This work was supported by NIH-NIDCR IRO1DE019355 (MJ Yost, PI), and NSF-EPSCoR (EPS-0903795).

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החוקרים אין לי מה לחשוף.

Biofabrication הוא שדה רב תחומית ביותר שבו עקרונות הביולוגיה וההנדסה למזג ליצור בחומרים מורכבים המחקות רקמות הילידים. כדי להשיג זאת, יש צורך לפתח טכניקות להשתמש במידע שנאסף רקמות in vivo ולתרגמו פיגום חוץ גופית. בדרך זו, פלטפורמה יכולה להיות מהונדסת דומה המאפיינים ה?...

בתחום הנדסת רקמות היכולת לפברק פיגומי רקמות היא חיונית. פיגום רקמות מתאים יש מבנה 3D, מורכב מחומרים ביולוגיים, ומחקתי באדריכלות רקמות vivo כדי להקל צמיחת תאים ורקמות שיפוץ. פיגום זה חייב לאפשר הובלה של חומרים מזינים ו הרחקת פסולת 1-4. אחד מכשולים העיקרי בייצור של פיגומים אלה הם היכולת לשחזר תכונות גיאומטריות ספציפיות לחומר ביולוגי. כמה טכניקות biofabrication דווחו לשלוט בתכונות הגיאומטריות של פיגומים אלו, דוגמאות הם electrospinning 5-8, ממס ליהוק 9, stereolithography 10, ו 3D-הדפסת 11, בין יתר. טכניקות אלו נופלים במתן העברה קל יחסית של מאפיינים אדריכליים פנימיים וחיצוניים לשליטה, הם יקרים, מוגבלים על ידי רזולוצית printability שלהם ( <em<html> &gt; למשל, מד זרבובית, הגבלת חומר), או לדרוש טכניקות שלאחר ייצור הדורש תקופה ארוכה של הזמן לייצר פיגומי קיימא 12. במערכות ייצור מסחריות רבות, יצירת חללים פנימיות, ערוצים, ותכונות מושגות באמצעות חול או חומרים נשלפים או הקרבה מתאימים אחרים. חלק המתכת או הפלסטיק נוצר סביב עובש החול, והפעם הוא הקרושה, בחול מוסר. ב הרבה באותו אופן, את הדור הבא של חומרים ביולוגיים צריך המקבילה biosand. לכן, גומי BSA פותח כתחליף biosand. גומי BSA הוא חומר שעוצבה זה מקרוב שמורכב אלבומין בסרום שור crosslinked עם glutaraldehyde. המטרה סופית הוא ליצור מחדש מאפיינים אדריכליים מסוימים לתוך פיגום קולגן מתכלה. המאפיינים של biorubber ההקרבה מקיימת נאמנות ממדים עם העובש של רקמה המקורית מתוארים. התחת = &quot;jove_content&quot;&gt; שילובים כמה ריכוזי BSA ו glutaraldehyde נבדקו באמצעות מגוון של ממיסים. חומר זה נוצר על ידי תגובה בין BSA ו glutaraldehyde. גומי BSA יכול להיות תגובה מוזרקת הגיאומטריות הסבוכות של תבניות רקמות. BSA Crosslinked הוא טריפסין יציב ולעכל בקלות על ידי האנזים בתנאי pH וטמפרטורה קל. לעומת זאת, סוג שלמים שאני קולגן הוא עמיד מאוד לעיכול טריפסין. תכונות אלו מהוונות להסיר את גומי BSA סלקטיבי עוזב את הקולגן מאחור. העבודה נוכחית כללה קביעת הפרמטרים האידיאליים צריכים להשיג עובש יציב שיכול לספק מאפיינים אדריכליים ספציפיים פיגום ביולוגי. התכונות הספציפיות אשר הוערכו כלל mixability, עיכול אנזים, נושאים עומס, ויכולת להיות תגובה מוזרקת לתוך תבנית שלילית. השילוב של BSA 30% ו -3% glutaraldehyde מילוי דרישות אלה. פרוטוקול זה מספק את necessהנחיות האר&quot;י ליצור פיגומים תלת ממדי אלה. אב הטיפוס כולל פיגום קולגן המייצג ארכיטקטורת קנים עם יבוא אחד ושני ערוצי זרימה בקטרים ​​של 4 ו 3 מ&quot;מ, בהתאמה. טכניקה זו יש פוטנציאל לחקות סביבות מיקרו מקרו של הרקמה של עניין. טכנולוגיה זו מספקת טכניקה מעשית לספק מאלפת גיאומטריות ספציפיות חומר מתכלה בתוך קל ומהיר יחסית עם איכות גבוהה, אשר יכול להיות מכוון לחקות את גמישות רקמות vivo ב ומאפיינים אחרים של הרקמה של עניין.

<table><tbody><tr><td>Collagen type I</td><td></td><td></td><td>Collagen extracted from calf hide</td></tr><tr><td>Hydrocloric Acid (HCl)</td><td>Sigma-Aldrich</td><td>7647-01-0</td><td></td></tr><tr><td>Phosphate Buffer Solution (PBS Tablets)</td><td>MP Biomedical</td><td>U5378</td><td>1 tablet per 100 ml makes 1x PBS</td></tr><tr><td>Albumium from bovine serum (BSA)</td><td>Sigma-Aldrich</td><td>A9647</td><td></td></tr><tr><td>Glutaraldehyde</td><td>Sigma -Aldrich</td><td>G5882</td><td>Toxic</td></tr><tr><td>Lard</td><td>Fields</td><td>3090</td><td></td></tr><tr><td>Stainless Steel Molds</td><td></td><td></td><td>Milled using Microlution Machine</td></tr><tr><td>Air Brush Kit</td><td>Central Pneumatic</td><td>47791</td><td></td></tr><tr><td>Mixing Tip for double syringe</td><td>Medmix</td><td>ML2.5-16-LLM</td><td>Mixer, DN2,5X16, 4:1 brown, med</td></tr><tr><td>Small O ring for double syringe</td><td>Medmix</td><td>PPB-X05-04-02SM</td><td>Piston B, 5 ml, 4:1, PE natural</td></tr><tr><td>Double Syringe cap&amp;nbsp;</td><td>Medmix</td><td>VLX002-SM</td><td>Cap, 4:1/10:1, PE brown, med</td></tr><tr><td>Big O ring for double syringe</td><td>Medmix</td><td>PPA-X05-04-02SM</td><td>Piston A, 5 ml, 4:1</td></tr><tr><td>Double Syringe</td><td>Medmix</td><td>SDL X05-04-50M</td><td>Double syringe, 5 ml, 4:1</td></tr><tr><td>Double Syringe Dispenser</td><td>Medmix</td><td>DL05-0400M</td><td>Dispenser, 5 ml, 4:1, med , plain</td></tr><tr><td>Laminim</td><td></td><td></td><td>3.6 mg/ml - extracted USC lab</td></tr><tr><td>20 ml Syringe Luer Lock Tip</td><td>BD</td><td>302830</td><td></td></tr><tr><td>Luer Lock Caps</td><td>Fisher</td><td>JGTCBLLX</td><td></td></tr><tr><td>HEPES</td><td>Sigma -Aldrich</td><td>H4034</td><td></td></tr><tr><td>Gibco Minimum Essential Media 10x (MEM)</td><td>Life Technologies</td><td>1143-030</td><td></td></tr><tr><td>Trypsin</td><td>Life Technologies</td><td>27250-018</td><td></td></tr><tr><td>UV Crosslinker&amp;nbsp;</td><td>Spectroline UV</td><td>XLE1000</td><td></td></tr><tr><td>Sodium Cloride (NaCl)</td><td>Fisher</td><td>S271-10</td><td>To prepare Mosconas</td></tr><tr><td>Potassium chloride (KCl)</td><td>Sigma -Aldrich</td><td>P5405-250</td><td>To prepare Mosconas</td></tr><tr><td>Sodium Bicarbonate (NaHCO&lt;sub&gt;3&lt;/sub&gt;)</td><td>Fisher</td><td>BP328-500</td><td>To prepare Mosconas</td></tr><tr><td>Glucose</td><td>Sigma -Aldrich</td><td>G-8270</td><td>To prepare Mosconas</td></tr><tr><td>Sodium Phosphate didasic (NaH&lt;sub&gt;2&lt;/sub&gt;PO&lt;sub&gt;4&lt;/sub&gt;)</td><td>Sigma-Aldrich</td><td>S-7907</td><td>To prepare Mosconas</td></tr><tr><td>Sterile Filter for syringes</td><td>Corning</td><td>431224</td><td></td></tr></tbody></table>

three-dimensional biomimetic technology: novel biorubber creates defined micro- and macro-scale architectures in collagen hydrogels

פיגומי רקמות לשחק תפקיד מכריע בתהליך התחדשות רקמות. הפיגום האידיאלי חייב למלא מספר דרישות כמו רכב ראוי שיש, מודולוס ממוקד, מאפיינים אדריכליים מוגדרים היטב. Biomaterials כי לשחזר את הארכיטקטורה הפנימית של רקמת in vivo הם חיוניים לחקר מחלות כמו גם כדי להקל על התחדשות של רקמות רכות איבד פגום. טכניקה biofabrication פותחה רומן המשלב מצב הדמיה אמנות, תלת ממדי (3D) הדפסה, ופעילות אנזימטית סלקטיבית כדי ליצור דור חדש של חומרים ביולוגיים למחקר ויישום קליני. החומר שפותח, גומי שור סרום אלבומין, הוא תגובה מוזרקת לתוך תבנית המקיימת תכונות גיאומטריות ספציפיות. חומר הקרבה זה מאפשר ההעברה הנאותה מאפיינים אדריכליים לחומר פיגום טבעי. אב הטיפוס כולל פיגום קולגן 3D עם ערוצי מ&quot;מ 4 ו -3 כי represent ארכיטקטורה מסועפת. מאמר זה מדגיש את השימוש בטכניקת biofabrication זה ההדור של מבנים טבעיים. פרוטוקול זה מנצל תוכנה בעזרת מחשב (CAD) לייצר תבנית מוצקה אשר תהיה תגובה הזריק גומי BSA ואחריו העיכול אנזימטי של הגומי, עוזב המאפיינים האדריכליים שלה בתוך חומר הפיגום.

התוצאות מראה כי טכניקת biofabrication זו יעילה ביצירת פיגומי 3D שיכולים לחקות את הסידור המרחבי לראות רקמות vivo. המאפיינים אדריכליים הם פרמטרים חיוניים עבור יישום הנדסת רקמות, החלו למלא תפקיד מרכזי ביחסי גומלין תא vivo ב והפונקציונלי של הרקמה. <p class...

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Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels

An innovative biofabrication technique was developed to engineer three-dimensional constructs that resemble the architectural features, components, and mechanical properties of in vivo tissue. This technique features a newly developed sacrificial material, BSA rubber, which transfers detailed spatial features, reproducing the in vivo architectures of a wide variety of tissues.

תלת ממדי טכנולוגיה Biomimetic: רומן Biorubber יוצר מוגדרת מיקרו מאקרו בקנה מידה ארכיטקטורות ב הידרוג קולגן

Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper ...

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Bioengineering

9.1K Views.  Medical University of South Carolina. An innovative biofabrication technique was developed to engineer three-dimensional constructs that resemble the architectural features, components, and mechanical properties of in vivo tissue. This technique features a newly developed sacrificial material, BSA rubber, which transfers detailed spatial features, reproducing the in vivo architectures of a wide variety of tissues.

Video: Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels

Fabrication of Micropatterned Hydrogels for Neural Culture Systems using Dynamic Mask Projection Photolithography

Increasingly, patterned cell culture environments are becoming a relevant technique to study cellular characteristics, and many researchers believe in the need for 3D environments to represent in vitro experiments which better mimic in vivo qualities 1-3. Studies in fields such as cancer research 4, neural engineering 5, cardiac physiology 6, and cell-matrix interaction7,8have shown cell behavior differs substantially between traditional monolayer cultures and 3D constructs.
Hydrogels are used as 3D environments because of their variety, versatility and ability to tailor molecular composition through functionalization 9-12. Numerous techniques exist for creation of constructs as cell-supportive matrices, including electrospinning13, elastomer stamps14, inkjet printing15, additive photopatterning16, static photomask projection-lithography17, and dynamic mask microstereolithography18. Unfortunately, these methods involve multiple production steps and/or equipment not readily adaptable to conventional cell and tissue culture methods. The technique employed in this protocol adapts the latter two methods, using a digital micromirror device (DMD) to create dynamic photomasks for crosslinking geometrically specific poly-(ethylene glycol) (PEG) hydrogels, induced through UV initiated free radical polymerization. The resulting "2.5D" structures provide a constrained 3D environment for neural growth. We employ a dual-hydrogel approach, where PEG serves as a cell-restrictive region supplying structure to an otherwise shapeless but cell-permissive self-assembling gel made from either Puramatrix or agarose. The process is a quick simple one step fabrication which is highly reproducible and easily adapted for use with conventional cell culture methods and substrates.
Whole tissue explants, such as embryonic dorsal root ganglia (DRG), can be incorporated into the dual hydrogel constructs for experimental assays such as neurite outgrowth. Additionally, dissociated cells can be encapsulated in the photocrosslinkable or self polymerizing hydrogel, or selectively adhered to the permeable support membrane using cell-restrictive photopatterning. Using the DMD, we created hydrogel constructs up to ~1mm thick, but thin film (&lt;200 &mu;m) PEG structures were limited by oxygen quenching of the free radical polymerization reaction. We subsequently developed a technique utilizing a layer of oil above the polymerization liquid which allowed thin PEG structure polymerization.
In this protocol, we describe the expeditious creation of 3D hydrogel systems for production of microfabricated neural cell and tissue cultures. The dual hydrogel constructs demonstrated herein represent versatile in vitro models that may prove useful for studies in neuroscience involving cell survival, migration, and/or neurite growth and guidance. Moreover, as the protocol can work for many types of hydrogels and cells, the potential applications are both varied and vast.

Simple techniques are described for the rapid production of microfabricated neural culture systems using a digital micromirror device for dynamic mask projection lithography on regular cell culture substrates. These culture systems may be more representative of natural biological architecture, and the techniques described could be adapted for numerous applications.

המצאה של הידרוג micropatterned למערכות התרבות עצבית באמצעות photolithography דינמי הקרנה מסכת

Increasingly, patterned cell culture environments are becoming a relevant technique to study cellular characteristics, and many researchers believe in the ...

Easy Manipulation of Architectures in Protein-based Hydrogels for Cell Culture Applications

Hydrogels are recognized as promising materials for cell culture applications due to their ability to provide highly hydrated cell environments. The field of 3D templates is rising due to the potential resemblance of those materials to the natural extracellular matrix. Protein-based hydrogels are particularly promising because they can easily be functionalized and can achieve defined structures with adjustable physicochemical properties. However, the production of macroporous 3D templates for cell culture applications using natural materials is often limited by their weaker mechanical properties compared to those of synthetic materials. Here, different methods were evaluated to produce macroporous bovine serum albumin (BSA)-based hydrogel systems, with adjustable pore sizes in the range of 10 to 70 &#181;m in radius. Furthermore, a method to generate channels in this protein-based material that are several hundred microns long was established. The different methods to produce pores, as well as the influence of pore size on material properties such as swelling ratio, pH, temperature stability, and enzymatic degradation behavior, were analyzed. Pore sizes were investigated in the native, swollen state of the hydrogels using confocal laser scanning microscopy. The feasibility for cell culture applications was evaluated using a cell-adhesive RGD peptide modification of the protein system and two model cell lines: human breast cancer cells (A549) and adenocarcinomic human alveolar basal epithelial cells (MCF7).

Different methods to manipulate three-dimensional architecture in protein-based hydrogels are evaluated here with respect to material properties. The macroporous networks are functionalized with a cell-adhesive peptide, and their feasibility in cell culture is evaluated using two different model cell lines.

טיפול קל של ארכיטקטורות ב Hydrogels חלבון מבוססת ליישומים תרבות תא

Hydrogels are recognized as promising materials for cell culture applications due to their ability to provide highly hydrated cell environments. The field ...

Biochemistry

Engineering 3D Cellularized Collagen Gels for Vascular Tissue Regeneration

Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. Collagen has been extensively used for a wide range of biomedical applications and is considered a valid alternative to synthetic materials due to its inherent biocompatibility (i.e., low antigenicity, inflammation, and cytotoxic responses). However, the limited mechanical properties and the related low hand-ability of collagen gels have hampered their use as scaffold materials for vascular tissue engineering. Therefore, the rationale behind this work was first to engineer cellularized collagen gels into a tubular-shaped geometry and second to enhance smooth muscle cells driven reorganization of collagen matrix to obtain tissues stiff enough to be handled.
The strategy described here is based on the direct assembling of collagen and smooth muscle cells (construct) in a 3D cylindrical geometry with the use of a molding technique. This process requires a maturation period, during which the constructs are cultured in a bioreactor under static conditions (without applied external dynamic mechanical constraints) for 1 or 2 weeks. The &#8220;static bioreactor&#8221; provides a monitored and controlled sterile environment (pH, temperature, gas exchange, nutrient supply and waste removal) to the constructs. During culture period, thickness measurements were performed to evaluate the cells-driven remodeling of the collagen matrix, and glucose consumption and lactate production rates were measured to monitor the cells metabolic activity. Finally, mechanical and viscoelastic properties were assessed for the resulting tubular constructs. To this end, specific protocols and a focused know-how (manipulation, gripping, working in hydrated environment, and so on) were developed to characterize the engineered tissues.

In this work, we present a technique for the rapid fabrication of living vascular tissues by direct culturing of collagen, smooth muscle cells and endothelial cells. In addition, a new protocol for the mechanical characterization of engineered vascular tissues is described.

הנדסת ג&#39;ל קולגן Cellularized 3D לשחזור רקמות וכלי דם

Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. ...

Layer-by-layer Collagen Deposition in Microfluidic Devices for Microtissue Stabilization

Although microfluidics provides exquisite control of the cellular microenvironment, culturing cells within microfluidic devices can be challenging. 3D culture of cells in collagen type I gels helps to stabilize cell morphology and function, which is necessary for creating microfluidic tissue models in microdevices. Translating traditional 3D culture techniques for tissue culture plates to microfluidic devices is often difficult because of the limited channel dimensions. In this method, we describe a technique for modifying native type I collagen to generate polycationic and polyanionic collagen solutions that can be used with layer-by-layer deposition to create ultrathin collagen assemblies on top of cells cultured in microfluidic devices. These thin collagen layers stabilize cell morphology and function, as shown using primary hepatocytes as an example cell, allowing for the long term culture of microtissues in microfluidic devices.

The creation of functional microtissues within microfluidic devices requires the stabilization of cell phenotypes by adapting traditional cell culture techniques to the limited spatial dimensions in microdevices. Modification of collagen allows the layer-by-layer deposition of ultrathin collagen assemblies that can stabilize primary cells, such as hepatocytes, as microfluidic tissue models.

קולגן שכבת הפקדת-ידי שכבה במכשירי microfluidic לMicrotissue ייצוב

Although microfluidics provides exquisite control of the cellular microenvironment, culturing cells within microfluidic devices can be challenging. 3D ...

Construction of Modular Hydrogel Sheets for Micropatterned Macro-scaled 3D Cellular Architecture

Hydrogels can be patterned at the micro-scale using microfluidic or micropatterning technologies to provide an in vivo-like three-dimensional (3D) tissue geometry. The resulting 3D hydrogel-based cellular constructs have been introduced as an alternative to animal experiments for advanced biological studies, pharmacological assays and organ transplant applications. Although hydrogel-based particles and fibers can be easily fabricated, it is difficult to manipulate them for tissue reconstruction. In this video, we describe a fabrication method for micropatterned alginate hydrogel sheets, together with their assembly to form a macro-scale 3D cell culture system with a controlled cellular microenvironment. Using a mist form of the calcium gelling agent, thin hydrogel sheets are easily generated with a thickness in the range of 100 - 200 &#181;m, and with precise micropatterns. Cells can then be cultured with the geometric guidance of the hydrogel sheets in freestanding conditions. Furthermore, the hydrogel sheets can be readily manipulated using a micropipette with an end-cut tip, and can be assembled into multi-layered structures by stacking them using a patterned polydimethylsiloxane (PDMS) frame. These modular hydrogel sheets, which can be fabricated using a facile process, have potential applications of in vitro drug assays and biological studies, including functional studies of micro- and macrostructure and tissue reconstruction.

We describe the fabrication of micropatterned hydrogel sheets using a simple process, which can be assembled and manipulated in a freestanding form. Using these modular hydrogel sheets, a simple macro-scaled 3D cell culture system can be generated with a controlled cellular microenvironment.

בנייה של גיליונות מודולרי Hydrogel לאדריכלות סלולרית 3D המוקטן מאקרו micropatterned

Hydrogels can be patterned at the micro-scale using microfluidic or micropatterning technologies to provide an in vivo-like three-dimensional (3D) tissue ...

Preparation of 3D Collagen Gels and Microchannels for the Study of 3D Interactions In Vivo

Historically, most cellular processes have been studied in only 2 dimensions. While these studies have been informative about general cell signaling mechanisms, they neglect important cellular cues received from the structural and mechanical properties of the local microenvironment and extracellular matrix (ECM). To understand how cells interact within a physiological ECM, it is important to study them in the context of 3 dimensional assays. Cell migration, cell differentiation, and cell proliferation are only a few processes that have been shown to be impacted by local changes in the mechanical properties of a 3-dimensional ECM. Collagen I, a core fibrillar component of the ECM, is more than a simple structural element of a tissue. Under normal conditions, mechanical cues from the collagen network direct morphogenesis and maintain cellular structures. In diseased microenvironments, such as the tumor microenvironment, the collagen network is often dramatically remodeled, demonstrating altered composition, enhanced deposition and altered fiber organization. In breast cancer, the degree of fiber alignment is important, as an increase in aligned fibers perpendicular to the tumor boundary has been correlated to poorer patient prognosis1. Aligned collagen matrices result in increased dissemination of tumor cells via persistent migration2,3. The following is a simple protocol for embedding cells within a 3-dimensional, fibrillar collagen hydrogel. This protocol is readily adaptable to many platforms, and can reproducibly generate both aligned and random collagen matrices for investigation of cell migration, cell division, and other cellular processes in a tunable, 3-dimensional, physiological microenvironment.

Preparation of 3D Collagen Gels and Microchannels for the Study of 3D Interactions In Vivo

Collagen is a core component of the ECM, and provides essential cues for several cellular processes ranging from migration to differentiation and proliferation. Provided here is a protocol for embedding cells within 3D collagen hydrogels, and a more advanced technique for generating randomized or aligned collagen matrices using PDMS microchannels.

הכנת ג&#39;לי 3D קולגן microchannels לחקר אינטראקציות 3D<em&gt; In vivo</em

Historically, most cellular processes have been studied in only 2 dimensions.  While these studies have been informative about general cell signaling ...

3D Microtissues for Injectable Regenerative Therapy and High-throughput Drug Screening

To upgrade traditional 2D cell culture to 3D cell culture, we have integrated microfabrication with cryogelation technology to produce macroporous microscale cryogels (microcryogels), which can be loaded with a variety of cell types to form 3D microtissues. Herein, we present the protocol to fabricate versatile 3D microtissues and their applications in regenerative therapy and drug screening. Size and shape-controllable microcryogels can be fabricated on an array chip, which can be harvested off-chip as individual cell-loaded carriers for injectable regenerative therapy or be further assembled on-chip into 3D microtissue arrays for high-throughput drug screening. Due to the high elastic nature of these microscale cryogels, the 3D microtissues exhibit great injectability for minimally invasive cell therapy by protecting cells from mechanical shear force during injection. This ensures enhanced cell survival and therapeutic effect in the mouse limb ischemia model. Meanwhile, assembly of 3D microtissue arrays in a standard 384-multi-well format facilitates the use of common laboratory facilities and equipment, enabling high-throughput drug screening on this versatile 3D cell culture platform.

This protocol describes the fabrication of elastic 3D macroporous microcryogels by integrating microfabrication with cryogelation technology. Upon loading with cells, 3D microtissues are generated, which can be readily injected in vivo to facilitate regenerative therapy or assembled into arrays for in vitro high-throughput drug screening.

Microtissues תלת-ממד עבור טיפול בזריקות רגנרטיבית ותפוקה גבוהה והתרופות הקרנה

To upgrade traditional 2D cell culture to 3D cell culture, we have integrated microfabrication with cryogelation technology to produce macroporous ...

Interlinked Macroporous 3D Scaffolds from Microgel Rods

A two-component system of functionalized microgels from microfluidics allows for fast interlinking into 3D macroporous constructs in aqueous solutions without further additives. Continuous photoinitiated on-chip gelation enables variation of the microgel aspect ratio, which determines the building block properties for the obtained constructs. Glycidyl methacrylate (GMA) or 2-aminoethyl methacrylate (AMA) monomers are copolymerized into the microgel network based on polyethylene glycol (PEG) star-polymers to achieve either epoxy or amine functionality. A focusing oil flow is introduced into the microfluidic outlet structure to ensure continuous collection of the functionalized microgel rods. Based on a recent publication, microgel rod-based constructs result in larger pores of several hundred micrometers and, at the same time, lead to overall higher scaffold stability in comparison to a spherical-based model. In this way, it is possible to produce higher-volume constructs with more free volume while reducing the amount of material required. The interlinked macroporous scaffolds can be picked up and transported without damage or disintegration. Amine and epoxy groups not involved in interlinking remain active and can be used independently for post-modification. This protocol describes an optimized method for the fabrication of microgel rods to form macroporous interlinked scaffolds that can be utilized for subsequent cell experiments.

Microgel rods with complementary reactive groups are produced via microfluidics with the ability to interlink in aqueous solution. The anisometric microgels jam and interlink into stable constructs with larger pores compared to spherical-based systems. Microgels modified with GRGDS-PC form macroporous 3D constructs that can be used for cell culture.

פיגומים תלת-ממדיים מקרו-נקבוביים משולבים ממוטות מיקרוג'ל

A two-component system of functionalized microgels from microfluidics allows for fast interlinking into 3D macroporous constructs in aqueous solutions ...

Microengineering 3D Collagen Hydrogels with Long-Range Fiber Alignment

Aligned collagen I (COL1) fibers guide tumor cell motility, influence endothelial cell morphology, control stem cell differentiation, and are a hallmark of cardiac and musculoskeletal tissues. To study cell response to aligned microenvironments in vitro, several protocols have been developed to generate COL1 matrices with defined fiber alignment, including magnetic, mechanical, cell-based, and microfluidic methods. Of these, microfluidic approaches offer advanced capabilities such as accurate control over fluid flows and the cellular microenvironment. However, the microfluidic approaches to generate aligned COL1 matrices for advanced in vitro culture platforms have been limited to thin "mats" (&lt;40 &#181;m in thickness) of COL1 fibers that extend over distances less than 500 &#181;m and are not conducive to 3D cell culture applications. Here, we present a protocol to fabricate 3D COL1 matrices (130-250 &#181;m in thickness) with millimeter-scale regions of defined fiber alignment in a microfluidic device. This platform provides advanced cell culture capabilities to model structured tissue microenvironments by providing direct access to the micro-engineered matrix for cell culture.

This protocol demonstrates the use of a microfluidic channel with changing geometry along the fluid flow direction to generate extensional strain (stretching) to align fibers in a 3D collagen hydrogel (&lt;250 &#181;m in thickness). The resulting alignment extends across several millimeters and is influenced by the extensional strain rate.

מיקרו-הנדסה הידרוג'ל קולגן תלת-ממדית עם יישור סיבים לטווח ארוך

Aligned collagen I (COL1) fibers guide tumor cell motility, influence endothelial cell morphology, control stem cell differentiation, and are a hallmark ...

Fabricating Engineered Nanofibrillar Collagen with Directed Patterning

Production of Nanofibrillar Patterned Collagen for Tissue Engineering

Regenerative biomaterials are designed to facilitate cell-material interactions to guide the repair of damaged tissues and organs. These materials are designed to emulate the biophysical properties of native tissue, providing cellular phenotypic and morphological guidance that contributes to the restoration of the regenerative tissue niche. Collagen, a prevalent extracellular matrix protein, is a common component of these regenerative biomaterials due to its biocompatibility and other favorable properties. The current study describes a novel and straightforward method for the fabrication of engineered nanofibrillar collagen with directed fibril patterning. Through the manipulation of shear stress, temperature, and pH, collagen fibrillogenesis and alignment are precisely controlled without requiring specialized equipment. This approach allows for the creation of nanofibrillar collagen biomaterials that mimic the native structure of tissues exhibiting either anisotropic or isotropic characteristics. The flexibility in collagen nanofibril patterning not only facilitates the study of nanoscale patterning on cell behavior but also offers diverse possibilities for patterned tissue engineering applications.

The following protocol presents a shear-based extrusion method for the fabrication of collagen hydrogels with nanoscale patterned fibrils, which can be applied to a broad range of tissue engineering applications.

Regenerative biomaterials are designed to facilitate cell-material interactions to guide the repair of damaged tissues and organs. These materials are ...

תלת ממדי טכנולוגיה Biomimetic: רומן Biorubber יוצר מוגדרת מיקרו מאקרו בקנה מידה ארכיטקטורות ב הידרוג קולגן

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