עבודה זו נתמכה על ידי מארי קירי הבינלאומי שילוב מחדש מענק.

<ol>
	<li>Maerkl, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integration+column:+Microfluidic+high-throughput+screening.">Integration column: Microfluidic high-throughput screening.</a> Integrative biology quantitative biosciences from nano to macro. 1, 19-29 (2009).</li><li>Hong, J. W., Quake, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrated+nanoliter+systems.">Integrated nanoliter systems.</a> Nature. 21, 1179-1183 (2003).</li><li>Unger, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Monolithic+Microfabricated+Valves+and+Pumps+by+Multilayer+Soft+Lithography.">A Monolithic Microfabricated Valves and Pumps by Multilayer Soft Lithography.</a> Science. 288, 113-116 (2000).</li><li>Gerber, D., Maerkl, S. J., Quake, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+in+vitro+microfluidic+approach+to+generating+protein-interaction+networks.">An in vitro microfluidic approach to generating protein-interaction networks.</a> Nature. 6, 71-74 (2009).</li><li>Einav, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Discovery+of+a+hepatitis+C+target+and+its+pharmacological+inhibitors+by+microfluidic+affinity+analysis.">Discovery of a hepatitis C target and its pharmacological inhibitors by microfluidic affinity analysis.</a> Nature. 26, 1019-1027 (2008).</li><li>Fordyce, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=De+novo+identification+and+biophysical+characterization+of+transcription-factor+binding+sites+with+microfluidic+affinity+analysis.">De novo identification and biophysical characterization of transcription-factor binding sites with microfluidic affinity analysis.</a> Nature Biotechnology. 28, 962-967 (2010).</li><li>Zhu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+analysis+of+protein+activities+using+proteome+chips.">Global analysis of protein activities using proteome chips.</a> Science (New York, N.Y.). 293, 2101-2105 (2001).</li><li>Ramachandran, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-assembling+protein+microarrays.">Self-assembling protein microarrays.</a> Science (New York, N.Y.). 305, 86-90 (2004).</li><li>Zhong, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+microfluidic+processor+for+gene+expression+profiling+of+single+human+embryonic+stem+cells.">A microfluidic processor for gene expression profiling of single human embryonic stem cells.</a> Lab on a chip. 8, 68-74 (2008).</li><li>Kusnezow, W., Hoheisel, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solid+supports+for+microarray+immunoassays.">Solid supports for microarray immunoassays.</a> Journal of molecular recognition JMR. 16, 165-176 (2003).</li><li>Lundin, M., Monne, M., Widell, A., Von Heijne, G., Persson, M. A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Topology+of+the+membrane-associated+hepatitis+C+virus+protein+NS4B.">Topology of the membrane-associated hepatitis C virus protein NS4B.</a> Journal of virology. 77, 5428 (2003).</li></ol>

אין ניגודי האינטרסים הכריזו.

במאמר זה אנו מציגים שיטה למערכי חלבון דור בתפוקה גבוהה באמצעות פלטפורמת microfluidic. דור המערך מתבסס על הדפסת microarray של DNA ותבניות ביטוי חלבון במבחנה מהדנ&quot;א בתוך מכשיר microfluidic. פלטפורמת microfluidic הרומן שלנו יש כמה יתרונות חשובים על פני שיטות המשמשות כיום, ההופכים אותו לכלי מבטיח וכללי לפרוטאומיקה. יתרון אחד הוא עם חלבוני קרום בכריכה. סינתזת חלבון במבחנה באמצעות lysates reticulocyte יונקים בנוכחות של קרומי microsomal 11 מספק &quot;טבעי כמו&quot; תנאים דרושים לחלבונים בממברנה. יתר על כן, מיקרופלואידיקה מאפשרת ביטוי חלבונים בכמויות נמוכות מאוד וטיהור חלבון אינה הכרחית. אלה הם צווארי הבקבוק השכיחים ביותר במתודולוגיות מקובלות. למעשה, אופטימיזציה נוספת של חלבונים יכולה להיות מושגת על ידי התאמה במבחנת cellysate l לחלבונים, למשל E. coli lysate לחלבונים חיידקיים. מיקרופלואידיקה מאפשרת ביטוי חלבונים בנפח קטן מאוד. בדוגמא הספציפית שלנו נפח התא הוא 1 nl. ישנם שני יתרונות לכמויות הנמוכות. הברור האחד הוא צריכה נמוכה יותר של חומרים כימיים והיכולת לעבוד עם חומרים נדירים (כלומר חלבונים בממברנה). יתרון משמעותי נוסף הוא שריכוז חלבונים על פני השטח עם נוגדנים בכמות כה קטנה מאפשר לנו להשיג את ריכוזים גבוהים יחסית של חלבונים עבור מבחני אינטראקציה, מה שיגביר את רגישות הבדיקה. את שסתומי לחצן יש תפקיד כפול. ראשית הם משמשים עבור דפוסי נוגדן תחת הכפתור בכל חדר. זה מאפשר לנו למשוך למטה את החלבונים רק בכפתורים, והשאר של חדר פסיבציה. שנית, הכפתורים לאפשר לשטיפה מכאנית ולכידה של חלבונים על ידי עקירת נפח של נוזלמתחת כאשר actuated. כביסה והשמנה זה מגדיל את הרגישות הכוללת של הפלטפורמה, ומאפשר זיהוי של אינטראקציות חלשות וחולפות מולקולריות 4. לבסוף, מכשיר microfluidic יכול בקלות להיות אוטומטי והוא מסוגל לבצע מדידות מקבילות רבות. ובכך לחסוך בעלויות, כמו גם בזמן. ההערכה שלנו היא שהעלות לניסוי חלבון באמצעות PING היא כ 2 סנאטים לחלבון, עם מכשירים נוכחיים הנעים עד 10,000 ניסויים למכשיר 4. הערכה זו כוללת ייצור וחומרים. לפיכך, PING יש את הפוטנציאל להיות כלי חזק למערך חלבון באופן כללי עם יתרונות ספציפיים כגון לחלבונים בממברנה.

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><td> מגיב / ציוד </td><td> חברה </td><td> מספר קטלוגים </td></tr><tr><td> PDMS-SYLGARD 184 </td><td> Dow Corning ארה&quot;ב </td><td> תסקס-DC </td></tr><tr><td> Chlorotrimethylsilane (TMCS </td><td> סיגמה אולדריץ </td><td> C72854 </td></tr><tr><td> מצעי זכוכית מצופי אפוקסי </td><td> CEL Associates ארה&quot;ב </td><td> VEPO-25C </td></tr><tr><td> פולי אתילן glycole (PEG) </td><td> סיגמה אולדריץ </td><td> 81260 </td></tr><tr><td> dihydrate D-הטרהלוז </td><td> סיגמה אולדריץ </td><td> T9531 </td></tr><tr><td> Biotinylated-BSA </td><td> לנקב </td><td> PIR-29130 </td></tr><tr><td> Neutravidin </td><td> לנקב </td><td> 31050 </td></tr><tr><td> מחומש-ביוטין </td><td> Qiagen </td&gt; <td> 34440 </td></tr><tr><td> Hepes </td><td> <a href="http://www.bioind.com/htmls/article.aspx?c0=741&amp;bsp=13384" target="_blank">תעשיות ביולוגיות</a> </td><td> 03-025-1B </td></tr><tr><td> TNT-T7 </td><td> Promega </td><td> L5540 </td></tr><tr><td> נוגדן הגן c-myc Cy3 </td><td> סיגמה אולדריץ </td><td></td></tr><tr><td> תיבת בקרה </td><td> סטנפורד מיקרופלואידיקה יציקה </td><td></td></tr><tr><td> עובש </td><td> סטנפורד מיקרופלואידיקה יציקה </td><td></td></tr><tr><td> פין </td><td> ניו אינגלנד קטנה צינורות תאגיד </td><td></td></tr><tr><td> צינורות Tygon microbore </td><td> Tygon </td><td> S-54-HL </td></tr><tr><td> Microarrayer </td><td> ביו רובוטיקה </td><td> MicroGrid 610 </td></tr><tr><td> סיכות סיליקון </td><td> במקביל Synתזה </td><td> SMT-S75 </td></tr></tbody></table>

high-throughput protein expression generator using a microfluidic platform

שדות בקצב מואץ, כגון ביולוגיה של מערכות, דורשים פיתוח והיישום של טכנולוגיות חדשות, המאפשרים מדידות גבוהות תפוקה ואיכות גבוהה של מערכות גדולות. מיקרופלואידיקה מבטיחה למלא רבים מהדרישות הללו, כגון ביצוע ניסויי תפוקה גבוהה הקרנה על שבב, הכוללת מבחנים ביוכימיים, biophysical, ומבוססי תאים 1. מאז הימים הראשונים של מכשירים מיקרופלואידיקה, תחום זה התפתח באופן דרסטי, שהוביל לפיתוח של אינטגרצית microfluidic בקנה מידה גדולה 2,3. טכנולוגיה זו מאפשרת לאינטגרציה של אלף שסתומי micromechanical במכשיר אחד עם טביעת רגל דואר בגודל (איור 1). פתחנו פלטפורמת microfluidic תפוקה גבוהה להפקה בביטוי מבחנה של מערכי חלבון (איור 2) בשם PING (גנרטור רשת אינטראקצית חלבון). מערכים אלה יכולים לשמש כתבנית לניסויים רביםכגון בין החלבונים 4, 5 חלבונים RNA או חלבון דנ&quot;א 6 אינטראקציות. המכשיר מורכב מאלף תאי תגובה, אשר תוכנתו בנפרד באמצעות microarrayer. יישור של microarrays המודפס אלה לתוכניות מיקרופלואידיקה התקנים כל תא עם נקודה בודדה שמבטלת אפשרות של זיהום או תגובה צולבת יתר על כן, יצירת microarrays באמצעות טכניקות תיכונה microarray הרגילות הוא גם מאוד מודולרי, המאפשר לarraying של חלבונים 7, 8 DNA, מולקולות קטנות, ואפילו השעיות colloidal. ההשפעה הפוטנציאלית של מיקרופלואידיקה במדעים ביולוגיים היא משמעותית. מספר מיקרופלואידיקה מבחנים מבוססים כבר ספק תובנה חדשות למבנה והתפקוד של מערכות ביולוגיות, ותחום מיקרופלואידיקה ימשיך להשפיע ביולוגיה.

Watch this Scientific Journal Video about High-throughput Protein Expression Generator Using a Microfluidic Platform at JoVE.com

High-throughput Protein Expression Generator Using a Microfluidic Platform

אנו מציגים גישת microfluidic לביטוי של מערכי חלבון. המכשיר מורכב מאלף תאי תגובה הנשלטים על ידי מייקרו שסתומים מכאניים. מכשיר microfluidic הוא הזדווגו לספריית גן microarray-מודפסת. גנים אלו אז מתועתקים ומתורגמים על שבב, וכתוצאה מכך מערך חלבון מוכן לשימוש ניסיוני.

גנרטור ביטוי חלבון תפוקה גבוהה באמצעות פלטפורמת Microfluidic

Rapidly increasing fields, such as systems biology, require the development and implementation of new technologies, enabling high-throughput and ...

high-throughput-protein-expression-generator-using-microfluidic

Nanyang Technological University

Research

JoVE Journal

Bioengineering

11.6K Views.  Bar-Ilan University. אנו מציגים גישת microfluidic לביטוי של מערכי חלבון. המכשיר מורכב מאלף תאי תגובה הנשלטים על ידי מייקרו שסתומים מכאניים. מכשיר microfluidic הוא הזדווגו לספריית גן microarray-מודפסת. גנים אלו אז מתועתקים ומתורגמים על שבב, וכתוצאה מכך מערך חלבון מוכן לשימוש ניסיוני.

Video: High-throughput Protein Expression Generator Using a Microfluidic Platform

Microfluidic Mixers for Studying Protein Folding

The process by which a protein folds into its native conformation is highly relevant to biology and human health yet still poorly understood. One reason for this is that folding takes place over a wide range of timescales, from nanoseconds to seconds or longer, depending on the protein1. Conventional stopped-flow mixers have allowed measurement of folding kinetics starting at about 1 ms. We have recently developed a microfluidic mixer that dilutes denaturant ~100-fold in ~8 &mu;s2. Unlike a stopped-flow mixer, this mixer operates in the laminar flow regime in which turbulence does not occur. The absence of turbulence allows precise numeric simulation of all flows within the mixer with excellent agreement to experiment3-4.
Laminar flow is achieved for Reynolds numbers Re &le;100. For aqueous solutions, this requires micron scale geometries. We use a hard substrate, such as silicon or fused silica, to make channels 5-10 &mu;m wide and 10 &mu;m deep (See Figure 1). The smallest dimensions, at the entrance to the mixing region, are on the order of 1 &mu;m in size. The chip is sealed with a thin glass or fused silica coverslip for optical access. Typical total linear flow rates are ~1 m/s, yielding Re~10, but the protein consumption is only ~0.5 nL/s or 1.8 &mu;L/hr. Protein concentration depends on the detection method: For tryptophan fluorescence the typical concentration is 100 &mu;M (for 1 Trp/protein) and for FRET the typical concentration is ~100 nM.
The folding process is initiated by rapid dilution of denaturant from 6 M to 0.06 M guanidine hydrochloride. The protein in high denaturant flows down a central channel and is met on either side at the mixing region by buffer without denaturant moving ~100 times faster (see Figure 2). This geometry causes rapid constriction of the protein flow into a narrow jet ~100 nm wide. Diffusion of the light denaturant molecules is very rapid, while diffusion of the heavy protein molecules is much slower, diffusing less than 1 &mu;m in 1 ms. The difference in diffusion constant of the denaturant and the protein results in rapid dilution of the denaturant from the protein stream, reducing the effective concentration of the denaturant around the protein. The protein jet flows at a constant rate down the observation channel and fluorescence of the protein during folding can be observed using a scanning confocal microscope5.

In this work we explain the fabrication and use of a microfluidic mixer capable of mixing two solutions in ~8 &mu;s. We also demonstrate the use of these mixers with spectroscopic detection using UV fluorescence and fluorescence resonance energy transfer (FRET).

מערבלים microfluidic ללימוד קיפול חלבונים

The process by which a protein folds into its native conformation is highly relevant to biology and human health yet still poorly understood. One reason ...

CometChip: A High-throughput 96-Well Platform for Measuring DNA Damage in Microarrayed Human Cells

DNA damaging agents can promote aging, disease and cancer and they are ubiquitous in the environment and produced within human cells as normal cellular metabolites. Ironically, at high doses DNA damaging agents are also used to treat cancer. The ability to quantify DNA damage responses is thus critical in the public health, pharmaceutical and clinical domains. Here, we describe a novel platform that exploits microfabrication techniques to pattern cells in a fixed microarray. The &#8216;CometChip&#8217; is based upon the well-established single cell gel electrophoresis assay (a.k.a. the comet assay), which estimates the level of DNA damage by evaluating the extent of DNA migration through a matrix in an electrical field. The type of damage measured by this assay includes abasic sites, crosslinks, and strand breaks. Instead of being randomly dispersed in agarose in the traditional assay, cells are captured into an agarose microwell array by gravity. The platform also expands from the size of a standard microscope slide to a 96-well format, enabling parallel processing. Here we describe the protocols of using the chip to evaluate DNA damage caused by known genotoxic agents and the cellular repair response followed after exposure. Through the integration of biological and engineering principles, this method potentiates robust and sensitive measurements of DNA damage in human cells and provides the necessary throughput for genotoxicity testing, drug development, epidemiological studies and clinical assays.

We describe here a platform that allows comet assay detection of DNA damage with unprecedented throughput. The device patterns mammalian cells into a microarray and enables parallel processing of 96 samples. The approach facilitates analysis of base level DNA damage, exposure-induced DNA damage and DNA repair kinetics.

CometChip: תפוקה גבוהה 96-ובכן פלטפורמה למדידת נזק לדנ&quot;א בתאי Microarrayed אדם

DNA damaging agents can promote aging, disease and cancer and they are ubiquitous in the environment and produced within human cells as normal cellular ...

High Throughput Microfluidic Rapid and Low Cost Prototyping Packaging Methods

In this work, 3 different packaging and assembly techniques are presented. They can be classified into two categories: one-time use and reusable packaging techniques.
The one-time use packaging technique employs UV-based and temperature curing epoxies to connect microtubes to access holes, wire-bonding for integrated circuit connections, and silver epoxy for electrical connections. This method is based on a robust assembly technique that can support relatively high pressure close to 1 psi and does not need any support to strengthen the microfluidic architecture.
Reusable packaging techniques consist of PDMS-based microtube interconnectors and anisotropic adhesive films for electrical connections. These devices are more sensitive and fragile. Consequently, Plexiglas support is added to the microfluidic structure to improve the electrical contact when anisotropic adhesive films are used, and also to strengthen the microfluidic architecture. In addition, a micromanipulator is needed to maintain tubes while using a thin PDMS layer to connect them to the access holes. Different PDMS layer thicknesses, ranging from 0.45-3 mm, are tested to compare the best adherence versus injection rates. Applied injection rates are varied from 50-300 &#956;l/hr for 0.45-3 mm PDMS layers, respectively. These techniques are mainly applicable for low-pressure applications. However, they can be extended for high-pressure ones through plasma-oxygen process to permanently seal the PDMS to glass substrates. The main advantage of this technique, besides the fact that it is reusable, consists of keeping the device observable when the microchannel length is very short (in the range of 3 mm or lower).

In this article we describe different techniques for microfluidic rapid prototyping platforms. The proposed techniques are based on ultraviolet (UV) sensitive and temperature curing epoxies, polydimethylsiloxane (PDMS) based tubing, wire-bonding, and anisotropic adhesive films. The assembling procedures presented are developed for both one-time use devices as well as reusable microfluidic systems.

In this work, 3 different packaging and assembly techniques are presented. They can be classified into two categories: one-time use and reusable packaging ...

Cell Squeezing as a Robust, Microfluidic Intracellular Delivery Platform

Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This technology has shown potential in addressing previously challenging applications; including, delivery to primary immune cells, cell reprogramming, carbon nanotube, and quantum dot delivery. This vector-free microfluidic platform relies on mechanical disruption of the cell membrane to facilitate cytosolic delivery of the target material. Herein, we describe the detailed method of use for these microfluidic devices including, device assembly, cell preparation, and system operation. This delivery approach requires a brief optimization of device type and operating conditions for previously unreported applications. The provided instructions are generalizable to most cell types and delivery materials as this system does not require specialized buffers or chemical modification/conjugation steps. This work also provides recommendations on how to improve device performance and trouble-shoot potential issues related to clogging, low delivery efficiencies, and cell viability.

Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This protocol provides detailed steps on how to use the system for a broad range of applications.

לוחץ תא כחזק, Microfluidic תאית פלטפורמה להצגה

Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This ...

Use of a High-throughput In Vitro Microfluidic System to Develop Oral Multi-species Biofilms

There are few high-throughput in vitro systems which facilitate the development of multi-species biofilms that contain numerous species commonly detected within in vivo oral biofilms. Furthermore, a system that uses natural human saliva as the nutrient source, instead of artificial media, is particularly desirable in order to support the expression of cellular and biofilm-specific properties that mimic the in vivo communities. We describe a method for the development of multi-species oral biofilms that are comparable, with respect to species composition, to supragingival dental plaque, under conditions similar to the human oral cavity. Specifically, this methods article will describe how a commercially available microfluidic system can be adapted to facilitate the development of multi-species oral biofilms derived from and grown within pooled saliva. Furthermore, a description of how the system can be used in conjunction with a confocal laser scanning microscope to generate 3-D biofilm reconstructions for architectural and viability analyses will be presented. Given the broad diversity of microorganisms that grow within biofilms in the microfluidic system (including Streptococcus, Neisseria, Veillonella, Gemella, and Porphyromonas), a protocol will also be presented describing how to harvest the biofilm cells for further subculture&#160;or DNA extraction and analysis. The limits of both the microfluidic biofilm system and the current state-of-the-art data analyses will be addressed. Ultimately, it is envisioned that this article will provide a baseline technique that will improve the study of oral biofilms and aid in the development of additional technologies that can be integrated with the microfluidic platform.

Use of a High-throughput In Vitro Microfluidic System to Develop Oral Multi-species Biofilms

The goal of this methods paper is to describe the use of a microfluidic system for the development of multi-species biofilms that contain species typically identified in human supragingival dental plaque.&#160;Methods to describe biofilm architecture, biofilm viability, and an approach to harvest biofilm for culture-dependent or culture-independent analyses are highlighted.

שימוש בתפוקה גבוהה<em&gt; במבחנה</em&gt; מערכת Microfluidic לפתח Biofilms Multi-מינים שבעל פה

There are few high-throughput in vitro systems which facilitate the development of multi-species biofilms that contain numerous species commonly detected ...

A Microfluidic Platform for High-throughput Single-cell Isolation and Culture

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet high-throughput, method to perform single-cell culture experiments. Here, we report a microfluidic chip-based strategy for high-efficiency single-cell isolation (~77%) and demonstrate its capability of performing long-term single-cell culture (up to 7 d) and cellular heterogeneity analysis using clonogenic assay. These applications were demonstrated with KT98 mouse neural stem cells, and A549 and MDA-MB-435 human cancer cells. High single-cell isolation efficiency and long-term culture capability are achieved by using different sizes of microwells on the top and bottom of the microfluidic channel. The small microwell array is designed for precisely isolating single-cells, and the large microwell array is used for single-cell clonal culture in the microfluidic chip. This microfluidic platform constitutes an attractive approach for single-cell culture applications, due to its flexibility of adjustable cell culture spaces for different culture strategies, without decreasing isolation efficiency.

Here, we present a protocol for isolating and culturing single cells with a microfluidic platform, which utilizes a new microwell design concept to allow for high-efficiency single cell isolation and long-term clonal culture.

פלטפורמת Microfluidic עבור בידוד תפוקה גבוהה מתא בודד ותרבות

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet ...

A High-throughput Cell Microarray Platform for Correlative Analysis of Cell Differentiation and Traction Forces

Microfabricated cellular microarrays, which consist of contact-printed combinations of biomolecules on an elastic hydrogel surface, provide a tightly controlled, high-throughput engineered system for measuring the impact of arrayed biochemical signals on cell differentiation. Recent efforts using cell microarrays have demonstrated their utility for combinatorial studies in which many microenvironmental factors are presented in parallel. However, these efforts have focused primarily on investigating the effects of biochemical cues on cell responses. Here, we present a cell microarray platform with tunable material properties for evaluating both cell differentiation by immunofluorescence and biomechanical cell&#8211;substrate interactions by traction force microscopy. To do so, we have developed two different formats utilizing polyacrylamide hydrogels of varying Young&#39;s modulus fabricated on either microscope slides or glass-bottom Petri dishes. We provide best practices and troubleshooting for the fabrication of microarrays on these hydrogel substrates, the subsequent cell culture on microarrays, and the acquisition of data. This platform is well-suited for use in investigations of biological processes for which both biochemical (e.g., extracellular matrix composition) and biophysical (e.g., substrate stiffness) cues may play significant, intersecting roles.

Cell differentiation is regulated by a host of microenvironmental factors, including both matrix composition and substrate material properties. We describe here a technique utilizing cell microarrays in conjunction with traction force microscopy to evaluate both cell differentiation and biomechanical cell&#8211;substrate interactions as a function of microenvironmental context.

פלטפורמת Microarray Cell תפוקה גבוהה עבור ניתוח גומל של התמיינות תאי כוחות המתיחה

Microfabricated cellular microarrays, which consist of contact-printed combinations of biomolecules on an elastic hydrogel surface, provide a tightly ...

A Microfluidic Platform for Longitudinal Imaging in Caenorhabditis elegans

In the last decade, microfluidic techniques have been applied to study small animals, including the nematode Caenorhabditis elegans, and have proved useful as a convenient live imaging platform providing capabilities for precise control of experimental conditions in real time. In this article, we demonstrate live imaging of individual worms employing WormSpa, a previously-published custom microfluidic device. In the device, multiple worms are individually confined to separate chambers, allowing multiplexed longitudinal surveillance of various biological processes. To illustrate the capability, we performed proof-of-principle experiments in which worms were infected in the device with pathogenic bacteria, and the dynamics of expression of immune response genes and egg laying were monitored continuously in individual animals. The simple design and operation of this device make it suitable for users with no previous experience with microfluidic-based experiments. We propose that this approach will be useful for many researchers interested in longitudinal observations of biological processes under well-defined conditions.

A Microfluidic Platform for Longitudinal Imaging in Caenorhabditis elegans

In this article, we demonstrate live imaging of individual worms employing a custom microfluidic device. In the device, multiple worms are individually confined to separate chambers, allowing multiplexed longitudinal surveillance of various biological processes.

פלטפורמה Microfluidic הדמיה האורך ב Caenorhabditis elegans

In the last decade, microfluidic techniques have been applied to study small animals, including the nematode Caenorhabditis elegans, and have proved ...

A Multilayer Microfluidic Platform for the Conduction of Prolonged Cell-Free Gene Expression

The limitations of cell-based synthetic biology are becoming increasingly apparent as researchers aim to develop larger and more complex synthetic genetic regulatory circuits. The analysis of synthetic genetic regulatory networks in vivo is time consuming and suffers from a lack of environmental control, with exogenous synthetic components interacting with host processes resulting in undesired behavior. To overcome these issues, cell-free characterization of novel circuitry is becoming more prevalent. In vitro transcription and translation (IVTT) mixtures allow the regulation of the experimental environment and can be optimized for each unique system. The protocols presented here detail the fabrication of a multilayer microfluidic device that can be utilized to sustain IVTT reactions for prolonged durations. In contrast to batch reactions, where resources are depleted over time and (by-) products accumulate, the use of microfluidic devices allows the replenishment of resources as well as the removal of reaction products. In this manner, the cellular environment is emulated by maintaining an out-of-equilibrium environment in which the dynamic behavior of gene circuits can be investigated over extended periods of time. To fully exploit the multilayer microfluidic device, hardware and software have been integrated to automate the IVTT reactions. By combining IVTT reactions with the microfluidic platform presented here, it becomes possible to comprehensively analyze complex network behaviors, furthering our understanding of the mechanisms that regulate cellular processes.

The fabrication process of a PDMS-based, multilayer, microfluidic device that allows in vitro transcription and translation (IVTT) reactions to be performed over prolonged periods is described. Furthermore, a comprehensive overview of the hardware and software required to automate and maintain these reactions for prolonged durations is provided.

פלטפורמת מיקרופלואידיג רב שכבתית לצורך הובלה של ביטוי גנים ממושך ללא תא

The limitations of cell-based synthetic biology are becoming increasingly apparent as researchers aim to develop larger and more complex synthetic genetic ...

A Microfluidic Platform for Stimulating Chondrocytes with Dynamic Compression

Mechanical stimuli are known to modulate biological functions of cells and tissues. Recent studies have suggested that compressive stress alters growth plate cartilage architecture and results in growth modulation of long bones of children. To determine the role of compressive stress in bone growth, we created a microfluidic device actuated by pneumatic pressure, to dynamically (or statically) compress growth plate chondrocytes embedded in alginate hydrogel cylinders. In this article, we describe detailed methods for fabricating and characterizing this device. The advantages of our protocol are: 1) Five different magnitudes of compressive stress can be generated on five technical replicates in a single platform, 2) It is easy to visualize cell morphology via a conventional light microscope, 3) Cells can be rapidly isolated from the device after compression to facilitate downstream assays, and 4) The platform can be applied to study mechanobiology of any cell type that can grow in hydrogels.

This article provides detailed methods for fabricating and characterizing a pneumatically actuating microfluidic device for chondrocyte compression.

פלטפורמת מיקרופלואידיג לעירור כונדרוציטים עם דחיסה דינמית

Mechanical stimuli are known to modulate biological functions of cells and tissues. Recent studies have suggested that compressive stress alters growth ...

גנרטור ביטוי חלבון תפוקה גבוהה באמצעות פלטפורמת Microfluidic

Summary

Explore More Videos

Chapters in this video