Name: quantitative and temporal control of oxygen microenvironment at the single islet level
Uploaded: 2013-11-17T14:00:00
Description: Watch this Scientific Journal Video about Quantitative and Temporal Control of Oxygen Microenvironment at the Single Islet Level at JoVE.com

This work was supported by the National Institutes of Health Grants R01 DK091526 (JO), NSF 0852416(DTE), and Chicago Diabetes Project.

1. Preparing the Mouse Islets
<ol>
	<li>Dissect C57BL/6 mice and isolate islets by collagenase digestion and Ficoll density gradient separation. (Refer to JOVE articles referenced in2,3).</li>
	<li>Incubate islets in RPMI-1640 medium containing 10% FBS, 1% penicillin/streptomycin, and 20 mM HEPES in Petri&#160;dishes (37 &#176;C, 5% CO2). Post-isolation, culture islets for 24 hr prior to use in experiments. Use the islets within 1-2 days to ensure consistent results.</li>
</ol>
<p class="jove_titl...

<ol>
	<li>Lo, J. F., Wang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Islet+Preconditioning+via+Multimodal+Microfluidic+Modulation+of+Intermittent+Hypoxia.">Islet Preconditioning via Multimodal Microfluidic Modulation of Intermittent Hypoxia.</a> Anal. Chem. 84 (4), 1987-1993 (2012).</li><li>Qi, M., Barbaro, B., Wang, S., Wang, Y., Hansen, M., Oberholzer, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+Pancreatic+Islet+Isolation:+Part+I:+Digestion+and+Collection+of+Pancreatic+Tissue.">Human Pancreatic Islet Isolation: Part I: Digestion and Collection of Pancreatic Tissue.</a> J. Vis. Exp.. , e1125 (2009).</li><li>Qi, M., Barbaro, B., Wang, S., Wang, Y., Hansen, M., Oberholzer, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+Pancreatic+Islet+Isolation:+Part+II:+Purification+and+Culture+of+Human+Islets.">Human Pancreatic Islet Isolation: Part II: Purification and Culture of Human Islets.</a> J. Vis. Exp.. , e1343 (2009).</li><li>Shapiro, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Islet+Transplantation+in+Seven+Patients+with+Type+1+Diabetes+Mellitus+Using+a+Glucocorticoid-Free+Immunosuppressive+Regimen.">Islet Transplantation in Seven Patients with Type 1 Diabetes Mellitus Using a Glucocorticoid-Free Immunosuppressive Regimen.</a> N. Engl. J. Med. 343 (4), 230-238 (2000).</li><li>Adewola, A. F., Wang, Y., Harvat, T., Eddington, D. T., Lee, D., Oberholzer, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Multi-Parametric+Islet+Perifusion+System+within+a+Microfluidic+Perifusion+Device.">A Multi-Parametric Islet Perifusion System within a Microfluidic Perifusion Device.</a> J. Vis. Exp.. , e1649 (2010).</li><li>Mohammed, J. S., Wang, Y., Harvat, T. A., Oberholzer, J., Eddington, D. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidic+device+for+multimodal+characterization+of+pancreatic+islets.">Microfluidic device for multimodal characterization of pancreatic islets.</a> Lab Chip. 9, 97-106 (2009).</li><li>Carreras, A., Kayali, F., Zhang, J., Hirotsu, C., Wang, Y., Gozal, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+Effects+Of+Intermittent+Hypoxia+In+Mice:+Steady+Versus+High+Frequency+Applied+Hypoxia+Daily+During+The+Rest+Period.">Metabolic Effects Of Intermittent Hypoxia In Mice: Steady Versus High Frequency Applied Hypoxia Daily During The Rest Period.</a> AJP - Regu Physiol. 303 (7), 700-709 (2012).</li><li>Lee, E. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time-dependent+changes+in+glucose+and+insulin+regulation+during+intermittent+hypoxia+and+continuous+hypoxia.">Time-dependent changes in glucose and insulin regulation during intermittent hypoxia and continuous hypoxia.</a> Eur. J. Appl. Physiol. , (2012).</li><li>Kane, B. J., Zinner, M. J., Yarmush, M. L., Toner, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liver-specific+functional+studies+in+a+microfluidic+array+of+primary+mammalian+hepatocytes.">Liver-specific functional studies in a microfluidic array of primary mammalian hepatocytes.</a> Anal. Chem. 78, 4291-4298 (2006).</li><li>Lam, R. H. W., Kim, M. C., Thorsen, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Culturing+aerobic+and+anaerobic+bacteria+and+mammalian+cells+with+a+microfluidic+differential+oxygenator.">Culturing aerobic and anaerobic bacteria and mammalian cells with a microfluidic differential oxygenator.</a> Anal. Chem. 81, 5918-5924 (2009).</li><li>Polinkovsky, M., Gutierrez, E., Levchenko, A., Groisman, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fine+temporal+control+of+the+medium+gas+content+and+acidity+and+on-chip+generation+of+series+of+oxygen+concentrations+for+cell+cultures.">Fine temporal control of the medium gas content and acidity and on-chip generation of series of oxygen concentrations for cell cultures.</a> Lab Chip. 9, 1073-1084 (2009).</li><li>Mehta, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+measurement+and+control+of+oxygen+levels+in+microfluidic+poly(dimethylsiloxane)+bioreactors+during+cell+culture.">Quantitative measurement and control of oxygen levels in microfluidic poly(dimethylsiloxane) bioreactors during cell culture.</a> Biomed. Microdev. 9 (2), 123-134 (2007).</li><li>Vollmer, A. P., Probstein, R. F., Gilbert, R., Thorsen, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+an+integrated+microfluidic+platform+for+dynamic+oxygen+sensing+and+delivery+in+a+flowing+medium.">Development of an integrated microfluidic platform for dynamic oxygen sensing and delivery in a flowing medium.</a> Lab Chip. 5, 1059-1066 (2005).</li><li>Chen, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+oxygen+gradients+in+microfluidic+devices+for+cell+culture+using+spatially+confined+chemical+reactions.">Generation of oxygen gradients in microfluidic devices for cell culture using spatially confined chemical reactions.</a> Lab Chip. 11, 3626-3633 (2011).</li><li>Lo, J. F., Sinkala, E., Eddington, D. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oxygen+gradients+for+open+well+cellular+cultures+via+microfluidic+substrates.">Oxygen gradients for open well cellular cultures via microfluidic substrates.</a> Lab Chip. 10, 2394-2401 (2010).</li></ol>

The multiple modalities integrated in this islet hypoxia technique present several points noted here for troubleshooting. First the isolated islets continue to degrade and disintegrate in culture due to digestive enzymes from acinar cells. Standardizing experiments to 1-2 days after islet isolation is thus critical in obtaining consistent results. Second, the aqueous flow was stopped during hypoxia and intermittent hypoxia to prevent convective clearance at the boundary between laminar flow and diffusion. This seems to l...

Dynamic hypoxia is important in biology, specifically for islet transplants
Dynamic hypoxia is an important physiological as well as pathophysiological parameter in many biological tissues. Change in oxygen, for example, is a potent developmental signal in angiogenesis. Moreover, spatial and temporal patterns in hypoxia modulate HIF1-alpha and play roles in diseases like pancreatic cancer. Hypoxia is also a confounding factor affecting islet transplant outcomes. Recently, temporally oscillations of hypoxia, or intermittent hypoxia (IH) have demonstrated benefits in &#34;preconditioning&#34; islets1. However, both static and transient hypoxia effects on islet physiology have yet to be well understood or studied, primarily due to the lack of appropriate tools to control islet&#39;s microenvironment.
Islets are well vascularized in vivo
Pancreatic islets are 50-400 &#956;m spheroidal aggregates of endocrine cells, including beta-cells and alpha-cells that are responsible for glucose homeostasis. When islets are exposed to stimulatory glucose in the blood, uptake and glycolysis lead to ATP production, which opens up ATP-sensitive potassium (KATP) channels and results in calcium influx that triggers the exocytosis of insulin granules. Oxygen is important to drive this heavily metabolic process and insulin secretion is significantly influenced by the dynamics of blood flow and oxygen supply in addition to glucose gradients. Islets readily perform this glucose-insulin response in vivo as they are highly perfused in the pancreas, each within one cell length from a capillary vessel. However, the dense network of intraislet capillaries is removed by collagenase during islet isolation2,3. Consequently, both oxygen and nutrient supplies are constrained to a 100 &#956;m perimeter due to diffusion limitations.
Current techniques have limited success in recreating islet microenvironment
Recreating islet&#39;s native oxygen and glucose dynamics, key to modeling physiological and pathophysiological conditions, is difficult to achieve with standard hypoxic chambers that require elaborate flow and lack continuous monitoring of islet functions. Moreover, transplant therapies for Type I diabetes expose isolated islets to hypoxia in the hepatic portal system4 which has much lower pO2 (&#60;2%, 5-15 mmHg) compared to physiological pancreas (5.6%, 40 mmHg). Post-transplant, the islet grafts take two weeks or more to be revascularized. It has been demonstrated that hypoxic exposure impairs islet&#39;s glucose-insulin coupling mechanism. Among the stimulus-secretion coupling factors, calcium signaling, mitochondrial potentials, and insulin kinetics can be easily monitored using microfluidics. Our previous microfluidic technique demonstrated this real-time monitoring with precise modulation of the aqueous microenvironment around single islet5,6. However, quantification of islet&#39;s hypoxic impairment is stymied by the lack of simultaneous stimulation and monitoring techniques. Therefore, combining microfluidic control of oxygen and islet monitoring can improve islet hypoxia studies.
Microfluidics can recreate and modulate the aqueous and oxygen microenvironment
The standard technique for tissue and culture hypoxia studies has been based on hypoxic chambers. In general, the hypoxic chambers provide single oxygen concentrations with equilibration times in ~10-30 min, incompatible with minute-scaled dynamic hypoxia. Two recent studies used small custom chambers for intermittent hypoxia exposure on whole mice, with conflicting results on glucose-induced insulin response7,8. Bear in mind that at the whole animal level, the respired oxygen is not directly translated to islet capillary pO2, due to controls in the respiratory system. Furthermore, these studies do not have standardized oxygen levels, nor do they provide real-time measures at the tissue level of islets.
On the other hand, oxygen microfluidics can surpass these limitations by controlling oxygen via gas channel networks. Moreover, microfluidics is compatible with live imaging during oxygen modulation, a feat currently not possible with standard hypoxic chambers. A number of these novel microfluidics approaches utilize the gas permeability of polydimethylsiloxane to dissolve oxygen concentrations into microchannels that flow media over target cells9-14. These devices have also integrated multiple discrete oxygen concentrations, fluorescence based oxygen sensors, and even chemical oxygen generation on-chip.
Liquid solvation-based microfluidics have a hard time maintaining stable, continuous gradients as it depends on convective mixing which is sensitive to flow conditions. In comparison, the technique we use here focuses on decreasing the diffusion path of oxygen delivery. The gas solvation and shear flow are eliminated by directly diffusing oxygen across a membrane seeded with cells or islet tissues. This removes the extra microfluidics required to control solvation and prevents unnecessary shear stress to the islets, which itself can trigger insulin release. This platform has been used to demonstrate reactive oxygen species (ROS) up-regulation at both hyperoxic and hypoxic extremes (2-97% O2) in cell culture1,15. Because of the direct delivery of oxygen and removal of shear flow, our diffusion-based platform provides the optimal microfluidic solution for studying islet hypoxia.
Multimodal stimulation and monitoring
Diffusion-based microfluidics also brings additional benefits when adapted for studying islet microphysiology. By using a membrane as a diffusion barrier, the liquid can be isolated from the oxygen modulations, enabling controls of aqueous glucose stimulations independently from hypoxic stimulations. This creates a sandwich-like simultaneous stimulation that spatially pin-points delivery to the islets. Furthermore, as the gas is temporally modulated via computerized microinjectors, we can modulate the oxygen concentration from 21-0% digitally with transient time less than 60 sec. The dynamic controls of the oxygen and glucose microenvironment at the microscope allow a real-time multimodal protocol that would not be possible or extraordinarily cumbersome using standard hypoxic chambers. Using this device, calcium signaling (Fura-AM), mitochondrial potentials (Rhodamine 123), and insulin kinetics (ELISA) were monitored to provide a complete picture of the dynamic glucose-insulin response under hypoxia.

<table border="1">
	<tbody>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Reagent/Material</td>
		</tr>
		<tr>
			<td>Spinner</td>
			<td>Laurell</td>
			<td>WS-400</td>
			<td></td>
		</tr>
		<tr>
			<td>SU8</td>
			<td>MicroChem</td>
			<td>SU8-2150/SU8-2100</td>
			<td></td>
		</tr>
		<tr>
			<td>Digital Hotplate</td>
			<td>PMC Dataplate</td>
			<td>722A</td>
			<td></td>
		</tr>
		<tr>
			<td>UV Curing Lamp</td>
			<td>OmniCure</td>
			<td>S1000</td>
			<td></td>
		</tr>
		<tr>
			<td>PMDS</td>
			<td>Dow Chemical</td>
			<td>Sylgard 184</td>
			<td></td>
		</tr>
		<tr>
			<td>Corona Wand</td>
			<td>ETP</td>
			<td>BD-20AC</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum Chamber</td>
			<td>Bel-Art</td>
			<td>420220000</td>
			<td></td>
		</tr>
		<tr>
			<td>Microdispensers</td>
			<td>The Lee Company</td>
			<td>IKTX0322000A</td>
			<td></td>
		</tr>
		<tr>
			<td>5 V and 20 V DC Power</td>
			<td>Radio Shack</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>NI USB</td>
			<td>National Instrument</td>
			<td>NI USB-6501</td>
			<td></td>
		</tr>
		<tr>
			<td>Thermometer</td>
			<td>Omega Engineering, Inc.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Peristaltic Pump</td>
			<td>Gilson</td>
			<td>Minipulse 2</td>
			<td></td>
		</tr>
		<tr>
			<td>Oxygen Sensor</td>
			<td>Ocean Optics</td>
			<td>NeoFox</td>
			<td></td>
		</tr>
		<tr>
			<td>Fraction Collector</td>
			<td>Gilson</td>
			<td>203</td>
			<td></td>
		</tr>
		<tr>
			<td>Pippette</td>
			<td>Fisher Scientific</td>
			<td>Finnpipette II 100&#956;l</td>
			<td></td>
		</tr>
		<tr>
			<td>Inverted Epifluorescence Microscope</td>
			<td>Leica</td>
			<td>DMI 4000B</td>
			<td></td>
		</tr>
		<tr>
			<td>50 ml Conical Tubes</td>
			<td>Fisher Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fura-2 Fluorescence Dye</td>
			<td>Molecular Probes, Life Technologies</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Rhodamine 123 Fluorescence Dye</td>
			<td>Molecular Probes, Life Technologies</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Culture Media</td>
			<td>Sigma-Aldrich</td>
			<td>RPMI-1640</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Sigma-Aldrich</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Glucose</td>
			<td>Sigma-Aldrich</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin</td>
			<td>Sigma-Aldrich</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>30 in Silicone Tubings</td>
			<td>Cole-Parmer</td>
			<td></td>
			<td>1/16 in x 1/8 in</td>
		</tr>
		<tr>
			<td>1.5 ml Eppendorf Tubes</td>
			<td>Fisher Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Y-connectors</td>
			<td>Cole-Parmer</td>
			<td></td>
			<td>1/16 in and 4 mm</td>
		</tr>
		<tr>
			<td>Syringe Connectors</td>
			<td>Cole-Parmer</td>
			<td></td>
			<td>female Luer plug 1/16 in</td>
		</tr>
		<tr>
			<td>Straight Connectors</td>
			<td>Cole-Parmer</td>
			<td></td>
			<td>1/16 in</td>
		</tr>
		<tr>
			<td>Elbow Connector</td>
			<td>Cole-Parmer</td>
			<td></td>
			<td>1/16 in</td>
		</tr>
	</tbody>
</table>

quantitative and temporal control of oxygen microenvironment at the single islet level

Oxygénation simultanée et la surveillance de glucose stimulus-sécrétion de facteurs de couplage dans une seule technique est essentielle pour la modélisation états physiopathologiques de l&#39;îlot hypoxie, en particulier dans les environnements de transplantation. Techniques de la chambre hypoxique standard ne peuvent pas moduler les stimulations en même temps, ni assurer le suivi en temps réel des facteurs de couplage stimulus-sécrétion glucose. Pour répondre à ces difficultés, nous avons appliqué une technique microfluidique multicouche à intégrer à la fois aqueuse et modulations de phase de gaz par une membrane de diffusion. Cela crée un sandwich de stimulation autour des îlots microscaled sein du polydiméthylsiloxane transparent (PDMS) de l&#39;appareil, ce qui permet la surveillance des éléments d&#39;accouplement susmentionnés par microscopie à fluorescence. En outre, l&#39;entrée de gaz est commandé par une paire de microdispensers, en fournissant des modulations quantitatives, les sous-minute d&#39;oxygène entre 0-21%. Cette hypoxie intermittente est utilisée pour étudier un nouveau phénomène de l&#39;Islet préconditionnement. En outre, armés de microscopie multimodale, nous avons pu regarder calcium détaillée et K ATP dynamique de canal lors de ces événements hypoxiques. Nous envisageons l&#39;hypoxie microfluidique, en particulier cette technique à deux phases simultanément, comme un outil précieux pour l&#39;étude des îlots ainsi que de nombreux ex vivo des tissus.

Central to this islet hypoxia technique is the ability to modulate aqueous and gaseous phase stimulation in the same microfluidic chamber with minute-scale transients. Figure 1 is a representative result of the a) dual stimulations and b) fast modulations measured within the islet chamber. Aqueous modulation, shown by introduction of fluorescein into the chamber, achieves equilibrium in three to four minutes of mixing. Furthermore, oxygen can be stepped from 5-21% with fast transients, enabling cycling o...

Watch this Scientific Journal Video about Quantitative and Temporal Control of Oxygen Microenvironment at the Single Islet Level at JoVE.com

Quantitative and Temporal Control of Oxygen Microenvironment at the Single Islet Level

Microfluidic oxygen control confers more than just convenience and speed over hypoxic chambers for biological experiments. Especially when implemented via diffusion through a membrane, microfluidic oxygen can provide simultaneous liquid and gas phase modulations at the microscale-level. This technique enables dynamic multi-parametric experiments critical for studying islet pathophysiology.

Contrôle quantitatif et temporelle des micro-environnement de l&#39;oxygène à l&#39;Islet Plain

Simultaneous oxygenation and monitoring of glucose stimulus-secretion coupling factors in a single technique is critical for modeling pathophysiological ...

Research

JoVE Journal

Bioengineering

A Microfluidic-based Hydrodynamic Trap for Single Particles

Un piège hydrodynamique microfluidique à base de particules uniques

The ability to confine and manipulate single particles in free solution is a key enabling technology for fundamental and applied science.  Methods for ...

Recherche

Bio-ingénierie

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells

Spatio-temporelle de manipulation de l&#39;activité GTPase Petit au niveau subcellulaire et sur des échelles de secondes dans les cellules vivantes

Dynamic regulation of the Rho family of small guanosine triphosphatases (GTPases) with great spatiotemporal precision is essential for various cellular ...

Engineering a Bilayered Hydrogel to Control ASC Differentiation

Le façonnage d&#39;une bicouche Hydrogel de contrôler la différenciation ASC

Natural polymers over the years have gained more importance because of their host biocompatibility and ability to interact with cells in vitro and in ...

Nanomanipulation of Single RNA Molecules by Optical Tweezers

Nanomanipulation de molécules d&#39;ARN simple par pinces optiques

A large portion of the human genome is transcribed but not translated. In this post genomic era, regulatory functions of RNA have been shown to be ...

A Label-free Technique for the Spatio-temporal Imaging of Single Cell Secretions

Une technique Label-free pour l&#39;imagerie spatio-temporelle de cellule unique sécrétions

Inter-cellular communication is an integral part of a complex system that helps in maintaining basic cellular activities. As a result, the malfunctioning ...

Engineering Molecular Recognition with Bio-mimetic Polymers on Single Walled Carbon Nanotubes

Reconnaissance moléculaire Ingénierie avec Polymères Bio-mimétiques sur simple Walled Carbon Nanotubes

Semiconducting single-wall carbon nanotubes (SWNTs) are a class of optically active nanomaterial that fluoresce in the near infrared, coinciding with the ...

A Microfluidic System with Surface Patterning for Investigating Cavitation Bubble(s)&#8211;Cell Interaction and the Resultant Bioeffects at the Single-cell Level

A Microfluidic System with Surface Patterning for Investigating Cavitation BubblesÃƒÆ’Ã‚Â¢ÃƒÂ¢Ã¢â‚¬Å¡Ã‚Â¬ÃƒÂ¢Ã¢â€šÂ¬Ã…â€œCell Interaction and the Resultant Bioeffects at the Single-cell Level

Un système microfluidique avec Patterning de surface pour les enquêtes cavitation Bubble (s) Interaction -Cell et les effets biologiques résultantes au niveau d&#39;une seule cellule

In this manuscript, we first describe the fabrication protocol of a microfluidic chip, with gold dots and fibronectin-coated regions on the same glass ...

An Ultrahigh-throughput Microfluidic Platform for Single-cell Genome Sequencing

Une plate-forme de Microfluidic ultra haute capacité pour le séquençage du génome de cellules individuelles

Sequencing technologies have undergone a paradigm shift from bulk to single-cell resolution in response to an evolving understanding of the role of ...

Patterning the Geometry of Human Embryonic Stem Cell Colonies on Compliant Substrates to Control Tissue-Level Mechanics

Modelage de la géométrie des colonies de cellules souches embryonnaires humaines sur des substrats conformes pour contrôler la mécanique de niveau tissulaire

Human embryonic stem cells demonstrate a unique ability to respond to morphogens in vitro by self-organizing patterns of cell fate specification that ...