Name: customization of aspergillus niger morphology through addition of talc micro particles
Uploaded: 2012-03-15T13:00:00
Duration: 10 min 51 s
Description: Watch this Scientific Journal Video about Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles at JoVE.com

החוקרים בתודה להכיר תמיכה כספית הניתנת על ידי קרן המחקר הגרמנית (DFG) באמצעות מחקר משותף במרכז SFB 578 &quot;מאת ג&#39;ין למוצר&quot; על אוניברסיטת Technische בראונשווייג, גרמניה.

<ol>
	<li>Wucherpfennig, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Advances in Applied Microbiology. 72, 89-136 (2010).</li><li>Driouch, H., H&#228;nsch, R., Wucherpfennig, T., Krull, R., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+enzyme+production+by+bio-pellets+of+Aspergillus+niger:+Targeted+morphology+engineering+using+titanate+microparticles.">Improved enzyme production by bio-pellets of Aspergillus niger: Targeted morphology engineering using titanate microparticles.</a> Biotechnology and Bioengineering. 109, 462-471 (2012).</li><li>Driouch, H., Roth, A., Dersch, P., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimized+bioprocess+for+production+of+fructofuranosidase+by+recombinant+Aspergillus+niger.">Optimized bioprocess for production of fructofuranosidase by recombinant Aspergillus niger.</a> Applied Microbiology and Biotechnology. 87, 2011-2024 (2010).</li><li>Driouch, H., Roth, A., Dersch, P., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Filamentous+fungi+in+good+shape:+Microparticles+for+tailor-made+fungal+morphology+and+enhanced+enzyme+production.">Filamentous fungi in good shape: Microparticles for tailor-made fungal morphology and enhanced enzyme production.</a> Bioengineered Bugs. 2, 100-104 (2011).</li><li>Driouch, H., Sommer, B., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphology+engineering+of+Aspergillus+niger+for+improved+enzyme+production.">Morphology engineering of Aspergillus niger for improved enzyme production.</a> Biotechnology and Bioengineering. 105, 1058-1068 (2010).</li><li>Kaup, B. -. A., Ehrich, K., Pescheck, M., Schrader, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microparticle-enhanced+cultivation+of+filamentous+microorganisms:+Increased+chloroperoxidase+formation+by+Caldariomyces+fumago+as+an+example.">Microparticle-enhanced cultivation of filamentous microorganisms: Increased chloroperoxidase formation by Caldariomyces fumago as an example.</a> Biotechnology and Bioengineering. 99, 491-498 (2008).</li><li>Hirayama, M., Sumi, N., Hidaka, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+and+characterization+of+a+fructooligosaccharide-producing+beta-fructofuranosidase+from+Aspergillus+niger+ATCC+20611.">Purification and characterization of a fructooligosaccharide-producing beta-fructofuranosidase from Aspergillus niger ATCC 20611.</a> Agricultural and Biological Chemistry. 53, 667-673 (2006).</li><li>Rajoka, M. I., Yasmeen, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+productivity+of+beta-fructofuranosidase+by+a+derepressed+mutant+of+Aspergillus+niger+form+conventional+and+non-conventional+substrates.">Improved productivity of beta-fructofuranosidase by a derepressed mutant of Aspergillus niger form conventional and non-conventional substrates.</a> World Journal of Microbiology and Biotechnology. 21, 471-478 (2005).</li><li>Zuccaro, A., G&#195;&#182;tze, S., Kneip, S., Dersch, P., Seibel, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tailor-made+fructooligosaccharides+by+a+combination+of+substrate+and+genetic+engineering.">Tailor-made fructooligosaccharides by a combination of substrate and genetic engineering.</a> ChemBioChem. 9, 143-149 (2008).</li><li>Huggett, A. S. G., Nixon, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+glucose+oxidase,+peroxidase,+and+o-dianisidin+in+determination+of+blood+and+urinary+glucose.">Use of glucose oxidase, peroxidase, and o-dianisidin in determination of blood and urinary glucose.</a> The Lancet. , 270-368 (1957).</li><li>Wucherpfenning, T., Hestler, T., Krull, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphology+engineering+-+Osmolality+and+its+effect+on+Aspergillus+niger+morphology+and+productivity.">Morphology engineering - Osmolality and its effect on Aspergillus niger morphology and productivity.</a> Microb. Cell Fact. 10, (2011).</li><li>Rasband, W. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> ImageJ. , (1997).</li><li>Papagianni, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+the+fractal+nature+of+mycelial+aggregation+in+Aspergillus+niger+submerged+cultures.">Quantification of the fractal nature of mycelial aggregation in Aspergillus niger submerged cultures.</a> Microbial Cell Factories. 5, 5 (2006).</li></ol>

אין לי מה לחשוף.

שינוי של מורפולוגיה פטרייתי כבר עניין בביוטכנולוגיה מאז עשרות שנים. מחקרים שונים ניסו לשנות פרמטרים של התהליך נבחרה כגון ערך ה-pH, כניסת חשמל, טמפרטורה, חומרי מזון בינוני או ריכוז הבידוד 1, אבל סובלים שליטה מדויקת למדי שלם של מורפולוגיה, עלויות האנרגיה הגבוהות, אפקטים עיכוב או חוסר יציבות המוצר, לעומת זאת, תוספת של חלקיקי מיקרו מאפשר הנדסה מדויקת של מורפולוגיה פטרייתי דרך וריאציה מכויל של גודל החלקיקים וריכוז. זה פותח אפשרויות חדשות לשימוש חלקיקי מיקרו לצורך מיטוב לעיצוב תפורים המורפולוגיה לייצור גבוה הייצור הביוטכנולוגי עם א &#39; ניז&#39;ר ​​ו פילמנטיות מיקרואורגניזמים אחרים. ניתוח תמונה דיגיטלית היא שיטה לשחזור קל לאפיין את המורפולוגיה מאקרו פטרייתי. עם זאת, מגוון רחב של פרמטרים המאפיינים, גודל, צורה השטחטר של מבנים מורפולוגיים המתואר בספרות עושה הערכה מהירה של מורפולוגיה פטרייתי מסובך. מספר מורפולוגיה הציג כשילוב של הפרמטרים הרלוונטיים, ימנע חוסר זה והוא יכול לשמש לא רק אפיון מקיף של מבנים מורפולוגיים, אלא גם קשר מתמטי ישיר עם פרודוקטיביות. זה שוב הופך את הערכת היעילות של מורפולוגיה נתון ולכן התאמה אישית של המורפולוגיה של התהליך צריך האפשר. משתמש מספר מורפולוגיה, ניתן להבחין בין גלולה שונים מורפולוגיות גוש 4.5. להמשך פיתוח של מספר מורפולוגיה תמורת מימד פרקטלית נראה מבטיח. מימד פרקטלית נותנת מדידה מורכבות ומסה מילוי המאפיינים של האובייקט 13 והוא predestinated ולכן לאפיון הוליסטי של מורפולוגיה mycelial. CReation המורפולוגיה גבוהה mycelial לייצור, לעומת זאת, עלול לגרום בעיות עם הביצועים תהליך במיוחד לגידול בקנה מידה גדול, כי צורת הגידול mycelial הוכח בעבר להפגין הרבה יותר מרק viscosities תרבות 2. זה מוביל בעיות עם מעבר חום ומסה היווצרות של מים עומדים באזורים שאינם מעורבים, אשר דורשים תשומת חשמל גבוה ולעשות טיפוח יקר יותר להפעיל 1. לכן הקשר בין המורפולוגיה פטריות מרק צמיגות התרבות יש לשקול בעת שינוי המורפולוגיה להיות משולב בדגמים נוספים.

Table of Equipment:
<table border="1">
	<tbody>
		<tr>
			<td>
			Equipment</td>
			<td>
			Company</td>
			<td>
			Catalogue Number/model</td>
		</tr>
		<tr>
			<td>
			autoclave</td>
			<td>
			Systec</td>
			<td>
			V150</td>
		</tr>
		<tr>
			<td>
			B&uuml;chner funnel (plastic)</td>
			<td>
			VWR</td>
			<td>
			-</td>
		</tr>
		<tr>
			<td>
			cellulose filter (for biomass dry weight)</td>
			<td>
			Sartorius Stedim Biotech</td>
			<td>
			Filter Discs Grade 389</td>
		</tr>
		<tr>
			<td>
			cellulose acetate filter (for air filtration at reactor)</td>
			<td>
			Sartorius stedim biotech</td>
			<td>
			Midisart 200 PTFE</td>
		</tr>
		<tr>
			<td>
			cellulose acetate filter (for enzyme activity)</td>
			<td>
			Sartorius Stedim Biotech</td>
			<td>
			Midisart NML</td>
		</tr>
		<tr>
			<td>
			centrifuge</td>
			<td>
			Eppendorf</td>
			<td>
			Centrifuge 5415R</td>
		</tr>
		<tr>
			<td>
			centrifuge</td>
			<td>
			Heraeus</td>
			<td>
			Biofuge fresco</td>
		</tr>
		<tr>
			<td>
			centrifuge</td>
			<td>
			Heraeus sepatech</td>
			<td>
			Varifuge 3.0R</td>
		</tr>
		<tr>
			<td>
			compartment dryer (105 &deg;C)</td>
			<td>
			Heraeus</td>
			<td>
			Kelvitran t</td>
		</tr>
		<tr>
			<td>
			control unit (temperature)</td>
			<td>
			Jumo</td>
			<td>
			Jumo iTron 08</td>
		</tr>
		<tr>
			<td>
			control unit (pH-value)</td>
			<td>
			meredos</td>
			<td>
			pH Control 2</td>
		</tr>
		<tr>
			<td>
			desiccator</td>
			<td>
			Duran</td>
			<td>
			Vacuum stable</td>
		</tr>
		<tr>
			<td>
			Falcon tubes</td>
			<td>
			Omnilab</td>
			<td>
			FALC352070</td>
		</tr>
		<tr>
			<td>
			heating block 40 &deg;C</td>
			<td>
			Biometra</td>
			<td>
			TB1 Thermoblock</td>
		</tr>
		<tr>
			<td>
			heating block 95 &deg;C</td>
			<td>
			HLC</td>
			<td>
			HBT 130</td>
		</tr>
		<tr>
			<td>
			micro plate reader</td>
			<td>
			Tecan</td>
			<td>
			Sunrise-Microplate-Reader</td>
		</tr>
		<tr>
			<td>
			micro scales</td>
			<td>
			Sartorius</td>
			<td>
			CP 225</td>
		</tr>
		<tr>
			<td>
			microscope (digital inverted)</td>
			<td>
			AMG</td>
			<td>
			EVOS xl</td>
		</tr>
		<tr>
			<td>
			micro pipettes and tips (different sizes)</td>
			<td>
			Omnilab</td>
			<td>
			5283303
			5283298 
			5283299 
			5283300</td>
		</tr>
		<tr>
			<td>
			micro titer plate</td>
			<td>
			Nunc</td>
			<td>
			MaxiSorp</td>
		</tr>
		<tr>
			<td>
			multi pipette and tips</td>
			<td>
			Eppendorf/ Omnilab</td>
			<td>
			5283611/ 5283611</td>
		</tr>
		<tr>
			<td>
			pH-electrode</td>
			<td>
			Schott</td>
			<td>
			pH-Meter CG840</td>
		</tr>
		<tr>
			<td>
			reaction tubes</td>
			<td>
			Roth</td>
			<td>
			E518.1</td>
		</tr>
		<tr>
			<td>
			scale</td>
			<td>
			Sartorius</td>
			<td>
			CP 3202 S</td>
		</tr>
		<tr>
			<td>
			stirred tank bioreactor with equipment</td>
			<td>
			Applikon Biotechnology</td>
			<td>
			2L Bioreactor set</td>
		</tr>
		<tr>
			<td>
			syringe</td>
			<td>
			Eppendorf</td>
			<td>
			Combitips Plus 5 mL</td>
		</tr>
	</tbody>
</table>
Table of Reagents:
<table border="1">
	<tbody>
		<tr>
			<td>
			Name of the reagent</td>
			<td>
			Company </td>
		</tr>
		<tr>
			<td>
			Acetic acid</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Disodium hydrogen phosphate</td>
			<td>
			Merck</td>
		</tr>
		<tr>
			<td>
			Ethanol (95%)</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Glucose monohydrate, (&alpha;-D-)</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Glucose oxidase (Typ II from Aspergillus niger)</td>
			<td>
			Sigma</td>
		</tr>
		<tr>
			<td>
			Hydrochloride acid (37 % w/v)</td>
			<td>
			Fiedel-de Ha&euml;n</td>
		</tr>
		<tr>
			<td>
			Hydrous magnesium silicate</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Monopotassium phosphate</td>
			<td>
			Merck</td>
		</tr>
		<tr>
			<td>
			o-dianoisidine dihydrochloride</td>
			<td>
			Sigma</td>
		</tr>
		<tr>
			<td>
			Peroxidase (Typ II from horseradish)</td>
			<td>
			Sigma</td>
		</tr>
		<tr>
			<td>
			Sodium acetate</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Sodium hydroxide</td>
			<td>
			Merck</td>
		</tr>
		<tr>
			<td>
			Sucrose, D-(+)</td>
			<td>
			Fluka</td>
		</tr>
		<tr>
			<td>
			Water (deionized)</td>
			<td>
			-</td>
		</tr>
	</tbody>
</table>
Table of Solutions and Medium Composition:
<table border="1">
	<tbody>
		<tr>
			<td>
			Solution</td>
			<td>
			Components</td>
			<td>
			Amount</td>
		</tr>
		<tr>
			<td>
			50 mM sodium acetate buffer (pH 6.5)</td>
			<td>
			Sodium acetate
			Bring to volume with deionized water
			Adjust at pH 6.5 with acetic acid</td>
			<td>
			4.1 g L-1</td>
		</tr>
		<tr>
			<td>
			0.05 M monopotassium phosphate solution</td>
			<td>
			Monopotassium phosphate
			Bring to volume with deionized water</td>
			<td>
			6.805 g L-1</td>
		</tr>
		<tr>
			<td>
			0.05 M disodium hydrogen phosphate solution</td>
			<td>
			Disodium hydrogen phosphate
			Bring to volume with deionized water</td>
			<td>
			7.1 g L-1</td>
		</tr>
		<tr>
			<td>
			0.05 M phosphate buffer (pH 7.0)</td>
			<td>
			0.05 M disodium hydrogen phosphate solution
			Bring to volume with 0.05 M monopotassium phosphate solution</td>
			<td>
			61.2 mL</td>
		</tr>
		<tr>
			<td>
			0.05 M phosphate buffer (pH 5.4)</td>
			<td>
			0.05M disodium hydrogen phosphate solution
			Bring to volume with 0.05 M monopotassium phosphate solution</td>
			<td>
			3 mL</td>
		</tr>
		<tr>
			<td>
			1.65 M sucrose solution</td>
			<td>
			D-(+)-sucrose
			Bring to volume with phosphate buffer (pH 5.4)</td>
			<td>
			564.8 g L-1</td>
		</tr>
		<tr>
			<td>
			reagent solution</td>
			<td>
			o-Dianisidin-Dihydrochlorid
			Ethanol (95%)</td>
			<td>
			25 mg
			10 mL</td>
		</tr>
		<tr>
			<td>
			Glucose reagent solution</td>
			<td>
			Glucose oxidase
			Peroxidase
			Phosphate buffer (pH 7.0)
			reagent solution</td>
			<td>
			10.5 mg
			3 mg
			90 mL
			10 mL</td>
		</tr>
	</tbody>
</table>

customization of aspergillus niger morphology through addition of talc micro particles

א פטריות פילמנטיות ניז&#39;ר ​​היא זן שימוש נרחב במגוון רחב של תהליכים תעשייתיים, החל מזון כדי תעשיית התרופות. אחד המאפיינים המסקרנים ביותר ובלתי נשלט לעתים קרובות של אורגניזם זה פילמנטיות הוא מורפולוגיה המורכב שלה. זה נע בין כדורי כדוריים צפופים כדי mycelia צמיגה (איור 1). פרמטרים שונים בתהליך וחומרי גלם ידועים להשפיע מורפולוגיה פטרייתי 1. מאז התפוקה האופטימלי וקושרת חזק עם צורה מורפולוגית ספציפית, מורפולוגיה פטרייתי לעיתים קרובות מהווה את צוואר הבקבוק של פריון הייצור התעשייתי. גישה קדימה אלגנטי ישר לשלוט במדויק צורה מורפולוגית הוא תוספת של מיקרו חלקיקים אורגניים מסיסים (כמו מגנזיום סיליקט להזרקה, אלומיניום אוקסיד או תחמוצת טיטניום סיליקט) עד בינוני תרבות תרומה ייצור האנזים גדל 2-6. מאז יש obvious קשר בין המורפולוגיה החלקיקים מיקרו תלוי ייצור האנזים רצוי מתמטית לקשר את הפרודוקטיביות ואת המראה הצורני. לכן תיאור כמותי מורפולוגי מדויק הוליסטית ממוקדת. לכן, אנו מציגים שיטה להפקת ולאפיין מיקרו תלויים החלקיקים מבנים מורפולוגיים, כדי לקשר בין המורפולוגיה פטרייתי עם פרודוקטיביות (איור 1) אשר ככל הנראה תורם להבנה טובה יותר של המורפוגנזה של מיקרואורגניזמים פילמנטיות. א זן רקומביננטי ניז&#39;ר ​​SKAn1015 מעובדת במשך 72 שעות ב L 3 עוררה bioreactor הטנק. על ידי תוספת של חלקיקי טלק מיקרו בריכוז של 1 גר &#39;/ ל&#39;, 3 גר &#39;/ ל&#39; ו - 10 גר &#39;/ ל&#39; לפני חיסון מגוון רחב של מבנים מורפולוגיים נוצר reproducibly. דגימות סטריליות נלקחים לאחר 24 שעות, 48 ו 72 לקביעת ההתקדמות הצמיחה והפעילות של האנזים מיוצר.המוצר שנוצר הוא אנזים גבוהה ערך β-fructofuranosidase, biocatalyst חשוב ליצירת ניאו הסוכר במזון או תעשיית התרופות, אשר מזרז בין היתר את התגובה של סוכרוז לגלוקוז 7-9. לכן, כימות של גלוקוז לאחר הוספת סוכרוז מרמז כמות fructofuranosidase-β מיוצר. כימות גלוקוז נעשה על ידי אלוהים / POD-Assay 10, אשר שונה לניתוח תפוקה גבוהה ב 96-גם מיקרו צלחות titer. מורפולוגיה פטרייתי לאחר 72 שעות נבדק על ידי מיקרוסקופ ומאופיינת על ידי ניתוח תמונה דיגיטלית. בעשותו כן, צורת החלקיקים גורמי המאקרו מורפולוגיה פטרייתי כמו בקוטר של Feret, באזור המוקרן, המערכת, המעגליות, יחס גובה, und מוצקות עגלגלות מחושבים עם התמונה קוד פתוח לעיבוד תוכנית ImageJ. הפרמטרים הרלוונטיים משולבים למספר מורפולוגיה מימדים (Mn) 11, המאפשרת אפיון מקיף שלפטרייתי המורפולוגיה. קשר הדוק של מספר מורפולוגיה ופריון מודגשים על ידי רגרסיה מתמטית.

Watch this Scientific Journal Video about Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles at JoVE.com

Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles

שיטה בדיוק להפיק באופן מקיף לאפיין המורפולוגיה של פטריות פילמנטיות<em&gt; אספרגילוס ניז&#39;ר</em&gt; מתוארת, המאפשר קשר מתמטי של המראה הצורני ואת הפרודוקטיביות.

התאמה אישית של אספרגילוס ניז&#39;ר מורפולוגיה באמצעות תוספת של חלקיקי טלק מיקרו

The filamentous fungus A. niger is a widely used strain in a broad range of industrial processes from food to pharmaceutical industry. One of the most ...

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Research

JoVE Journal

Immunology and Infection

Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles

Packaging HIV- or FIV-based Lentivector Expression Constructs &amp; Transduction of VSV-G Pseudotyped Viral Particles

As with standard plasmid vectors, it is possible to transfect lentivectors in plasmid form into cells with low-to-medium efficiency to obtain transient expression of effectors. Packaging lentiviral expression constructs into pseudoviral particles, however, enables up to 100% transduction, even with difficult-to-transfect cells, such as primary, stem, and differentiated cells. Moreover, the lentiviral delivery does not produce the specific cellular responses typically associated with chemical transfections, such as cell death resulting from toxicity of the transfection reagent 1, 2. When transduced into target cells, the lentiviral construct integrates into genomic DNA and provides stable expression of the small hairpin RNA (shRNA), cDNA, microRNA or reporter gene 3, 4. Target cells stably expressing the effector molecule can be isolated using a selectable marker contained in the expression vector construct such as puromycin or GFP. After pseudoviral particles infect target cells, they cannot replicate within target cells because the viral structural genes are absent and the long terminal repeats (LTRs) are designed to be self-inactivating upon transduction 5, 6.
There are three main components necessary for efficient lentiviral packaging 1, 5, 6, 7. 
1. The lentiviral expression vector that contains some of the genetic elements required for packaging, stable integration of the viral expression construct into genomic DNA, and expression of the effector or reporter. 
2. The lentiviral packaging plasmids that provide the proteins essential for transcription and packaging of an RNA copy of the expression construct into recombinant pseudoviral particles. This protocol uses the pPACK plasmids (SBI) that encode for gag, pol, and rev from the HIV or FIV genome and Vesicular Stomatitis Virus g protein (VSV-G) for the viral coat protein. 
3. 293TN producer cells (derived from HEK293 cells) that express the SV40 large T antigen, which is required for high-titer lentiviral production and a neomycin resistance gene, useful for reselecting the cells for maintenance.
An overview of the viral production protocol can be seen in Figure 1. Viral production starts by co-transfecting 293TN producer cells with the lentiviral expression vector and the packaging plasmids. Viral particles are secreted into the media. After 48-72 hours the cell culture media is harvested. Cellular debris is removed from the cell culture media, and the viral particles are precipitated by centrifugation with PEG-it for concentration. Produced lentiviral particles are then titered and can be used to transduce target cells. Details of viral titering are not included in this protocol, but can be found at:
<a href="http://www.systembio.com/downloads/global_titer_kit_web_090710.pdf" target="_blank">http://www.systembio.com/downloads/global_titer_kit_web_090710.pdf</a> 8.
This protocol has been optimized using the specific products indicated. Other reagents may be substituted, but the same results cannot be guaranteed.

Packaging HIV- or FIV-based Lentivector Expression Constructs & Transduction of VSV-G Pseudotyped Viral Particles

Lentiviral expression vectors are the most effective vehicles for stably expressing different effector molecules or reporter constructs in dividing and non-dividing mammalian cells and whole organisms. Here we provide a protocol on how to package lentivector expression constructs in pseudoviral particles and to transduce target cells using the pseudoviral particles.

אריזות ל-HIV או FIV מבוססי בונה הביטוי Lentivector שימוש התמרה של VSV-G חלקיקים נגיפיים Pseudotyped

As with standard plasmid vectors, it is possible to transfect lentivectors in plasmid form into cells with low-to-medium efficiency to obtain transient ...

Detection of Fluorescent Nanoparticle Interactions with Primary Immune Cell Subpopulations by Flow Cytometry

Engineered nanoparticles are endowed with very promising properties for therapeutic and diagnostic purposes. This work describes a fast and reliable method of analysis by flow cytometry to study nanoparticle interaction with immune cells. Primary immune cells can be easily purified from human or mouse tissues by antibody-mediated magnetic isolation. In the first instance, the different cell populations running in a flow cytometer can be distinguished by the forward-scattered light (FSC), which is proportional to cell size, and the side-scattered light (SSC), related to cell internal complexity. Furthermore, fluorescently labeled antibodies against specific cell surface receptors permit the identification of several subpopulations within the same sample. Often, all these features vary when cells are boosted by external stimuli that change their physiological and morphological state. Here, 50 nm FITC-SiO2 nanoparticles are used as a model to identify the internalization of nanostructured materials in human blood immune cells. The cell fluorescence and side-scattered light increase after incubation with nanoparticles allowed us to define time and concentration dependence of nanoparticle-cell interaction. Moreover, such protocol can be extended to investigate Rhodamine-SiO2 nanoparticle interaction with primary microglia, the central nervous system resident immune cells, isolated from mutant mice that specifically express the Green Fluorescent Protein (GFP) in the monocyte/macrophage lineage. Finally, flow cytometry data related to nanoparticle internalization into the cells have been confirmed by confocal microscopy.

Analysis of nanoparticle interaction with defined subpopulations of immune cells by flow cytometry.

איתור של פלורסנט אינטראקציות Nanoparticle עם אוכלוסיות ראשוניות של תא חיסון על ידי זרימת cytometry

Engineered nanoparticles are endowed with very promising properties for therapeutic and diagnostic purposes. This work describes a fast and reliable ...

Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes

Ebola viruses cause severe hemorrhagic fevers in humans and non-human primates, with case fatality rates as high as 90%. There are no approved vaccines or specific treatments for the disease caused by these viruses, and work with infectious Ebola viruses is restricted to biosafety level 4 laboratories, significantly limiting the research on these viruses. Lifecycle modeling systems model the virus lifecycle under biosafety level 2 conditions; however, until recently such systems have been limited to either individual aspects of the virus lifecycle, or a single infectious cycle. Tetracistronic minigenomes, which consist of Ebola virus non-coding regions, a reporter gene, and three Ebola virus genes involved in morphogenesis, budding, and entry (VP40, GP1,2, and VP24), can be used to produce replication and transcription-competent virus-like particles (trVLPs) containing these minigenomes. These trVLPs can continuously infect cells expressing the Ebola virus proteins responsible for genome replication and transcription, allowing us to safely model multiple infectious cycles under biosafety level 2 conditions. Importantly, the viral components of this systems are solely derived from Ebola virus and not from other viruses (as is, for example, the case in systems using pseudotyped viruses), and VP40, GP1,2 and VP24 are not overexpressed in this system, making it ideally suited for studying morphogenesis, budding and entry, although other aspects of the virus lifecycle such as genome replication and transcription can also be modeled with this system. Therefore, the tetracistronic trVLP assay represents the most comprehensive lifecycle modeling system available for Ebola viruses, and has tremendous potential for use in investigating the biology of Ebola viruses in future. Here, we provide detailed information on the use of this system, as well as on expected results.

Work with infectious Ebola viruses is restricted to biosafety level 4 laboratories. Tetracistronic minigenome-containing replication and transcription-competent virus like particles (trVLPs) represent a lifecycle modeling system that allows us to safely model multiple infectious cycles under biosafety level 2 conditions, relying exclusively on Ebola virus components.

דוגמנות מחזור החיים של נגיף האבולה תחת 2 תנאים ברמת בטיחות ביולוגיים עם חלקיקים כמו וירוס המכילים Tetracistronic Minigenomes

Ebola viruses cause severe hemorrhagic fevers in humans and non-human primates, with case fatality rates as high as 90%. There are no approved vaccines or ...

Optimization of a Quantitative Micro-neutralization Assay

The micro-neutralization (MN) assay is a standard technique for measuring the infectivity of the influenza virus and the inhibition of virus replication. In this study, we present the protocol of an imaging-based MN assay to quantify the true antigenic relationships between viruses. Unlike typical plaque reduction assays that rely on visible plaques, this assay quantitates the entire infected cell population of each well. The protocol matches the virus type or subtype with the selection of cell lines to achieve maximum infectivity, which enhances sample contrast during imaging and image processing. The introduction of quantitative titration defines the amount of input viruses of neutralization and enables the results from different experiments to be comparable. The imaging setup with a flatbed scanner and free downloadable software makes the approach high throughput, cost effective, user friendly, and easy to deploy in most laboratories. Our study demonstrates that the improved MN assay works well with the current circulating influenza A(H1N1)pdm09, A(H3N2), and B viruses, without being significantly influenced by amino acid substitutions in the neuraminidase (NA) of A(H3N2) viruses. It is particularly useful for the characterization of viruses that either grow to low HA titer and/or undergo an abortive infection resulting in an inability to form plaques in cultured cells.

This study describes an imaging-based micro-neutralization assay to analyze the antigenic relationships between viruses. The protocol employs a flatbed scanner and has four steps, including titration, titration quantitation, neutralization, and neutralization quantitation. The assay works well with current circulating influenza A(H1N1)pdm09, A(H3N2), and B viruses.

אופטימיזציה של Assay כמותי מיקרו-נטרול

The micro-neutralization (MN) assay is a standard technique for measuring the infectivity of the influenza virus and the inhibition of virus replication. ...

Production of Pseudotyped Particles to Study Highly Pathogenic Coronaviruses in a Biosafety Level 2 Setting

The protocol aims to generate coronavirus (CoV) spike (S) fusion protein pseudotyped particles with a murine leukemia virus (MLV) core and luciferase reporter, using a simple transfection procedure of the widely available HEK-293T cell line. Once formed and released from producer cells, these pseudovirions incorporate a luciferase reporter gene. Since they only contain the heterologous coronavirus spike protein on their surface, the particles behave like their native coronavirus counterparts for entry steps. As such, they are the excellent surrogates of native virions for studying viral entry into host cells. Upon successful entry and infection into target cells, the luciferase reporter gets integrated into the host cell genome and is expressed. Using a simple luciferase assay, transduced cells can be easily quantified. An important advantage of the procedure is that it can be performed in biosafety level 2 (BSL-2) facilities instead of BSL-3 facilities required for work with highly pathogenic coronaviruses such as Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus (SARS-CoV). Another benefit comes from its versatility as it can be applied to envelope proteins belonging to all three classes of viral fusion proteins, such as the class I influenza hemagglutinin (HA) and Ebola virus glycoprotein (GP), the class II Semliki forest virus E1 protein, or the class III vesicular stomatitis virus G glycoprotein. A limitation of the methodology is that it can only recapitulate virus entry steps mediated by the envelope protein being investigated. For studying other viral life cycle steps, other methods are required. Examples of the many applications these pseudotype particles can be used in include investigation of host cell susceptibility and tropism and testing the effects of virus entry inhibitors to dissect viral entry pathways used.

Here, we present a protocol to generate pseudotyped particles in a BSL-2 setting incorporating the spike protein of the highly pathogenic viruses Middle East respiratory syndrome and severe acute respiratory syndrome coronaviruses. These pseudotyped particles contain a luciferase reporter gene allowing quantification of virus entry into target host cells.

הפקה של חלקיקים Pseudotyped ללמוד מעוררת פתוגני באווירה אבטחה ברמה 2

The protocol aims to generate coronavirus (CoV) spike (S) fusion protein pseudotyped particles with a murine leukemia virus (MLV) core and luciferase ...

Measuring Phagocytosis of Aspergillus fumigatus Conidia by Human Leukocytes using Flow Cytometry

Invasive pulmonary infection by the mold Aspergillus fumigatus poses a great threat to immunocompromised patients. Inhaled fungal conidia (spores) are cleared from the human lung alveoli by being phagocytosed by innate monocytes and/or neutrophils. This protocol offers a fast and reliable measurement of phagocytosis by flow cytometry using fluorescein isothiocyanate (FITC)-labeled conidia for co-incubation with human leukocytes and subsequent counterstaining with an anti-FITC antibody to allow discrimination of internalized and cell-adherent conidia. Major advantages of this protocol are its rapidness, the possibility to combine the assay with cytometric analysis of other cell markers of interest, the simultaneous analysis of monocytes and neutrophils from a single sample and its applicability to other cell wall-bearing fungi or bacteria. Determination of percentages of phagocytosing leukocytes provides a means to microbiologists for evaluating virulence of a pathogen or for comparing pathogen wildtypes and mutants as well as to immunologists for investigating human leukocyte capabilities to combat pathogens.

Measuring Phagocytosis of Aspergillus fumigatus Conidia by Human Leukocytes using Flow Cytometry

This protocol provides a fast and reliable method to quantitatively measure phagocytosis of Aspergillus fumigatus conidia by human primary phagocytes using flow cytometry and to discriminate phagocytosis of conidia from mere adhesion to leukocytes.

מדידת פאיגוציטוזה של אספרגייוס מחטאים מחט על ידי האדם לוקיולוציטים באמצעות זרם ציטוטוטרי

Invasive pulmonary infection by the mold Aspergillus fumigatus poses a great threat to immunocompromised patients. Inhaled fungal conidia (spores) are ...

Production of High-Titer Infectious Influenza Pseudotyped Particles with Envelope Glycoproteins from Highly Pathogenic H5N1 and Avian H7N9 Viruses

The occasional direct transmission of the highly pathogenic avian influenza A virus H5N1 (HPAI H5N1) and H7N9 to humans and their lethality are serious public health issues and suggest the possibility of an epidemic. However, our molecular understanding of the virus is rudimentary, and it is necessary to study the biological properties of its envelope proteins as therapeutic targets and to develop strategies to control infection. We developed a solid viral pseudotyped particle (pp) platform to study avian influenza virus, including the functional analysis of its hemagglutinin (HA) and neuraminidase (NA) envelope glycoproteins, the reassortment characteristics of the HAs and NAs, receptors, tropisms, neutralizing antibodies, diagnosis, infectivity, for the purposes of drug development and vaccine design. Here, we describe an experimental procedure to establish pps with the envelope glycoproteins (HA, NA) from two influenza A strains (HAPI H5N1 and 2013 avian H7N9). Their generation is based on the capacity of some viruses, such as murine leukemia virus (MLV), to incorporate envelope glycoproteins into a pp. In addition, we also detail how these pps are quantified with RT-qPCR, and the infectivity detection of native and mismatched virus pps depending on the origin of the HAs and NAs. This system is highly flexible and adaptable and can be used to establish viral pps with envelope glycoproteins that can be incorporated in any other type of enveloped virus. Thus, this viral particle platform can be used to study wild viruses in many research investigations.

This protocol describes an experimental process to produce high-titer infectious viral pseudotyped particles (pp) with envelope glycoproteins from two influenza A strains and how to determine their infectivity. This protocol is highly adaptable to develop pps of any other type of enveloped viruses with different envelope glycoproteins.

ייצור של שפעת מדבקת גבוהה-Titer חלקיקים מוקלדים עם מעטפה גליקורופנס מH5N1 פתוגניים מאוד H7N9 וירוסים העופות

The occasional direct transmission of the highly pathogenic avian influenza A virus H5N1 (HPAI H5N1) and H7N9 to humans and their lethality are serious ...

Quantifying Human Norovirus Virus-like Particles Binding to Commensal Bacteria Using Flow Cytometry

Commensal bacteria are well established to impact infection of eukaryotic viruses. Direct binding between the pathogen and the host microbiome is responsible for altering infection for many of these viruses. Thus, characterizing the nature of virus-bacteria binding is a foundational step needed for elucidating the mechanism(s) by which bacteria alter viral infection. For human norovirus, commensal bacteria enhance B cell infection. The virus directly binds to these bacteria, indicating that this direct interaction is involved in the mechanism of infection enhancement. A variety of techniques can be used to quantify interactions between bacteria and viruses including scintillation counting of radiolabeled viruses and polymerase chain reaction (PCR). Both methods require the use of live virus, which may need to be generated in the laboratory. Currently, none of the established in vitro culture systems available for human norovirus are robust enough to allow for generation of highly concentrated viral stocks. In lieu of live virus, virus-like particles (VLPs) have been used to characterize the interactions between norovirus and bacteria. Herein a flow cytometry method is described with uses virus specific antibodies to quantify VLP binding to gram-negative and gram-positive bacteria. Inclusion of both bacteria only and isotype controls allowed for optimization of the assay to reduce background antibody binding and accurate quantification of VLP attachment to the bacteria tested. High VLP:bacterium ratios result in VLPs binding to large percentages of the bacterial population. However, when VLP quantities are decreased, the percent of bacteria bound also decreases. Ultimately, this method can be employed in future experiments elucidating the specific conditions and structural components that regulate norovirus:bacterial interactions.

The goal of this protocol is to quantify binding of the eukaryotic pathogen human norovirus to bacteria. After performing an initial virus-bacterium attachment assay, flow cytometry is used to detect virally-bound bacteria within the population.

כימות האדם Norovirus וירוס כריכת כריכה של חיידקים קומנדסאל באמצעות זרימה Cy, לנסות

Commensal bacteria are well established to impact infection of eukaryotic viruses. Direct binding between the pathogen and the host microbiome is ...

Infection of Zebrafish Larvae with Aspergillus Spores for Analysis of Host-Pathogen Interactions

Invasive aspergillosis (IA) is one of&#160;the most common fungal infections among immunocompromised individuals. Despite the availability of antifungal drugs, IA can cause &#62;50% mortality in infected immunocompromised patients. It is crucial to determine both host and pathogen factors that contribute to infection susceptibility and low survival rates in infected patients in order to develop novel therapeutics. Innate immune responses play a pivotal role in recognition and clearance of Aspergillus spores, though little is known about the exact cellular and molecular mechanisms. Reliable models are required to investigate detailed mechanistic interactions between the host and pathogen. The optical clarity and genetic tractability of zebrafish larvae make them an intriguing model&#160;to study host-pathogen interactions of multiple human bacterial and fungal infections in a live and intact host. This protocol describes a larval zebrafish Aspergillus infection model. First, Aspergillus spores are isolated and injected into the zebrafish hindbrain ventricle via microinjection. Then, chemical inhibitors such as immunosuppressive drugs are added directly to the larval water. Two methods to monitor the infection in injected larvae are described, including the 1) homogenization of larvae for colony forming unit (CFU) enumeration and 2) a repeated, daily live imaging setup. Overall, these techniques can be used to mechanistically analyze the progression of Aspergillus infection in vivo and can be applied to different host backgrounds and Aspergillus strains to interrogate host-pathogen interactions.

Infection of Zebrafish Larvae with Aspergillus Spores for Analysis of Host-Pathogen Interactions

This protocol describes an Aspergillus infection model in zebrafish larvae. Aspergillus spores are microinjected into the hindbrain of larvae, and chemical treatment is used to induce immunosuppression. Infection progression is monitored via a daily imaging setup to monitor fungal growth and immune responses as well as enumeration of live spores by colony forming unit plating.

זיהום זחלי זברה עם נבגי אספרגילוס לניתוח אינטראקציות מארח-פתוגן

Invasive aspergillosis (IA) is one of&#160;the most common fungal infections among immunocompromised individuals. Despite the availability of antifungal ...

Supervised Machine Learning for Semi-Quantification of Extracellular DNA in Glomerulonephritis

Glomerular cell death is a pathological feature of myeloperoxidase anti neutrophil cytoplasmic antibody associated vasculitis (MPO-AAV). Extracellular deoxyribonucleic acid (ecDNA) is released during different forms of cell death including apoptosis, necrosis, necroptosis, neutrophil extracellular traps (NETs) and pyroptosis. Measurement of this cell death is time consuming with several different biomarkers required to identify the different biochemical forms of cell death. Measurement of ecDNA is generally conducted in serum and urine as a surrogate for renal damage, not in the actual target organ where the pathological injury occurs. The current difficulty in investigating ecDNA in the kidney is the lack of methods for formalin fixed paraffin embedded tissue (FFPE) both experimentally and in archived human kidney biopsies. This protocol provides a summary of the steps required to stain for ecDNA in FFPE tissue (both human and murine), quench autofluorescence and measure the ecDNA in the resulting images using a machine learning tool from the publicly available open source ImageJ plugin trainable Weka segmentation. Trainable Weka segmentation is applied to ecDNA within the glomeruli where the program learns to classify ecDNA. This classifier is applied to subsequent acquired kidney images, reducing the need for manual annotations of each individual image. The adaptability of the trainable Weka segmentation is demonstrated further in kidney tissue from experimental murine anti-MPO glomerulonephritis (GN), to identify NETs and ecMPO, common pathological contributors to anti-MPO GN. This method provides objective analysis of ecDNA in kidney tissue that demonstrates clearly the efficacy in which the trainable Weka segmentation program can distinguish ecDNA between healthy normal kidney tissue and diseased kidney tissue. This protocol can easily be adapted to identify ecDNA, NETs and ecMPO in other organs.

Extracellular DNA (ecDNA) released during cell death is proinflammatory and contributes to inflammation. Measurement of ecDNA at the site of injury can determine the efficacy of therapeutic treatment in the target organ. This protocol describes the use of a machine learning tool to automate measurement of ecDNA in kidney tissue.

לימוד מכונה ללימוד למחצה של דנ א של מסחטות בפקאוסולפטיס

Glomerular cell death is a pathological feature of myeloperoxidase anti neutrophil cytoplasmic antibody associated vasculitis (MPO-AAV). Extracellular ...