מחקר זה מומן על ידי NIH 1R01HL140239-01 ל- AMC. ברצוננו להודות למרכז להדמיית תאים באוניברסיטת דרקסל.

למחברים אין מה לחשוף.

פרוטוקול זה הוא הראשון מסוגו להדפסה ביולוגית של ספרואידים בארכיטקטורת תלת-ממד שלהם לתרבות משותפת עם תאי אנדותל גם בארכיטקטורת תלת-ממד שלהם. צעדי פרוטוקול קריטיים כוללים היווצרות ראשונית של ספירואידים אפיתל השד ורשתות HUVEC. יש לנקוט משנה זהירות בהאכלת ספירואידים אפיתל, שכן הם מופרעים בקלו?...

מודלים של גידולים במבחנה במבחנה הם כלים חיוניים למחקר מכני של צמיחת סרטן וגרורות. עבור סרטן השד בפרט, תאי אפיתל השד בתרבית Matrigel לארגן לתוך ספרואידים מקוטבים הדומים יותר לארכיטקטורה acinus ממארי in vivo1,2,3,4,5,6,7,8. 3D תרבית תאי אפיתל השד משפיע גם על תפקוד התא, עם תרביות 3D מראה הבדלים אפנון קולטן אפידרמיס (EGF)8,9; פונקציית אונקוגן, כולל ErbB210; צמיחה ואפופטוזיס איתות11,12; והתנגדותכימותרפית 13,14. תאי אנדותל כלי דם מגיבים באופן דומה באופן שונה לגירויים סביבתיים בתלת מימד לעומת תרבות דו מימדית מסורתית15,16,17,18. עם זאת, רוב ההבנה של אינטראקציות אנדותל ושד כלי הדם אפיתל מגיע תרבות 2D באמצעות בינוני מותנה או Transwell מוסיף, או מודלים 3D שבו שני סוגי התאים מופרדים פיזית19,20,21,22,23. מודלים אלה של תרבות משותפת מספקים תובנה פיזיולוגית מוגבלת, שכן הן תרבות 3D והן מגע תאים הם קריטיים אנדותל כלי הדם – אינטראקציות תא אפיתל השד24,25,26.
מודלים סרטן 3D כבר מפוברק באמצעות מגוון רחב של טכניקות, כולל היווצרות ספירואיד טיפה תלויה, bioprinting, הרכבה מגנטית, ותרבות בתוך הידרוג'לים או על פיגומים מהונדסים5,27,28,29. לאחרונה, מודלים גידול 3D נוצרו עם סוגי תאים מרובים מסודרים במבנים 3D בהתאמה שלהם. בדוגמה אחת של פלטפורמת גידול על שבב, סרטן, אנדותל, תאים סטרומה היו מעורבבים לתוך מטריצה ולאחר מכן מוזרק לתוך שלושת תאי הרקמה המרכזיים במכשיר polydimethylsiloxane (PDMS). תאי הרקמה היו גובלים בשני ערוצים חוץים שייצגו עורק ונוזל. לאחר 5-7 ימים של תרבות, תאי אנדותל יצרו רשת microvascular ותאי סרטן התפשטו כדי ליצור גידולים קטנים ליד כלי הדם. פלטפורמה זו שימשה אז כדי לסנן סמים ושילובי סמים30. פלטפורמות נוספות לגידול על שבב נוצרו כדי לחקור גרורות וסוגי סרטן עם גירויים מכניים ספציפיים (למשל, זן מכני בריאה)31,32. עם זאת, פלטפורמות אלה בדרך כלל אינן כוללות הן כלי דם וסרטן במבנים 3D בהתאמה שלהם.
Biofabrication מראה הבטחה גדולה בקידום 3D במודלים גידולים במבחנה כלי דם, שכן הוא מאפשר שליטה מרחבית הדוקה על מיקום התא. למרות הצמיחה של bioprinting בעשור האחרון, מחקרים מעטים להתמקד במיוחד על גידולים33,34. בדוגמה אחת, הדפסה תלת מימדית של תאי HeLa בהידרוגל ג'לטין/אלגינט/פיברינוגן שימשה ליצירת מודל סרטן צוואר הרחם במבחנה. תאים סרטניים הודפסו ביולוגית כתאים בודדים ולאחר מכן הורשו ליצור ספרואידים, אשר הראו קצב התפשטות גבוה יותר, ביטוי מטאלופרוטאינאז מטריצה מוגברת, ו chemoresistance גבוה יותר מאשר תאים בתרבות 2D35. במחקרים אלה, כמו רבים אחרים36,37, השעיות תאים מנותקים הודפסו ביולוגית, ולאחר מכן תרביות התא סופקו עם רמזים מכניים וביוכימיים הנדרשים כדי לאפשר לתאים ליצור מבנה 3D. עם זאת, הרכבה עצמית תאית עשויה להימשך ימים או שבועות, עשויה לדרוש רמזים סביבתיים מרחביים וטמפורליים מורכבים, או לא להתרחש כאשר שני סוגי תאים הם תרבית משותפת. לדוגמה, תאי אפיתל השד גרמו למוות תאי בתאי אנדותל בתרבית דו-ממדית, ותאי אפיתל שד מנותקים לא נוצרו כדוריות תלת-ממדיות כאשר הודפסו ביולוגית באלגינאט/ג'לטין הידרוג'ל38. אפיתל שד מנותק או תאים סרטניים יצרו ספרואידים בביוינקים מבוססי אלגינט רק כאשר נלכדו בתבניות PDMS עגולות. במקרים אחרים, spheroids נוצרו באמצעות טיפות מושעה בלוחות באר עגולים מצורף אולטרה נמוך ולאחר מכן מעורבב לתוך bioinks מבוסס אלגינט39,40.
כעת אנו מתארים שיטה חלופית 3D רקמה biomanufacturing בפרוטוקול זה. במקום לזרוע תאים מנותקים ולחכות שתאים אלה ייצרו את המבנים תלת-ממדיים, אנו מתארים כיצד ליצור ולהדפיס ביולוגית ספרואידים של גידולים תלת-ממדיים ברשת צינור כלי דם כדי ליצור מודל תרבות-שיתוף גידולים שניתן להשתמש בו כמעט מיד. ניתן לגדל ספרואידים של גידולים במבחנה או להפיקם מרקמות אנושיות (אורגנואידים). באופן דומה, צינורות כלי דם ניתן לגדל או יכול להיגזר שברים microvascular רקמת שומן. Bioinks יכול לנוע בין אלגינט פעיל ביולוגית כדי Matrigel פעיל מאוד ביולוגית41. מאז מודל זה 3D גידול שיתוף תרבות יכול להיווצר עם מגוון רחב של מבני תאים bioinks, זה יכול לשלב סוגי תאים מרובים, מטריצות חוץ תאיות, ומדרגי כימוקין15,42. בעוד בניסוח הנוכחי שלה, רשתות אנדותל לא ניתן לחדור, איטרציות עתידיות יכול לשלב שיטה זו עם microfluids או על שבב מערכות. הדפסה ביולוגית של ספירואידים אפיתל שד תלת מימדי על רשתות אנדותל מאפשרת ביופבריציה מהירה של מודלים של השד האנושי לבדיקות סמים ורפואה מדויקת מותאמת אישית27.

<table>
	<tbody>
		<tr>
			<td>37&#176;C incubator, 5% CO2 and 95% humidity</td>
			<td>Sanyo</td>
			<td>MCO-20AIC</td>
			<td>Cell incubation</td>
		</tr>
		<tr>
			<td>3D Bio printer</td>
			<td>custom-made</td>
			<td>None</td>
			<td>Used for bioprinting</td>
		</tr>
		<tr>
			<td>8-well chamber slides</td>
			<td>VWR, Radnor, PA</td>
			<td>53106-306</td>
			<td>for seeding spheroids</td>
		</tr>
		<tr>
			<td>25-gauge needle</td>
			<td>Sigma, St. Louis, MO</td>
			<td>Z192406-100EA</td>
			<td>bioprinting syringe needle</td>
		</tr>
		<tr>
			<td>Absolute ethanol (200 proof )</td>
			<td>Sigma, St.Louis, MO</td>
			<td>E7023-500ML</td>
			<td>reconsitution of media components</td>
		</tr>
		<tr>
			<td>Affinipure F(ab&#8242;)2 fragment goat anti-mouse IgG</td>
			<td>Jackson ImmunoResearch, West Grove, PA</td>
			<td>115006020</td>
			<td>secondary block - Immunofluorescence</td>
		</tr>
		<tr>
			<td>Alexa Fluor 488 (1:200)</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>A-11006</td>
			<td>Seconday antibody-Immunofluorescence</td>
		</tr>
		<tr>
			<td>Bovine insulin</td>
			<td>Sigma, St.Louis, MO</td>
			<td>I-035-0.5ML</td>
			<td>MCF10A Media additive</td>
		</tr>
		<tr>
			<td>Bovine serum albumin (BSA)</td>
			<td>Sigma, St.Louis, MO</td>
			<td>A2153-500G</td>
			<td>Blocking agent -Immunofluorescence</td>
		</tr>
		<tr>
			<td>Falcon 70 &#181;m Cell Strainer</td>
			<td>Corning, Corning, NY</td>
			<td>352350</td>
			<td>Remove large or clustered spheroids</td>
		</tr>
		<tr>
			<td>CellTracker&#8482; Red CMTPX Dye</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>C34552</td>
			<td>pre-stain for HUVEC tubes</td>
		</tr>
		<tr>
			<td>Compact Centrifuge</td>
			<td>Hermle- Labnet, Edison ,NJ</td>
			<td>Z206A</td>
			<td>For cell centrifugations</td>
		</tr>
		<tr>
			<td>Cholera Toxin</td>
			<td>Sigma, St.Louis, MO</td>
			<td>C8052-.5MG</td>
			<td>MCF10A Media additive</td>
		</tr>
		<tr>
			<td>Conical tubes 15 mL</td>
			<td>VWR, Radnor, PA</td>
			<td>62406-200</td>
			<td>Collecting and resuspending cells</td>
		</tr>
		<tr>
			<td>Countess II-FL Cell counter</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>AMQAF1000</td>
			<td>counting cells</td>
		</tr>
		<tr>
			<td>Glass pipettes (10 mL)</td>
			<td>VWR, Radnor, PA</td>
			<td>76184-746</td>
			<td>cell resuspension</td>
		</tr>
		<tr>
			<td>DMEM F:12</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>11320033</td>
			<td>MCF10A basal media</td>
		</tr>
		<tr>
			<td>DMEM 1X</td>
			<td>VWR, Radnor, PA</td>
			<td>10-014-CV</td>
			<td>MDA-MB-231 basal media</td>
		</tr>
		<tr>
			<td>Endothelial Basal Medium-2 (EBM-2)</td>
			<td>Lonza, Durham, NC</td>
			<td>CC-3156</td>
			<td>HUVEC basal media</td>
		</tr>
		<tr>
			<td>Endothelial Growth Medium-2 (EGM-2)</td>
			<td>Lonza, Durham, NC</td>
			<td>CC-3162</td>
			<td>Accompanied with a Bulletkit (containing growth factors)</td>
		</tr>
		<tr>
			<td>Alexa Fluor&#8482; 488 Phalloidin</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td></td>
			<td>Labelling MDA-MB-231 spheroids</td>
		</tr>
		<tr>
			<td>Fetal Bovine serum</td>
			<td>Cytiva, Logan, UT</td>
			<td>SH30071.03</td>
			<td>HUVEC/MDA-MB-231 media additive</td>
		</tr>
		<tr>
			<td>Goat serum</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>16210064</td>
			<td>Live and dead cell stain assay for cell viability</td>
		</tr>
		<tr>
			<td>Glycine</td>
			<td>Sigma, St.Louis, MO</td>
			<td>G8898-500G</td>
			<td>immunofluorescence buffer component</td>
		</tr>
		<tr>
			<td>Hoescht 33342</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>62249</td>
			<td>Nuclei stain immunofluorescence</td>
		</tr>
		<tr>
			<td>Horse Serum</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>16050130</td>
			<td>MCF10A Media additive</td>
		</tr>
		<tr>
			<td>Hydrocortisone</td>
			<td>Sigma, St.Louis, MO</td>
			<td>H0888-5G</td>
			<td>MCF10A Media additive</td>
		</tr>
		<tr>
			<td>Human Umblical Vein Endothelial cells (HUVECs)</td>
			<td>Cell applications, San Diego , CA</td>
			<td>200-05f</td>
			<td>Endothelial cell lines</td>
		</tr>
		<tr>
			<td>Integrin &#945;6</td>
			<td>Millipore, Billerica, MA</td>
			<td>MAB1378</td>
			<td>Immunofluorescence spheroid labelling component</td>
		</tr>
		<tr>
			<td>Live Dead assay</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>L3224</td>
			<td>Live and dead cell stain assay for cell viability</td>
		</tr>
		<tr>
			<td>LSM 700 Confocal microscope</td>
			<td>Zeiss, Thornwood, NY</td>
			<td></td>
			<td>Used to visualize cells</td>
		</tr>
		<tr>
			<td>Matrigel - growth factor reduced 10 mg/ml</td>
			<td>VWR, Radnor, PA</td>
			<td>354230</td>
			<td>Spheroid formation</td>
		</tr>
		<tr>
			<td>MCF10A cells</td>
			<td>ATCC</td>
			<td>CRL-10317</td>
			<td>Breast cell line</td>
		</tr>
		<tr>
			<td>MDA-MB-231 cells</td>
			<td>ATCC</td>
			<td>HTB-26</td>
			<td>Breast cell line</td>
		</tr>
		<tr>
			<td>Paraformaldehyde</td>
			<td>Sigma, St.Louis, MO</td>
			<td>158127-500G</td>
			<td>cell fixative</td>
		</tr>
		<tr>
			<td>Penicillin and streptomycin</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>15140122</td>
			<td>MCF10A / MDA-MB-231/HUVEC Media additive</td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline 1X (PBS)</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>7001106</td>
			<td>Wash buffer for cells before trypsinization</td>
		</tr>
		<tr>
			<td>Phosphate buffer saline 10X</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>AM9625</td>
			<td>immunofluorescence buffer component</td>
		</tr>
		<tr>
			<td>Prolong gold antifade</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>P36934</td>
			<td>immunofluorescence mountant medium</td>
		</tr>
		<tr>
			<td>Recombinant Human Epidermal Growth Factor, EGF</td>
			<td>Peprotech, Rocky Hill, NJ</td>
			<td>AF-100-15</td>
			<td>MCF10A/ assay media component</td>
		</tr>
		<tr>
			<td>Sodium Azide</td>
			<td>Sigma, St.Louis, MO</td>
			<td>S2002-25G</td>
			<td>immunofluorescence buffer component</td>
		</tr>
		<tr>
			<td>Sterile syringe (10 mL)</td>
			<td>VWR, Radnor, PA</td>
			<td>75846-757</td>
			<td>bioprinting process</td>
		</tr>
		<tr>
			<td>Tissue culture dish (10cm)</td>
			<td>VWR, Radnor, PA</td>
			<td>25382-166</td>
			<td>monolayer cell culture</td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>Sigma, St.Louis, MO</td>
			<td>T8787-250ML</td>
			<td>immunofluorescence buffer component</td>
		</tr>
		<tr>
			<td>Trypan blue 0.4%</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>15250061</td>
			<td>cell counter additive</td>
		</tr>
		<tr>
			<td>Trypsin-EDTA 0.05%</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>25300054</td>
			<td>cell detachment</td>
		</tr>
		<tr>
			<td>Tween -20</td>
			<td>Thermo Fisher, Waltham, MA</td>
			<td>85113</td>
			<td>immunofluorescence buffer component</td>
		</tr>
		<tr>
			<td>&#62;Vascular Endothelial Growth factor (VEGF165)</td>
			<td>Peprotech, Rocky Hill, NJ</td>
			<td>100-20</td>
			<td>HUVEC tube additive</td>
		</tr>
		<tr>
			<td>Volocity 6.3 cell imaging software</td>
			<td>PerkinElmer, Hopkinton, MA</td>
			<td></td>
			<td>Z stack compresser</td>
		</tr>
	</tbody>
</table>

direct bioprinting of 3d multicellular breast spheroids onto endothelial networks

Bioprinting מתגלה ככלי מבטיח לפברק מודלים של סרטן אנושי 3D כי טוב יותר לסכם סימני ההיכר הקריטיים של ארכיטקטורת רקמת vivo. בהדפסה ביולוגית של שחול שכבה אחר שכבה, תאים בודדים מובלטים בביו-ינק יחד עם רמזים מרחביים וטמפורליים מורכבים לקידום הרכבה עצמית של רקמות היררכיות. עם זאת, טכניקה זו biofabrication מסתמך על אינטראקציות מורכבות בין תאים, bioinks ורמזים ביוכימיים וביופיזיים. לכן, הרכבה עצמית עשויה להימשך ימים או אפילו שבועות, עשויה לדרוש bioinks ספציפי, ולא תמיד יכול להתרחש כאשר יש יותר מסוג תא אחד מעורב. לכן פיתחנו טכניקה להדפסה ביולוגית ישירה של ספירואידים אפיתל שד תלת-ממדיים שנוצרו מראש במגוון ביו-לינקים. ספירואידים אפיתל שד 3D מעוצבים מראש קיימו את הכדאיות שלהם ואת הארכיטקטורה המקוטבת לאחר ההדפסה. בנוסף הדפסנו את הכדורואידים בתלת-ממד על רשתות תאי אנדותל של כלי הדם כדי ליצור מודל של תרבות משותפת. לכן, טכניקת ההדפסה הביולוגית החדשה יוצרת במהירות מודל שד אנושי תלת מימדי רלוונטי יותר מבחינה פיזיולוגית בעלות נמוכה יותר ועם גמישות גבוהה יותר מאשר טכניקות הדפסה ביולוגית מסורתיות. טכניקת ביו-הדפסה רב-תכליתית זו ניתנת להדפסה כדי ליצור מודלים תלת-ממדיים של רקמות אחרות בביו-ינקים נוספים.

תאי אפיתל השד צריך להתארגן עצמית לתוך 3D spheroids לאחר 5-8 ימים של תרבות על פתרון מטריצה במדיום תרבות עם 2% פתרון מטריצה. כדורי אפיתל שאינם גידוליים של שד MCF10A צריכים להופיע עגולים ויש להם מרכז חלול, עם אינגרין α6 מקוטב לקצה החיצוני של הספרואיד(איור 1,inset מראה מרכזים חלולים). תאי אפית?...

Watch this Scientific Journal Video about Direct Bioprinting of 3D Multicellular Breast Spheroids onto Endothelial Networks at JoVE.com

Direct Bioprinting of 3D Multicellular Breast Spheroids onto Endothelial Networks

המטרה של פרוטוקול זה היא ישירות bioprint תאי אפיתל השד כמו כדוריות רב תאיות על רשתות אנדותל שנוצרו מראש כדי ליצור במהירות מודלים 3D השד אנדותל שיתוף תרבות אשר ניתן להשתמש בהם עבור מחקרים הקרנת סמים.

הדפסה ביולוגית ישירה של ספירואידי שד רב-תאיים תלת-תאיים ברשתות אנדותל

Bioprinting is emerging as a promising tool to fabricate 3D human cancer models that better recapitulate critical hallmarks of in vivo tissue ...

direct-bioprinting-3d-multicellular-breast-spheroids-onto-endothelial

Research

JoVE Journal

Bioengineering

4.8K Views.  Drexel University. המטרה של פרוטוקול זה היא ישירות bioprint תאי אפיתל השד כמו כדוריות רב תאיות על רשתות אנדותל שנוצרו מראש כדי ליצור במהירות מודלים 3D השד אנדותל שיתוף תרבות אשר ניתן להשתמש בהם עבור מחקרים הקרנת סמים.

Video: Direct Bioprinting of 3D Multicellular Breast Spheroids onto Endothelial Networks

A Simple Hanging Drop Cell Culture Protocol for Generation of 3D Spheroids

Studies of cell-cell cohesion and cell-substratum adhesion have historically been performed on monolayer cultures adherent to rigid substrates. Cells within a tissue, however, are typically encased within a closely packed tissue mass in which cells establish intimate connections with many near-neighbors and with extracellular matrix components. Accordingly, the chemical milieu and physical forces experienced by cells within a 3D tissue are fundamentally different than those experienced by cells grown in monolayer culture. This has been shown to markedly impact cellular morphology and signaling. Several methods have been devised to generate 3D cell cultures including encapsulation of cells in collagen gels1or in biomaterial scaffolds2. Such methods, while useful, do not recapitulate the intimate direct cell-cell adhesion architecture found in normal tissues. Rather, they more closely approximate culture systems in which single cells are loosely dispersed within a 3D meshwork of ECM products. Here, we describe a simple method in which cells are placed in hanging drop culture and incubated under physiological conditions until they form true 3D spheroids in which cells are in direct contact with each other and with extracellular matrix components. The method requires no specialized equipment and can be adapted to include addition of any biological agent in very small quantities that may be of interest in elucidating effects on cell-cell or cell-ECM interaction. The method can also be used to co-culture two (or more) different cell populations so as to elucidate the role of cell-cell or cell-ECM interactions in specifying spatial relationships between cells. Cell-cell cohesion and cell-ECM adhesion are the cornerstones of studies of embryonic development, tumor-stromal cell interaction in malignant invasion, wound healing, and for applications to tissue engineering. This simple method will provide a means of generating tissue-like cellular aggregates for measurement of biomechanical properties or for molecular and biochemical analysis in a physiologically relevant model.

We describe a simple, rapid method of generating 3D tissue-like spheroids and their potential application to quantify differences in cell-cell interactions.

תא פשוט תלוי תרבות Drop פרוטוקול הדור של Spheroids 3D

Studies of cell-cell cohesion and cell-substratum adhesion have historically been performed on monolayer cultures adherent to rigid substrates. Cells ...

Tissue Engineering: Construction of a Multicellular 3D Scaffold for the Delivery of Layered Cell Sheets

Many tissues, such as the adult human hearts, are unable to adequately regenerate after damage.2,3 Strategies in tissue engineering propose innovations to assist the body in recovery and repair. For example, TE approaches may be able to attenuate heart remodeling after myocardial infarction (MI) and possibly increase total heart function to a near normal pre-MI level.4 As with any functional tissue, successful regeneration of cardiac tissue involves the proper delivery of multiple cell types with environmental cues favoring integration and survival of the implanted cell/tissue graft. Engineered tissues should address multiple parameters including: soluble signals, cell-to-cell interactions, and matrix materials evaluated as delivery vehicles, their effects on cell survival, material strength, and facilitation of cell-to-tissue organization. Studies employing the direct injection of graft cells only ignore these essential elements.2,5,6 A tissue design combining these ingredients has yet to be developed. Here, we present an example of integrated designs using layering of patterned cell sheets with two distinct types of biological-derived materials containing the target organ cell type and endothelial cells for enhancing new vessels formation in the &#8220;tissue&#8221;. Although these studies focus on the generation of heart-like tissue, this tissue design can be applied to many organs other than heart with minimal design and material changes, and is meant to be an off-the-shelf product for regenerative therapies. The protocol contains five detailed steps. A temperature sensitive Poly(N-isopropylacrylamide) (pNIPAAM) is used to coat tissue culture dishes. Then, tissue specific cells are cultured on the surface of the coated plates/micropattern surfaces to form cell sheets with strong lateral adhesions. Thirdly, a base matrix is created for the tissue by combining porous matrix with neovascular permissive hydrogels and endothelial cells. Finally, the cell sheets are lifted from the pNIPAAM coated dishes and transferred to the base element, making the complete construct.

For creation of highly organized structures of complex tissue, one must assemble multiple material and cell types into an integrated composite. This combinatorial design incorporates organ-specific layered cell sheets with two distinct biologically-derived materials containing a strong fibrous matrix base, and endothelial cells for enhancing new vessels formation.

הנדסת רקמות: בנייה תאית 3D פיגום למשלוח גיליונות סלולריים שכבות

Many tissues, such as the adult human hearts, are unable to adequately regenerate after damage.2,3 Strategies in tissue engineering propose innovations to ...

Modeling Ovarian Cancer Multicellular Spheroid Behavior in a Dynamic 3D Peritoneal Microdevice

Ovarian cancer is characterized by extensive peritoneal metastasis, with tumor spheres commonly found in the malignant ascites. This is associated with poor clinical outcomes and currently lacks effective treatment. Both the three-dimensional (3D) environment and the dynamic mechanical forces are very important factors in this metastatic cascade. However, traditional cell cultures fail to recapitulate this natural tumor microenvironment. Thus, in vivo-like models that can emulate the intraperitoneal environment are of obvious importance. In this study, a new microfluidic platform of the peritoneum was set up to mimic the situation of ovarian cancer spheroids in the peritoneal cavity during metastasis. Ovarian cancer spheroids generated under a non-adherent condition were cultured in microfluidic channels coated with peritoneal mesothelial cells subjected to physiologically relevant shear stress. In summary, this dynamic 3D ovarian cancer-mesothelium microfluidic platform can provide new knowledge on basic cancer biology and serve as a platform for potential drug screening and development.

To study ovarian tumor progression in a physiologically relevant model, multicellular spheroids were cultured in a microdevice under simulated fluid flow. This dynamic 3D model emulates the intraperitoneal environment with the cellular and mechanical components where ovarian cancer metastasis occurs.

דוגמנות התנהגות אליפטית סרטן השחלות תאיים בתוך Microdevice הצפק 3D דינמי

Ovarian cancer is characterized by extensive peritoneal metastasis, with tumor spheres commonly found in the malignant ascites. This is associated with ...

Creation of Cardiac Tissue Exhibiting Mechanical Integration of Spheroids Using 3D Bioprinting

This protocol describes 3D bioprinting of cardiac tissue without the use of biomaterials, using only cells. Cardiomyocytes, endothelial cells and fibroblasts are first isolated, counted and mixed at desired cell ratios. They are co-cultured in individual wells in ultra-low attachment 96-well plates. Within 3 days, beating spheroids form. These spheroids are then picked up by a nozzle using vacuum suction and assembled on a needle array using a 3D bioprinter. The spheroids are then allowed to fuse on the needle array. Three days after 3D bioprinting, the spheroids are removed as an intact patch, which is already spontaneously beating. 3D bioprinted cardiac patches exhibit mechanical integration of component spheroids and are highly promising in cardiac tissue regeneration and as 3D models of heart disease.

This protocol describes 3D bioprinting of cardiac tissue without the use of biomaterials. 3D bioprinted cardiac patches exhibit mechanical integration of component spheroids and are highly promising in cardiac tissue regeneration and as 3D models of heart disease.

יצירת רקמת הלב מציגה שילוב מכני של Spheroids באמצעות 3D Bioprinting

This protocol describes 3D bioprinting of cardiac tissue without the use of biomaterials, using only cells. Cardiomyocytes, endothelial cells and ...

Bioprinting of Cartilage and Skin Tissue Analogs Utilizing a Novel Passive Mixing Unit Technique for Bioink Precellularization

Bioprinting is a powerful technique for the rapid and reproducible fabrication of constructs for tissue engineering applications. In this study, both cartilage and skin analogs were fabricated after bioink pre-cellularization utilizing a novel passive mixing unit technique. This technique was developed with the aim to simplify the steps involved in the mixing of a cell suspension into a highly viscous bioink. The resolution of filaments deposited through bioprinting necessitates the assurance of uniformity in cell distribution prior to printing to avoid the deposition of regions without cells or retention of large cell clumps that can clog the needle. We demonstrate the ability to rapidly blend a cell suspension with a bioink prior to bioprinting of both cartilage and skin analogs. Both tissue analogs could be cultured for up to 4 weeks. Histological analysis demonstrated both cell viability and deposition of tissue specific extracellular matrix (ECM) markers such as glycosaminoglycans (GAGs) and collagen I respectively.

Cartilage and skin analogs were bioprinted using a nanocellulose-alginate based bioink. The bioinks were cellularized prior to printing via a single step passive mixing unit. The constructs were demonstrated to be uniformly cellularized, have high viability, and exhibit favorable markers of differentiation.

Bioprinting של הסחוס, תחליפי רקמת העור ניצול פסיבים הרומן ערבוב טכניקה יחידה עבור Bioink Precellularization

Bioprinting is a powerful technique for the rapid and reproducible fabrication of constructs for tissue engineering applications. In this study, both ...

Lab-on-a-CD Platform for Generating Multicellular Three-dimensional Spheroids

A three-dimensional spheroid cell culture can obtain more useful results in cell experiments because it can better simulate cell microenvironments of the living body than two-dimensional cell culture. In this study, we fabricated an electrical motor-driven lab-on-a-CD (compact disc) platform, called a centrifugal microfluidic-based spheroid (CMS) culture system, to create three-dimensional (3D) cell spheroids implementing high centrifugal force. This device can vary rotation speeds to generate gravity conditions from 1 x g to 521 x g. The CMS system is 6 cm in diameter, has one hundred 400 &#956;m microwells, and is made by molding with polydimethylsiloxane in a polycarbonate mold premade by a computer numerical control machine. A barrier wall at the channel entrance of the CMS system uses centrifugal force to spread cells evenly inside the chip. At the end of the channel, there is a slide region that allows the cells to enter the microwells. As a demonstration, spheroids were generated by monoculture and coculture of human adipose-derived stem cells and human lung fibroblasts under high gravity conditions using the system. The CMS system used a simple operation scheme to produce coculture spheroids of various structures of concentric, Janus, and sandwich. The CMS system will be useful in cell biology and tissue engineering studies that require spheroids and organoid culture of single or multiple cell types.

We present a motor-powered centrifugal microfluidic device that can cultivate cell spheroids. Using this device, spheroids of single or multiple cell types could be easily cocultured under high gravity conditions.

פלטפורמת מעבדה-על-CD ליצירת רב-תאיים תלת מימדי

A three-dimensional spheroid cell culture can obtain more useful results in cell experiments because it can better simulate cell microenvironments of the ...

Protocols of 3D Bioprinting of Gelatin Methacryloyl Hydrogel Based Bioinks

Gelatin methacryloyl (GelMA) has become a popular biomaterial in the field of bioprinting. The derivation of this material is gelatin, which is hydrolyzed from mammal collagen. Thus, the arginine-glycine-aspartic acid (RGD) sequences and target motifs of matrix metalloproteinase (MMP) remain on the molecular chains, which help achieve cell attachment and degradation. Furthermore, formation properties of GelMA are versatile. The methacrylamide groups allow a material to become rapidly crosslinked under light irradiation in the presence of a photoinitiator. Therefore, it makes great sense to establish suitable methods for synthesizing three-dimensional (3D) structures with this promising material. However, its low viscosity restricts GelMA's printability. Presented here are methods to carry out 3D bioprinting of GelMA hydrogels, namely the fabrication of GelMA microspheres, GelMA fibers, GelMA complex structures, and GelMA-based microfluidic chips. The resulting structures and biocompatibility of the materials as well as the printing methods are discussed. It is believed that this protocol may serve as a bridge between previously applied biomaterials and GelMA as well as contribute to the establishment of GelMA-based 3D architectures for biomedical applications.

Presented here is a method for the 3D bioprinting of gelatin methacryloyl.

פרוטוקולים של 3D ביוריטינג ג'לטין הידרוג'ל מבוסס-דיו

Gelatin methacryloyl (GelMA) has become a popular biomaterial in the field of bioprinting. The derivation of this material is gelatin, which is hydrolyzed ...

3D Bioprinting of Murine Cortical Astrocytes for Engineering Neural-Like Tissue

Astrocytes are glial cells with an essential role in the central nervous system (CNS), including neuronal support and functionality. These cells also respond to neural injuries and act to protect the tissue from degenerative events. In vitro studies of astrocytes&#39; functionality are important to elucidate the mechanisms involved in such events and contribute to developing therapies to treat neurological disorders. This protocol describes a method to biofabricate a neural-like tissue structure rich in astrocytes by 3D bioprinting astrocytes-laden bioink. An extrusion-based 3D bioprinter was used in this work, and astrocytes were extracted from C57Bl/6 mice pups&#39; brain cortices. The bioink was prepared by mixing cortical astrocytes from up to passage 3 to a biomaterial solution composed of gelatin, gelatin-methacryloyl (GelMA), and fibrinogen, supplemented with laminin, which presented optimal bioprinting conditions. The 3D bioprinting conditions minimized cell stress, contributing to the high viability of the astrocytes during the process, in which 74.08% &#177; 1.33% of cells were viable right after bioprinting. After 1 week of incubation, the viability of astrocytes significantly increased to 83.54% &#177; 3.00%, indicating that the 3D construct represents a suitable microenvironment for cell growth. The biomaterial composition allowed cell attachment and stimulated astrocytic behavior, with cells expressing the specific astrocytes marker glial fibrillary acidic protein (GFAP) and possessing typical astrocytic morphology. This&#160;reproducible protocol provides a valuable method to biofabricate 3D neural-like tissue rich in astrocytes that resembles cells&#39; native microenvironment, useful to researchers that aim to understand astrocytes&#39; functionality and their relation to the mechanisms involved in neurological diseases.

Here we report a method of 3D bioprinting murine cortical astrocytes for biofabricating neural-like tissues to study the functionality of astrocytes in the central nervous system and the mechanisms involving glial cells in neurological diseases and treatments.

הדפסה ביולוגית תלת-ממדית של אסטרוציטים קליפת המוח מורין לרקמה דמוית עצב הנדסית

Astrocytes are glial cells with an essential role in the central nervous system (CNS), including neuronal support and functionality. These cells also ...

Affordable Oxygen Microscopy-Assisted Biofabrication of Multicellular Spheroids

Multicellular spheroids are important tools for studying tissue and cancer physiology in 3D and are frequently used in tissue engineering as tissue assembling units for biofabrication. While the main power of the spheroid model is in mimicking physical-chemical gradients at the tissue microscale, the real physiological environment (including dynamics of metabolic activity, oxygenation, cell death, and proliferation) inside the spheroids is generally ignored. At the same time, the effects of the growth medium composition and the formation method on the resulting spheroid phenotype are well documented. Thus, characterization and standardization of spheroid phenotype are required to ensure the reproducibility and transparency of the research results. The analysis of average spheroid oxygenation and the value of O2 gradients in three dimensions (3D) can be a simple and universal way for spheroid phenotype characterization, pointing at their metabolic activity, overall viability, and potential to recapitulate in vivo tissue microenvironment. The visualization of 3D oxygenation can be easily combined with multiparametric analysis of additional physiological parameters (such as cell death, proliferation, and cell composition) and applied for continuous oxygenation monitoring and/or end-point measurements. The loading of the O2 probe is performed during the stage of spheroid formation and is compatible with various protocols of spheroid generation. The protocol includes a high-throughput method of spheroid generation with introduced red and near-infrared emitting ratiometric fluorescent O2 nanosensors and the description of multi-parameter assessment of spheroid oxygenation and cell death before and after bioprinting. The experimental examples show comparative O2 gradients analysis in homo- and hetero-cellular spheroids as well as spheroid-based bioprinted constructs. The protocol is compatible with a conventional fluorescence microscope having multiple fluorescence filters and a light-emitting diode as a light source.

The protocol describes high-throughput spheroid generation for bioprinting using the multi-parametric analysis of their oxygenation and cell death on a standard fluorescence microscope. This approach can be applied to control the spheroids viability and perform standardization, which is important in modeling 3D tissue, tumor microenvironment, and successful (micro)tissue biofabrication.

מיקרופריקציה ביולוגית בסיוע מיקרוסקופיית חמצן במחיר סביר של ספרואידים רב-תאיים

Multicellular spheroids are important tools for studying tissue and cancer physiology in 3D and are frequently used in tissue engineering as tissue ...

Large-Scale, Automated Production of Adipose-Derived Stem Cell Spheroids for 3D Bioprinting

Adipose-derived stromal/stem cells (ASCs) are a subpopulation of cells found in the stromal vascular fraction of human subcutaneous adipose tissue recognized as a classical source of mesenchymal stromal/stem cells. Many studies have been published with ASCs for scaffold-based tissue engineering approaches, which mainly explored the behavior of these cells after their seeding on bioactive scaffolds. However, scaffold-free approaches are emerging to engineer tissues in vitro and in vivo, mainly by using spheroids, to overcome the limitations of scaffold-based approaches.
Spheroids are 3D microtissues formed by the self-assembly process. They can better mimic the architecture and microenvironment of native tissues, mainly due to the magnification of cell-to-cell and cell-to-extracellular matrix interactions. Recently, spheroids are mainly being explored as disease models, drug screening studies, and building blocks for 3D bioprinting. However, for 3D bioprinting approaches, numerous spheroids, homogeneous in size and shape, are necessary to biofabricate complex tissue and organ models. In addition, when spheroids are produced automatically, there is little chance for microbiological contamination, increasing the reproducibility of the method.
The large-scale production of spheroids is considered the first mandatory step for developing a biofabrication line, which continues in the 3D bioprinting process and finishes in the full maturation of the tissue construct in bioreactors. However, the number of studies that explored the large-scale ASC spheroid production are still scarce, together with the number of studies that used ASC spheroids as building blocks for 3D bioprinting. Therefore, this article aims to show the large-scale production of ASC spheroids using a non-adhesive micromolded hydrogel technique spreading ASC spheroids as building blocks for 3D bioprinting approaches.

Here, we describe the large-scale production of adipose-derived stromal/stem cell (ASC) spheroids using an automated pipetting system to seed the cell suspension, thus ensuring homogeneity of spheroid size and shape. These ASC spheroids can be used as building blocks for 3D bioprinting approaches.