Wir wünschen Johnson &amp; Johnson, der TB Alliance, Astra Zeneca, Rib-X und Trius Therapeutics danken für die Bereitstellung von Bedaquilin, PA-824 (pretomanid), AZD5847, radezolid und Tedizolid sind. Brendan Prideaux, Matthew Zimmerman, Stephen Juzwin, Emma Rey-Jurado, Nancy Ruel, Leyan Li und Danielle Weiner unterstützte mit MALDI-Analyse, bioanalytische Verfahren, Herstellung der caseum Surrogat, chemische Synthese und Isolierung von Kaninchen-caseum. Diese Arbeit wurde mit Mitteln der Bill und Melinda Gates-Stiftung, Auszeichnung # OPP1044966 und OPP1024050 V. Dartois, NIH Geteilt Instrumentation Grant-S10OD018072 sowie eine gemeinsame Finanzierung von der Bill and Melinda Gates Foundation und Wellcome Trust für ein Kompetenzzentrum durchgeführt für Lead-Optimierung für Krankheiten der Dritten Welt zu P. Wyatt.

Alle Tierversuche wurden in Übereinstimmung mit dem Leitfaden für die Pflege und Verwendung von Labortieren der National Institutes of Health mit Zustimmung des Institutional Animal Care und Use Committee des NIAID (NIH), Bethesda, MD durchgeführt. Alle Studien mit M. tuberculosis wurden in einem Labor mit Biosicherheitsstufe 3 (BSL-3) durchgeführt. 1. Kaninchen Infektionsmodell und Caseum Sammlung <ol><li> Infect Neuseeland weiße Kaninchen mit M. tuberculosis einen nasen nur Aerosol - Belichtungssystem unter Verwendung von wie oben beschrieben. 12, 13 erlauben die Infektion für 12-16 Wochen fortzuschreiten. Sedate die Kaninchen, die mit 35 mg / kg Ketamin und 5 mg / kg Xylazin intramuskulär, euthanize die Kaninchen mit 0,22 ml / kg Pentobarbital-Natrium und Phenytoin-Natrium intravenös und mit den necropsies fortzufahren. </li><li> Mit einer Pinzette und Skalpell entfernen Lunge aus der Brust cavity. Von jedem Lungenlappen, seziert aus einzelnen Hohlräumen und großen nekrotischen Granulome mit einem Skalpell. Vorsichtig abkratzen caseum aus dem Hohlraum und Granulom Wänden. Wiegen, aufnehmen und speichern Proben in 2 ml Röhrchen mit Schraubverschluss bei -20 ° C bis zur Verwendung. </li><li> Gamma-Bestrahlung der infektiösen caseum Proben bei 3 MegaRad auf Trockeneis sie uninfectious und sicher für den Einsatz in einem BSL-2 Labor zu machen. </li></ol> 2. In - vitro - Erzeugung von Caseum Surrogate von THP-1 - Zellen <ol><li> Wachsen THP-1 Monozyten in RPMI 1640-Medium (2 mM L-Glutamin und 10% fötales Rinderserum) in T175 Zellkulturflaschen (80 ml / Kolbe). Inkubieren der Kolben in einer 5% CO 2 -Atmosphäre bei 37 ° C für 3-4 Tage. </li><li> Zentrifugieren der Kultur aus einer T175-Kolben in zwei 50 ml konischen Röhrchen bei 150 × g für 5 min. Überstand verwerfen und suspendiert das Pellet in 10 ml RPMI 1640 Medien. </li><li> Pipette 5 &amp; mgr; l dieser Kultur in ein 1,5 ml-Röhrchen mit 45 &amp; mgr; l tRypan blau. Gründlich mischen durch Pipettieren. Übertragung 10 &amp; mgr; l zu einem Hämozytometer und zählen die Anzahl der lebensfähigen THP-1-Monozyten (ungefärbten) ein Lichtmikroskop (Vergrßerung 10X) verwendet wird. Berechnen Sie die Anzahl der lebenden Zellen pro ml der Kultur. Verdünne mit RPMI - Medium auf die Enddichte von 1,25 x 10 6 Zellen / ml. </li><li> Last 40 ml der Kultur auf einer großen Zellkulturplatte (50 x 10 6 Zellen / Platte). Werden 40 &amp; mgr; l von 100 &amp; mgr; M PMA (Phorbol-12-Azetat-myristate13 in Ethanol hergestellt) und lassen Zellen über Nacht in dem Inkubator haften. HINWEIS: Endgültige Konzentration von PMA ist 100 nM. </li><li> Verdünnte reine Ölsäure (OA) (0,89 g / ml) in Ethanol zu einer Konzentration von 0,1 M (dh 31,7 uL OA in 968,3 &amp; mgr; l Ethanol). Man verdünnt diese Lösung in frischem vorgewärmtem RPMI Medium auf eine Konzentration von 10 mM. Man verdünnt diesen OA Suspension auf 0,4 mM (endgültige Arbeitskonzentration) in RPMI-Medium vorgewärmt auf 37 ° C. </li><li> Entfernen Sie die vorhandenen Medien und nichtAdhärierten Zellen aus den Zellkulturplatten und fügen sanft 40 ml 0,4 mM OA zu den THP-1-Makrophagen (THP-M) hinzu. Inkubieren bei 37 ° C im Inkubator über Nacht. </li><li> Verwenden Sie ein Lichtmikroskop bei 40-facher Vergrößerung, um das Vorhandensein zahlreicher Lipidkörper-Einschlüsse in jedem THP-M visuell zu bestätigen. Entfernen Sie alle RPMI-Medium aus den Zellkulturplatten und waschen Sie die adhärenten Zellen zweimal mit phosphatgepufferter Kochsalzlösung (PBS) unter Verwendung einer 50 ml serologischen Pipette. HINWEIS: Lipidkörper erscheinen als kleine, klare, sphärische Strukturen im Cytoplasma des THP-M. </li><li> Füge 40 ml 5 mM Ethylendiamintetraessigsäure (EDTA) in PBS zu jeder Platte hinzu. 15 min bei 37 ° C inkubieren. </li><li> Lösen Sie die schaumigen Makrophagen (FM) durch wiederholtes Pipettieren über die Oberfläche der ganzen Platte mit einer 10-mL serologischen Pipette. Übertragen Sie die Zellsuspension auf ein 50-ml-Kegelrohr und drehen Sie sie bei 150 xg für 5 min. </li><li> Das Zellpellet wird in 10 ml PBS (dritter PBS-Wäsche) a resuspendiertNd Übertragung auf eine vorgewogene 15-ml-konische Rohre. Spinne bei 150 xg für 5 min. Den Überstand sorgfältig mit einer serologischen Pipette abspülen und entsorgen. </li><li> Betrachten Sie die FM-Pellets zu 3 Gefrier-Tau-Zyklen, um die Zellen zu lysieren und sie bei 75 ° C für 20-30 min zu inkubieren, um Proteine ​​in der Matrix zu denaturieren. Die Pellets bei -20 ° C bis zum Gebrauch aufbewahren. </li></ol> 3. Rapid Equilibrierung Dialyse (RED) Assay <ol><li> 10 mM Stammlösungen aller Testverbindungen in Dimethylsulfoxid (DMSO) vorbereiten. Verdünnen Sie zu 500 μM Arbeitslösungen in DMSO vor jedem Assay. </li><li> Wiegen Sie die Röhre mit dem Fallum Surrogat Pellet. Subtrahiere das Gewicht des leeren Rohres, um das Gewicht des Pellets allein abzuleiten. Füge 2-3 Metallperlen pro Röhrchen hinzu und unter Verwendung eines Gewebehomogenisators bei 1.200 Hüben / min für 1 min den Fallum oder die Surrogatmatrix in PBS (1: 9 w / v) zu stören, um 10x verdünnte Suspension jeder Matrix zu erreichen. </li><li> Spike 6,5 μl der 500ΜM-Lösung der Testverbindung in 643,5 &amp; mgr; l des Homogenats, um die Endkonzentration von 5 &amp; mgr; M (&amp; le; 1% DMSO) zu erreichen und zu verwirbeln. </li><li> Legen Sie die ROT-Einsätze in die Grundplatte. Füge 200 μl der drogenspiked Matrix in die Spenderkammer (roter Ring) jedes RED-Inserts und 350 μl PBS in jede Empfängerkammer ein. Vorbereiten von 3 Einsätzen für jede Testverbindung (dreifache Proben). Siegelplatte mit einer Klebeplatte abdichten und bei 37 ° C auf dem Thermomixer bei 200 U / min (1 xg) für 4 h inkubieren. </li><li> Nach der Inkubation mischen Sie den Inhalt der Spender- und Empfängerkammern vorsichtig 2-3 mal auf und ab. 20 μl Aliquote von Homogenat aus den Spenderkammern pipettieren und 20 μl sauberes PBS in ein 1,5 mL Röhrchen (1: 1) zugeben. In ähnlicher Weise pipettieren Sie 20 μl Aliquots von PBS-Proben aus den Empfängerkammern und fügen Sie 20 μl sauberes Homogenat (Matrix-Matching) hinzu. 8 HINWEIS: Matrix-Matching eliminiert die neFür 2 separate Kalibrierkurven (in Homogenat und PBS) für die quantitative Analyse. Der Inhalt der Spenderkammer kann im Laufe der Zeit sedimentieren. Den Inhalt vor dem Entfernen von Aliquoten vorsichtig mischen. </li></ol> 4. LC-MS Quantifizierung und Datenanalyse <ol><li> Fügen Sie 160 μl 1: 1 Methanol: Acetonitril mit 500 ng / ml Diclofenac oder 10 ng / ml Verapamil (interner Standard) zu jedem Röhrchen hinzu und verwirbeln Sie, um Proteine ​​auszufällen. Zentrifugieren bei 10.000 xg für 5 min, um den Niederschlag zu sedimentieren und die Überstände in 96-Well-Tiefbrunnen-Platten zur Flüssigchromatographie-Massenspektrometrie (LCMS) zu überführen. 7 </li><li> Erstellen Sie Kalibrierkurven von 1-1.000 nM für jede Testverbindung, während Sie die gleiche Matrixzusammensetzung wie die obigen Proben halten. Quantifizieren Sie die Konzentration der Testverbindung in Proben aus den Spender- und Empfängerkammern nach einer LC-MS-Methode. </li><li> Berechnen Sie den ungebundenen Bruch ( f u ) of die Droge in verdünnter Matrix unter Verwendung von Gleichung 1. Berechne des f u in unverdünnter Matrixgleichung unter Verwendung von 2 (D = Verdünnungsfaktor von 10). 14 <img alt="Gleichung 1" src="/files/ftp_upload/55559/55559eq1.jpg" /> <img alt="Gleichung 2" src="/files/ftp_upload/55559/55559eq2.jpg" /></li><li> Überprüfen Sie die Wiederherstellung (Massenbilanz) jeder Verbindung unter Verwendung von Gleichung 3 zu identifizieren Verbindungen mit Stabilität / Stoffwechsel / nicht-spezifische Bindungsprobleme. HINWEIS: Wiederherstellung fällt typischerweise zwischen 70% und 130%. 15 <img alt="Gleichung 3" src="/files/ftp_upload/55559/55559eq3.jpg" /></li></ol>

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Pulmonary nekrotische Läsionen und Hohlräumen bei Tuberkulose-infizierten Patienten enthalten Subpopulationen von Bakterien, die zur medikamentösen Behandlung recalcitrant sind. Die käsigen Kerne dieser Strukturen sind besonders verantwortlich, diese persisters in einer extrazellulären Umgebung für die Beherbergung. 16 günstige Verteilung von antibakteriellen Mitteln in diese entfernten Standorte wird angenommen , dass eine wichtige Determinante der Tuberkulose Wirksamkeit von Medikamenten...

Die Behandlung der pulmonalen Tuberkulose-Krankheit erfordert eine effektive Verteilung der Medikamente in verschiedene Arten von Läsionen. Nekrotische Läsionen und Hohlräume enthalten käsige Zentren, die Subpopulationen von drogenverträglichen oder &quot;persistenten&quot; Bakterien beherbergen. 1 , 2 Die Kavitationserkrankung ist mit minderwertigen Heilungsraten und schlechter Prognose verbunden. 3 , 4 Frühere Studien haben gezeigt, dass mit Hilfe von quantitativen und bildgebenden Techniken die Fähigkeit, in den Fall zu dringen, signifikant von einer Medikamentenklasse zur anderen variiert. 5 , 6 Diese Methoden erfordern jedoch die Verwendung von Tierinfektionsmodellen, die langsam und langwierig sind. Ein in vitro- Assay, der die Arzneimittelbindung an ex vivo caseum misst, wurde entworfen. Diese Bindung wurde gefunden, um umgekehrt mit der Arzneimittelpenetration in käsigen Granulomen zu korrelieren und ist daherAls prädiktives Werkzeug verwendet. 7 Gleichgewichtsdialyse gilt als der Goldstandardansatz für Plasmaprotein-Bindungsstudien. Die RED-Vorrichtung (Rapid Equilibrium Dialyse) bietet ein schnelles, einfach zu bedienendes und zuverlässiges System zur Durchführung solcher Assays. 8 Das Gerät besteht aus zwei Komponenten: Einweg-Einweg-Einsätze bestehend aus 2 Kammern, die durch einen vertikalen Zylinder mit halbdurchlässiger Membran getrennt sind; Und wiederverwendbare Basisplatten, die bis zu 48 Einsätze zu einem Zeitpunkt aufnehmen können. Die Dialysemembran hat einen 8 kDa-Molekulargewichts-Cutoff (MWCO), der sich ideal für Arzneimittel-Makromolekül-Bindungsstudien eignet. Das hohe Flächen-zu-Volumen-Verhältnis des Membranabteils ermöglicht eine schnelle Dialyse und Äquilibrierung. Sowohl die Einsätze als auch die Basisplatte wurden für eine minimale unspezifische Bindung validiert. Die Kombination der RED-Vorrichtung mit bioanalytischen Techniken liefert genaue Schätzungen der ungebundenen Fraktionen von Arzneimitteln in pLASMA. 8, 9 Obwohl ursprünglich Plasmaproteinbindung zu messen, das RED-Gerät wird in mehreren Gewebebindungsstudien verwendet worden, unter Verwendung von Homogenaten. 10, 11 in diesem Protokoll messen wir Medikament caseum Bindung, die nekrotische Ablagerungen von den nekrotischen Läsionen und der Hohlräume tuberculosis infizierten Kaninchen ausgeschnitten. Die azelluläre und nicht-vaskuläre Natur des käsigen Materials macht es leicht in eine homogene Suspension zu homogenisieren, die mit dem Assay kompatibel ist. Da caseum ist mühsam herzustellen und schwer zu bekommen, wird das Protokoll auch für die Verwendung mit einer Surrogat-Matrix validiert, die von schaumigen Makrophagen hergestellt wird. THP-1 Monozyten abgeleiteten Makrophagen werden mit Ölsäure induziert, um mehrere Lipidkörper ansammeln, die sie geben ihre ‚schäumenden‘ Aussehen. Diese Lipid-beladenen Zellen werden geerntet undverarbeitet, um eine Matrix zu erzeugen, die wir als Ersatz verwenden, um caseum. Diese Studie hat gezeigt , dass die Drogen Bindung an diese Surrogat Matrix korreliert gut mit zu caseum Bindung, effektiv den in vivo nachahmt Prozess, die Arzneimittelpenetration in dem käsigen Kern von Granulomen und Hohlräumen verhindert.

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		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">New Zealand White Rabbits</td>
			<td style="width:203px;">Covance</td>
			<td style="width:147px;">-</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">HN878 Mycobacterium tuberculosis</td>
			<td style="width:203px;">BEI Resources</td>
			<td style="width:147px;">NR-13647&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Ketathesia (Ketamine) 100mg/mL C3N</td>
			<td style="width:203px;">Henry Schein Animal Health</td>
			<td style="width:147px;">56344</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Anased (Xylazine) 100mg/mL</td>
			<td style="width:203px;">Henry Schein Animal Health</td>
			<td style="width:147px;">33198</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Euthasol (pentobarbital sodium and phenytoin sodium) Solution&#160;</td>
			<td style="width:203px;">Virbac</td>
			<td style="width:147px;">710101</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">THP-1 monocytic cell line</td>
			<td style="width:203px;">ATCC</td>
			<td style="width:147px;">ATCC TIB-202</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">175cm&#178; TC-Treated Flask (T175)</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>T-3400-175</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">RPMI 1640 media w/o glutamine</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>MT-15-040-CV</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hyclone Fetal Bovine Serum, Gamma irradiated&#160;</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>SH3091003IR</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hyclone L-glutamine, 200mM</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>SH3003401</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Cellstar TC dish, 145x20mm, vented</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>T-2881-1</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Phorbol 12-myristate13-acetate (PMA)&#160;</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>BP685-1</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ethylenediaminetetraacetic acid</td>
			<td style="width:203px;">Sigma</td>
			<td>E6758</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Oleic acid&#160;</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>ICN15178101</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Pierce RED Device Reusable Base Plate</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>PI-89811</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Pierce RED Device Inserts, 50/box&#160;</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>PI-89809</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Pierce RED insert removal tool&#160;</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>89812</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Adhesive plate seal</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>08-408-240</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PBS, pH7.4, 10 X 500 mL (Gibco)&#160;</td>
			<td style="width:203px;">Life Technologies&#160;</td>
			<td>10010-049</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">DMSO</td>
			<td style="width:203px;">Sigma</td>
			<td>472301</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Acetonitrile</td>
			<td style="width:203px;">Sigma</td>
			<td>34998</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Methanol</td>
			<td style="width:203px;">Sigma</td>
			<td>34860</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Verapamil hydrochloride</td>
			<td style="width:203px;">Sigma</td>
			<td>V4629</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Diclofenac sodium salt</td>
			<td style="width:203px;">Sigma</td>
			<td>93484</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Trypan Blue Solution, 0.4%</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>15-250-061</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Ethanol, 200 proof</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>04-355-451</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">2010 Geno/Grinder</td>
			<td style="width:203px;">SPEX SamplePrep</td>
			<td style="width:147px;">2010</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Bead Mill Homogenizer Accessory, Metal Bulk Beads</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td>15-340-158</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">484R Cobalt 60 Irradiator</td>
			<td style="width:203px;">JL Shepard</td>
			<td style="width:147px;">7810-484-1</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">INCYTO&#160;C-Chip Disposable Hemacytometers</td>
			<td style="width:203px;">Fisher Scientific</td>
			<td style="width:147px;">22-600-100</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Upright Light Microscope</td>
			<td style="width:203px;">Leica</td>
			<td style="width:147px;">DM1000</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Binary Liquid Chromatography system</td>
			<td style="width:203px;">Agilent</td>
			<td style="width:147px;">1260</td>
			<td>Multi-compenent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:443px;">Mass spectrometer</td>
			<td style="width:203px;">AB Sciex</td>
			<td>4000</td>
			<td></td>
		</tr>
	</tbody>
</table>

an in vitro caseum binding assay that predicts drug penetration in tuberculosis lesions

Die Tilgung der Tuberkulose-Krankheit erfordert Medikamentenregimen, die die Mehrfachschichten komplexer Lungenläsionen durchdringen können. Die Arzneimittelverteilung in den käsigen Adern von Hohlräumen und Läsionen ist besonders wichtig, weil sie Subpopulationen von drogenverträglichen Bakterien, die auch allgemein als persisten bezeichnet werden, beherbergen. Bestehende Methoden zur Messung der Arzneimittelpenetration bei Tuberkulose-Läsionen beinhalten kostspielige und zeitaufwändige in vivo- pharmakokinetische Studien, gekoppelt an bioanalytische oder bildgebende Verfahren. Die In-vitro- Messung der Arzneimittelbindung an Fallmakromoleküle wurde als Alternative zu solchen Techniken vorgeschlagen, da diese Bindung die passive Diffusion von Arzneimittelmolekülen durch den Fall beeinträchtigt. Die schnelle Gleichgewichtsdialyse ist ein schnelles und zuverlässiges System zur Durchführung von Plasmaprotein- und Gewebebindungsstudien. In diesem Protokoll haben wir eine schnelle Gleichgewichts-Dialyse (RED) -Gerät verwendet, um die Arzneimittelbindung an Homogenate von caseum zu untersuchen, das excis istAus den Läsionen und Hohlräumen von Tuberkulose-infizierten Kaninchen. Das Protokoll beschreibt auch, wie man eine Surrogatmatrix aus lipidbeladenen THP-1-Makrophagen erzeugt, um anstelle von caseum zu verwenden. Dieser Fall / Surrogat-Bindungstest ist ein wichtiges Instrument in der Tuberkulose-Wirkstoffforschung und kann angepasst werden, um die Arzneimittelverteilung bei Läsionen oder Abszessen, die durch andere Krankheiten verursacht werden, zu untersuchen.

Mit diesem Protokoll haben wir Hunderte von Tuberkulose Medikament Entwicklung Verbindungen für ihre vorhergesagte Effizienz bei Eindringen Fallum getestet. Abbildung 1 zeigt die Grundkonzepte des ROTEN Assays. Die Dialysemembran der RED-Inserts ermöglicht es, dass ungebundene kleine Moleküle vom Spenderbrunnen zum Empfänger gut diffundieren und schließlich ein Gleichgewicht zwischen beiden Kompartimenten erreichen. Kleine Moleküle, die an Makromoleküle wie Protei...

Watch this Scientific Journal Video about An In Vitro Caseum Binding Assay that Predicts Drug Penetration in Tuberculosis Lesions at JoVE.com

An In Vitro Caseum Binding Assay that Predicts Drug Penetration in Tuberculosis Lesions

Hier beschreiben wir eine schnelle Gleichgewichtsdialyse (RED) Methode zur Messung der Arzneimittelbindung an den Fall aus pulmonalen Tuberkuloseläsionen und Hohlräumen. Das Protokoll wird auch mit einer schaumigen Makrophagen-abgeleiteten Matrix verwendet, die ein wirksames Surrogat zum Fall ist.

Ein<em&gt; In Vitro</em&gt; Caseum-Bindungsassay, der die Drug Penetration in Tuberkulose-Läsionen vorhersagt

The eradication of tuberculosis disease requires drug regimens that can penetrate the multiple layers of complex pulmonary lesions. Drug distribution in ...

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Pharmacokinetics and Pharmacodynamics

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Immunology and Infection

Unit 1

An In Vitro Caseum Binding Assay that Predicts Drug Penetration in Tuberculosis Lesions

Nonlinear Pharmacokinetics

Introduction to Respiratory System Drugs

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11.6K Aufrufe.  Rutgers.  Hier beschreiben wir eine schnelle Gleichgewichtsdialyse (RED) Methode zur Messung der Arzneimittelbindung an den Fall aus pulmonalen Tuberkuloseläsionen und Hohlräumen. Das Protokoll wird auch mit einer schaumigen Makrophagen-abgeleiteten Matrix verwendet, die ein wirksames Surrogat zum Fall ist. 

Serie: An In Vitro Caseum Binding Assay that Predicts Drug Penetration in Tuberculosis Lesions

In vitro Biofilm Formation in an 8-well Chamber Slide

The chronic nature of many diseases is attributed to the formation of bacterial biofilms which are recalcitrant to traditional antibiotic therapy. Biofilms are community-associated bacteria attached to a surface and encased in a matrix. The role of the extracellular matrix is multifaceted, including facilitating nutrient acquisition, and offers significant protection against environmental stresses (e.g. host immune responses). In an effort to acquire a better understanding as to how the bacteria within a biofilm respond to environmental stresses we have used a protocol wherein we visualize bacterial biofilms which have formed in an 8-well chamber slide. The biofilms were stained with the BacLight Live/Dead stain and examined using a confocal microscope to characterize the relative biofilm size, and structure under varying incubation conditions. Z-stack images were collected via confocal microscopy and analyzed by COMSTAT. This protocol can be used to help elucidate the mechanism and kinetics by which biofilms form, as well as identify components that are important to biofilm structure and stability.

In vitro Biofilm Formation in an 8-well Chamber Slide

This article describes the procedure for the formation and visualization of a bacterial biofilm grown within an 8-well chamber slide

In-vitro-Bildung von Biofilmen in einem 8-well Chamber Slide

The chronic nature of many diseases is attributed to the formation of bacterial biofilms which are recalcitrant to traditional antibiotic therapy. ...

Forschung

Immunologie und Infektion

Facilitating Drug Discovery: An Automated High-content Inflammation Assay in Zebrafish

Zebrafish larvae are particularly amenable to whole animal small molecule screens1,2 due to their small size and relative ease of manipulation and observation, as well as the fact that compounds can simply be added to the bathing water and are readily absorbed when administered in a &lt;1% DMSO solution. Due to the optical clarity of zebrafish larvae and the availability of transgenic lines expressing fluorescent proteins in leukocytes, zebrafish offer the unique advantage of monitoring an acute inflammatory response in vivo. Consequently, utilizing the zebrafish for high-content small molecule screens aiming at the identification of immune-modulatory compounds with high throughput has been proposed3-6, suggesting inflammation induction scenarios e.g. localized nicks in fin tissue, laser damage directed to the yolk surface of embryos7 or tailfin amputation3,5,6. The major drawback of these methods however was the requirement of manual larva manipulation to induce wounding, thus preventing high-throughput screening. Introduction of the chemically induced inflammation (ChIn) assay8 eliminated these obstacles. Since wounding is inflicted chemically the number of embryos that can be treated simultaneously is virtually unlimited. Temporary treatment of zebrafish larvae with copper sulfate selectively induces cell death in hair cells of the lateral line system and results in rapid granulocyte recruitment to injured neuromasts. The inflammatory response can be followed in real-time by using compound transgenic cldnB::GFP/lysC::DsRED26,9 zebrafish larvae that express a green fluorescent protein in neuromast cells, as well as a red fluorescent protein labeling granulocytes.
In order to devise a screening strategy that would allow both high-content and high-throughput analyses we introduced robotic liquid handling and combined automated microscopy with a custom developed software script. This script enables automated quantification of the inflammatory response by scoring the percent area occupied by red fluorescent leukocytes within an empirically defined area surrounding injured green fluorescent neuromasts. Furthermore, we automated data processing, handling, visualization, and storage all based on custom developed MATLAB and Python scripts.
In brief, we introduce an automated HC/HT screen that allows testing of chemical compounds for their effect on initiation, progression or resolution of a granulocytic inflammatory response. This protocol serves a good starting point for more in-depth analyses of drug mechanisms and pathways involved in the orchestration of an innate immune response. In the future, it may help identifying intolerable toxic or off-target effects at earlier phases of drug discovery and thereby reduce procedural risks and costs for drug development.

Here we describe a novel high-content chemically induced inflammation assay aiming at the identification of immune-modulatory bioactives. We have successfully combined automated microscopy with custom developed software scripts enabling automated quantification of the inflammatory response as well as further data processing, analysis, mining, and storage.

Die Erleichterung Drug Discovery: Eine automatisierte High-Content-Assay Entzündung im Zebrafisch

Zebrafish larvae are particularly amenable to whole animal small molecule screens1,2 due to their small size and relative ease of manipulation and ...

Quantitative In vitro Assay to Measure Neutrophil Adhesion to Activated Primary Human Microvascular Endothelial Cells under Static Conditions

The vascular endothelium plays an integral part in the inflammatory response. During the acute phase of inflammation, endothelial cells (ECs) are activated by host mediators or directly by conserved microbial components or host-derived danger molecules. Activated ECs express cytokines, chemokines and adhesion molecules that mobilize, activate and retain leukocytes at the site of infection or injury. Neutrophils are the first leukocytes to arrive, and adhere to the endothelium through a variety of adhesion molecules present on the surfaces of both cells. The main functions of neutrophils are to directly eliminate microbial threats, promote the recruitment of other leukocytes through the release of additional factors, and initiate wound repair. Therefore, their recruitment and attachment to the endothelium is a critical step in the initiation of the inflammatory response. In this report, we describe an in vitro neutrophil adhesion assay using calcein AM-labeled primary human neutrophils to quantitate the extent of microvascular endothelial cell activation under static conditions. This method has the additional advantage that the same samples quantitated by fluorescence spectrophotometry can also be visualized directly using fluorescence microscopy for a more qualitative assessment of neutrophil binding.

Quantitative In vitro Assay to Measure Neutrophil Adhesion to Activated Primary Human Microvascular Endothelial Cells under Static Conditions

Neutrophil adherence to the activated endothelium at sites of infection is an integral component of the host's inflammatory response. Described in this report is a neutrophil binding assay that allows for the in vitro quantitation of primary human neutrophil binding to endothelial cells activated by inflammatory mediators under static conditions.

Quantitative<em&gt; In-vitro-</em&gt; Assay auf Neutrophile Haftung auf Aktiviert primären humanen mikrovaskulären Endothelzellen unter statischen Bedingungen messen

The vascular  endothelium plays an integral part in the inflammatory response. During the  acute phase of inflammation, endothelial cells (ECs) are ...

An Experimental Model to Study Tuberculosis-Malaria Coinfection upon Natural Transmission of Mycobacterium tuberculosis and Plasmodium berghei

Coinfections naturally occur due to the geographic overlap of distinct types of pathogenic organisms. Concurrent infections most likely modulate the respective immune response to each single pathogen and may thereby affect pathogenesis and disease outcome. Coinfected patients may also respond differentially to anti-infective interventions. Coinfection between tuberculosis as caused by mycobacteria and the malaria parasite Plasmodium, both of which are coendemic in many parts of sub-Saharan Africa, has not been studied in detail. In order to approach the challenging but scientifically and clinically highly relevant question how malaria-tuberculosis coinfection modulate host immunity and the course of each disease, we established an experimental mouse model that allows us to dissect the elicited immune responses to both pathogens in the coinfected host. Of note, in order to most precisely mimic naturally acquired human infections, we perform experimental infections of mice with both pathogens by their natural routes of infection, i.e. aerosol and mosquito bite, respectively.

An Experimental Model to Study Tuberculosis-Malaria Coinfection upon Natural Transmission of Mycobacterium tuberculosis and Plasmodium berghei

Tuberculosis and malaria are two of the most prevalent infections in humans and major causes of morbidity and mortality in impoverished populations in the tropics. We established an experimental model system to study outcome of malaria-tuberculosis coinfection in mice after challenge with both pathogens via their natural route of infection.

Eine experimentelle Modell zum Studium Tuberkulose-Koinfektion auf Natur Malaria Übertragung von Mycobacterium tuberculosis Und Plasmodium berghei</i

Coinfections naturally occur due to the geographic overlap of distinct types of pathogenic organisms. Concurrent infections most likely modulate the ...

Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay

Adherence of Streptococcus pneumoniae (the pneumococcus) to the epithelial lining of the nasopharynx can result in colonization and is considered a prerequisite for pneumococcal infections such as pneumonia and otitis media. In vitro adherence assays can be used to study the attachment of pneumococci to epithelial cell monolayers and to investigate potential interventions, such as the use of probiotics, to inhibit pneumococcal&#160;colonization.&#160;The protocol described here is used to investigate the effects of the probiotic Streptococcus salivarius on the adherence of pneumococci to the human epithelial cell line CCL-23 (sometimes referred to as HEp-2 cells). The assay involves three main steps: 1) preparation of epithelial and bacterial cells, 2) addition of bacteria to epithelial cell monolayers, and 3) detection of adherent pneumococci by viable counts (serial dilution and plating) or quantitative real-time PCR (qPCR). This technique is relatively straightforward and does not require specialized equipment other than a tissue culture setup. The assay can be used to test other probiotic species and/or potential inhibitors of pneumococcal colonization and can be easily modified to address other scientific questions regarding pneumococcal adherence and invasion.

Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay

In vitro adherence assays can be used to study the attachment of Streptococcus pneumoniae to epithelial cell monolayers and to investigate potential interventions such as the use of probiotics for inhibiting pneumococcal colonization.

Untersuchung der Effekte von Probiotika auf Pneumokokken-Kolonisation Mit ein<em&gt; In-vitro-</em&gt; Einhaltung Assay

Adherence of Streptococcus pneumoniae (the pneumococcus) to the epithelial lining of the nasopharynx can result in colonization and is considered a ...

Demonstrating a Multi-drug Resistant Mycobacterium tuberculosis Amplification Microarray

Simplifying microarray workflow is a necessary first step for creating MDR-TB microarray-based diagnostics that can be routinely used in lower-resource environments. An amplification microarray combines asymmetric PCR amplification, target size selection, target labeling, and microarray hybridization within a single solution and into a single microfluidic chamber. A batch processing method is demonstrated with a 9-plex asymmetric master mix and low-density gel element microarray for genotyping multi-drug resistant Mycobacterium tuberculosis (MDR-TB). The protocol described here can be completed in 6 hr and provide correct genotyping with at least 1,000 cell equivalents of genomic DNA. Incorporating on-chip wash steps is feasible, which will result in an entirely closed amplicon method and system. The extent of multiplexing with an amplification microarray is ultimately constrained by the number of primer pairs that can be combined into a single master mix and still achieve desired sensitivity and specificity performance metrics, rather than the number of probes that are immobilized on the array. Likewise, the total analysis time can be shortened or lengthened depending on the specific intended use, research question, and desired limits of detection. Nevertheless, the general approach significantly streamlines microarray workflow for the end user by reducing the number of manually intensive and time-consuming processing steps, and provides a simplified biochemical and microfluidic path for translating microarray-based diagnostics into routine clinical practice.

Demonstrating a Multi-drug Resistant Mycobacterium tuberculosis Amplification Microarray

An amplification microarray combines asymmetric PCR amplification and microarray hybridization into a single chamber, which significantly streamlines microarray workflow for the end user. Simplifying microarray workflow is a necessary first step for creating microarray-based diagnostics that can be routinely used in lower-resource environments.

Der Nachweis eines multiresistenten<em&gt; Mycobacterium tuberculosis</em&gt; Verstärkung Microarray

Simplifying microarray workflow is a necessary first step for creating MDR-TB microarray-based diagnostics that can be routinely used in lower-resource ...

A Reference Broth Microdilution Method for Dalbavancin In Vitro Susceptibility Testing of Bacteria that Grow Aerobically

Antimicrobial susceptibility testing (AST) is performed to assess the in vitro activity of antimicrobial agents against various bacteria. The AST results, which are expressed as minimum inhibitory concentrations (MICs) are used in research for antimicrobial development and monitoring of resistance development and in the clinical setting for antimicrobial therapy guidance. Dalbavancin is a semi-synthetic lipoglycopeptide antimicrobial agent that was approved in May 2014 by the Food and Drug Administration (FDA) for the treatment of acute bacterial skin and skin structure infections caused by Gram-positive organisms. The advantage of dalbavancin over current anti-staphylococcal therapies is its long half-life, which allows for once-weekly dosing. Dalbavancin has activity against Staphylococcus aureus (including both methicillin-susceptible S. aureus [MSSA] and methicillin-resistant S. aureus [MRSA]), coagulase-negative staphylococci, Streptococcus pneumoniae, Streptococcus anginosus group, &#946;-hemolytic streptococci and vancomycin susceptible enterococci. Similar to other recent lipoglycopeptide agents, optimization of CLSI and ISO broth susceptibility test methods includes the use of dimethyl sulfoxide (DMSO) as a solvent when preparing stock solutions and polysorbate 80 (P80) to alleviate adherence of the agent to plastic. Prior to the clinical studies and during the initial development of dalbavancin, susceptibility studies were not performed with the use of P-80 and MIC results tended to be 2-4 fold higher and similarly higher MIC results were obtained with the agar dilution susceptibility method. Dalbavancin was first included in CLSI broth microdilution methodology tables in 2005 and amended in 2006 to clarify use of DMSO and P-80. The broth microdilution (BMD) procedure shown here is specific to dalbavancin and is in accordance with the CLSI and ISO methods, with step-by-step detail and focus on the critical steps added for clarity.

A Reference Broth Microdilution Method for Dalbavancin In Vitro Susceptibility Testing of Bacteria that Grow Aerobically

Here, we present a protocol for determination of dalbavancin susceptibility of clinically relevant Gram-positive bacteria using a broth microdilution reference methodology.

Eine Referenz Broth Mikrodilutionsverfahren für Dalbavancin<em&gt; In-vitro-</em&gt; Empfindlichkeitsprüfung von Bakterien, die wachsen aerob

Antimicrobial susceptibility testing (AST) is performed to assess the in vitro activity of antimicrobial agents against various bacteria. The AST results, ...

Establishment of a High-throughput Setup for Screening Small Molecules That Modulate c-di-GMP Signaling in Pseudomonas aeruginosa

Bacterial resistance to traditional antibiotics has driven research attempts to identify new drug targets in recently discovered regulatory pathways. Regulatory systems that utilize intracellular cyclic di-GMP (c-di-GMP) as a second messenger are one such class of target. c-di-GMP is a signaling molecule found in almost all bacteria that acts to regulate an extensive range of processes including antibiotic resistance, biofilm formation and virulence. The understanding of how c-di-GMP signaling controls aspects of antibiotic resistant biofilm development has suggested approaches whereby alteration of the cellular concentrations of the nucleotide or disruption of these signaling pathways may lead to reduced biofilm formation or increased susceptibility of the biofilms to antibiotics. We describe a simple high-throughput bioreporter protocol, based on green fluorescent protein (GFP), whose expression is under the control of the c-di-GMP responsive promoter cdrA, to rapidly screen for small molecules with the potential to modulate c-di-GMP cellular levels in Pseudomonas aeruginosa (P. aeruginosa). This simple protocol can screen upwards of 3,500 compounds within 48 hours and has the ability to be adapted to multiple microorganisms.

Establishment of a High-throughput Setup for Screening Small Molecules That Modulate c-di-GMP Signaling in Pseudomonas aeruginosa

This article describes the high-throughput assay that has been successfully established to screen large libraries of small molecules for their potential ability to manipulate cellular levels of cyclic di-GMP in Pseudomonas aeruginosa, providing a new powerful tool for antibacterial drug discovery and compound testing.

Einrichtung eines Setup-Hochdurchsatz-Screening für kleine Moleküle, die Modulate c-di-GMP-Signalisierung in<em&gt; Pseudomonas aeruginosa</em

Bacterial resistance to traditional antibiotics has driven research attempts to identify new drug targets in recently discovered regulatory pathways. ...

A High-throughput Compatible Assay to Evaluate Drug Efficacy against Macrophage Passaged Mycobacterium tuberculosis

The early drug development process for anti-tuberculosis drugs is hindered by the inefficient translation of compounds with in vitro activity to effectiveness in the clinical setting. This is likely due to a lack of consideration for the physiologically relevant cellular penetration barriers that exist in the infected host. We recently established an alternative infection model that generates large macrophage aggregate structures containing densely packed M. tuberculosis (Mtb) at its core, which was suitable for drug susceptibility testing. This infection model is inexpensive, rapid, and most importantly BSL-2 compatible. Here, we describe the experimental procedures to generate Mtb/macrophage aggregate structures that would produce macrophage-passaged Mtb for drug susceptibility testing. In particular, we demonstrate how this infection system could be directly adapted to the 96-well plate format showing throughput capability for the screening of compound libraries against Mtb. Overall, this assay is a valuable addition to the currently available Mtb drug discovery toolbox due to its simplicity, cost effectiveness, and scalability.

A High-throughput Compatible Assay to Evaluate Drug Efficacy against Macrophage Passaged Mycobacterium tuberculosis

New models and assays that would improve the early drug development process for next-generation anti-tuberculosis drugs are highly desirable. Here, we describe a quick, inexpensive, and BSL-2 compatible assay to evaluate drug efficacy against Mycobacterium tuberculosis that can be easily adapted for high-throughput screening.

Ein Hochdurchsatz-Assay unterstützte Wirksamkeit von Medikamenten gegen Makrophagen agierten zur Bewertung<em&gt; Mycobacterium tuberculosis</em

The early drug development process for anti-tuberculosis drugs is hindered by the inefficient translation of compounds with in vitro activity to ...

In Vitro Methods for Comparing Target Binding and CDC Induction Between Therapeutic Antibodies: Applications in Biosimilarity Analysis

Therapeutic monoclonal antibodies (mAbs) are relevant to the treatment of different pathologies, including cancers. The development of biosimilar mAbs by pharmaceutical companies is a market opportunity, but it is also a strategy to increase drug accessibility and reduce therapy-associated costs. The protocols detailed here describe the evaluation of target binding and CDC induction by rituximab in Daudi cells. These two functions require different structural regions of the antibody and are relevant to the clinical effect induced by rituximab. The protocols allow the side-to-side comparison of a reference rituximab and a marketed rituximab biosimilar. The evaluated products showed differences both in target binding and CDC induction, suggesting that there are underlying physicochemical differences and highlighting the need to analyze the impact of those differences in the clinical setting. The methods reported here constitute simple and inexpensive in vitro models for the evaluation of the activity of rituximab biosimilars. Thus, they can be useful during biosimilar development, as well as for quality control in biosimilar production. Furthermore, the presented methods can be extrapolated to other therapeutic mAbs.

In Vitro Methods for Comparing Target Binding and CDC Induction Between Therapeutic Antibodies: Applications in Biosimilarity Analysis

This protocol describes the in vitro comparison of two key functional characteristics of rituximab: target binding and complement-dependent cytotoxicity (CDC) induction. The methods were employed for a side-to-side comparison between reference rituximab and a rituximab biosimilar. These assays can be employed during biosimilar development or as a quality control in their production.

In - vitro - Methoden zum Vergleich der Zielbindungs und CDC Induktion zwischen Therapeutische Antikörper: Anwendungen in Biosimilarity Analyse

Therapeutic monoclonal antibodies (mAbs) are relevant to the treatment of different pathologies, including cancers. The development of biosimilar mAbs by ...