המחברים מודים אלסנדרה מורטי דניס ושאדה עבור תרומה של חומר מסוגם. אנו מכירים את התמיכה הגדולה של קבוצת עבודה שב&quot;ס EHT במחלקה לפרמקולוגיה ניסיוני טוקסיקולוגיה של צעידה נמרצת. עבודתם של המחברים נתמך על ידי תרומות של DZHK (מרכז גרמנית למחקר קרדיו) ומשרד הגרמנית לחינוך ולמחקר (BMBF), קרן המחקר הגרמנית (DFG Es 88 / 12-1, HA 3423 / 5-1 ), המרכז הלאומי הבריטי עבור החלפת חידוד &amp; הפחתת בבעלי חיים למחקר (סדק IT NC3Rs להעניק 35,911-259,146), קרן הלב הבריטית RM / 13 / 30,157, המועצה האירופית למחקר (Advanced Grant IndivuHeart), קרן הלב גרמנית ואת פרייה und Hansestadt המבורג.

<ol>
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G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physiologic+force-frequency+response+in+engineered+heart+muscle+by+electromechanical+stimulation.">Physiologic force-frequency response in engineered heart muscle by electromechanical stimulation.</a> Biomaterials. 60, 82-91 (2015).</li><li>Eng, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autonomous+beating+rate+adaptation+in+human+stem+cell-derived+cardiomyocytes.">Autonomous beating rate adaptation in human stem cell-derived cardiomyocytes.</a> Nat Commun. 7, 10312 (2016).</li><li>Huebsch, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Miniaturized+iPS-Cell-Derived+Cardiac+Muscles+for+Physiologically+Relevant+Drug+Response+Analyses.">Miniaturized iPS-Cell-Derived Cardiac Muscles for Physiologically Relevant Drug Response Analyses.</a> Sci Rep. 6 (24726), 1-12 (2016).</li><li>Masumoto, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+myocardial+regenerative+potential+of+three-dimensional+engineered+cardiac+tissues+composed+of+multiple+human+iPS+cell-derived+cardiovascular+cell+lineages.">The myocardial regenerative potential of three-dimensional engineered cardiac tissues composed of multiple human iPS cell-derived cardiovascular cell lineages.</a> Sci Rep. 6 (29933), 1-10 (2016).</li><li>Ravenscroft, S. M., Pointon, A., Williams, A. W., Cross, M. J., Sidaway, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+Non-myocyte+Cells+Show+Enhanced+Pharmacological+Function+Suggestive+of+Contractile+Maturity+in+Stem+Cell+Derived+Cardiomyocyte+Microtissues.">Cardiac Non-myocyte Cells Show Enhanced Pharmacological Function Suggestive of Contractile Maturity in Stem Cell Derived Cardiomyocyte Microtissues.</a> Toxicol Sci. 152 (1), 99-112 (2016).</li><li>Zhang, J. H., Chung, T. D. Y., Oldenbutg, K. 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IM, TE ו AH הם מהמייסדים של GmbH טכנולוגיות EHT, גרמניה.

רקמת לב מהונדסים מציעה אפשרות רבת ערך בתיבת כלי מחקר לב וכלי דם. EHTs בפורמט 24-היטב הוכיח יקר עבור מודלי מחלה 8, 14, הקרנת בטיחות תרופת 7, 8, 10, 11, 15, או למ...

תופעות לוואי לב כגון תסמונת QT-induced סמים הארוכה הובילו משייכות שוק לאורך השנים האחרונות. הסטטיסטיקה מצביעה על כך כ -45% מכלל משיכות הן בשל השפעות לא רצויות על מערכת הלב וכלי הדם 1. כישלון התרופה הזו לאחר התהליך ואישור התפתחותי היקר הוא התרחיש הגרוע ביותר עבור חברות תרופות. מחלקות מחקר ופיתוח ולפיכך להתמקד זיהוי של תופעות קרדיווסקולריות רצויות כגון מוקדם. אם יש לך חששות כלכליים ואתיים, המאמצים לצמצום ניסויים בבעלי החיים ולהחליפם מבחני מיון חדשים במבחנה נמשכת. סט של מבחנים הוקמו כלולים מנהל המזון והתרופות בארה&quot;ב (FDA) סוכנות תרופות האירופית (EMA) הנחיות להערכת פרה-קלינית של שפעות תרופת proarrhythmic 2. הטכנולוגיה של תכנות מחדש תאים סומטיים ואחריו בידול שלתאי גזע אנושיים מושרים (hiPSC) שפרו שדה מחקר זה 3. כעת הוא מציע את האפשרות לסנן מועמדי תרופה חדשים על שריר לב אנושי במבחנה ונמנע בעיות עם הבדלים-מיני שאר. פרוטוקולי בידול לב אחרונים 4, 5 לספק היצע בלתי מוגבל של שריר לב בלי חשש אתי. עם זאת, המדידה של כוח ההתכווצות, החשוב ביותר המאופיין ביותר בפרמטר vivo של שריר לב, אינה מבוססת דיו. זה קשור הבגרות היחסית 6 של שריר לב הנגזרות תא גזע מושר האנושי (hiPSC-CM) בהשוואת cardiomyocyte המבוגר. התקדמות אפשרית היא להנדס רקמת לב 3 ממדים ממשפחות חד תאי 7 (רקמה לב מהונדס, EHT). פרוטוקול EHT מבוסס על הטבעה בעכברים יחידים או שריר לב אנושי 8 </sup&gt;, 9, 10 ב הידרוג&#39;ל הפיברין בין שני polydimethylsiloxane הגמיש (PDMS) הודעות 11 בפורמט 24-היטב. תוך כמה ימים cardiomyocytes להתחיל להתכווץ באופן ספונטני כמו תאים בודדים ולהתחיל להקים רשתות סלולריות. לאחר 7-10 ימים, התכווצויות מקרוסקופית של הרקמה כולה גלויות. במהלך תהליך זה מטריקס היא שופצה, אשר מובילה לירידה של קוטר ואורך. קיצור של תוצאות EHT כיפוף של PDMS לפרסם אפילו במנוחה, העמדת cardiomyocytes בתוך EHT בפיתוח עומס מתמשך. EHTs ממשיך לבצע התכווצויות שרירי auxotonic פני מספר שבועות. EHTs האדם להראות תגובות לגירויים פיסיולוגיים תרופתיים מציין התאמת הקרנה ומחלות תרופת דוגמנות 7. בכתב היד הזה אנו מציגים פרוטוקול חזק וקל עבור generatiעל של EHT האנושית, ואת ניתוח התכווצות אוטומטית של שינויים תלויי ריכוז של דפוס כיווץ בנוכחות מעכבי ערוץ hERG.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>EHT analysis intrument</td>
			<td>EHT Technologies GmbH</td>
			<td>A0001</td>
			<td>Software is included</td>
		</tr>
		<tr>
			<td>EHT PDMS rack</td>
			<td>EHT Technologies GmbH</td>
			<td>C0001</td>
			<td></td>
		</tr>
		<tr>
			<td>EHT PTFE spacer</td>
			<td>EHT Technologies GmbH</td>
			<td>C0002</td>
			<td></td>
		</tr>
		<tr>
			<td>EHT electrode</td>
			<td>EHT Technologies GmbH</td>
			<td>P0001</td>
			<td></td>
		</tr>
		<tr>
			<td>EHT pacing adapter/cable</td>
			<td>EHT Technologies GmbH</td>
			<td>P0002</td>
			<td></td>
		</tr>
		<tr>
			<td>24-well-plate</td>
			<td>Nunc</td>
			<td>144530</td>
			<td></td>
		</tr>
		<tr>
			<td>6 well-cell culture plate</td>
			<td>Nunc</td>
			<td>140675</td>
			<td></td>
		</tr>
		<tr>
			<td>15 ml falcon tube, graduated&#160;</td>
			<td>Sarstedt</td>
			<td>62,554,502</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell scraper</td>
			<td>Sarstedt</td>
			<td>831,830</td>
			<td></td>
		</tr>
		<tr>
			<td>Spinner flask</td>
			<td>Integra</td>
			<td>182 101</td>
			<td></td>
		</tr>
		<tr>
			<td>Stirrer Variomag/ Cimarec Biosystem Direct&#160;</td>
			<td>Thermo scientific</td>
			<td>70101</td>
			<td>Adjust rotor speed to 40 rpm</td>
		</tr>
		<tr>
			<td>T175 cell culture flask&#160;</td>
			<td>Sarstedt&#160;</td>
			<td>831,812,002</td>
			<td></td>
		</tr>
		<tr>
			<td>V-shaped sedimentation rack&#160;</td>
			<td>Custom made at UKE Hamburg</td>
			<td>na</td>
			<td></td>
		</tr>
		<tr>
			<td>10&#215; DMEM</td>
			<td>Gibco</td>
			<td>52100</td>
			<td></td>
		</tr>
		<tr>
			<td>1-Thioglycerol&#160;</td>
			<td>Sigma Aldrich</td>
			<td>M6145</td>
			<td></td>
		</tr>
		<tr>
			<td>2-Phospho-L-ascorbic acid trisodium salt</td>
			<td>Sigma Aldrich</td>
			<td>49752</td>
			<td></td>
		</tr>
		<tr>
			<td>Activin-A&#160;</td>
			<td>R&#38;D systems</td>
			<td>338-AC</td>
			<td></td>
		</tr>
		<tr>
			<td>Agarose&#160;</td>
			<td>Invitrogen</td>
			<td>15510-019</td>
			<td></td>
		</tr>
		<tr>
			<td>Aprotinin</td>
			<td>Sigma Aldrich</td>
			<td>A1153</td>
			<td></td>
		</tr>
		<tr>
			<td>Aqua ad injectabilia</td>
			<td>Baxter GmbH</td>
			<td>1428</td>
			<td></td>
		</tr>
		<tr>
			<td>B27 PLUS insulin&#160;</td>
			<td>Gibco</td>
			<td>17504-044</td>
			<td></td>
		</tr>
		<tr>
			<td>BMP-4</td>
			<td>R&#38;D systems</td>
			<td>314-BP</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase II&#160;</td>
			<td>Worthington</td>
			<td>LS004176</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Biochrom</td>
			<td>F0415</td>
			<td></td>
		</tr>
		<tr>
			<td>DMSO&#160;</td>
			<td>Sigma Aldrich</td>
			<td>D4540</td>
			<td></td>
		</tr>
		<tr>
			<td>DNase II, type V (from bovine spleen)</td>
			<td>Sigma&#160;</td>
			<td>D8764</td>
			<td></td>
		</tr>
		<tr>
			<td>Dorsomorphin&#160;</td>
			<td>abcam</td>
			<td>ab120843</td>
			<td></td>
		</tr>
		<tr>
			<td>EDTA&#160;</td>
			<td>Roth</td>
			<td>8043.2</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal calf serum</td>
			<td>Gibco</td>
			<td>10437028</td>
			<td></td>
		</tr>
		<tr>
			<td>FGF2</td>
			<td>Miltenyi Biotec</td>
			<td>130-104-921</td>
			<td></td>
		</tr>
		<tr>
			<td>Fibrinogen (bovine)</td>
			<td>Sigma Aldrich</td>
			<td>F8630</td>
			<td></td>
		</tr>
		<tr>
			<td>Geltrex&#160;</td>
			<td>Gibco</td>
			<td>A1413302</td>
			<td>For coating: 1:200 dilution</td>
		</tr>
		<tr>
			<td>HBSS w/o Ca2+/Mg2+&#160;</td>
			<td>Gibco</td>
			<td>14175-053</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES&#160;</td>
			<td>Roth</td>
			<td>9105.4</td>
			<td></td>
		</tr>
		<tr>
			<td>Horse serum</td>
			<td>Life technologies</td>
			<td>26050088</td>
			<td></td>
		</tr>
		<tr>
			<td>Human serum albumin&#160;</td>
			<td>Biological Industries</td>
			<td>05-720-1B</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulin, human</td>
			<td>Sigma Aldrich</td>
			<td>I9278</td>
			<td></td>
		</tr>
		<tr>
			<td>L-Glutamin</td>
			<td>Gibco</td>
			<td>25030-024</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipidmix&#160;</td>
			<td>Sigma Aldrich</td>
			<td>L5146</td>
			<td></td>
		</tr>
		<tr>
			<td>Matrigel</td>
			<td>BD Biosciences</td>
			<td>354234</td>
			<td>For EHT reconsitutionmix.</td>
		</tr>
		<tr>
			<td>N-Benzyl-p-Toluenesulfonamide</td>
			<td>TCI</td>
			<td>B3082-25G</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS w/o MgCl2/CaCl2</td>
			<td>Biochrom</td>
			<td>14190</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin</td>
			<td>Gibco</td>
			<td>15140</td>
			<td></td>
		</tr>
		<tr>
			<td>Pluronic F-127&#160;</td>
			<td>Sigma Aldrich</td>
			<td>P2443</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyvinyl alcohol&#160;</td>
			<td>Sigma Aldrich</td>
			<td>P8136</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI 1640&#160;</td>
			<td>Gibco</td>
			<td>21875</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium selenite</td>
			<td>Sigma Aldrich</td>
			<td>S5261</td>
			<td></td>
		</tr>
		<tr>
			<td>TGF&#223;1</td>
			<td>Peprotech</td>
			<td>100-21</td>
			<td></td>
		</tr>
		<tr>
			<td>Thrombin</td>
			<td>Sigma Aldrich</td>
			<td>T7513</td>
			<td></td>
		</tr>
		<tr>
			<td>Transferrin&#160;</td>
			<td>Sigma Aldrich</td>
			<td>T8158</td>
			<td></td>
		</tr>
		<tr>
			<td>Y-27632</td>
			<td>Biorbyt</td>
			<td>orb6014</td>
			<td></td>
		</tr>
		<tr>
			<td>hiPSC</td>
			<td>Custom made at UKE hamburg</td>
			<td>na</td>
			<td></td>
		</tr>
		<tr>
			<td>iCell cardiomyocytes kit</td>
			<td>Cellular Dynamics International</td>
			<td>CMC-100-010-001</td>
			<td></td>
		</tr>
		<tr>
			<td>Pluricyte cardiomyocyte kit</td>
			<td>Pluriomics</td>
			<td>PCK-1.5</td>
			<td></td>
		</tr>
		<tr>
			<td>Cor.4U - HiPSC cardiomyocytes kit</td>
			<td>Axiogenesis AG</td>
			<td>Ax-C-HC02-FR3</td>
			<td></td>
		</tr>
		<tr>
			<td>Cellartis cardiomyocytes</td>
			<td>Takara Bio USA, Inc.</td>
			<td>Y10075</td>
			<td></td>
		</tr>
	</tbody>
</table>

automated contraction analysis of human engineered heart tissue for cardiac drug safety screening

הנדסת רקמות לב מתארת ​​טכניקות להוות שלוש רקמות מהונדסות מניב כוח ממדים. לשם יישום הנהלים אלה במחקר בסיסי ופיתוח תרופות פרה-קליני, חשוב לפתח פרוטוקולים עבור דור אוטומטי וניתוחים בתנאים סטנדרטיים. כאן, אנו מציגים טכניקה ליצירת רקמת לב Engineered (EHT) מ cardiomyocytes של מינים שונים (חולדה, עכבר, אדם). הטכניקה מתבססת על מכלול של א-ג&#39;ל הפיברין המכיל cardiomyocytes ניתק בין polydimethylsiloxane אלסטי (PDMS) הודעות בפורמט 24-היטב. שלוש ממדי, מניב כוח EHTs מהווה בתוך שבועות אחרי הליהוק. הליך זה מאפשר לדור של כמה מאות EHTs בשבוע מוגבל מבחינה טכנית רק על ידי הזמינות של שריר הלב (0.4-1.0 x 10 6 / EHT). הערכת התכווצויות שרירי auxotonic מתבצעת בתא דגירה שונה עם mechanמשתלב iCal עבור צלחות 24-היטב ומצלמה ממוקמת על גבי תא זה. תוכנה שולטת במצלמה עבר על מערכת צירים XYZ לכל EHT. התכווצויות EHT מזוהות על ידי אלגוריתם זיהוי דמות אוטומטי, וכוח מחושב על בסיס קיצור של EHT ואת הנטייה אלסטי וגיאומטריה של הודעות PDMS. הליך זה מאפשר ניתוח אוטומטי של מספרים גבוהים של EHT בתנאים סטנדרטיים סטרילי. זיהוי האמין של שפעות תרופה על התכווצות cardiomyocyte הוא קריטי להתפתחות ופרמקולוגיה בטיחות תרופת לב. אנו מדגימים, עם הדוגמא של E-4031 מעכב ערוץ hERG, שמערכת EHT האנושית משכפלת תגובות תרופה על קינטיקה התכווצות של הלב האנושי, המציין שזה יהיה כלי מבטיח עבור הקרנת בטיחות תרופת לב.

בידול לב הכנת EHT HiPSC הורחב על מטריצה ​​הממברנה במרתף מופחת צמיחת גורם, ניתק עם EDTA וגופי Embryoid (EBS) נוצרו צלוחיות טווים לילה. לאחר אינדוקצית mesodermal במשך שלושה ימים, בידול לב החל עם מעכב Wnt. לאחר ~ 17 ימים...

Watch this Scientific Journal Video about Automated Contraction Analysis of Human Engineered Heart Tissue for Cardiac Drug Safety Screening at JoVE.com

Automated Contraction Analysis of Human Engineered Heart Tissue for Cardiac Drug Safety Screening

כאן, אנו מציגים את הדור של רקמת לב מהונדסים אנושי מתאי גזע מושרים (hiPSC) -derived cardiomyocytes. אנו מציגים שיטה לנתח בכוח התכווצות ושינוי למופת של דפוס כיווץ ידי מעכב ערוץ hERG E-4031. שיטה זו מציגה רמה גבוהה של חוסן ויכולת התאמת הקרנת סמי לב.

ניתוח התכווצות האוטומטי של רקמת לב Engineered האנוש להקרנת בטיחות תרופת לב

Cardiac tissue engineering describes techniques to constitute three dimensional force-generating engineered tissues. For the implementation of these ...

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Cardiovascular Drugs: Antiarrhythmic and Heart Failure Drugs

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12.6K Views.  University Medical Center Hamburg-Eppendorf and DZHK (German Center for Cardiovascular Research).  כאן, אנו מציגים את הדור של רקמת לב מהונדסים אנושי מתאי גזע מושרים (hiPSC) -derived cardiomyocytes. אנו מציגים שיטה לנתח בכוח התכווצות ושינוי למופת של דפוס כיווץ ידי מעכב ערוץ hERG E-4031. שיטה זו מציגה רמה גבוהה של חוסן ויכולת התאמת הקרנת סמי לב. 

Video: Automated Contraction Analysis of Human Engineered Heart Tissue for Cardiac Drug Safety Screening

Bioluminescence Imaging for Assessment of Immune Responses Following Implantation of Engineered Heart Tissue (EHT)

Various techniques of cardiac tissue engineering have been pursued in the past decades including scaffolding strategies using either native or bioartificial scaffold materials, entrapment of cardiac myocytes in hydrogels such as fibrin or collagen and stacking of myocyte monolayers 1. These concepts aim at restoration of compromised cardiac function (e.g. after myocardial infarction) or as experimental models (e.g. predictive toxicology and substance screening or disease modelling). Precise monitoring of cell survival after implantation of engineered heart tissue (EHT) has now become possible using in-vivo bioluminescence imaging (BLI) techniques 2. Here we describe the generation of fibrin-based EHT from a transgenic rat strain with ubiquitous expression of firefly luciferase (ROSA/luciferase-LEW Tg; 3). Implantation is performed into the greater omentum of different rat strains to assess immune responses of the recipient organism following EHT implantation. Comparison of results generated by BLI and the Enzyme Linked Immuno Spot Technique (ELISPOT) confirm the usability of BLI for the assessment of immune responses.

Bioluminescence Imaging for Assessment of Immune Responses Following Implantation of Engineered Heart Tissue EHT

This video demonstrates the use of in vivo bioluminescence imaging to study immune responses after implantation of Engineered Heart Tissue (EHT) in rats.

פליטת אור הדמיה עבור הערכת התגובה החיסונית לאחר השתלת רקמת לב הנדסי (EHT)

Various techniques of cardiac tissue engineering have been pursued in the past decades including scaffolding strategies using either native or ...

Self-reporting Scaffolds for 3-Dimensional Cell Culture

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting 3D cellular construct can often be more relevant to studying the molecular events and cell-cell interactions than similar experiments studied in 2D. To create effective 3D cultures with high cell viability throughout the scaffold the culture conditions such as oxygen and pH need to be carefully controlled as gradients in analyte concentration can exist throughout the 3D construct. Here we describe the methods of preparing biocompatible pH responsive sol-gel nanosensors and their incorporation into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds along with their subsequent preparation for the culture of mammalian cells. The pH responsive scaffolds can be used as tools to determine microenvironmental pH within a 3D cellular construct. Furthermore, we detail the delivery of pH responsive nanosensors to the intracellular environment of mammalian cells whose growth was supported by electrospun PLGA scaffolds. The cytoplasmic location of the pH responsive nanosensors can be utilized to monitor intracellular pH (pHi) during ongoing experimentation.

Biocompatible pH responsive sol-gel nanosensors can be incorporated into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds. The produced self-reporting scaffolds can be used for in&#160;situ monitoring of microenvironmental conditions whilst culturing cells upon the scaffold. This is beneficial as the 3D cellular construct can be monitored in real-time without disturbing the experiment.

פיגומים דיווח עצמי לתרבית תאים 3-Dimensional

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting ...

Analysis of Tubular Membrane Networks in Cardiac Myocytes from Atria and Ventricles

In cardiac myocytes a complex network of membrane tubules - the transverse-axial tubule system (TATS) - controls deep intracellular signaling functions. While the outer surface membrane and associated TATS membrane components appear to be continuous, there are substantial differences in lipid and protein content. In ventricular myocytes (VMs), certain TATS components are highly abundant contributing to rectilinear tubule networks and regular branching 3D architectures. It is thought that peripheral TATS components propagate action potentials from the cell surface to thousands of remote intracellular sarcoendoplasmic reticulum (SER) membrane contact domains, thereby activating intracellular Ca2+ release units (CRUs). In contrast to VMs, the organization and functional role of TATS membranes in atrial myocytes (AMs) is significantly different and much less understood. Taken together, quantitative structural characterization of TATS membrane networks in healthy and diseased myocytes is an essential prerequisite towards better understanding of functional plasticity and pathophysiological reorganization. Here, we present a strategic combination of protocols for direct quantitative analysis of TATS membrane networks in living VMs and AMs. For this, we accompany primary cell isolations of mouse VMs and/or AMs with critical quality control steps and direct membrane staining protocols for fluorescence imaging of TATS membranes. Using an optimized workflow for confocal or superresolution TATS image processing, binarized and skeletonized data are generated for quantitative analysis of the TATS network and its components. Unlike previously published indirect regional aggregate image analysis strategies, our protocols enable direct characterization of specific components and derive complex physiological properties of TATS membrane networks in living myocytes with high throughput and open access software tools. In summary, the combined protocol strategy can be readily applied for quantitative TATS network studies during physiological myocyte adaptation or disease changes, comparison of different cardiac or skeletal muscle cell types, phenotyping of transgenic models, and pharmacological or therapeutic interventions.

In cardiac myocytes, tubular membrane structures form intracellular networks. We describe optimized protocols for i) isolation of myocytes from mouse heart including quality control, ii) live cell staining for state-of-the-art fluorescence microscopy, and iii) direct image analysis to quantify the component complexity and the plasticity of intracellular membrane networks.

ניתוח של Tubular ממברנה רשתות בלב myocytes מאטרייה וחדרי לב

In cardiac myocytes a complex network of membrane tubules - the transverse-axial tubule system (TATS) - controls deep intracellular signaling functions. ...

Hollow Fiber Bioreactors for In Vivo-like Mammalian Tissue Culture

Tissue culture has been used for over 100 years to study cells and responses ex vivo. The convention of this technique is the growth of anchorage dependent cells on the 2-dimensional surface of tissue culture plastic. More recently, there is a growing body of data demonstrating more in vivo-like behaviors of cells grown in 3-dimensional culture systems. This manuscript describes in detail the set-up and operation of a hollow fiber bioreactor system for the in vivo-like culture of mammalian cells. The hollow fiber bioreactor system delivers media to the cells in a manner akin to the delivery of blood through the capillary networks in vivo. The system is designed to fit onto the shelf of a standard CO2 incubator and is simple enough to be set-up by any competent cell biologist with a good understanding of aseptic technique. The systems utility is demonstrated by culturing the hepatocarcinoma cell line HepG2/C3A for 7 days. Further to this and in line with other published reports on the functionality of cells grown in 3-dimensional culture systems the cells are shown to possess increased albumin production (an important hepatic function) when compared to standard 2-dimensional tissue culture.

Hollow Fiber Bioreactors for In Vivo-like Mammalian Tissue Culture

The functional behavior of cells in culture can be improved by culturing in more in vivo-like 3-dimensional culture environments16-21. This manuscript describes the set-up and operation of a hollow fiber bioreactor system for in vivo-like mammalian tissue culture.

ריאקטורים סיבים חלולים עבור<em&gt; In vivo</em&gt; תרבות הרקמות היונקת-כמו

Tissue culture has been used for over 100 years to study cells and responses ex vivo. The convention of this technique is the growth of anchorage ...

Construction of Defined Human Engineered Cardiac Tissues to Study Mechanisms of Cardiac Cell Therapy

Human cardiac tissue engineering can fundamentally impact therapeutic discovery through the development of new species-specific screening systems that replicate the biofidelity of three-dimensional native human myocardium, while also enabling a controlled level of biological complexity, and allowing non-destructive longitudinal monitoring of tissue contractile function. Initially, human engineered cardiac tissues (hECT) were created using the entire cell population obtained from directed differentiation of human pluripotent stem cells, which typically yielded less than 50% cardiomyocytes. However, to create reliable predictive models of human myocardium, and to elucidate mechanisms of heterocellular interaction, it is essential to accurately control the biological composition in engineered tissues. 
To address this limitation, we utilize live cell sorting for the cardiac surface marker SIRP&#945; and the fibroblast marker CD90 to create tissues containing a 3:1 ratio of these cell types, respectively, that are then mixed together and added to a collagen-based matrix solution. Resulting hECTs are, thus, completely defined in both their cellular and extracellular matrix composition.
Here we describe the construction of defined hECTs as a model system to understand mechanisms of cell-cell interactions in cell therapies, using an example of human bone marrow-derived mesenchymal stem cells (hMSC) that are currently being used in human clinical trials. The defined tissue composition is imperative to understand how the hMSCs may be interacting with the endogenous cardiac cell types to enhance tissue function. A bioreactor system is also described that simultaneously cultures six hECTs in parallel, permitting more efficient use of the cells after sorting.

This manuscript describes the creation of defined engineered cardiac tissues using surface marker expression and cell sorting. The defined tissues can then be used in a multi-tissue bioreactor to investigate mechanisms of cardiac cell therapy in order to provide a functional, yet controlled, model system of the human heart.

בניית רקמות לב Engineered האנושית תחם לחקור מנגנונים של טיפול בתאי לב

Human cardiac tissue engineering can fundamentally impact therapeutic discovery through the development of new species-specific screening systems that ...

Neonatal Cardiac Scaffolds: Novel Matrices for Regenerative Studies

The only definitive therapy for end stage heart failure is orthotopic heart transplantation. Each year, it is estimated that more than 100,000 donor hearts are needed for cardiac transplantation procedures in the United States1-2. Due to the limited numbers of donors, only approximately 2,400 transplants are performed each year in the U.S.2. Numerous approaches, from cell therapy studies to implantation of mechanical assist devices, have been undertaken, either alone or in combination, in an attempt to coax the heart to repair itself or to rest the failing heart3. In spite of these efforts, ventricular assist devices are still largely used for the purpose of bridging to transplantation and the utility of cell therapies, while they hold some curative promise, is still limited to clinical trials. Additionally, direct xenotransplantation has been attempted but success has been limited due to immune rejection. Clearly, another strategy is required to produce additional organs for transplantation and, ideally, these organs would be autologous so as to avoid the complications associated with rejection and lifetime immunosuppression. Decellularization is a process of removing resident cells from tissues to expose the native extracellular matrix (ECM) or scaffold. Perfusion decellularization offers complete preservation of the three dimensional structure of the tissue, while leaving the bulk of the mechanical properties of the tissue intact4. These scaffolds can be utilized for repopulation with healthy cells to generate research models and, possibly, much needed organs for transplantation. We have exposed the scaffolds from neonatal mice (P3), known to retain remarkable cardiac regenerative capabilities,5-8 to detergent mediated decellularization and we repopulated these scaffolds with murine cardiac cells. These studies support the feasibility of engineering a neonatal heart construct. They further allow for the investigation as to whether the ECM of early postnatal hearts may harbor cues that will result in improved recellularization strategies.

In these studies, we provide methodology for novel, neonatal, murine cardiac scaffolds for use in regenerative studies.

Neonatal לב פיגומים: מטריצות Novel ללימודי הרגנרציה

The only definitive therapy for end stage heart failure is orthotopic heart transplantation.  Each year, it is estimated that more than 100,000 donor ...

Use of High-Throughput Automated Microbioreactor System for Production of Model IgG1 in CHO Cells

Automated microscale bioreactors (15 mL) can be a useful tool for cell culture engineers. They facilitate the simultaneous execution of a wide variety of experimental conditions while minimizing potential process variability. Applications of this approach include: clone screening, temperature and pH shifts,&#160;media and supplement optimization. Furthermore, the small reactor volumes are conducive to large Design of Experiments that investigate a wide range of conditions. This allows upstream processes to be significantly optimized before scale-up where experimentation is more limited in scope due to time and economic constraints. Automated microscale bioreactor systems offer various advantages over traditional small scale cell culture units, such as shake flasks or spinner flasks. However, during pilot scale process development&#160;significant care must be taken to ensure that these advantages are realized. When run with care, the system can enable high level automation, can be programmed to run DOE&#39;s with a higher number of variables&#160;and can reduce sampling time when integrated with a nutrient analyzer or cell counter. Integration of the expert-derived heuristics presented here, with current automated microscale bioreactor experiments can minimize common pitfalls that hinder meaningful results. In the extreme, failure to adhere to the principles laid out here can lead to equipment damage that requires expensive repairs. Furthermore, the microbioreactor systems have small culture volumes&#160;making characterization of cell culture conditions difficult. The number and amount of samples taken in-process in batch mode culture is limited as operating volumes cannot fall below 10 mL. This method will discuss the benefits and drawbacks of microscale bioreactor systems.

A detailed protocol for the concurrent operation of 48 parallel cell cultures under varied conditions in a microbioreactor system is presented. Cell culture process, harvest and subsequent antibody titer analysis are described.

השימוש תפוקה גבוהה אוטומטית Microbioreactor מערכת לייצור של מודל IgG1 בתאים צ'ו

Automated microscale bioreactors (15 mL) can be a useful tool for cell culture engineers. They facilitate the simultaneous execution of a wide variety of ...

Preparation of Mesh-Shaped Engineered Cardiac Tissues Derived from Human iPS Cells for In Vivo Myocardial Repair

The current protocol describes methods to generate scalable, mesh-shaped engineered cardiac tissues (ECTs) composed of cardiovascular cells derived from human induced pluripotent stem cells (hiPSCs), which are developed towards the goal of clinical use. HiPSC-derived cardiomyocytes, endothelial cells, and vascular mural cells are mixed with gel matrix and then poured into a polydimethylsiloxane (PDMS) tissue mold with rectangular internal staggered posts. By culture day 14 ECTs mature into a 1.5 cm x 1.5 cm mesh structure with 0.5 mm diameter myofiber bundles. Cardiomyocytes align to the long-axis of each bundle and spontaneously beat synchronously. This approach can be scaled up to a larger (3.0 cm x 3.0 cm) mesh ECT while preserving construct maturation and function. Thus, mesh-shaped ECTs generated from hiPSC-derived cardiac cells may be feasible for cardiac regeneration paradigms.

The present protocol generates mesh-shaped engineered cardiac tissues containing cardiovascular cells derived from human induced pluripotent stem cells to allow the investigation of cell implantation therapy for heart diseases.

הכנת רקמות לב מהונדסות בצורת רשת נגזר תאי iPS אנושיים לתיקון שריר הלב Vivo

The current protocol describes methods to generate scalable, mesh-shaped engineered cardiac tissues (ECTs) composed of cardiovascular cells derived from ...

Cardiac Spheroids as in vitro Bioengineered Heart Tissues to Study Human Heart Pathophysiology

Despite several advances in cardiac tissue engineering, one of the major challenges to overcome remains the generation of a fully functional vascular network comprising several levels of complexity to provide oxygen and nutrients within bioengineered heart tissues. Our laboratory has developed a three-dimensional in vitro model of the human heart, known as the "cardiac spheroid" or "CS". This presents biochemical, physiological, and pharmacological features typical of the human heart and is generated by co-culturing its three major cell types, such as cardiac myocytes, endothelial cells, and fibroblasts. Human induced pluripotent stem cells-derived cardiomyocytes (hiPSC-CMs or iCMs) are co-cultured at ratios approximating the ones found in vivo with human cardiac fibroblasts (HCFs) and human coronary artery endothelial cells (HCAECs) in hanging drop culture plates for three to four days. The confocal analysis of CSs stained with antibodies against cardiac Troponin T, CD31 and vimentin (markers for cardiac myocytes, endothelial cells and fibroblasts, respectively) shows that CSs present a complex endothelial cell network, resembling the native one found in the human heart. This is confirmed by the 3D rendering analysis of these confocal images. CSs also present extracellular matrix (ECM) proteins typical of the human heart, such as collagen type IV, laminin and fibronectin. Finally, CSs present a contractile activity measured as syncytial contractility closer to the one typical of the human heart compared to CSs that contain iCMs only. When treated with a cardiotoxic anti-cancer agent, such as doxorubicin (DOX, used to treat leukemia, lymphoma and breast cancer), the viability of DOX-treated CSs is significantly reduced at 10 &#181;M genetic and chemical inhibition of endothelial nitric oxide synthase, a downstream target of DOX in HCFs and HCAECs, reduced its toxicity in CSs. Given these unique features, CSs are currently used as in vitro models to study heart biochemistry, pathophysiology, and pharmacology.

This protocol aims to fabricate 3D cardiac spheroids (CSs) by co-culturing cells in hanging drops.&#160;Collagen-embedded CSs are treated with doxorubicin (DOX, a cardiotoxic agent) at physiological concentrations to model heart failure. In vitro testing using DOX-treated CSs may be used to identify novel therapies for heart failure patients.

ספרואידים לב כמו במבחנה ביו מהונדסת רקמות לב לחקור פתופיזיולוגיה לב אנושי

Despite several advances in cardiac tissue engineering, one of the major challenges to overcome remains the generation of a fully functional vascular ...

Developing 3D Organized Human Cardiac Tissue within a Microfluidic Platform

The leading cause of death worldwide persists as cardiovascular disease (CVD). However, modeling the physiological and biological complexity of the heart muscle, the myocardium, is notoriously difficult to accomplish in vitro. Mainly, obstacles lie in the need for human cardiomyocytes (CMs) that are either adult or exhibit adult-like phenotypes and can successfully replicate the myocardium&#39;s cellular complexity and intricate 3D architecture. Unfortunately, due to ethical concerns and lack of available primary patient-derived human cardiac tissue, combined with the minimal proliferation of CMs, the sourcing of viable human CMs has been a limiting step for cardiac tissue engineering. To this end, most research has transitioned toward cardiac differentiation of human induced pluripotent stem cells (hiPSCs) as the primary source of human CMs, resulting in the wide incorporation of hiPSC-CMs within in vitro assays for cardiac tissue modeling.
Here in this work, we demonstrate a protocol for developing a 3D mature stem cell-derived human cardiac tissue within a microfluidic device. We specifically explain and visually demonstrate the production of a 3D in vitro anisotropic cardiac tissue-on-a-chip model from hiPSC-derived CMs. We primarily describe a purification protocol to select for CMs, the co-culture of cells with a defined ratio via mixing CMs with human CFs (hCFs), and suspension of this co-culture within the collagen-based hydrogel. We further demonstrate the injection of the cell-laden hydrogel within our well-defined microfluidic device, embedded with staggered elliptical microposts that serve as surface topography to induce a high degree of alignment of the surrounding cells and the hydrogel matrix, mimicking the architecture of the native myocardium. We envision that the proposed 3D anisotropic cardiac tissue-on-chip model is suitable for fundamental biology studies, disease modeling, and, through its use as a screening tool, pharmaceutical testing.

The goal of this protocol is to explain and demonstrate the development of a three-dimensional (3D) microfluidic model of highly aligned human cardiac tissue, composed of stem cell-derived cardiomyocytes co-cultured with cardiac fibroblasts (CFs) within a biomimetic, collagen-based hydrogel, for applications in cardiac tissue engineering, drug screening, and disease modeling.

פיתוח רקמת לב אנושית מאורגנת תלת מימדית בתוך פלטפורמה מיקרופלואידית

The leading cause of death worldwide persists as cardiovascular disease (CVD). However, modeling the physiological and biological complexity of the heart ...