+expression+in+primary+human+B+cells.">Efficient lentiviral transduction and transgene expression in primary human B cells.</a> Human Gene Therapy Methods. 23 (6), 408-415 (2012).</li><li>Heltemes-Harris, L. M., 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=Sleeping+Beauty+transposon+screen+identifies+signaling+modules+that+cooperate+with+STAT5+activation+to+induce+B-cell+acute+lymphoblastic+leukemia.">Sleeping Beauty transposon screen identifies signaling modules that cooperate with STAT5 activation to induce B-cell acute lymphoblastic leukemia.</a> Oncogene. 35 (26), 3454-3464 (2016).</li><li>Johnson, M. J., Laoharawee, K., Lahr, W. S., Webber, B. R., Moriarity, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+of+primary+human+B+cells+with+CRISPR/Cas9+targeted+nuclease.">Engineering of primary human B cells with CRISPR/Cas9 targeted nuclease.</a> Scientific Reports. 8, 12144 (2018).</li><li>Hung, K. L., 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=Engineering+protein-secreting+plasma+cells+by+homology-directed+repair+in+primary+human+B+cells.">Engineering protein-secreting plasma cells by homology-directed repair in primary human B cells.</a> Molecular Therapy. 26 (2), 456-467 (2018).</li><li>Cui, Y., Xu, J., Cheng, M., Liao, X., Peng, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review+of+CRISPR/Cas9+sgRNA+design+tools.">Review of CRISPR/Cas9 sgRNA design tools.</a> Interdisciplinary Sciences. 10 (2), 455-465 (2018).</li><li>Rees, H. A., Liu, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Base+editing:+precision+chemistry+on+the+genome+and+transcriptome+of+living+cells.">Base editing: precision chemistry on the genome and transcriptome of living cells.</a> Nature Reviews Genetics. 19 (12), 770-788 (2018).</li><li>Spiegel, A., Bachmann, M., Jurado Jim&#233;nez, G., Sarov, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CRISPR/Cas9-based+knockout+pipeline+for+reverse+genetics+in+mammalian+cell+culture.">CRISPR/Cas9-based knockout pipeline for reverse genetics in mammalian cell culture.</a> Methods. 164-165, 49-58 (2019).</li><li>Suzuki, T., Kazuki, Y., Oshimura, M., Hara, T. <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+system+for+simultaneous+or+sequential+integration+of+multiple+gene-loading+vectors+into+a+defined+site+of+a+human+artificial+chromosome.">A novel system for simultaneous or sequential integration of multiple gene-loading vectors into a defined site of a human artificial chromosome.</a> PLoS One. 9, 110404 (2014).</li><li>Bak, R. O., Porteus, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CRISPR-mediated+integration+of+large+gene+cassettes+using+AAV+donor+vectors.">CRISPR-mediated integration of large gene cassettes using AAV donor vectors.</a> Cell Reports. 20 (3), 750-756 (2017).</li><li>Shirley, J. L., de Jong, Y. P., Terhorst, C., Herzog, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immune+responses+to+viral+gene+therapy+vectors.">Immune responses to viral gene therapy vectors.</a> Molecular Therapy. 28 (3), 709-722 (2020).</li><li>Martino, A. T., Markusic, 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=Immune+response+mechanisms+against+AAV+vectors+in+animal+models.">Immune response mechanisms against AAV vectors in animal models.</a> Molecular Therapy - Methods and Clinical Development. 17, 198-208 (2020).</li></ol>

Presis genomteknikk i primære humane B-celler har vært utfordrende inntil nylig9,10. Vi hadde tidligere publisert protokoller ved hjelp av CRISPR/Cas9 for å konstruere primære menneskelige B-celler9. Her skisserer vi forbedrede protokoller for B-celleisolasjon, utvidelse og ingeniørarbeid for å muliggjøre effektiv KO av CD19 eller for knocking-in EGFP.
Her viser vi at vår ekspansjonsprotokoll ti...

B-celler er en undergruppe av lymfocyttlinjen avledet fra hematopoietiske stamceller. De utfører en kritisk rolle i det adaptive humorale immunforsvaret ved å produsere store mengder antistoffer som svar på immunutfordringer1. B-celler er også forløpere til minne B-celler og de terminalt differensierte, langlivede plasmacellene, og gir dermed varig humoristisk immunitet2. Spesielt plasmaceller er unike blant immunceller i deres evne til å produsere store mengder av et bestemt antistoff mens de overlever i år eller tiår3. I tillegg gjør enkel isolasjon fra perifert blod B-cellelinjen til en utmerket kandidat for nye cellebaserte terapier4.
Tidligere har tilfeldige integrasjonsmetoder, for eksempel de som bruker lentivirale vektorer eller en Sleeping Beauty-transposon, blitt brukt til å konstruere B-celler for transgene levering og uttrykk5,6, 7,8. Imidlertid gjør den ikke-spesifikke karakteren av disse tilnærmingene det vanskelig å studere de biologiske funksjonene til et bestemt gen i B-cellene og bærer en iboende risiko for innsetting av mutagenese og variabel transgene uttrykk og / eller silencing i terapeutisk setting.
CRISPR/Cas9-systemet er et kraftig genomteknikkverktøy som gjør det mulig for forskere å redigere genomet til ulike celler nøyaktig i mange arter. Nylig har to grupper, inkludert våre egne, vellykket utviklet metoder for ex vivo-utvidelse og målrettet genomteknikk av primære menneskelige B-celler9,10. Vi vil beskrive prosessen med å rense primære humane B-celler fra en leukaforeseprøve. Etter det vil vi beskrive vår oppdaterte protokoll for B-celleutvidelse og aktivering av isolerte B-celler. Vi vil deretter beskrive en prosess for å slå ut klyngen av differensiering 19 (CD19), en spesifikk B-cellereseptor og et kjennetegn på B-celler, ved elektroporasjon for å introdusere CRISPR / Cas9 mRNA sammen med CD19 sgRNA i aktiverte B-celler.
Cas9 mRNA blir oversatt og binder seg til CD19 sgRNA for å danne et CRISPR/Cas9-sgRNA ribonucleoproteinkompleks (RNP). Deretter fører sgRNA i komplekset Cas9 til å skape dobbeltstrengsbrudd (DSB) ved målsekvensen på exon 2 av genet. Cellene vil reparere DSB ved "ikke-homolog slutt sammenføyning" ved å introdusere eller slette nukleotider, noe som fører til framehift mutasjon og forårsaker at genet blir slått ut. Vi vil deretter måle tapet av CD19 ved strømningscytometri og analysere indeldannelse ved sporing av indels ved dekomponering (TIDE) analyse.
Vi vil deretter beskrive prosessen med å bruke CRISPR/Cas9 sammen med en rekombinant AAV6-vektor (rAAV6, en donormal for homologistyrt reparasjon (HDR)) for å formidle stedsspesifikk innsetting av forbedret grønt fluorescerende protein(EGFP) på det adeno-tilknyttede virusintegrasjonsstedet 1 (AAVS1) genet. AAVS1-genet er et aktivt locus uten kjente biologiske funksjoner og et AAV viralt integrasjonssted på det menneskelige genom; Derfor regnes det som en "trygg havn" for genomteknikk. Her rapporterer vi at utvidelse og aktivering av B-celler tillot opptil 44 ganger ekspansjon på 7 dager med kultur (figur 1). Elektroporasjon av B-celler viste en liten reduksjon av den totale cellehelsen (figur 2A) ved 24 timers ettertransfeksjon. Scatter-plottanalysen av CD19-merket (figur 2B) viste opptil 83 % reduksjon i de redigerte cellene (figur 2C).
TIDE-analysen av kromatografiene (figur 3A) viste at % indels var lik % proteintap ved strømningscytometri (figur 3B). Flowcytometrianalyse av KI-eksperimentet viste at cellene som fikk AAV-vektor (figur 4), sammen med RNP, uttrykte opptil 64% EGFP-positive celler (figur 5A) og senere viste vellykket integrasjon ved knutepunktpolymerasekjedereaksjon (PCR) (Figur 5B). Celleantall viste at alle prøver raskt ble gjenopprettet innen 3 dager etter teknikk (Figur 5C).

<table>
	<tbody>
		<tr>
			<td>Alt-R S.p. Cas9 Nuclease V3 protein, 500 ug</td>
			<td>IDT</td>
			<td>1081059</td>
			<td>smaller size is also available</td>
		</tr>
		<tr>
			<td>Amaxa P3 primary cell 4D- Nucleofector X Kit S (32 RCT)</td>
			<td>Lonza</td>
			<td>V4XP-3032</td>
			<td></td>
		</tr>
		<tr>
			<td>Ammonium-chloride-potassium (ACK) lysing buffer</td>
			<td>Quality Biological</td>
			<td>118-156-101</td>
			<td></td>
		</tr>
		<tr>
			<td>CleanCap chemically modified Cas9 mRNA</td>
			<td>Trilink Biotechnology</td>
			<td>L-7206-1000</td>
			<td></td>
		</tr>
		<tr>
			<td>CpG ODN 2006 (ODN 7909) 5 mg</td>
			<td>Invivogen</td>
			<td>TLRL-2006-5</td>
			<td>different sizes available</td>
		</tr>
		<tr>
			<td>Cryostor CS10, 100 mL</td>
			<td>STEMCELL Technology</td>
			<td>7930</td>
			<td></td>
		</tr>
		<tr>
			<td>CTS Immune Cell SR</td>
			<td>Thermo Fisher Scientific</td>
			<td>A2596101</td>
			<td></td>
		</tr>
		<tr>
			<td>EasySep human B cells isolation kit</td>
			<td>STEMCELL Technology</td>
			<td>17954</td>
			<td></td>
		</tr>
		<tr>
			<td>eBioscience fixable viability dye eFlour 780</td>
			<td>eBiosciences</td>
			<td>65-0865-14</td>
			<td></td>
		</tr>
		<tr>
			<td>Excellerate B cell media, Xeno-free</td>
			<td>R&#38;D Systems</td>
			<td>CCM031</td>
			<td>B-cell basal medium</td>
		</tr>
		<tr>
			<td>Falcon 14 mL Polypropylene Round-bottom Tube</td>
			<td>Corning</td>
			<td>352059</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>R&#38;D Systems</td>
			<td>S11550</td>
			<td>For thawing B cells only</td>
		</tr>
		<tr>
			<td>Ficoll-Paque Plus</td>
			<td>GE Healthcare</td>
			<td>17-1440-03</td>
			<td></td>
		</tr>
		<tr>
			<td>GeneMate SnapStrip&#174; 8-Strip 0.2 mL PCR Tubes with Individual Attached Dome Caps</td>
			<td>BioExpress</td>
			<td>T-3035-1 / 490003-692</td>
			<td></td>
		</tr>
		<tr>
			<td>Hyclone 0.0067M PBS (No Ca, No Mg) or 1x PBS</td>
			<td>GE lifesciences</td>
			<td>SH30256.01</td>
			<td></td>
		</tr>
		<tr>
			<td>Lonza 4D Nucleofector core unit</td>
			<td>Lonza</td>
			<td>AAF-1002B</td>
			<td></td>
		</tr>
		<tr>
			<td>Lonza 4D Nucleofector X unit</td>
			<td>Lonza</td>
			<td>AAF-1002X</td>
			<td></td>
		</tr>
		<tr>
			<td>Mega CD40 Ligand</td>
			<td>Enzo Life Sciences</td>
			<td>ALX-522-110-C010</td>
			<td></td>
		</tr>
		<tr>
			<td>Mr. Frosty</td>
			<td>Sigma-Aldrich</td>
			<td>C1562-1EA</td>
			<td>For freezing cells</td>
		</tr>
		<tr>
			<td>Pen/Strep 100X</td>
			<td>Sigma-Aldrich</td>
			<td>TMS-AB2-C</td>
			<td></td>
		</tr>
		<tr>
			<td>PerCP anti-human CD19 clone HIB19</td>
			<td>biolegend</td>
			<td>302228</td>
			<td>smaller size is also available</td>
		</tr>
		<tr>
			<td>rAAV6 SA-GFP pakaging ( with our SA-GFP cassette see Figure 4.)</td>
			<td>Vigene Biosciences</td>
			<td>N/A</td>
			<td>large scale packaging, 1e13 GC/mL, 500 mL</td>
		</tr>
		<tr>
			<td>Recombinant human IL-10 protein 250 ug</td>
			<td>R&#38;D Systems</td>
			<td>217-IL-250</td>
			<td>different sizes available</td>
		</tr>
		<tr>
			<td>Recombinant human IL-15 protein 25 ug</td>
			<td>R&#38;D Systems</td>
			<td>247-ILB-025</td>
			<td>different sizes available</td>
		</tr>
		<tr>
			<td>The Big Easy EasySep Magnet</td>
			<td>STEMCELL Technology</td>
			<td>18001</td>
			<td>different sizes available</td>
		</tr>
		<tr>
			<td>Tris-EDTA (TE) buffer</td>
			<td>Fisher Scientific</td>
			<td>BP2476100</td>
			<td></td>
		</tr>
	</tbody>
</table>

genome engineering of primary human b cells using crispr/cas9

B-celler er lymfocytter avledet fra hematopoietiske stamceller og er en nøkkelkomponent i humoralarmen til det adaptive immunsystemet. De gjør attraktive kandidater til cellebaserte terapier på grunn av deres enkle isolasjon fra perifert blod, deres evne til å utvide in vitro og deres levetid in vivo. I tillegg kan deres normale biologiske funksjon – for å produsere store mengder antistoffer – brukes til å uttrykke svært store mengder terapeutisk protein, for eksempel et rekombinant antistoff for å bekjempe infeksjon, eller et enzymopatier. Her gir vi detaljerte metoder for å isolere primære menneskelige B-celler fra perifere blodmonynukleære celler (PBMCer) og aktivere / utvide isolerte B-celler in vitro. Deretter demonstrerer vi trinnene som er involvert i bruk av CRISPR/Cas9-systemet for stedsspesifikk KO av endogene gener i B-celler. Denne metoden muliggjør effektiv KO av ulike gener, som kan brukes til å studere de biologiske funksjonene til gener av interesse. Vi demonstrerer deretter trinnene for bruk av CRISPR/Cas9-systemet sammen med en rekombinant, adeno-assosiert, viral (rAAV) vektor for effektiv stedsspesifikk integrasjon av en transgene uttrykkskassett i B-celler. Sammen gir denne protokollen en trinnvis ingeniørplattform som kan brukes i primære menneskelige B-celler for å studere biologiske funksjoner av gener så vel som for utvikling av B-celleterapeutikk.

Den oppdaterte utvidelses- og aktiveringsprotokollen gjorde det mulig å utvide B-celler raskt på opptil 44 ganger på 7 dager (Figur 1; n =3 givere). I KO-eksperimentet viste B-celleantallet ved hjelp av Trypan blå farging mer enn 80% levedyktige celler med en liten reduksjon i cellegjenoppretting i både kontrollen og CD19 KO-prøvene ved 24 timers post-elektroporasjon (Figur 2A; p ≥ 0,05, n = 3 donorer). Dette resultatet indikerer at elektroporasjon påvi...

Watch this Scientific Journal Video about Genome Engineering of Primary Human B Cells Using CRISPR/Cas9 at JoVE.com

Genome Engineering of Primary Human B Cells Using CRISPR/Cas9

Her tilbyr vi en detaljert, trinnvis protokoll for CRISPR/Cas9-basert genomteknikk av primære humane B-celler for genutslag (KO) og knock-in (KI) for å studere biologiske funksjoner av gener i B-celler og utvikling av B-celleterapeutikk.

Genomteknikk av primære humane B-celler ved hjelp av CRISPR/Cas9

B cells are lymphocytes derived from hematopoietic stem cells and are a key component of the humoral arm of the adaptive immune system. They make ...

This protocol allows researchers to precisely eliminate a gene in B cells to study the loss of function effects of that gene or to insert a trans gene for stable trans gene expression that can be used for research or therapeutic purposes. The main advantage of this method is that it provides a universal platform that makes it possible to easily and precisely engineer B cells with high efficiencies. This method can be used to engineer B cells to express recombinant antibodies or enzymes and then transfer those B cells to treat infections or in enzymopathies.To begin, thaw B cells in a 37 degree Celsius water bath. While waiting, transfer two milliliters of pre warmed FBS into a sterile, 15-milliliter conical tube. Once the B cells are completely thawed, immediately add one milliliter of pre-warmed FBS, drop-wise, into the sample.Incubate at room temperature for one minute. Gently pipette to resuspend the sample and transfer the whole volume, drop-wise, into a conical tube containing two milliliters of prewarmed FBS. Bring the volume to 15 milliliters with sterile PBS, then cap the tube and invert it gently two to three times.Centrifuge the sample at 400 times G for five minutes, then discard the supernatant without disturbing the cell pellet. Resuspend the pellet with one milliliter of pre-equilibrated B-cell expansion medium and count the cells. The total cell number should be approximately 10 to the seventh cells.Transfer the cells into a flask containing 20 milliliters of the pre-equilibrated B-cell expansion medium. The final concentration of the cells, should be approximately five times 10 to the fifth cells per milliliter. Incubate the flask vertically in a tissue culture incubator.Prepare the CRISPR/Cas9 transfecting substrate by mixing one microgram of chemically modified sgRNA with 1.5 micrograms of chemically modified streptococcus pyogenes Cas9 nucleus mRNA per transfection reaction. For control, add one microliter of TE buffer, instead of sgRNA, into a 0.2-milliliter tube of an eight tube strip. Turn on an electroporator and prepare the nuclear infection reagents.Count and transfer 1 million B cells per transfection reaction, into a sterile conical tube. Bring the volume to 15 milliliters with sterile PBS and centrifuge at 400 times G for five minutes. After centrifugation, discard the supernatant.Resuspend the cells with 10 milliliters of sterile PBS and centrifuge at 400 times G for five minutes, then discard the supernatant completely without disturbing the cell pellet. Add 0.5 micrograms of chemically modified GFP mRNA per 1 million B cells to the cell pellet. Resuspend the pellet with 20 microliters of primary cell transfection reagent per 1 million B cells and mix gently by pipetting five to six times.Transfer 20.5 microliters per transfection reaction into the 0.2-milliliter tubes containing CRISPR/Cas9 reagent. Pipette up and down once to mix and transfer the entire volume into a transfection cuvette. Cap and tap the cuvette on the bench gently to ensure that the liquid covers the bottom of the cuvette.Use the human primary B-cell protocol on the electroporator for transfection. Rest the electroporated cells in the cuvette at room temperature for 15 minutes. Then transfer 80 microliters of the pre-equilibrated B-cell expansion medium into the transfection reaction in the cuvette.Place the cuvette in the tissue culture incubator for 30 minutes. Gently pipe head a couple of times to mix and transfer the whole volume of the sample from the cuvette to an appropriate well of a 48-well tissue culture plate containing one milliliter of the B-cell expansion medium. The final concentration of the cells should be 1 million cells per milliliter.Performing a gene knock-in experiment, transfer recombinant adeno associated type-six viral vector at 500, 000 multiplicity of infection into the appropriate well containing electroporated cells. Place the plate in a tissue culture incubator at 37 degrees Celsius and 5%carbon dioxide with humidity. In the knockout experiment, the B-cell count showed more than 80%viable cells with a slight reduction in cell recovery in both the control and the CD19 knockout samples at 24 hours post electroporation.B cells were collected on day five post-transfection for flow cytometry and tide analysis. Representative scatterplots of the control and knockout samples showed 14 and 95%CD19 negative cells respectively, demonstrating a significant reduction in CD19 expression in the knockout samples. Chromatograms of genomic sequencing showed double peaks in the CD19 knockout B cells, indicating insertions or deletions of nucleotides post-CRISPR/Cas9 mediated double-stranded breaks.Indel analysis of the chromatographs of the knockout samples showed a high percent of indel formation at the CD19 locus, which is consistent with percent CD19 protein loss detected by flow cytometry. B cells from the knock-in experiment were collected on day 12, post engineering. Scatterplots showed 64%of EGFP positive cells in the sample that received the recombinant adeno associated type-six viral vector, together with RNP, whereas none or minimal EGFP positivity was observed in the control and vector-only samples respectively.A junction PCR amplification, showed 1.5 kilobase pair amplicons in the knock-in sample and no PCR product was observed in either the control or vector-only sample. Cell counts showed that the engineering process affects cell recovery in the knock-in sample more than the control or the vector-only samples. However, all samples quickly rebounded within three days after engineering.This procedure can also be used to introduce base editor agents to alter single base pairs in order to induce or correct single point mutations in the B-cell genome. It could also be used to introduce premature stop codons or to alter splice sites, allowing for multiple gene knockouts without the risk of chromosomal translocations. Before this technique was developed, engineering human B cells would inquire the use of other more challenging gene engineering approaches.This technique is an easier, less expensive and quicker alternative. It could also potentially be used to synthesize cell therapy products for clinical use.

Research

JoVE Journal

Biology

Gross and Fine Dissection of Inner Ear Sensory Epithelia in Adult Zebrafish (Danio rerio)

Gross and Fine Dissection of Inner Ear Sensory Epithelia in Adult Zebrafish Danio rerio

Neurosensory epithelia in the inner ear are the crucial structures for hearing and balance functions. Therefore, it is important to understand the ...

Generation of Human CD40-activated B cells

CD40-activated B cells (CD40-B cells) have been identified as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cancer ...

Na&iuml;ve Adult Stem Cells Isolation from Primary Human Fibroblast Cultures

Na&#239;ve Adult Stem Cells Isolation from Primary Human Fibroblast Cultures

Naive Adult Stem Cells Isolasjon fra primære humane fibroblastkulturer

Over the last decade, several adult stem cell  populations have been identified in human skin 1-4.  The isolation of multipotent adult dermal precursors ...

Mouse Genome Engineering Using Designer Nucleases

Mouse Genome Engineering Bruke Designer nukleaser

Transgenic mice carrying site-specific genome modifications (knockout, knock-in) are of vital importance for dissecting complex biological systems as well ...

Generation of Genomic Deletions in Mammalian Cell Lines via CRISPR/Cas9

Generasjon av Genomiske slettinger i pattedyrcellelinjer via CRISPR / Cas9

The prokaryotic clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) 9 system may be re-purposed for site-specific ...

Whole Cell Electrophysiology of Primary Cultured Murine Enterochromaffin Cells

Hele cellen elektrofysiologi primære kulturperler Murine Enterochromaffin celler

Enterochromaffin (EC) cells in the gastrointestinal (GI) epithelium constitute the largest subpopulation of enteroendocrine cells. As specialized sensory ...

Silencing the Spark: CRISPR/Cas9 Genome Editing in Weakly Electric Fish

Deaktivere spark: CRISPR/Cas9 Genova redigere i svakt Electric Fish

Electroreception and electrogenesis have changed in the evolutionary history of vertebrates. There is a striking degree of convergence in these ...

Preparing and Injecting Embryos of Culex Mosquitoes to Generate Null Mutations using CRISPR/Cas9

Preparing and Injecting Embryos of Culex Mosquitoes to Generate Null Mutations using CRISPR/Cas9

Forberede og injisere embryoer av Culex mygg for å generere nullmutasjoner ved hjelp av CRISPR / Cas9

Culex mosquitoes are the major vectors of several diseases that negatively impact human and animal health including West Nile virus and diseases caused by ...

Construction of Homozygous Mutants of Migratory Locust Using CRISPR/Cas9 Technology

Konstruksjon av homozygote mutanter av migrerende gresshopper ved bruk av CRISPR/Cas9-teknologi

The migratory locust, Locusta migratoria, is not only one of the worldwide plague locusts that caused huge economic losses to human beings but also an ...