Die Prostata-Zelllinien werden freundlicherweise von Dr. Ling-Yu Wang und Dr. Hsing-Jien Kung bei Cancer Center, UC Davis zur Verfügung gestellt. Dieses Projekt wird von NIH Galvanotaxis Zuschuss 4R33AI080604 unterstützt.

1. Die Kultivierung Prostatazellen <ol><li> Kultur die PRNs-1-1 und PNT2 Prostata-Zellen auf 100 mm Kulturschalen in RPMI 1640 Medium mit 10% FBS und Antibiotika-Antimykotische ergänzt bei 37 ° C mit 5% CO 2. Aktualisieren Sie das Kulturmedium täglich, bis die Zellen bis zu 80% Konfluenz für die Galvanotaxis Experimente. </li></ol> 2. Montage Galvanotaxis Chambers <ol><li> Montage Unterkammern <ol><li> Wischen eines Kunststoff Galvanotaxis Kammer mit 2-Propanol. Übernehmen Sie die Meeressilizium Versiegelung rund um die kreisförmigen Öffnungen an der Unterseite einer Kammer mit einer Spritze und legen einen großen Deckglas (Abbildung 1). Verwenden Sie die Rückseite eines Baumwoll-Applikator, um das Deckglas nach unten drücken, und wischen Sie das überschüssige Kleber mit Wattestäbchen. Die kreisförmigen Öffnungen kann das Medium und elektrischer Strom über die Zellen zwischen den beiden inneren Medienspeicher zu fließen. </li><li> Schneiden Sie ein kleines Deckglas 6 mm x 2 machen5 mm Abstandshalter mit einer Diamantspitze Marker. </li><li> Drehen Sie die Kammer. Auftragen von 2 Streifen aus dem Silikonkleber mit einer Spritze und / oder einem Metallspatel um eine 10 mm x 25 mm Kanaloberfläche für die Zellanheftung zwischen den kreisförmigen Öffnungen 2 an der unteren Glas erstellen. Kleben Sie zwei Stücke aus Glas Abstandhalter zwischen den zwei kreisförmigen Öffnungen. Benutzen Sie die Rückseite der Watte sich die Abstandshalter zu schieben und wischen Sie das überschüssige Kleber mit Wattestäbchen und / oder Zahnstocher. </li><li> Trocknen Sie die Kammer für 24 Stunden, bis die Silikonkleber ausgehärtet wird. Weichen Sie die Kammer mit destilliertem Wasser über Nacht, um die Essigsäure Rückstand aus der Kleber zu entfernen. Trocknen Sie die Kammer für den sofortigen Einsatz, oder die Kammer für eine spätere Verwendung gespeichert werden in einem sauberen Behälter. <img alt="Figur 1" fo:content-width="5in" src="/files/ftp_upload/51973/51973fig1highres.jpg" width="500" /> Abbildung 1: Montage des unteren Galvanotaxis Kammer. A) Eine große Deckglas wird auf den Boden eines Reinraums. B beigefügt) TWO Glasstücke Abstandshalter werden zwischen den kreisförmigen Öffnungen 2 verklebt, um eine 10 mm x 25 mm Kanal für Zellen zu befestigen erstellen. </li></ol></li><li> Seeding Zellen auf den Galvanotaxis Kammern <ol><li> Bereiten Sie die Anzahl der benötigen Galvanotaxis Kammern für das Experiment benötigt. Jede Zelllinie oder Behandlung erfordert einen einzelnen Galvanotaxis Kammer. Wischen Sie die Galvanotaxis Kammern mit 2-Propanol. Waschen Sie die Kammern mit sterilem PBS 3 mal und überprüfen Sie den Flüssigkeitsstrom zwischen den zwei kreisförmigen Öffnungen in den Kammern. </li><li> Umschließen die Kammern in sterile Zellkulturschalen, und es ihnen ermöglichen, bei 37 ° C für 15 Minuten äquilibrieren. Trennen der mit Prostatazellen aus ihrem Kulturschale mit 5 ml 0,25% Trypsin-EDTA bei 37 ° C für 5 min. Neutralisieren die Trypsin-EDTA mit 5 ml 10% FBS in PBS. </li><li> Übertragen der Zellen auf 15 ml-Röhrchen und Zentrifugieren der Zellen 5 min bei 200 × g, 37 ° C. Saugt den Überstand und resuspendiere die Zellen in 1 ml Kulturmedium. </li><li> Nehmen Sie 20 μl der Zell-Lösung auf eine Zählkammer laden und berechnen Sie die Anzahl der Zellen. Stellen Sie die Zellkonzentration bis 8 × 10 4 Zellen / ml mit Kulturmedium. </li><li> Nehmen Sie die Galvanotaxis Kammern aus dem 37 ° C-Inkubator. Seed 350 ul der Zellsuspension auf jeder Kammer. </li><li> Die Zellen in der Kulturschale mit nassen Kimwipe oder in einer feuchten Kammer in den Inkubator bei 37 ° C mit 5% CO 2 inkubieren in den Kammern über Nacht. </li></ol></li></ol><img alt="Abbildung 2" fo:content-width="5in" src="/files/ftp_upload/51973/51973fig2highres.jpg" width="500" /> Abb. 2: Aussaat der Zellen in die Kammer der unteren Kammer wird getrocknet und gereinigt A) Prostata-Zellen trypsiniert, gezählt und in die Kammer überführt und über Nacht inkubiert B) Ein Top Deckglas angebracht ist, um die Kammer bevor die Dreharbeiten zu versiegeln... <ol start="3"><li> Assembling die oberen Kammern <ol><li> Montieren Sie die obere Kammer vor den Dreharbeiten. Das Mikroskop ist nur Platz Abbilden eines einzigen Galvanotaxis Kammer zu einer Zeit. Warm up 10 ml Kulturmedium bei 37 ° C für jeden Galvanotaxis Kammer. Übertragen einer Galvanotaxis Kammer aus den Brutkästen zu einer 37 ° C Warmhalteplatte. </li><li> Spülen Sie die Zellen mit Kulturmedium, um die ungebundene Zellen zu entfernen. Leave 400 ul Medium in der Kammer. Mit einer Spritze Hochvakuumfett auf der Oberseite der beiden Glasabstandshalter anwenden. </li><li> Fügen Sie eine kleine Deckglas, um die Kammer zu versiegeln. Drücken Sie vorsichtig das Deckglas mit der Rückseite eines Baumwoll-Applikator. Wischen Sie das überschüssige Medium mit Wattestäbchen. </li><li> Trocknen Sie die Glasoberfläche und gelten Hochvakuumfett, um die Lücke zwischen dem Deckglas und der Kammer zu versiegeln. Verwenden Sie eine Metallspachtel, um das Fett zu verbreiten. 4 ml des Kulturmediums zu den inneren Behälter und überprüfen Sie den Flüssigkeitsstrom zwischen den Stauseen. </li></ol></li><li> Stellen AgarBrücken <ol><li> Schneiden Sie ein Paar 2-Zoll-langen PVC-Schlauch (ID 503/16 x 16.5 mm x 16.1 Wand), Flip und fügen Sie sie in einen 100-ml-Becher. </li><li> Messung 200 mg Bacto-Agar und fügen in einem 50 ml-Kolben mit 10 ml Kulturmedium zu 2% Agargel machen. Mikrowelle für 30 Sekunden. Laden Sie die Agar-Gel auf den Kunststoffschlauch mit einer Transferpipette. Lassen Sie die Agar-Brücken bei Raumtemperatur für 10 Minuten, um den Agar verfestigt. </li><li> 2 ml Kulturmedium zu den Außenbehälter des Galvanotaxis Kammer. Legen Sie die Agar-Brücken zu den inneren und äußeren Medienspeicher, um den Strom zu leiten. </li></ol></li></ol><img alt="Figur 3" fo:content-width="3.5in" src="/files/ftp_upload/51973/51973fig3highres.jpg" width="350" /> Fig. 3: Dreh die Zellen an der Kammer ein Diagramm, um die Endmontage des Galvanotaxis Kammer demonstrieren. Die Kammer ist komplett mit Hochvakuumfett abgedichtet. Medium hinzugefügt to füllen die Stauseen und zwei Agar Brücken in die Kammer eingeführt wird. Dann wird die Galvanotaxis Kammer auf den Mikroskoptisch übertragen, und die Elektroden angebracht sind, um das elektrische Feld anzulegen. Seitenansicht des zusammengebauten Galvanotaxis Kammer gezeigt, um zu zeigen, dass der elektrische Strom in den Zellen durch die Agar-Brücken und der Raum zwischen dem Deckglas. 3. Zeitraffer-Imaging <ol><li> Einschalten der Klimakammer auf 37 ° C mit 5% CO 2 in der zirkulierenden Luft 2 h vor der Bilderzeugung. </li><li> Schalten Sie das Mikroskop und starten Sie die Bilderfassungssoftware. Kalibrieren Sie den Mikroskoptisch und wählen Sie die 10X-Objektiv. </li><li> Übertragen Sie die Galvanotaxis Kammern mit dem Mikroskoptisch, sichern Sie die Kammer mit Klebeband und konzentrieren sich auf den Zellen. Setzen Sie die Galvanotaxis Elektroden an den Außenbehälter mit Kathode auf der rechten Seite. Sichern Sie die Kabel und die Elektroden mit Klebeband. </li><li> Schalten Sie die Strom box, ein elektrisches Feld an die Kammer anzuwenden. Die Ausgangsspannung mit dem Spannungsmesser über die Kammer auf 2,5 Volt für die 25 mm lange Kammer (100 mV / mm) erreichen. Pflegen Sie die Feldstärke während des Experiments durch Anpassung des Ausgangsstroms. </li><li> Wählen Sie 10 Punkte über die Kammer in der Software zu filmen zu zehn Zeitraffer-Filme erstellen. Richten Sie die Aufnahmebedingungen im 10-Minuten-Intervallen für 2 Stunden. </li><li> Starten Dreharbeiten und stellen Sie den Ausgangsstrom je nach Bedarf. </li><li> Am Ende des Experiments, entfernen Sie die Kammer von der Bühne aus und fixieren Sie die Zellen mit 95% Alkohol. Brechen Sie den offenen Kammer mit einer Rasierklinge zu reinigen und wieder verwenden. </li></ol> 4. Quantifizierung Galvanotaxis <ol><li> Drehen Sie die Zeitraffer-Filme und neu orientieren die Kathode an die Spitze der Bilder. Exportieren Sie die Filme auf die Zelle-Tracking-Software. </li><li> Manuell verfolgen die (x, y) Position 10-20 Zellen bei jedem Zeitpunkt von jedem Film (Abbildung 4 A, B).Die Migrationsabstände und die Winkel in Bezug auf die Nord-Süd-Richtung, die gleiche Ausrichtung des elektrischen Feldes in der Zelle Verfolgungssoftware (4C) berechnet werden. HINWEIS: Die durchschnittliche Wanderungsgeschwindigkeit wird von der Gesamtlaufstrecke und Gesamtdreharbeiten Zeit konvertiert. Die Laufrichtung wird von den quer zu dem Kosinus Wert umgewandelt. Wenn Zellen wandern mit zufälliger Ausrichtung, wird der Durchschnitt der Umlauf Cosinus nahe Null sein. Wenn die Zellen wandern direkt zu der Kathode, wird die Kosinuswert +1 sein. Wenn die Zellen wandern direkt zu der Anode wird der Cosinus-Wert -1 ist. </li></ol><img alt="4" fo:content-width="4in" src="/files/ftp_upload/51973/51973fig4highres.jpg" width="400" /> Abbildung 4: Zellverfolgung zu Direktionalität messen A) Überlagerung der Spurlinien mit Zellbildern.. Die (x, y) -Positionen der Zellen manually im Zeitraffer-Filmen verfolgt. . Wenn die Zellen wandern zufällig ist die mittlere Kosinus nahe Null B) Wenn jedoch die Zellen wandern in Richtung der Kathode oder der Anode, ist der Wert des durchschnittlichen Cosinus nahe + (Kathode) - oder. (Anode) 1.0 C ) Die Laufrichtung wird durch den Kosinus-Wert, der aus den Migrationswinkel (θ) umgewandelt wird, dargestellt. Der Kosinus (θ) gleich dem Verhältnis des Abstandes a (die Migrationsdistanz) auf Abstand b (der Abstand zu der Richtung des elektrischen Feldes projiziert). <ol start="3"><li> Speichern Sie die Messungen. Importieren der Daten in eine Datenbankanwendung, die kombinierten Ergebnisse zu berechnen. </li><li> Exportieren Sie die kombinierten Daten der durchschnittlichen Wanderungsgeschwindigkeit und Durchschnitts Kosinuswert in eine Tabellenkalkulation, um die Balkendiagramme (Abbildung 5) zu zeichnen. </li></ol>

<ol>
	<li>Reid, B., Nuccitelli, R., Zhao, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-invasive+measurement+of+bioelectric+currents+with+a+vibrating+probe.">Non-invasive measurement of bioelectric currents with a vibrating probe.</a> Nat Protoc. 2 (3), 661-669 (2007).</li><li>Cao, 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=Endogenous+electric+currents+might+guide+rostral+migration+of+neuroblasts.">Endogenous electric currents might guide rostral migration of neuroblasts.</a> EMBO Rep. 14 (2), 184-190 (2013).</li><li>Hotary, K. B., Robinson, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Endogenous+electrical+currents+and+voltage+gradients+in+Xenopus+embryos+and+the+consequences+of+their+disruption.">Endogenous electrical currents and voltage gradients in Xenopus embryos and the consequences of their disruption.</a> Dev Biol. 166 (2), 789-800 (1994).</li><li>Hotary, K. B., Robinson, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evidence+of+a+role+for+endogenous+electrical+fields+in+chick+embryo+development.">Evidence of a role for endogenous electrical fields in chick embryo development.</a> Development. 114 (4), 985-996 (1992).</li><li>Yamashita, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electric+axon+guidance+in+embryonic+retina:+galvanotropism+revisited.">Electric axon guidance in embryonic retina: galvanotropism revisited.</a> Biochem Biophys Res Commun. 431 (2), 280-283 (2013).</li><li>Wood, M. D., Willits, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Applied+electric+field+enhances+DRG+neurite+growth:+influence+of+stimulation+media,+surface+coating+and+growth+supplements.">Applied electric field enhances DRG neurite growth: influence of stimulation media, surface coating and growth supplements.</a> J Neural Eng. 6 (4), 046003 (2009).</li><li>Kucerova, R., 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=The+role+of+electrical+signals+in+murine+corneal+wound+re-epithelialization.">The role of electrical signals in murine corneal wound re-epithelialization.</a> J Cell Physiol. 226 (6), 1544-1553 (2011).</li><li>Sillman, A. L., Quang, D. M., Farboud, B., Fang, K. S., Nuccitelli, R., Isseroff, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+Dermal+fibroblasts+do+not+exhibit+directional+migration+on+collagen+I+in+direct-current+electric+fields+of+physiological+strength.">Human Dermal fibroblasts do not exhibit directional migration on collagen I in direct-current electric fields of physiological strength.</a> Exp Dermatol. 12 (4), 396-402 (2003).</li><li>Allen, G. M., Mogilner, A., Theriot, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrophoresis+of+cellular+membrane+components+creates+the+directional+cue+guiding+keratocyte+galvanotaxis.">Electrophoresis of cellular membrane components creates the directional cue guiding keratocyte galvanotaxis.</a> Curr Biol. 23 (7), 560-568 (2013).</li><li>Nishimura, K. Y., Isseroff, R. R., Nuccitelli, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+keratinocytes+migrate+to+the+negative+pole+in+direct+current+electric+fields+comparable+to+those+measured+in+mammalian+wounds.">Human keratinocytes migrate to the negative pole in direct current electric fields comparable to those measured in mammalian wounds.</a> J Cell Sci. 109 (1), 199-207 (1996).</li><li>Farboud, B., Nuccitelli, R., Schwab, I. R., Isseroff, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DC+electric+fields+induce+rapid+directional+migration+in+cultured+human+corneal+epithelial+cells.">DC electric fields induce rapid directional migration in cultured human corneal epithelial cells.</a> Exp Eye Res. 70 (5), 667-673 (2000).</li><li>Fang, K. S., Ionides, E., Oster, G., Nuccitelli, R., Isseroff, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidermal+growth+factor+receptor+relocalization+and+kinase+activity+are+necessary+for+directional+migration+of+keratinocytes+in+DC+electric+fields.">Epidermal growth factor receptor relocalization and kinase activity are necessary for directional migration of keratinocytes in DC electric fields.</a> J Cell Sci. 112 (12), 1967-1978 (1999).</li><li>Li, J., 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=Activated+T+lymphocytes+migrate+toward+the+cathode+of+DC+electric+fields+in+microfluidic+devices.">Activated T lymphocytes migrate toward the cathode of DC electric fields in microfluidic devices.</a> Lab Chip. 11 (7), 1298-1304 (2011).</li><li>Meng, X., Arocena, M., Penninger, J., Gage, F. H., Zhao, M., Song, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PI3K+mediated+electrotaxis+of+embryonic+and+adult+neural+progenitor+cells+in+the+presence+of+growth+factors.">PI3K mediated electrotaxis of embryonic and adult neural progenitor cells in the presence of growth factors.</a> Exp Neurol. 227 (1), 210-217 (2011).</li><li>Wu, D., Ma, X., Lin, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DC+Electric+Fields+Direct+Breast+Cancer+Cell+Migration,+Induce+EGFR+Polarization,+and+Increase+the+Intracellular+Level+of+Calcium+Ions.+.">DC Electric Fields Direct Breast Cancer Cell Migration, Induce EGFR Polarization, and Increase the Intracellular Level of Calcium Ions. .</a> Cell Biochem Biophys. 67 (3), 1115-1125 (2013).</li><li>Martin-Granados, C., 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+role+for+PP1/NIPP1+in+steering+migration+of+human+cancer+cells.">A role for PP1/NIPP1 in steering migration of human cancer cells.</a> PLoS One. 7 (7), 40769 (2012).</li><li>Yang, H. Y., Charles, R. P., Hummler, E., Baines, D. L., Isseroff, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+epithelial+sodium+channel+mediates+the+directionality+of+galvanotaxis+in+human+keratinocytes.">The epithelial sodium channel mediates the directionality of galvanotaxis in human keratinocytes.</a> J Cell Sci. 126 (9), 1942-1951 (2013).</li><li>Zhao, 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=Electrical+signals+control+wound+healing+through+phosphatidylinositol-3-OH+kinase-gamma+and+PTEN.">Electrical signals control wound healing through phosphatidylinositol-3-OH kinase-gamma and PTEN.</a> Nature. 442 (7101), 457-460 (2006).</li><li>Shanley, L. J., Walczysko, P., Bain, M., MacEwan, D. J., Zhao, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influx+of+extracellular+Ca2++is+necessary+for+electrotaxis+in+Dictyostelium.">Influx of extracellular Ca2+ is necessary for electrotaxis in Dictyostelium.</a> J Cell Sci. 119 (22), 4741-4748 (2006).</li><li>Zhao, M., Agius-Fernandez, A., Forrester, J. V., McCaig, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Directed+migration+of+corneal+epithelial+sheets+in+physiological+electric+fields.">Directed migration of corneal epithelial sheets in physiological electric fields.</a> Invest Ophthalmol Vis Sci. 37 (13), 2548-2558 (1996).</li><li>Peng, H. B., Jaffe, L. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polarization+of+fucoid+eggs+by+steady+electrical+fields.">Polarization of fucoid eggs by steady electrical fields.</a> Dev Biol. 53 (2), 277-284 (1976).</li><li>Lee, 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=Characterization+of+adult+human+prostatic+epithelial-cells+immortalized+by+polybrene-induced+DNA+transfection+with+a+plasmid+containing+an+origin-defective+sv40-genome.">Characterization of adult human prostatic epithelial-cells immortalized by polybrene-induced DNA transfection with a plasmid containing an origin-defective sv40-genome.</a> Int J Oncol. 4 (4), 821-830 (1994).</li><li>Berthon, P., Cussenot, O., Hopwood, L., Leduc, A., Maitland, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+expression+of+sv40+in+normal+human+prostatic+epithelial+and+fibroblastic+cells+-+differentiation+pattern+of+non-tumorigenic+cell-lines.">Functional expression of sv40 in normal human prostatic epithelial and fibroblastic cells - differentiation pattern of non-tumorigenic cell-lines.</a> Int J Oncol. 6 (2), 333-343 (1995).</li><li>Aurich-Costa, J., Vannier, A., Gr&#233;goire, E., Nowak, F., Cherif, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=IPM-FISH,+a+new+M-FISH+approach+using+IRS-PCR+painting+probes:+application+to+the+analysis+of+seven+human+prostate+cell+lines.">IPM-FISH, a new M-FISH approach using IRS-PCR painting probes: application to the analysis of seven human prostate cell lines.</a> Genes Chromosomes Cancer. 30 (2), 143-160 (2001).</li><li>Tyson, D. R., Inokuchi, J., Tsunoda, T., Lau, A., Ornstein, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Culture+requirements+of+prostatic+epithelial+cell+lines+for+acinar+morphogenesis+and+lumen+formation+in+vitro:+role+of+extracellular+calcium.">Culture requirements of prostatic epithelial cell lines for acinar morphogenesis and lumen formation in vitro: role of extracellular calcium.</a> Prostate. 67 (15), 1601-1613 (2007).</li><li>Lang, S. H., Sharrard, R. M., Stark, M., Villette, J. M., Maitland, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prostate+epithelial+cell+lines+form+spheroids+with+evidence+of+glandular+differentiation+in+three-dimensional+Matrigel+cultures.">Prostate epithelial cell lines form spheroids with evidence of glandular differentiation in three-dimensional Matrigel cultures.</a> Br J Cancer. 85 (4), 590-599 (2001).</li><li>Babona-Pilipos, R., Popovic, M. R., Morshead, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+galvanotaxis+assay+for+analysis+of+neural+precursor+cell+migration+kinetics+in+an+externally+applied+direct+current+electric+field.">A galvanotaxis assay for analysis of neural precursor cell migration kinetics in an externally applied direct current electric field.</a> J Vis Exp. (68), (2012).</li><li>Meng, X., 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=Electric+field-controlled+directed+migration+of+neural+progenitor+cells+in+2D+and+3D+environments.">Electric field-controlled directed migration of neural progenitor cells in 2D and 3D environments.</a> J Vis Exp. (60), (2012).</li><li>Pullar, C. E., Isseroff, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclic+AMP+mediates+keratinocyte+directional+migration+in+an+electric+field.">Cyclic AMP mediates keratinocyte directional migration in an electric field.</a> J Cell Sci. 118 (9), 2023-2034 (2005).</li><li>Sheridan, D. M., Isseroff, R. R., Nuccitelli, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imposition+of+a+physiologic+DC+electric+field+alters+the+migratory+response+of+human+keratinocytes+on+extracellular+matrix+molecules.">Imposition of a physiologic DC electric field alters the migratory response of human keratinocytes on extracellular matrix molecules.</a> J Invest Dermatol. 106 (4), 642-646 (1996).</li><li>Feng, J. 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=Guided+migration+of+neural+stem+cells+derived+from+human+embryonic+stem+cells+by+an+electric+field.">Guided migration of neural stem cells derived from human embryonic stem cells by an electric field.</a> Stem Cells. 30 (2), 349-355 (2012).</li><li>Mukerjee, E. V., Isseroff, R. R., Nuccitelli, R., Collins, S. D., Smith, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microneedle+array+for+measuring+wound+generated+electric+fields.">Microneedle array for measuring wound generated electric fields.</a> Conf Proc IEEE Eng Med Biol Soc. 1, 4326-4328 (2006).</li><li>Nuccitelli, R., Nuccitelli, P., Li, C., Narsing, S., Pariser, D. M., Lui, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+electric+field+near+human+skin+wounds+declines+with+age+and+provides+a+noninvasive+indicator+of+wound+healing.">The electric field near human skin wounds declines with age and provides a noninvasive indicator of wound healing.</a> Wound Rep. and Reg. 19, 645-655 (2011).</li></ol>

The authors have nothing to disclose.

Die Analyse der Galvanotaxis Reaktion einer Zelle ist ein wichtiger Funktionsanzeige für viele zelluläre Migrations oder Wachstumsprozesse 27, 28. Hier nutzen wir eine maßgeschneiderte Kammer mit Glasoberfläche, um zwei Prostata-Zelllinien zu filmen. Diese Zellinien zeigten unterschiedliche Grade der Galvanotaxis, und wir vermuten, dass die intrazelluläre Lokalisierung oder die Aktivierung der Galvanotaxis vermittelnde Proteine ​​könnte während des Prozesses der Erzeugung der unsterblichen Zelllini...

Endogene elektrische Felder in verschiedenen Geweben, wie der Haut 1, 32, 33 und Gehirn 2 detektiert. Die physiologischen elektrischen Feldes dient spezifische biologische Funktionen, einschließlich Leiten Embryonalentwicklung 3, 4, Führen des Auswachsen von neuronalen Prozessen 5, 6 und Förderung Epithel- und Hornhautwundverschluss 1, 7. In vitro-Anwendung eines elektrischen Gleichstromfeldes an kultivierte Zellen ahmt die physiologischen elektrischen Feld und induziert Richtungszellmigration oder Galvanotaxis. Galvanotaxis in Fibroblasten 8, Fisch Keratinozyten 9, humanen epithelialen und Hornhaut Keratinozyten 10-12 untersucht worden, Lymphozyten 13, Neuroblasten 2 und neuronale Vorläuferzellen 14. Wenn zu dem angelegten Feld ausgesetzt sind, die Mehrzahl der untersuchten Zellen wandern gerichtet in Richtung der kathodenseitigen Pol (-). Dennoch verschiedenen Krebszellen, einschließlich hochmetastatischmenschliche Brustkrebszellen, und der menschliche Prostatakrebs-Zelllinie PC-3M, zu bewegen, um die anodenseitige Pol (+) 15, 16. Verschiedene Mechanismen sind vorgeschlagen Galvanotaxis vermitteln oder die Fähigkeit der Zellen, um das elektrische Feld zu erfassen, einschließlich der Aktivierung erklären der EGF-Rezeptoren 12, die epithelialen Natriumkanals 17, PI3K und PTEN 18, und die Freisetzung von Calciumionen 15, 19. Der Mechanismus ist noch nicht vollständig verstanden, und es ist möglich, dass mehrere Signalwege in Galvanotaxis beteiligt. Die 2-dimensionalen Galvanotaxis Verfahren wir hier zeigen, ist nützlich, um die gerichtete Migration von adhärenten, bewegliche Zellen zu charakterisieren, auf einzelne Zellmigration 10, 12, 17 oder Migration einer Lage von zusammenhängenden Zellen 18, 20. Diese Technik ist aus modifizierten überwachen Peng und Jaffe 21 und Nishimura et al. 10 mit maßgeschneiderten, klarem PVC Kammern mit herausnehmbaren coverslips erlaubt eine einfache Zellentnahme nach Galvanotaxis für die Sekundäranalyse, wie zum Beispiel Immunfluoreszenz-Bildgebung. Die Glasoberfläche der Galvanotaxis Kammern optischen kompatibel, was die Filmbildung bei hoher Vergrößerung und mit fluoreszenzmarkierten Zellen erlaubt. Es ermöglicht auch das experimentelle Design mit Modifizierung der Glasoberfläche, wie die Änderung der Oberflächenbeschichtung oder Ladungen. Spacer aus No. 1 Abdeckglas gebildet in den Kammern verwendet, um den Stromfluss in den Zellen zu minimieren; damit die Joulesche Erwärmung, die proportional zu dem Quadrat des Stromflusses ist, würden die Zellen nicht während des Experimentes hitzen. Die Verbindungs ​​Agar Brücken verhindern einen direkten Kontakt der Elektroden mit den Zellen und Änderung des Mediums pH oder Ionenkonzentration während Galvanotaxis verhindern. Zwei nicht-tumorigene menschliche Prostata-Zelllinien wurden hinsichtlich ihrer Galvanotaxis Reaktion in dieser Studie untersucht. Die PRNs-1-1 22 und 23 sind beide PNT2 SV40 immortalisierte, Wachstumsfaktor-abhängigen Zelllinien, welche die epithelialen Marker Cytokeratin 5, 8, 18 und 19 mit geringer oder keiner Expression des Prostata-spezifisches Antigen (PSA). Beide Zelllinien halten die polygonale Morphologie von normalen Epithelzellen, aber Chromosomenanomalie in Karyotypisierung 22, 24 festgestellt. Obwohl PRN-1-1 und PNT2 teilen ähnliche Verhaltensweisen in den meisten Experimenten zeigen sie Unterschiede bei der Bildung der Struktur und in azinösen Galvanotaxis. In einem 3-D-Matrix, Matrigel, die PRN-1-1 Zellen bilden Hohl acinar Strukturen mit Lumen ähnlich der normalen Prostatagewebe 25. Allerdings sind die PNT2 Zellen bilden feste Kügelchen ohne Lumen oder polarisierten Epithel 26. Die PRNs-1-1-Zellen eine höhere galvanotactic Antwort als die PNT2 in der aktuellen Studie zeigen auch. Die Korrelation zwischen der Bildung von acinar Struktur und Galvanotaxis in PRNs-1-1 schlägt vor, dass die galvanotactic Signale können eine Rolle bei der Organisation der pr spielenostate Drüsengewebe Bewegungen als Reaktion auf endogene elektrische Felder, und stellt weitere Merkmale, um zwischen diesen 2 Zelllinien unterscheiden.

<table border="0" cellpadding="0" cellspacing="0" width="774">
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			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:117px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:323px;">Comments/Description</td>
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			<td height="21" style="height:21px;width:216px;">Cells</td>
			<td style="width:117px;"></td>
			<td style="width:119px;"></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">pRNS-1-1 prostate cells</td>
			<td style="width:117px;"></td>
			<td style="width:119px;"></td>
			<td>Lee et. al., (1994)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PNT2 prostate cells</td>
			<td style="width:117px;">Sigma-Aldrich</td>
			<td style="width:119px;">95012613-1VL</td>
			<td>Berthon et al., (1995)</td>
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			<td height="21" style="height:21px;">Medium and solutions</td>
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			<td style="width:119px;"></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">RPMI 1640 medium&#160;</td>
			<td style="width:117px;">Invitrogen</td>
			<td style="width:119px;">11875-093</td>
			<td>warm up to 37&#176;C before use</td>
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		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Fetal Bovine Serum - Premium</td>
			<td style="width:117px;">Atlanta Biologicals</td>
			<td style="width:119px;">S11150</td>
			<td>10% in PBS, warm up to 37&#176;C before use</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Antibiotic-Antimycotic (100x)</td>
			<td style="width:117px;">Life Technologies</td>
			<td style="width:119px;">15240</td>
			<td>add 5mL to 500mL medium</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">2-propanol</td>
			<td style="width:117px;">VWR</td>
			<td>BDH1133-5GL</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">PBS</td>
			<td style="width:117px;">-</td>
			<td style="width:119px;">-</td>
			<td>137mM NaCl, 2.7mM KCl, 4.3mM Na2HPO4 and 1.5mM KH2PO4 in 1000mL of H2O, pH to 7.4 and autoclaved, warm up to 37&#176;C before use</td>
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		<tr height="21">
			<td height="21" style="height:21px;">0.25% Trypsin-EDTA&#160;</td>
			<td style="width:117px;">Invitrogen</td>
			<td style="width:119px;">25200-056</td>
			<td>warm up to 37&#176;C before use, treat cells for 3-5 min at 37&#176;C</td>
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		<tr height="21">
			<td height="21" style="height:21px;">Galvanotaxis device</td>
			<td style="width:117px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Galvanotaxis chambers</td>
			<td style="width:117px;">Precision Plastics Inc, CA</td>
			<td style="width:119px;"></td>
			<td>custom-designed (1/4&#34; X 2&#34; X 3.5&#34;), non-toxic, clear PVC chambers</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Galvanotaxis electrodes</td>
			<td style="width:117px;">UCD electric shop</td>
			<td style="width:119px;"></td>
			<td>platinum coiled electrodes with flexable cords</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Galvanotaxis power box</td>
			<td style="width:117px;">Substrate Engineering, CA</td>
			<td style="width:119px;"></td>
			<td>custom-designed DC power output with voltmeter</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Microscope Cover Glass, Large, 45X50mm-No. 1.5</td>
			<td style="width:117px;">Fisher</td>
			<td style="width:119px;">12-544-F</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Microscope Cover Glass, small, 25X25mm, No. 1</td>
			<td style="width:117px;">ThermoScientific</td>
			<td style="width:119px;">3307</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Diamond point marker</td>
			<td style="width:117px;">ThermoScientific</td>
			<td style="width:119px;">750</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Marine grade silicon sealer, clear</td>
			<td style="width:117px;">3M</td>
			<td style="width:119px;">051135-08019</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">High vacuum grease</td>
			<td style="width:117px;">Dow Corning</td>
			<td style="width:119px;">2021846-0807</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">6mL syringe</td>
			<td style="width:117px;">Fisher Scientific</td>
			<td style="width:119px;">05-561-64</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Nichiryo Syringe, 1.5mL</td>
			<td style="width:117px;">Nichiryo</td>
			<td style="width:119px;">SG-M</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Cotton applicators</td>
			<td style="width:117px;">Purtian Medical Products</td>
			<td style="width:119px;">806-WC</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Qtips</td>
			<td style="width:117px;">Johnson &#38; Johnson</td>
			<td style="width:119px;">729389</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Nalgene 180 PVC tubing&#160;</td>
			<td style="width:117px;">Nalgene</td>
			<td style="width:119px;">8000-9030</td>
			<td>503/16 ID x 5/16 OD x 1/16 Wall</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bacto-Agar</td>
			<td style="width:117px;">Difco</td>
			<td style="width:119px;">0140-01</td>
			<td>make 2% agar solution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Razor Blade</td>
			<td style="width:117px;">Personna</td>
			<td style="width:119px;">74-0001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Equipments and Software</td>
			<td style="width:117px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Benchtop Centrifuge</td>
			<td style="width:117px;">Eppendorf</td>
			<td style="width:119px;">5810R</td>
			<td>operated with an A-4-62 rotor</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cellometer Auto T4</td>
			<td style="width:117px;">Nexcelom</td>
			<td style="width:119px;">Auto T4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Cellometer counting chambers</td>
			<td style="width:117px;">Nexcelom</td>
			<td style="width:119px;">CHT4-SD100-002</td>
			<td>load 20uL cell solutions to count</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Culture Temp Warming plate</td>
			<td style="width:117px;">Bel-Art Scienceware</td>
			<td style="width:119px;">370150000</td>
			<td>to keep the galvanotaxis chambers at 37&#176;C&#160;</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Eclipse TE-2000 microscope with motorized stage and environmental chamber</td>
			<td style="width:117px;">Nikon</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Plan Fluor 10X/0.30 objective len</td>
			<td style="width:117px;">Nikon</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Retiga EX CCD camera&#160;</td>
			<td style="width:117px;">Qimaging</td>
			<td style="width:119px;"></td>
			<td>Cooled CCD camara, mono-color, 12-bit</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Compressed air with 5% CO2&#160;</td>
			<td style="width:117px;">Airgas</td>
			<td style="width:119px;"></td>
			<td>special order</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Volocity 6.3</td>
			<td style="width:117px;">PerkinElmer</td>
			<td style="width:119px;"></td>
			<td>Image acquiring software</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Improvision OpenLab 5.5.2</td>
			<td style="width:117px;">PerkinElmer</td>
			<td style="width:119px;"></td>
			<td>Cell tracking software and customized to measure migration angles</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">FileMaker Pro Advanced, 8.0</td>
			<td style="width:117px;">FileMaker</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Microsoft Excel 2008 for Mac</td>
			<td style="width:117px;">Microsoft</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

utilizing custom-designed galvanotaxis chambers to study directional migration of prostate cells

Die physiologische elektrische Feld dient spezifische biologische Funktionen, wie zB die Leitung der Zellmigration in der Embryonalentwicklung, neuronale Auswachsen und epithelialen Wundheilung. Anlegen eines Gleichstromfeldes, um kultivierte Zellen in vitro induziert gerichteten Zellmigration oder Galvanotaxis. Die 2-dimensionalen Galvanotaxis Verfahren wir hier zeigen, wird mit maßgeschneiderten Poly (vinylchlorid) (PVC) Kammern, Glasoberfläche, Platin-Elektroden und der Verwendung eines motorisierten Tisch, auf dem die Zellen abgebildet werden modifiziert. Die PVC-Kammern und Platinelektroden eine geringe Zytotoxizität und sind erschwinglich und wiederverwendbare. Die Glasoberfläche und der motorisierten Mikroskoptisch zur Verbesserung der Qualität der Bilder und lassen mögliche Änderungen an der Glasoberfläche und Anwendungen zu den Zellen. Wir filmten die Galvanotaxis von zwei nicht-tumor, SV40-immortalisierten Prostata-Zelllinien, PRNs-1-1 und PNT2. Diese beiden Zelllinien zeigen ähnliche Migrationsgeschwindigkeiten und beide wandern zudie Kathode, aber sie zeigen ein unterschiedliches Maß an Richtwirkung in Galvanotaxis. Die über dieses Protokoll erhaltenen Ergebnisse deuten darauf hin, dass die PRN-1-1 und die PNT2 Zelllinien können unterschiedliche intrinsische Eigenschaften, die ihren Richtungsmigrations Antworten zu regieren.

Zwei Linien der Prostatazellen (PRNs-1-1 und PNT2) wurden mit dieser Methode untersucht. Zellen in beiden Leitungen wandern bei ähnlichen Geschwindigkeiten von 1,0 +/- 0,3 um / min im Verlauf von 2-Stunden (5A). , Die Direktionalität zu dem elektrischen Feld ist jedoch 0,7 +/- 0,3 für das PRN-1-1 Linie und 0,2 +/- 0,8 für die PNT2 Leitung (5B). Die Ergebnisse zeigen einen signifikanten Unterschied in der Galvanotaxis dieser beiden Zelllinien (p &lt;0,01, 100-Zellen wurden verfolgt),...

Watch this Scientific Journal Video about Utilizing Custom-designed Galvanotaxis Chambers to Study Directional Migration of Prostate Cells at JoVE.com

Utilizing Custom-designed Galvanotaxis Chambers to Study Directional Migration of Prostate Cells

We present a method to apply a physiological electric field to migrating, immortalized prostate cells in a custom-made galvanotaxis chamber. Using this method, we demonstrate that 2 lines of non-tumorigenic prostate cells demonstrate different degrees of migration directionality in the field.

Verwendung Maßgeschneiderte Galvanotaxis Chambers zu Directional Migration Studie von Prostatazellen

The physiological electric field serves specific biological functions, such as directing cell migration in embryo development, neuronal outgrowth and ...

utilizing-custom-designed-galvanotaxis-chambers-to-study-directional

Research

JoVE Journal

Biology

9.1K Aufrufe.  University of California, Davis. We present a method to apply a physiological electric field to migrating, immortalized prostate cells in a custom-made galvanotaxis chamber. Using this method, we demonstrate that 2 lines of non-tumorigenic prostate cells demonstrate different degrees of migration directionality in the field.

Serie: Utilizing Custom-designed Galvanotaxis Chambers to Study Directional Migration of Prostate Cells

Testing Visual Sensitivity to the Speed and Direction of Motion in Lizards

Testing visual sensitivity in any species provides basic information regarding behaviour, evolution, and ecology. However, testing specific features of the visual system provide more empirical evidence for functional applications. Investigation into the sensory system provides information about the sensory capacity, learning and memory ability, and establishes known baseline behaviour in which to gauge deviations (Burghardt, 1977). However, unlike mammalian or avian systems, testing for learning and memory in a reptile species is difficult. Furthermore, using an operant paradigm as a psychophysical measure of sensory ability is likewise as difficult. Historically, reptilian species have responded poorly to conditioning trials because of issues related to motivation, physiology, metabolism, and basic biological characteristics. Here, I demonstrate an operant paradigm used a novel model lizard species, the Jacky dragon (Amphibolurus muricatus) and describe how to test peripheral sensitivity to salient speed and motion characteristics. This method uses an innovative approach to assessing learning and sensory capacity in lizards. I employ the use of random-dot kinematograms (RDKs) to measure sensitivity to speed, and manipulate the level of signal strength by changing the proportion of dots moving in a coherent direction. RDKs do not represent a biologically meaningful stimulus, engages the visual system, and is a classic psychophysical tool used to measure sensitivity in humans and other animals. Here, RDKs are displayed to lizards using three video playback systems. Lizards are to select the direction (left or right) in which they perceive dots to be moving. Selection of the appropriate direction is reinforced by biologically important prey stimuli, simulated by computer-animated invertebrates.

Testing visual sensitivity in lizards using an operant conditioning paradigm that employs video playback of random-dot kinematograms and computer-generated invertebrates.

Testen visueller Sensibilität für die Geschwindigkeit und Richtung der Bewegung in Lizards

Testing visual sensitivity in any species provides basic information regarding behaviour, evolution, and ecology. However, testing specific features of ...

Forschung

Biologie

A Cell-to-cell Macromolecular Transport Assay in Planta Utilizing Biolistic Bombardment

Here, we present a simple and rapid protocol to detect and assess the extent of cell-to-cell macromolecular transport in planta. In this protocol, a fluorescently tagged-protein of interest is transiently expressed in plant tissue following biolistic delivery of its encoding DNA construct. The intra- and intercellular distribution of the tagged protein is then analyzed by confocal microscopy. We describe this technology in detail, providing step-by-step protocols to assay and evaluate the extent of symplastic protein transport in three plant species, Arabidopsis thaliana, Nicotiana benthamiana and N. tabacum (tobacco).

A Cell-to-cell Macromolecular Transport Assay in Planta Utilizing Biolistic Bombardment

Macromolecular trafficking between plant cells can be assessed by transiently expressing a fluorescently-tagged protein of interest and analyzing its intra- and intercellular distribution by confocal microscopy.

Ein Cell-to-cell Makromolekulare Transport Assay In Planta Verwendung Biolistic Bombardment

Here, we present a simple and rapid protocol to detect and assess the extent of cell-to-cell macromolecular transport in planta. In this protocol, a ...

Quantitative Analysis of Random Migration of Cells Using Time-lapse Video Microscopy

Cell migration is a dynamic process, which is important for embryonic development, tissue repair, immune system function, and tumor invasion 1, 2. During directional migration, cells move rapidly in response to an extracellular chemotactic signal, or in response to intrinsic cues 3 provided by the basic motility machinery. Random migration occurs when a cell possesses low intrinsic directionality, allowing the cells to explore their local environment.
Cell migration is a complex process, in the initial response cell undergoes polarization and extends protrusions in the direction of migration 2. Traditional methods to measure migration such as the Boyden chamber migration assay is an easy method to measure chemotaxis in vitro, which allows measuring migration as an end point result. However, this approach neither allows measurement of individual migration parameters, nor does it allow to visualization of morphological changes that cell undergoes during migration.
Here, we present a method that allows us to monitor migrating cells in real time using video - time lapse microscopy. Since cell migration and invasion are hallmarks of cancer, this method will be applicable in studying cancer cell migration and invasion in vitro. Random migration of platelets has been considered as one of the parameters of platelet function 4, hence this method could also be helpful in studying platelet functions. This assay has the advantage of being rapid, reliable, reproducible, and does not require optimization of cell numbers. In order to maintain physiologically suitable conditions for cells, the microscope is equipped with CO2 supply and temperature thermostat. Cell movement is monitored by taking pictures using a camera fitted to the microscope at regular intervals. Cell migration can be calculated by measuring average speed and average displacement, which is calculated by Slidebook software.

This method allows monitoring of cells in real time and quantitative measurements of different cell migration parameters such as speed, displacement, and velocity. Unlike the traditional methods, this real time approach is not based on endpoint quantitative migration measurements; instead it allows monitoring and calculating different parameters continuously.

Quantitative Analyse der ungerichtete Migration von Zellen unter Verwendung Zeitraffer-Video-Mikroskopie

Cell migration is a dynamic process, which is important for embryonic development, tissue repair, immune system function, and tumor invasion 1, 2. During ...

Preparing Individual Drosophila Egg Chambers for Live Imaging

Live cell imaging is an important technique applied to a number of Drosophila tissues used as models to investigate topics such as axis specification, cell differentiation and organogenesis 1. Correct preparation of the experimental samples is a crucial, often neglected, step. The goal of preparation is to ensure physiological relevance and to establish optimal imaging conditions. To maintain tissue viability, it is critical to avoid dehydration, hypoxia, overheating or medium deterioration 2. 
 The Drosophila egg chamber is a well established system for examining questions relating, but not limited, to body patterning, mRNA localization and cytoskeletal organization 3,4. For early- and mid-stage egg chambers, mounting in halocarbon oil is good for survival in that it allows free diffusion of oxygen, prevents dehydration and hypoxia and has superb optical properties for microscopy. Imaging of fluorescent proteins is possible through the introduction of transgenes into the egg chamber or physical injection of labeled RNA, protein or antibodies 5-7. For example, addition of MS2 constructs to the genome of animals enables real time observation of mRNAs in the oocyte 8. These constructs allow for in vivo labeling of mRNA through utilization of the MS2 bacteriophage RNA stem loop interaction with its coat protein 9. 
 Here, we present a protocol for the extraction of ovaries as well as isolating individual ovarioles and egg chambers from the female Drosophila. For a detailed description of Drosophila oogenesis see Allan C. Spradling (1993, reprinted 2009) 10.

Preparing Individual Drosophila Egg Chambers for Live Imaging

The Drosophila egg chamber is an excellent model for studying the mechanisms of mRNA localization. In order to capture the dynamic events that underpin the processes of localization, rapid high resolution imaging of live tissue is required. Here, we present a protocol for dissection and imaging of live samples with minimal disruption.

Der Ausarbeitung der einzelnen Drosophila Ei Chambers für Live-Imaging

Live cell imaging is an important technique applied to a number of Drosophila tissues used as models to investigate topics such as axis specification, ...

Induction and Analysis of Epithelial to Mesenchymal Transition

Epithelial to mesenchymal transition (EMT) is essential for proper morphogenesis during development. Misregulation of this process has been implicated as a key event in fibrosis and the progression of carcinomas to a metastatic state. Understanding the processes that underlie EMT is imperative for the early diagnosis and clinical control of these disease states. Reliable induction of EMT in vitro is a useful tool for drug discovery as well as to identify common gene expression signatures for diagnostic purposes. Here we demonstrate a straightforward method for the induction of EMT in a variety of cell types. Methods for the analysis of cells pre- and post-EMT induction by immunocytochemistry are also included. Additionally, we demonstrate the effectiveness of this method through antibody-based array analysis and migration/invasion assays.

A straightforward method is described for the induction of epithelial to mesenchymal transition (EMT) in a variety of cell types. Methods for the analysis of cells in EMT states by immunocytochemistry are included.

Induktion und Analyse von epithelialen zu mesenchymalen Transition

Epithelial  to mesenchymal transition (EMT) is essential for proper morphogenesis during  development. Misregulation of this  process has been implicated ...

Using Caco-2 Cells to Study Lipid Transport by the Intestine

Studies of dietary fat absorption are generally conducted by using an animal model equipped with a lymph cannula. Although this animal model is widely accepted as the in vivo model of dietary fat absorption, the surgical techniques involved are challenging and expensive. Genetic manipulation of the animal model is also costly and time consuming. The alternative in vitro model is arguably more affordable, timesaving, and less challenging. Importantly, the in vitro model allows investigators to examine the enterocytes as an isolated system, reducing the complexity inherent in the whole organism model. This paper describes how human colon carcinoma cells (Caco-2) can serve as an in vitro model to study the enterocyte transport of lipids, and lipid-soluble drugs and vitamins. It explains the proper maintenance of Caco-2 cells and the preparation of their lipid mixture; and it further discusses the valuable option of using the permeable membrane system. Since differentiated Caco-2 cells are polarized, the main advantage of using the permeable membrane system is that it separates the apical from the basolateral compartment. Consequently, the lipid mixture can be added to the apical compartment while the lipoproteins can be collected from the basolateral compartment. In addition, the effectiveness of the lentivirus expression system in upregulating gene expression in Caco-2 cells is discussed. Lastly, this paper describes how to confirm the successful isolation of intestinal lipoproteins by transmission electron microscopy (TEM).

Caco-2 cells can serve as an in vitro model to study the enterocyte transport of lipids, and lipid-soluble drugs/vitamins. The permeable membrane system separates the apical from the basolateral compartment, while the lentivirus expression system offers an effective gene overexpression method. The isolation of lipoproteins is confirmed by TEM.

Verwenden von Caco-2-Zellen, die Lipidtransport Studie der Darm

Studies of dietary fat absorption are generally conducted by using an animal model equipped with a lymph cannula. Although this animal model is widely ...

Nephrotoxin Microinjection in Zebrafish to Model Acute Kidney Injury

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid decline in renal function and development of the clinical syndrome known as acute kidney injury (AKI). Pharmacological agents used to treat medical circumstances ranging from bacterial infection to cancer, when administered individually or in combination with other drugs, can initiate AKI. Zebrafish are a useful animal model to study the chemical effects on renal function in vivo, as they form an embryonic kidney comprised of nephron functional units that are conserved with higher vertebrates, including humans. Further, zebrafish can be utilized to perform genetic and chemical screens, which provide opportunities to elucidate the cellular and molecular facets of AKI and develop therapeutic strategies such as the identification of nephroprotective molecules. Here, we demonstrate how microinjection into the zebrafish embryo can be utilized as a paradigm for nephrotoxin studies.

Renal injuries incurred from nephrotoxins, which include drugs ranging from antibiotics to chemotherapeutics, can result in complex disorders whose pathogenesis remains incompletely understood. This protocol demonstrates how zebrafish can be used for disease modeling of these conditions, which can be applied to the identification of renoprotective measures.

Nephrotoxin Mikroinjektion in Zebrabärbling akuten Nierenschädigung zu Modell

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid ...

Utilizing pHluorin-tagged Receptors to Monitor Subcellular Localization and Trafficking

Understanding membrane protein trafficking, assembly, and expression requires an approach that differentiates between those residing in intracellular organelles and those localized on the plasma membrane. Traditional fluorescence-based measurements lack the capability to distinguish membrane proteins residing in different organelles. Cutting edge methodologies transcend traditional methods by coupling pH-sensitive fluorophores with total internal reflection fluorescence microscopy (TIRFM). TIRF illumination excites the sample up to approximately 150 nm from the glass-sample interface, thus decreasing background, increasing the signal to noise ratio, and enhancing resolution. The excitation volume in TIRFM encompasses the plasma membrane and nearby organelles such as the peripheral ER. Superecliptic pHluorin (SEP) is a pH sensitive version of GFP. Genetically encoding SEP into the extracellular domain of a membrane protein of interest positions the fluorophore on the luminal side of the ER and in the extracellular region of the cell. SEP is fluorescent when the pH is greater than 6, but remains in an off state at lower pH values. Therefore, receptors tagged with SEP fluoresce when residing in the endoplasmic reticulum (ER) or upon insertion in the plasma membrane (PM) but not when confined to a trafficking vesicle or other organelles such as the Golgi. The extracellular pH can be adjusted to dictate the fluorescence of receptors on the plasma membrane. The difference in fluorescence between TIRF images at neutral and acidic extracellular pH for the same cell corresponds to a relative number of receptors on the plasma membrane. This allows a simultaneous measurement of intracellular and plasma membrane resident receptors. Single vesicle insertion events can also be measured when the extracellular pH is neutral, corresponding to a low pH trafficking vesicle fusing with the plasma membrane and transitioning into a fluorescent state. This versatile technique can be exploited to study localization, expression, and trafficking of membrane proteins.

Labeling the extracellular domain of a membrane protein with a pH sensitive fluorophore, superecliptic pHluorin (SEP), allows subcellular localization, expression, and trafficking to be determined. Imaging SEP-labeled proteins with total internal reflection fluorescence microscopy (TIRFM) enables the quantification of protein levels in the peripheral ER and plasma membrane.

pHluorin-getaggt Receptors Verwendung zu überwachen subzelluläre Lokalisierung und Handel

Understanding membrane protein trafficking, assembly, and expression requires an approach that differentiates between those residing in intracellular ...

Imaging Intermediate Filaments and Microtubules with 2-dimensional Direct Stochastic Optical Reconstruction Microscopy

The cytoskeleton, composed of actin microfilaments, microtubules, and intermediate filaments (IF), plays a key role in the control of cell shape, polarity, and motility. The organization of the actin and microtubule networks has been extensively studied but that of IFs is not yet fully characterized. IFs have an average diameter of 10 nm and form a network extending throughout the cell cytoplasm. They are physically associated with actin and microtubules through molecular motors and cytoskeletal linkers. This tight association is at the heart of the regulatory mechanisms that ensure the coordinated regulation of the three cytoskeletal networks required for most cell functions. It is therefore crucial to visualize IFs alone and also together with each of the other cytoskeletal networks. However, IF networks are extremely dense in most cell types, especially in glial cells, which makes its resolution very difficult to achieve with standard fluorescence microscopy (lateral resolution of ~250 nm). Direct STochastic Optical Reconstruction Microscopy (dSTORM) is a technique allowing a gain in lateral resolution of one order of magnitude. Here, we show that lateral dSTORM resolution is sufficient to resolve the dense organization of the IF networks and, in particular, of IF bundles surrounding microtubules. Such tight association is likely to participate in the coordinated regulation of these two networks and may, explain how vimentin IFs template and stabilize microtubule organization as well as could influence microtubule dependent vesicular trafficking. More generally, we show how the observation of two cytoskeletal components with dual-color dSTORM technique brings new insight into their mutual interaction.

The overall goal of this methodology is to give the optimal experimental conditions from sample preparation to image acquisition and reconstruction in order to perform 2D dual color dSTORM images of microtubules and intermediate filaments in fixed cells

Imaging-Intermediate Filamenten und Mikrotubuli mit 2-dimensionale direkte stochastische optische Rekonstruktion Mikroskopie

The cytoskeleton, composed of actin microfilaments, microtubules, and intermediate filaments (IF), plays a key role in the control of cell shape, ...

A Proximal Culture Method to Study Paracrine Signaling Between Cells

Intercellular interactions play an important role in many biological processes, including tumor progression, immune responses, angiogenesis, and development. Paracrine or juxtacrine signaling mediates such interactions. The use of a conditioned medium and coculture studies are the most common methods to discriminate between these two types of interactions. However, the effect of localized high concentrations of secreted factors in the microenvironment during the paracrine interactions is not accurately recapitulated by conditioned medium and, thus, may lead to imprecise conclusions. To overcome this problem, we have devised a proximal culture method to study paracrine signaling. The two cell types are grown on either surface of a 10 &#181;m-thick polycarbonate membrane with 0.4 &#181;m pores. The pores allow the exchange of secreted factors and, at the same time, inhibit juxtacrine signaling. The cells can be collected and lysed at the endpoint to determine the effects of the paracrine signaling. In addition to allowing for localized concentration gradients of secreted factors, this method is amenable to experiments involving prolonged periods of culture, as well as the use of inhibitors. While we use this method to study the interactions between ovarian cancer cells and the mesothelial cells they encounter at the site of metastasis, it can be adapted to any two adherent cell types for researchers to study paracrine signaling in various fields, including tumor microenvironment, immunology, and development.

Paracrine and juxtacrine cellular interactions play an important role in many biological processes, including tumor progression, immune responses, angiogenesis, and development. Here, a proximal culture method is used to study paracrine signaling where the localized concentrations of the secreted factors are maintained while preventing direct cellular contact.