Die Autoren bedanken sich bei Shawna Rideout-Gros und Alexandra Garces für ihre Hilfe bei der Pflege der Tiere zu danken, und Wu Ping für ihre technische Unterstützung. Unterstützung für diese Arbeit wurde von den National Institutes of Health unter dem Förderkennzeichen nicht zur Verfügung gestellt. EB003268, Kanada und die Forschung Stühle Programm.

1. Ultraschall-und MRT-Setup Eine MRT-kompatiblen Drei-Achsen-fokussiertem Ultraschall-System wurde in dieser Studie verwendet (FUS Instruments, Inc., Toronto, Ontario, Kanada). Zwei verschiedene Ultraschallwandler wurden verwendet: ein In-House gebaut 551,5 kHz sphärisch fokussierter Wandler (Krümmungsradius = 60 mm, Außendurchmesser = 75 mm, Innendurchmesser = 20 mm) und ein 1,503 MHz, 8-Sektor-Array mit integrierter PZT Hydrophon (Imasonic Inc., Voray-sur-L&#39;Orgnon, Frankreich) als ein einziges Element sphärisch konzentriert Wandler (FN = 0,8, Blende = 10 cm) angetrieben wird. Eine MRT-kompatiblen Empfänger 8 PVDF wurde eingesetzt, um akustische Emissionen aufnehmen, wenn die 551,5 kHz Wandler verwendet wurde. Wenn andere Geräte verwendet wird, werden die folgenden vorgeschlagen: <ol><li> Wählen eines geeigneten, kalibriert Ultraschallwandler mit einer Mittenfrequenz im Bereich von 0,25 MHz -1,5 MHz und einem f-Wert (Krümmungsradius / Apertur) von 1 oder weniger. </li><li> Setzen Sie ein Wasserbad fiullt mit warmem, entgast, entionisiertem Wasser auf dem Bett von einem 1,5 T oder 3 T MR. Das Wasserbad sollte eine Top-Platte, die die Tiere aufnehmen kann. Montieren Sie den Ultraschallwandler im Tank auf einer MRT-kompatibel Drei-Achsen-Positionierung der Bühne oder System 9, mit Blick auf die Wasseroberfläche. </li><li> Führen Sie das Kabel mit dem Wandler Ultraschall Fahren Ausrüstung durch ein Eindringen Panel. </li><li> Generieren Sie den Schallkopf Ansteuersignal mit einem Funktionsgenerator und Leistungsverstärker. Verwenden Sie eine externe Anpassungsschaltung, um die reflektierte elektrische Energie zu minimieren. </li><li> Das Wissen des Wandlers Brennweite, platzieren Sie den Schallkopf Schwerpunkt an der Wasseroberfläche und beschallen die Wasseroberfläche, um eine sichtbare Wasserfontäne zu erzeugen. Die Schritte 1.6 und 1.7 beschrieben, wie Sie den Fokus mithilfe der generierten Wasserfontäne registrieren. Eine genauere Methode zur Lokalisierung des Fokus, die Beschallung einer Wärme absorbierenden Gel Imaging und die daraus resultierende Temperaturerhöhung in den Fokus mit der MRT beinhaltet, kann in 9 gefunden werden &lt;/ Sup&gt;. </li><li> Markieren Sie die Stelle des Fokus mit Hilfe eines Markers, der sichtbar sein auf den MR-Bildern werden. Dies kann unter Verwendung einer Platte mit einem zentralen Loch, das mit Wasser zu füllen, wenn über den Fokus gebracht werden. Die mit Wasser gefüllten Loch sichtbar auf dem MRT und Schwerpunkt-Koordinaten in zwei Ebenen zu schaffen, während die Koordinate in der axialen Richtung des Aufnehmers von der Wasseroberfläche bestimmt werden kann. </li><li> Mit einem 3-Ebene Lokalisierungsbilder-Sequenz, Bild den Fokus Marker und Aufzeichnung der Position des Fokus in der MR-Koordinatensystem. </li><li> Um akustische Emissionen zu überwachen, montieren ein MR-kompatibler Hydrophon 8, die als passive Kavitation Detektor (PKD) im Wasserbad bei dem Wandler Fokus gerichtet eingesetzt wird, oder verwenden Sie einen Wandler mit integrierter Hydrophon. </li><li> Führen Sie die PCD-Kabel mit einem Rahmen-Karte, die ausreichend schnell, um Ausbrüche von bis zu 10 ms erfassen PRFs bei bis zu 2 Hz (z. B. ATS460, AlazarTech, Pointe-Claire, Quebec, Kanada) ist. Die Kabel müssen an die Pene geerdet werdentration Panel oder HF-Abschirmung Rauschen zu verringern. </li></ol> 2. Tierische Vorbereitung <ol><li> Betäuben die Tiere mit Isofluran-Gas. Da Isofluoran wirkt sich auf Störungen BBB 10, sind die Tiere ausgeschaltet werden die Gas 10 Minuten vor dem Beginn des Experiments entnommen. Platz okularen Schmiermittel Salbe in jedes Auge zu Beginn der Anästhesie, um die Hornhaut vor Austrocknung oder anderen Verletzungen zu schützen. </li><li> Mit einem elektrischen Rasierer rasieren das Fell von der Spitze des Tieres Kopf und Hals, dann nehmen Sie das übrige Fell mit einer Enthaarungscreme (zB Nair, Church &amp; Dwight Co., Princeton, NJ, USA) und spülen Sie die Kopfhaut mit milder Seife und Wasser. </li><li> Bereiten Sie den Schwanz mit einem Betadin Haut durch ein Peeling bridine Wäsche gefolgt. Eine abschließende wipedown mit Alkohol, um die Schwanzvene zu visualisieren. </li><li> Legen Sie eine 22-Gauge-Katheter mit 3-Wege-Hahn in die Schwanzvene und bündig mit einer Heparin / Kochsalz-Gemisch (33 U / ml) zur Gerinnselbildung verhindernin dem Katheter. </li><li> Deliver Injektionsnarkosemittel (40-50 mg / kg Ketamin, 10 mg / kg Xylazin) durch intramuskuläre Injektion, und entfernen Sie das Tier aus der Isofluoran. </li><li> Setzen Sie den narkotisierten Tier in Rückenlage auf dem Ultraschall-Ortungssystem mit der Oberseite des Kopfes Kontakt mit dem Wasserbad durch ein Loch in der oberen Platte (Abb. 1). Eine kleine Menge Ultraschallgel vielleicht an die Spitze der den Kopf des Tieres, um die Chance der eingeschlossenen Luftblasen zu minimieren angewendet. </li><li> Band die Beine an dem Positionierungssystem. Der Kopf kann an ihrem Platz gehalten werden, entweder mit einem Biss bar, wenn verfügbar, oder ein Band gelegt fest über dem Kinn. </li><li> Decken Sie das Tier mit einem Handtuch und Decke zirkulierende Wasser, um es warm zu halten. </li></ol> 3. Zielauswahl <ol><li> Erwerben Sie Grundlinie axiale T 2-gewichtete und T 1-gewichteten MR-Bilder des Gehirns. Wenn Sie mit einem 1,5 T MRT und engagierten kopfgroßen HF-Spule empfangen Oberfläche, geeignet scein Parameter sein könnte: T 2-gewichteten: FSE, TE = 60 ms, TR = 2000 ms T 1 gewichtete: FSE, TE = 10 ms, TR = 500 ms </li><li> Wählen Sie das Ziel aus dem T 2-gewichteten Scans, die Vermeidung und die Ventrikel des Gehirns Mittellinie, und zum Auswählen einer mittleren Tiefe des Gehirns. </li><li> Setzen Sie den Schallkopf Fokus auf den Zielort. </li></ol> 4. Mikroblasen-Vorbereitung Definity Mikrobläschen (Lantheus Medical Imaging, MA, USA) werden von mehreren Gruppen für Mikroblasen vermittelte FUS induziert BBBD 2,5,7 verwendet. Geeignete Dosierungen für andere Typen von Mikrobläschen in der Literatur 11,12 gefunden werden. <ol><li> Aktivieren Sie die Definity Mikrobläschen und langsam erarbeiten ein kleines Volumen in einer 1 ml Spritze mit einer 18-Gauge-Nadel. </li><li> Entfernen eingeschlossene Luft aus der Spritze durch vorsichtiges Bewegen des Kolbens hin und her. Tippen Sie nicht auf die Spritze, da dies die Blasen brechen können. </li><li> Verdünnen Sie die Definity im normalen<html> Kochsalzlösung in einem Verhältnis von 10:1 Kochsalzlösung Definty durch langsames Einspritzen der erforderlichen Menge von Definity in eine Spritze mit Kochsalzlösung. Wenn eine Infusion Lieferung verwendet wird, kann die Definity weiter verdünnt werden, bis 50:1 oder 100:1. </li><li> Vorsichtig auf den Kopf, um die Spritze gründlich mischen die Definity und Kochsalzlösung, bis eine gleichmäßige Optik erreicht wird. Vorsichtiges Schwenken der Spritze unmittelbar vor der Injektion kann auch erforderlich sein, wenn die Bläschen angefangen haben zu schweben aus der Suspension. </li><li> Berechnen Sie die erforderliche Dosis-Volumen auf 0,02 ml / kg Definity oder 0,2 ml / kg der Lösung (bei 10:1 Verdünnung) basiert. </li></ol> 5. Ultraschall-Abgabesystem <ol><li> Stellen Sie die Sonikationsparameter mit niedrigem Tastverhältnis platzt, nicht Dauerstrich sonications. Entsprechende Sonikationsparameter bei 0,5 MHz sind 0,23 MPa Druck in situ, 10 ms platzt bei 1 Hz PRF, 2 min. Insgesamt Beschallungszeit. Bei 1,5 MHz geeignete in-situ-Druck fallen um 0,45-0,5 MPa. </li></ol>_content &quot;&gt; Geeignete Drücke bei verschiedenen Frequenzen kann unter Verwendung eines mechanischen Index von 0,46 13 aufzunehmen. <ol start="2"><li> Prüfen Sie, ob der Kopf des Tieres noch mit dem Wasser verbunden. </li><li> Injizieren der Mikroblasen langsam in die Schwanzvene Katheter und bündig mit 0,5 ml normaler Kochsalzlösung. Beginnen Sie mit der Beschallung gleichzeitig mit dem Beginn der Einspritzung. </li></ol> 6. MRT-Auswertung der Behandlungsergebnisse <ol><li> Nach der Ultraschallbehandlung, injizieren ein MRT-Kontrastmittel (z. B. 0,2 ml / kg Omniscan, GE Healthcare) über die Schwanzvene Katheter durch eine 0,5 ml Kochsalzlçsung. </li><li> Führen T 1-gewichteter Bildgebung, bis der Kontrast Gipfel ist vorbei. Ultraschallbehandlung Seiten, die erfolgreich gestört wird zeigen größere Steigerung als das umgebende Gewebe. </li><li> Führen T 2-gewichteter Bildgebung, für Ödeme zu überprüfen. High-Signal an den Standorten Beschallung ist ein Hinweis auf Ödeme. </li></ol> 7. VertreterErgebnisse MRI-Kontrastmittel können erfolgreich durch die BBB geliefert werden mittels fokussiertem Ultraschall und Mikrobläschen zirkulieren. Abbildung 2 zeigt typische Pre-und Post-FUS T 1-w Bildern. 2B zeigt einen kontrastverstärkten (CE) T 1-w-Bild mit deutlichen Schwerpunkt Öffnungen in vier beschallten Standorten. Ultraschallbehandlung Standorten 1 und 2 zeigen besonders hell Verbesserung. In 3 Stellen 1 und 2 ist auch ersichtlich, mit T 2-w hohes Signal entspricht, der angibt, Ödeme werden. Das Ausmaß der T 2-w Ödem kann manchmal leichter sichtbar gemacht werden auf sagittalen Schichten. Abbildung 4 zeigt CE-T 1-w und T 2-w sagittal durch Ultraschall 1 und 3 Standorten. Ödem ist sichtbar am Standort 1 Standort, aber nicht 3. Die Spektralanalyse der aufgenommenen akustischen Emissionen Daten (Abb. 5) kann zeigen, harmonische Emissionen und / oder Sub / ultra harmonische Emissionen, wenn stabile Kavitation auftritt. HarmonICs können auch aus Gewebe Nichtlinearitäten entstehen, während sub ​​und ultraharmonischen-Emissionen kann nur als Folge der Blase 14 Aktivität auftreten. Bei höheren Drücken Breitband-Emissionen angibt inertialen Kavitation kann auch erkannt werden. Diese wurden jedoch größere Mengen von roten Blutkörperchen und Extravasationen Mikroschädigung als sonications ohne Inertial Kavitation 11 in Verbindung gebracht. Die Verwendung höherer Frequenzen Beschallung führt zu lokalisierten Öffnungen aufgrund der kleineren Brennfleckgröße. 6 zeigt, dass höhere Frequenzen verwendet werden, um kleinere Bereiche der Öffnung zu erzeugen. Dies ermöglicht Untersuchung von Wirkungen Mitte Gehirn mit weniger nahe Schädel-Effekte. <img alt="Abbildung 1." src="/files/ftp_upload/3555/3555fig1.jpg" /> Abbildung 1. Versuchsaufbau. <spein class = &quot;pdflinebreak&quot;&gt; <img alt="Abbildung 2." src="/files/ftp_upload/3555/3555fig2.jpg" /> Abbildung 2. Pre (links) und nach (rechts) Behandlung T 1-w-Bilder durch ein Rattenhirn zeigen Erweiterung an vier Standorten Beschallung. <img alt="Abbildung 3." src="/files/ftp_upload/3555/3555fig3.jpg" /> Abbildung 3. Pre (links) und nach (rechts) Behandlung T 2-w-Bilder durch ein Rattenhirn (dasselbe Tier wie Abb. 2) zeigt T 2-w Ödeme bei Beschallung Standorten 1 und 2. <img alt="Abbildung 4." src="/files/ftp_upload/3555/3555fig4.jpg" /> Abbildung 4. Nachbehandlung sagittale T 1-w (links) und T 2-w (rechts) Bilder von der gleichen Rattenhirn wie Feigen. 2 und 3. Die Öffnung am Standort 1 (links) korreliert mit T 2-w Ödem (rechts). Lage 3 zeigt Öffnung (links), aber keine T 2-w Ödem. </p&gt; <img alt="Abbildung 5." src="/files/ftp_upload/3555/3555fig5.jpg" /> Abbildung 5. Frequenzspektrum von Daten während eines einzigen 10 ms Burst bei 551,5 kHz erfasst. Die Grundfrequenz (f 0) sowie Oberwellen (2 f 0) und Sub / ultraharmonics (0,5 f 0, 1,5 f 0) sichtbar sind. <img alt="Abbildung 6." src="/files/ftp_upload/3555/3555fig6.jpg" /> Abbildung 6. Nachbehandlung CE-T 1-w axiale (links) und sagittaler (rechts) Bilder von einem Rattenhirn an vier Standorten auf 1,503 MHz beschallt. BBB Öffnungen bei dieser Frequenz zu sehen sind, um mehr lokalisiert.

<ol>
	<li>Kinoshita, M., McDannold, N., Jolesz, F. A., Hynynen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+localized+delivery+of+Herceptin+to+the+mouse+brain+by+MRI-guided+focused+ultrasound-induced+blood-brain+barrier+disruption.">Noninvasive localized delivery of Herceptin to the mouse brain by MRI-guided focused ultrasound-induced blood-brain barrier disruption.</a> Proc. Natl. Acad. Sci. U.S.A. 103, 11719-11723 (2006).</li><li>Jord&#227;o, J. F., Ayala-Grosso, C. A., Markham, K., Huang, Y., Chopra, R., McLaurin, J., Hynynen, K., Aubert, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibodies+targeted+to+the+brain+with+image-guided+focused+ultrasound+reduces+amyloid-beta+plaque+load+in+the+TgCRND8+mouse+model+of+Alzheimer&#39;s+disease.">Antibodies targeted to the brain with image-guided focused ultrasound reduces amyloid-beta plaque load in the TgCRND8 mouse model of Alzheimer&#39;s disease.</a> PLoS One. 5 (5), e10549-e10549 (2010).</li><li>Liu, H. -. L., Hua, M. -. Y., Chen, P. -. Y., Chu, P. -. C., Pan, C. -. H., Yang, H. -. W., Huang, C. -. Y., Wang, J. -. J., Yen, T. -. C., Wei, K. -. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood-brain+barrier+disruption+with+focused+ultrasound+enhances+delivery+of+chemotherapeutic+drugs+for+glioblastoma+treatment.">Blood-brain barrier disruption with focused ultrasound enhances delivery of chemotherapeutic drugs for glioblastoma treatment.</a> Radiology. 255, 415-425 (2010).</li><li>Hynynen, K., McDannold, N., Vykhodtseva, N., Jolesz, F. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+MR+imaging-guided+focal+opening+of+the+blood-brain+barrier+in+rabbits.">Noninvasive MR imaging-guided focal opening of the blood-brain barrier in rabbits.</a> Radiology. 220, 640-646 (2001).</li><li>Choi, J. J., Wang, S., Tung, Y. -. S., Morrison, B., Konofagou, E. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecules+of+various+pharmacologically-relevant+sizes+can+cross+the+ultrasound-induced+blood-brain+barrier+opening+in+vivo.">Molecules of various pharmacologically-relevant sizes can cross the ultrasound-induced blood-brain barrier opening in vivo.</a> Ultrasound Med. Biol. 36, 58-67 (2010).</li><li>Pardridge, W. 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+blood-brain+barrier:+bottleneck+in+brain+drug+development.">The blood-brain barrier: bottleneck in brain drug development.</a> NeuroRx. 2, 3-14 (2005).</li><li>Bing, K. F., Howles, G. P., Qi, Y., Palmeri, M. L., Nightingale, 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=Blood-brain+barrier+&#40;BBB&#41;+disruption+using+a+diagnostic+ultrasound+scanner+and+Definity+in+mice.">Blood-brain barrier &#40;BBB&#41; disruption using a diagnostic ultrasound scanner and Definity in mice.</a> Ultrasound Med. Biol. 35, 1298-1308 (2009).</li><li>O'Reilly, M. A., Hynynen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+PVDF+receiver+for+ultrasound+monitoring+of+transcranial+focused+ultrasound+therapy.">A PVDF receiver for ultrasound monitoring of transcranial focused ultrasound therapy.</a> IEEE Trans. Biomed. Eng. 57, 2286-2294 (2010).</li><li>Chopra, R., Curiel, L., Staruch, R., Morrison, L., Hynynen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+MRI-compatible+system+for+focused+ultrasound+experiments+in+small+animal+models.">An MRI-compatible system for focused ultrasound experiments in small animal models.</a> Med. Phys. 36, 1867-1874 (2009).</li><li>McDannold, N., Zhang, Y., Vykhodtseva, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood-Brain+Barrier+Disruption+and+Vascular+Damage+Induced+by+Ultrasound+Bursts+Combined+with+Microbubbles+can+be+Influenced+by+Choice+of+Anesthesia+Protocol.">Blood-Brain Barrier Disruption and Vascular Damage Induced by Ultrasound Bursts Combined with Microbubbles can be Influenced by Choice of Anesthesia Protocol.</a> Ultrasound Med. Biol. , (2011).</li><li>McDannold, N., Vykhodtseva, N., Hynynen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+disruption+of+the+blood-brain+barrier+with+focused+ultrasound:+association+with+cavitation+activity.">Targeted disruption of the blood-brain barrier with focused ultrasound: association with cavitation activity.</a> Phys. Med. Biol. 51, 793-807 (2006).</li><li>Yang, F. -. Y., Liu, S. -. H., Ho, F. -. M., Chang, C. -. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+ultrasound+contrast+agent+dose+on+the+duration+of+focused-ultrasound-induced+blood-brain+barrier+disruption.">Effect of ultrasound contrast agent dose on the duration of focused-ultrasound-induced blood-brain barrier disruption.</a> J. Acoust. Soc. Am. 126, 3344-3349 (2009).</li><li>McDannold, N., Vykhodtseva, N., Hynynen, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood-brain+barrier+disruption+induced+by+focused+ultrasound+and+circulating+preformed+microbubbles+appears+to+be+characterized+by+the+mechanical+index.">Blood-brain barrier disruption induced by focused ultrasound and circulating preformed microbubbles appears to be characterized by the mechanical index.</a> Ultrasound Med. Biol. 34, 834-840 (2008).</li><li>Neppiras, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acoustic+Cavitation.">Acoustic Cavitation.</a> Physics Reports (Review Section of Physics Letters). 61, 159-251 (1980).</li><li>O&#39;Reilly, M. A., Huang, Y., Hynynen, 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+impact+of+standing+wave+effects+on+transcranial+focused+ultrasound+disruption+of+the+blood-brain+barrier+in+a+rat+model.">The impact of standing wave effects on transcranial focused ultrasound disruption of the blood-brain barrier in a rat model.</a> Phys. Med. Biol. 55, 5251-5267 (2010).</li></ol>

K. und R. Hynynen Chopra sind Mitbegründer der FUS Instruments, Inc. R. Chopra, A. und K. Waspe Hynynen Aktionäre sind in FUS Instruments, Inc. erhält K. Hynynen Forschungsförderung von FUS Instruments, Inc.

Vorbereitung der Tiere und Mikrobläschen sind die kritischsten Aspekte dieses Verfahrens. Das Haar auf dem Kopf des Tieres muss vollständig entfernt werden, um zu vermeiden Dämpfung des Ultraschalls. Die BBB unter Isofluran Anästhetikum kann unterbrochen werden, jedoch wird es schwierig, konsistente Öffnung zu erreichen. Die Mikrobläschen immer sollte auch mit Sorgfalt und kleinen Spurweite gehandhabt werden, so großen Durchmesser Nadeln verwendet bei der Aufstellung, um zu vermeiden,...

<table border="1"><tbody><tr><td> Name des Reagenzes </td><td> Firma </td><td> Katalog-Nummer </td></tr><tr><td> Small Animal fokussiertem Ultraschall-System </td><td> FUS Instruments, Inc. </td><td> RK-100 </td></tr><tr><td> Definity </td><td> Lantheus Medical Imaging </td><td></td></tr><tr><td> Omniscan </td><td> GE Healthcare </td><td></td></tr></tbody></table>

mri-guided disruption of the blood-brain barrier using transcranial focused ultrasound in a rat model

Fokussiertem Ultraschall (FUS) Störung der Blut-Hirn-Schranke (BHS) ist ein zunehmend untersuchte Methode zur Umgehung des BBB 05.01. Die BBB ist ein wesentliches Hindernis für pharmazeutische Behandlungen von Erkrankungen des Gehirns, wie sie den Durchtritt von Molekülen aus dem Gefäßsystem begrenzt in das Gehirngewebe, um Moleküle weniger als etwa 500 Da in der Größe 6. FUS BBB induzierten Störungen (BBBD) ist eine vorübergehende, reversible 4 und hat einen Vorteil gegenüber chemischen Mitteln zu induzieren, indem sie stark lokalisierten BBBD. FUS induzierte BBBD stellt ein Mittel zur Untersuchung der Wirkungen einer Vielzahl von therapeutischen Mitteln auf das Gehirn, die sonst nicht lieferbar sein, um das Gewebe in einer ausreichenden Konzentration. Während eine Vielzahl von Ultraschall-Parameter bewährt haben zu stören die BBB 2,5,7, gibt es mehrere wichtige Schritte im experimentellen Verfahren zur erfolgreichen Störungen genaue Ausrichtung zu gewährleisten. Dieses Protokollol beschrieben, wie Sie zu erreichen unter MRT-FUS in einem Rattenmodell BBBD induziert wird, mit einem Schwerpunkt auf der kritischen Tier Vorbereitung und Mikroblasen-Handling-Schritte des Experiments.

Watch this Scientific Journal Video about MRI-guided Disruption of the Blood-brain Barrier using Transcranial Focused Ultrasound in a Rat Model at JoVE.com

MRI-guided Disruption of the Blood-brain Barrier using Transcranial Focused Ultrasound in a Rat Model

Mikroblasen-vermittelte fokussiertem Ultraschall Störung der Blut-Hirn-Schranke (BHS) ist eine vielversprechende Technik zur nicht-invasiven gezielten Verabreichung von Medikamenten im Gehirn<sup&gt; 3.1</sup&gt;. Dieses Protokoll beschreibt die experimentelle Verfahren für die MRI-geführten transkranielle BBB Störung in einem Rattenmodell.

MRI-geführten Störung der Blut-Hirn-Schranke mit Hilfe der transkraniellen fokussiertem Ultraschall in einem Rattenmodell

Focused ultrasound (FUS) disruption of the blood-brain barrier (BBB) is an increasingly investigated technique for circumventing the BBB1-5. The BBB is a ...

mri-guided-disruption-blood-brain-barrier-using-transcranial-focused

Research

JoVE Journal

Medicine

17.8K Aufrufe.  Sunnybrook Research Institute. Mikroblasen-vermittelte fokussiertem Ultraschall Störung der Blut-Hirn-Schranke (BHS) ist eine vielversprechende Technik zur nicht-invasiven gezielten Verabreichung von Medikamenten im Gehirn 3.1. Dieses Protokoll beschreibt die experimentelle Verfahren für die MRI-geführten transkranielle BBB Störung in einem Rattenmodell.

Serie: MRI-guided Disruption of the Blood-brain Barrier using Transcranial Focused Ultrasound in a Rat Model

Multi-modal Imaging of Angiogenesis in a Nude Rat Model of Breast Cancer Bone Metastasis Using Magnetic Resonance Imaging, Volumetric Computed Tomography and Ultrasound

Angiogenesis is an essential feature of cancer growth and metastasis formation. In bone metastasis, angiogenic factors are pivotal for tumor cell proliferation in the bone marrow cavity as well as for interaction of tumor and bone cells resulting in local bone destruction. Our aim was to develop a model of experimental bone metastasis that allows in vivo assessment of angiogenesis in skeletal lesions using non-invasive imaging techniques.
For this purpose, we injected 105 MDA-MB-231 human breast cancer cells into the superficial epigastric artery, which precludes the growth of metastases in body areas other than the respective hind leg1. Following 25-30 days after tumor cell inoculation, site-specific bone metastases develop, restricted to the distal femur, proximal tibia and proximal fibula1. Morphological and functional aspects of angiogenesis can be investigated longitudinally in bone metastases using magnetic resonance imaging (MRI), volumetric computed tomography (VCT) and ultrasound (US).
MRI displays morphologic information on the soft tissue part of bone metastases that is initially confined to the bone marrow cavity and subsequently exceeds cortical bone while progressing. Using dynamic contrast-enhanced MRI (DCE-MRI) functional data including regional blood volume, perfusion and vessel permeability can be obtained and quantified2-4. Bone destruction is captured in high resolution using morphological VCT imaging. Complementary to MRI findings, osteolytic lesions can be located adjacent to sites of intramedullary tumor growth. After contrast agent application, VCT angiography reveals the macrovessel architecture in bone metastases in high resolution, and DCE-VCT enables insight in the microcirculation of these lesions5,6. US is applicable to assess morphological and functional features from skeletal lesions due to local osteolysis of cortical bone. Using B-mode and Doppler techniques, structure and perfusion of the soft tissue metastases can be evaluated, respectively. DCE-US allows for real-time imaging of vascularization in bone metastases after injection of microbubbles7.
In conclusion, in a model of site-specific breast cancer bone metastases multi-modal imaging techniques including MRI, VCT and US offer complementary information on morphology and functional parameters of angiogenesis in these skeletal lesions.

In the pathogenesis of bone metastasis, angiogenesis is a crucial process and therefore represents a target for imaging and therapy. Here, we present a rat model of site-specific breast cancer bone metastasis and describe strategies to non-invasively image angiogenesis in vivo using magnetic resonance imaging, volumetric computed tomography and ultrasound.

Multimodale Bildgebung von Angiogenese in einem Nude Rattenmodell der Brustkrebs Knochenmetastasen mittels Magnetresonanztomographie, volumetrische Computertomographie und Ultraschall

Angiogenesis is an essential feature of cancer growth and metastasis formation. In bone metastasis, angiogenic factors are pivotal for tumor cell ...

Forschung

Medizin

Rat Model of Blood-brain Barrier Disruption to Allow Targeted Neurovascular Therapeutics

Endothelial cells with tight junctions along with the basement membrane and astrocyte end feet surround cerebral blood vessels to form the blood-brain barrier1. The barrier selectively excludes molecules from crossing between the blood and the brain based upon their size and charge. This function can impede the delivery of therapeutics for neurological disorders. A number of chemotherapeutic drugs, for example, will not effectively cross the blood-brain barrier to reach tumor cells2. Thus, improving the delivery of drugs across the blood-brain barrier is an area of interest.
The most prevalent methods for enhancing the delivery of drugs to the brain are direct cerebral infusion and blood-brain barrier disruption3. Direct intracerebral infusion guarantees that therapies reach the brain; however, this method has a limited ability to disperse the drug4. Blood-brain barrier disruption (BBBD) allows drugs to flow directly from the circulatory system into the brain and thus more effectively reach dispersed tumor cells. Three methods of barrier disruption include osmotic barrier disruption, pharmacological barrier disruption, and focused ultrasound with microbubbles. Osmotic disruption, pioneered by Neuwelt, uses a hypertonic solution of 25% mannitol that dehydrates the cells of the blood-brain barrier causing them to shrink and disrupt their tight junctions. Barrier disruption can also be accomplished pharmacologically with vasoactive compounds such as histamine5 and bradykinin6. This method, however, is selective primarily for the brain-tumor barrier7. Additionally, RMP-7, an analog of the peptide bradykinin, was found to be inferior when compared head-to-head with osmotic BBBD with 25% mannitol8. Another method, focused ultrasound (FUS) in conjunction with microbubble ultrasound contrast agents, has also been shown to reversibly open the blood-brain barrier9. In comparison to FUS, though, 25% mannitol has a longer history of safety in human patients that makes it a proven tool for translational research10-12.
In order to accomplish BBBD, mannitol must be delivered at a high rate directly into the brain's arterial circulation. In humans, an endovascular catheter is guided to the brain where rapid, direct flow can be accomplished. This protocol models human BBBD as closely as possible. Following a cut-down to the bifurcation of the common carotid artery, a catheter is inserted retrograde into the ECA and used to deliver mannitol directly into the internal carotid artery (ICA) circulation. Propofol and N2O anesthesia are used for their ability to maximize the effectiveness of barrier disruption13. If executed properly, this procedure has the ability to safely, effectively, and reversibly open the blood-brain barrier and improve the delivery of drugs that do not ordinarily reach the brain 8,13,14.

Blood-brain barrier disruption aids the delivery of certain drugs to the brain. Mannitol delivered intra-arterially shrinks cells surrounding blood vessels in order to physically disrupt the barrier.

Rat Modell der Blut-Hirn-Schranke Störung zu Neurovascular Therapeutics Gezielte zulassen

Endothelial cells with tight junctions along with the basement membrane and astrocyte end feet surround cerebral blood vessels to form the blood-brain ...

A Model of Chronic Nutrient Infusion in the Rat

Chronic exposure to excessive levels of nutrients is postulated to affect the function of several organs and tissues and to contribute to the development of the many complications associated with obesity and the metabolic syndrome, including type 2 diabetes. To study the mechanisms by which excessive levels of glucose and fatty acids affect the pancreatic beta-cell and the secretion of insulin, we have established a chronic nutrient infusion model in the rat. The procedure consists of catheterizing the right jugular vein and left carotid artery under general anesthesia; allowing a 7-day recuperation period; connecting the catheters to the pumps using a swivel and counterweight system that enables the animal to move freely in the cage; and infusing glucose and/or Intralipid (a soybean oil emulsion which generates a mixture of approximately 80% unsaturated/20% saturated fatty acids when infused with heparin) for 72 hr. This model offers several advantages, including the possibility to finely modulate the target levels of circulating glucose and fatty acids; the option to co-infuse pharmacological compounds; and the relatively short time frame as opposed to dietary models. It can be used to examine the mechanisms of nutrient-induced dysfunction in a variety of organs and to test the effectiveness of drugs in this context.

A protocol for chronic infusions of glucose and Intralipid in rats is described. This model can be used to study the impact of nutrient excess on organ function and physiological parameters.

Ein Modell der chronischen Nährstoff Infusion in der Ratte

Chronic exposure to excessive levels of nutrients is postulated to  affect the function of several organs and tissues and to contribute to the  ...

Stretch in Brain Microvascular Endothelial Cells (cEND) as an In Vitro Traumatic Brain Injury Model of the Blood Brain Barrier

Due to the high mortality incident brought about by traumatic brain injury (TBI), methods that would enable one to better understand the underlying mechanisms involved in it are useful for treatment. There are both in vivo and in vitro methods available for this purpose. In vivo models can mimic actual head injury as it occurs during TBI. However, in vivo techniques may not be exploited for studies at the cell physiology level. Hence, in vitro methods are more advantageous for this purpose since they provide easier access to the cells and the extracellular environment for manipulation.
Our protocol presents an in vitro model of TBI using stretch injury in brain microvascular endothelial cells. It utilizes pressure applied to the cells cultured in flexible-bottomed wells. The pressure applied may easily be controlled and can produce injury that ranges from low to severe. The murine brain microvascular endothelial cells (cEND) generated in our laboratory is a well-suited model for the blood brain barrier (BBB) thus providing an advantage to other systems that employ a similar technique. In addition, due to the simplicity of the method, experimental set-ups are easily duplicated. Thus, this model can be used in studying the cellular and molecular mechanisms involved in TBI at the BBB.

Stretch in Brain Microvascular Endothelial Cells cEND as an In Vitro Traumatic Brain Injury Model of the Blood Brain Barrier

In vitro traumatic brain injury models are being developed to reproduce in vivo brain deformation. Stretch-induced injury has been employed for astrocytes, neurons, glial cells, aortic, and brain endothelial cells. However, our system uses a blood brain barrier (BBB) model that possesses properties constituting a legitimate model of the BBB to establish an in vitro&#160;TBI model.

Stretchlimousine in Gehirn mikrovaskulären Endothelzellen (CEND) als<em&gt; In Vitro</em&gt; Traumatische Hirnverletzung Modell der Blut-Hirn-Schranke

Due to the high mortality incident brought about by traumatic brain injury (TBI), methods that would enable one to better understand the underlying ...

Setting-up an In Vitro Model of Rat Blood-brain Barrier (BBB): A Focus on BBB Impermeability and Receptor-mediated Transport

The blood brain barrier (BBB) specifically regulates molecular and cellular flux between the blood and the nervous tissue. Our aim was to develop and characterize a highly reproducible rat syngeneic in vitro model of the BBB using co-cultures of primary rat brain endothelial cells (RBEC) and astrocytes to study receptors involved in transcytosis across the endothelial cell monolayer. Astrocytes were isolated by mechanical dissection following trypsin digestion and were frozen for later co-culture. RBEC were isolated from 5-week-old rat cortices. The brains were cleaned of meninges and white matter, and mechanically dissociated following enzymatic digestion. Thereafter, the tissue homogenate was centrifuged in bovine serum albumin to separate vessel fragments from nervous tissue. The vessel fragments underwent a second enzymatic digestion to free endothelial cells from their extracellular matrix. The remaining contaminating cells such as pericytes were further eliminated by plating the microvessel fragments in puromycin-containing medium. They were then passaged onto filters for co-culture with astrocytes grown on the bottom of the wells. RBEC expressed high levels of tight junction (TJ) proteins such as occludin, claudin-5 and ZO-1 with a typical localization at the cell borders. The transendothelial electrical resistance (TEER) of brain endothelial monolayers, indicating the tightness of TJs reached 300 ohm&#183;cm2 on average. The endothelial permeability coefficients (Pe) for lucifer yellow (LY) was highly reproducible with an average of 0.26 &#177;&#160;0.11 x 10-3 cm/min. Brain endothelial cells organized in monolayers expressed the efflux transporter P-glycoprotein (P-gp), showed a polarized transport of rhodamine 123, a ligand for P-gp, and showed specific transport of transferrin-Cy3 and DiILDL across the endothelial cell monolayer. In conclusion, we provide a protocol for setting up an in vitro BBB model that is highly reproducible due to the quality assurance methods, and that is suitable for research on BBB transporters and receptors.

Setting-up an In Vitro Model of Rat Blood-brain Barrier BBB: A Focus on BBB Impermeability and Receptor-mediated Transport

The aim of the present study was to validate the reproducibility of an in vitro BBB model involving a rat syngeneic co-culture of endothelial cells and astrocytes. The endothelial cell monolayer presented high TEER and low LY permeability. Expression of specific TJ proteins, functional responses to inflammation and functionality of transporters and receptors were assessed.

Einrichten einer<em&gt; In-vitro-</em&gt; Modell der Ratte Blut-Hirn-Schranke (BBB): Ein Fokus auf BBB-Undurchlässigkeit und Rezeptor-vermittelten Transport

The blood brain barrier (BBB) specifically regulates molecular and cellular flux between the blood and the nervous tissue. Our aim was to develop and ...

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

We present a protocol for measuring in vivo aortic stiffness in mice using high-resolution ultrasound imaging. Aortic diameter is measured by ultrasound and aortic blood pressure is measured invasively with a solid-state pressure catheter. Blood pressure is raised then lowered incrementally by intravenous infusion of vasoactive drugs phenylephrine and sodium nitroprusside. Aortic diameter is measured for each pressure step to characterize the pressure-diameter relationship of the ascending aorta. Stiffness indices derived from the pressure-diameter relationship can be calculated from the data collected. Calculation of arterial compliance is described in this protocol.
This technique can be used to investigate mechanisms underlying increased aortic stiffness associated with cardiovascular disease and aging. The technique produces a physiologically relevant measure of stiffness compared to ex vivo approaches because physiological influences on aortic stiffness are incorporated in the measurement. The primary limitation of this technique is the measurement error introduced from the movement of the aorta during the cardiac cycle. This motion can be compensated by adjusting the location of the probe with the aortic movement as well as making multiple measurements of the aortic pressure-diameter relationship and expanding the experimental group size.

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

We describe a technique for measuring aortic stiffness from its pressure-diameter relationship in vivo in mice. Aortic diameter is recorded by ultrasound and aortic pressure is measured invasively with a solid-state pressure catheter. Blood pressure is changed incrementally and the resulting diameter is measured.

Mess aufsteigende Aorta Steifigkeit<em&gt; In-vivo-</em&gt; In Mäuse Mit Ultraschall

We present a protocol for measuring in vivo aortic stiffness in mice using high-resolution ultrasound imaging. Aortic diameter is measured by ultrasound ...

Oxygen-Glucose Deprivation and Reoxygenation as an In Vitro Ischemia-Reperfusion Injury Model for Studying Blood-Brain Barrier Dysfunction

Ischemia-Reperfusion (IR) injury is known to contribute significantly to the morbidity and mortality associated with ischemic strokes. Ischemic cerebrovascular accidents account for 80% of all strokes. A common cause of IR injury is the rapid inflow of fluids following an acute/chronic occlusion of blood, nutrients, oxygen to the tissue triggering the formation of free radicals.
Ischemic stroke is followed by blood-brain barrier (BBB) dysfunction and vasogenic brain edema. Structurally, tight junctions (TJs) between the endothelial cells play an important role in maintaining the integrity of the blood-brain barrier (BBB). IR injury is an early secondary injury leading to a non-specific, inflammatory response. Oxidative and metabolic stress following inflammation triggers secondary brain damage including BBB permeability and disruption of tight junction (TJ) integrity.
Our protocol presents an in vitro example of oxygen-glucose deprivation and reoxygenation (OGD-R) on rat brain endothelial cell TJ integrity and stress fiber formation. Currently, several experimental in vivo models are used to study the effects of IR injury; however they have several limitations, such as the technical challenges in performing surgeries, gene dependent molecular influences and difficulty in studying mechanistic relationships. However, in vitro models may aid in overcoming many of those limitations. The presented protocol can be used to study the various molecular mechanisms and mechanistic relationships to provide potential therapeutic strategies. However, the results of in vitro studies may differ from standard in vivo studies and should be interpreted with caution.

Oxygen-Glucose Deprivation and Reoxygenation as an In Vitro Ischemia-Reperfusion Injury Model for Studying Blood-Brain Barrier Dysfunction

Ischemia-Reperfusion (IR) injury is associated with a high rate of morbidity and mortality. The goal of the in vitro model of oxygen-glucose deprivation and reoxygenation (OGD-R) described here is to assess the effects of ischemia reperfusion injury on a variety of cells, particularly in blood-brain barrier (BBB) endothelial cells.

Sauerstoff-Glukose Deprivation und Reoxygenierung als<em&gt; In-vitro-</em&gt; Ischämie-Reperfusion Injury Modell zum Studium der Blut-Hirnschranke Dysfunction

Ischemia-Reperfusion (IR) injury is known to contribute significantly to the morbidity and mortality associated with ischemic strokes. Ischemic ...

MRI-guided dmPFC-rTMS as a Treatment for Treatment-resistant Major Depressive Disorder

Here we outline the protocol for magnetic resonance imaging (MRI) guided repetitive transcranial magnetic stimulation (rTMS) to the dorsal medial prefrontal cortex (dmPFC) in patients with major depressive disorder (MDD). Technicians used a neuronavigation system to process patient MRIs to generate a 3-dimensional head model. The head model was subsequently used to identify patient-specific stimulatory targets. The dmPFC was stimulated daily for 20 sessions. Stimulation intensity was titrated to address scalp pain associated with rTMS. Weekly assessments were conducted on the patients using the Hamilton Rating Scale for Depression (HamD17) and Beck Depression Index II (BDI-II). Treatment-resistant MDD patients achieved significant improvements on both HAMD and BDI-II. Of note, angled, double-cone coil rTMS at 120% resting motor threshold allows for optimal stimulation of deeper midline prefrontal regions, which results in a possible therapeutic application for MDD. One major limitation of the rTMS field is the heterogeneity of treatment parameters across studies, including duty cycle, number of pulses per session and intensity. Further work should be done to clarify the effect of stimulation parameters on outcome. Future dmPFC-rTMS work should include sham-controlled studies to confirm its clinical efficacy in MDD.

Here we outline the procedure for MRI-guided repetitive transcranial magnetic stimulation to the dorsomedial prefrontal cortex as an experimental treatment for major depressive disorder.

MRI-geführte dmPFC-rTMS zur Behandlung behandlungsresistente Major Depressive Disorder

Here we outline the protocol for magnetic resonance imaging (MRI) guided repetitive transcranial magnetic stimulation (rTMS) to the dorsal medial ...

In Vitro Assays to Assess Blood-brain Barrier Mesh-like Vessel Formation and Disruption

Blood-brain barrier (BBB) coverage plays a central role in the homeostasis of the central nervous system (CNS). The BBB is dynamically maintained by astrocytes, pericytes and brain endothelial cells (BECs). Here, we detail methods to assess BBB coverage using single cultures of immortalized human BECs, single cultures of primary mouse BECs, and a humanized triple culture model (BECs, astrocytes and pericytes) of the BBB. To highlight the applicability of the assays to disease states, we describe the effect of oligomeric amyloid-&#946; (oA&#946;), which is an important contributor to Alzheimer&#39;s disease (AD) progression, on BBB coverage. Further, we utilize the epidermal growth factor (EGF) to illuminate the drug screening potential of the techniques. Our results show that single and triple cultured BECs form meshwork-like structures under basal conditions, and that oA&#946; disrupts this cell meshwork formation and degenerates the preformed mesh structures, but EGF blocks this disruption. Thus, the techniques described are important for dissecting fundamental and disease-relevant processes that modulate BBB coverage.

In Vitro Assays to Assess Blood-brain Barrier Mesh-like Vessel Formation and Disruption

Maintaining blood-brain barrier coverage is key for the homeostasis of the central nervous system. This protocol describes in vitro techniques to delineate the fundamental and pathological processes that modulate blood-brain barrier coverage.

In-Vitro- Assays zur Beurteilung der Blut-Hirn-Schranke Mesh-artigen Gefäßbildung und -störung

Blood-brain barrier (BBB) coverage plays a central role in the homeostasis of the central nervous system (CNS). The BBB is dynamically maintained by ...

Improved Method for the Establishment of an In Vitro Blood-Brain Barrier Model Based on Porcine Brain Endothelial Cells

The aim of this protocol presents an optimized procedure for the purification and cultivation of pBECs and to establish in vitro blood-brain barrier (BBB) models based on pBECs in mono-culture (MC), MC with astrocyte-conditioned medium (ACM), and non-contact co-culture (NCC) with astrocytes of porcine or rat origin. pBECs were isolated and cultured from fragments of capillaries from the brain cortices of domestic pigs 5-6 months old. These fragments were purified by careful removal of meninges, isolation and homogenization of grey matter, filtration, enzymatic digestion, and centrifugation. To further eliminate contaminating cells, the capillary fragments were cultured with puromycin-containing medium. When 60-95% confluent, pBECs growing from the capillary fragments were passaged to permeable membrane filter inserts and established in the models. To increase barrier tightness and BBB characteristic phenotype of pBECs, the cells were treated with the following differentiation factors: membrane permeant 8-CPT-cAMP (here abbreviated cAMP), hydrocortisone, and a phosphodiesterase inhibitor, RO-20-1724 (RO). The procedure was carried out over a period of 9-11 days, and when establishing the NCC model, the astrocytes were cultured 2-8 weeks in advance. Adherence to the described procedures in the protocol has allowed the establishment of endothelial layers with highly restricted paracellular permeability, with the NCC model showing an average transendothelial electrical resistance (TEER) of 1249 &#177; 80 &#937; cm2, and paracellular permeability (Papp) for Lucifer Yellow of 0.90 10-6 &#177; 0.13 10-6 cm sec-1 (mean &#177; SEM, n=55). Further evaluation of this pBEC phenotype showed good expression of the tight junctional proteins claudin 5, ZO-1, occludin and adherens junction protein p120 catenin. The model presented can be used for a range of studies of the BBB in health and disease and, with the highly restrictive paracellular permeability, this model is suitable for studies of transport and intracellular trafficking.

Improved Method for the Establishment of an In Vitro Blood-Brain Barrier Model Based on Porcine Brain Endothelial Cells

The aim of the protocol is to present an optimized procedure for the establishment of an in vitro blood-brain barrier (BBB) model based on primary porcine brain endothelial cells (pBECs). The model shows high reproducibility, high tightness, and is suitable for studies of transport and intracellular trafficking in drug discovery.

Verbesserte Methode für die Einrichtung einer In-vitro- Blut - Hirn-Schranke Modell auf porcinen Endothelzellen Gehirnzellen basiert

The aim of this protocol presents an optimized procedure for the purification and cultivation of pBECs and to establish in vitro blood-brain barrier (BBB) ...