Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Living cells behave as fluid-filled sponges

Atomic Force Microscopy (AFM) microindentation enables investigation of the dynamic mechanical properties of ‎living ‎cells.‎ Schematic of an AFM cantilever with a spherical tip indenting a cell. The image of the cells (green) is a 3D reconstruction from AFM topographical data. A ‎confocal microscopy image ‎shows the cell profile as the cell is deformed by a spherical bead (blue). The cell membrane is ‎revealed using a fluorescent protein (shown in green) and a ‎fluorescent bead is attached to the ‎cantilever (in blue). Scale bar =10 μm. Below the profile ‎image, a schematic diagram illustrates the ‎indentation of a fluid-filled sponge (poroelastic material). Rapid ‎indentation of the cellular material induces pressurisation ‎of the interstitial fluid leading to its ‎movement out of the compressed area. As the fluid ‎redistributes, the pore ‎pressure diminishes and the reaction force decreases.
Atomic Force Microscopy (AFM) microindentation enables investigation of the dynamic mechanical properties of ‎living ‎cells.‎ Schematic of an AFM cantilever with a spherical tip indenting a cell. The image of the cells (green) is a 3D reconstruction from AFM topographical data. A ‎confocal microscopy image ‎shows the cell profile as the cell is deformed by a spherical bead (blue). The cell membrane is ‎revealed using a fluorescent protein (shown in green) and a ‎fluorescent bead is attached to the ‎cantilever (in blue). Scale bar =10 μm. Below the profile ‎image, a schematic diagram illustrates the ‎indentation of a fluid-filled sponge (poroelastic material). Rapid ‎indentation of the cellular material induces pressurisation ‎of the interstitial fluid leading to its ‎movement out of the compressed area. As the fluid ‎redistributes, the pore ‎pressure diminishes and the reaction force decreases.

Abstract:
Animal cells behave like fluid-filled sponges in response to being mechanically deformed according to new research published in Nature Materials.

Scientists from the London Centre for Nanotechnology at UCL have shown that animal cells behave according to the theory of ‘poroelasticity' when mechanically stimulated in a way similar to that experienced in organs within the body. The results indicate that the rate of cell deformation in response to mechanical stress is limited by how quickly water can redistribute within the cell interior.

Living cells behave as fluid-filled sponges

London, UK | Posted on January 7th, 2013

Poroelasticity was originally formulated to describe the behaviour of water-saturated soils and has important applications in the fields of rock engineering and petro-physics. It ‎is commonly used in the petroleum industry. Poroelastic models describe cells as being analogous to fluid-filled sponges. Indeed, cells are constituted of a sponge-like porous elastic matrix ‎(comprising the cytoskeleton, organelles, and macromolecules) bathed in an interstitial fluid (the cytosol). ‎In this ‎analogy, the rate at which the fluid-filled sponge can be deformed is limited by how fast internal water can redistribute within the sponge in response to deformation. This rate is dictated by three parameters: the stiffness of the sponge matrix, the size of the pores within the sponge matrix, and the viscosity of the interstitial fluid.

To study cellular responses, LCN scientists used cell-sized levers to apply rapid well-controlled deformations on the cell surface and monitored the temporal response of cells to these deformations. Close examination of the experimental results revealed that the rate of cellular deformation was limited by how rapidly water could redistribute within the cell interior. Experimental measurements indicated that this sponge-like behaviour of cells likely occurs during normal function of organs such as the lungs and the cardiovascular system.

Emad Moeendarbary, lead author of the paper from the LCN said:

‎‎"In the cardiovascular system, some tissues encounter extreme mechanical conditions. Heart valves can typically withstand seven-fold increases in their length in less than one second. The poroelastic nature of cells may allow them to behave similarly to shock absorbers when exposed to these extreme mechanical conditions."

To experimentally verify the fluid-sponge model, researchers manipulated the size of the cellular pores using chemical and genetic tools and showed that the rate of cellular deformation was affected by the pore size, as suggested by the theory of poroelasticity.

Guillaume Charras, senior co-author of the paper from the LCN said: "Cells can detect the mechanical forces they are subjected to and modify their behaviour accordingly. How changes in the mechanical environment are converted into biochemical information that the cell can interpret remains unknown. A better understanding of the physics of the cellular material is a first step towards formulating possible mechanisms through which this could occur."

####

For more information, please click here

Contacts:
London Centre for Nanotechnology
17-19 Gordon Street
London WC1H 0AH
tel: +44 (0)20 7679 0604
fax: +44 (0)20 7679 0595

Copyright © London Centre for Nanotechnology

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Journal link: Nature Materials, doi:10.1038/nmat3517:

Related News Press

Imaging

Thin films offer promise for ferroelectric devices: Researchers at Tokyo Institute of Technology demystify the ferroelectric properties observed in hafnium-oxide-based thin films, revealing a potentially useful device material August 3rd, 2015

Take a trip through the brain July 30th, 2015

Publication on Atomic Force Microscopy based nanoscale IR Spectroscopy (AFM-IR) persists as a 2015 top downloaded paper July 29th, 2015

Short wavelength plasmons observed in nanotubes: Berkeley Lab researchers create Ludinger liquid plasmons in metallic SWNTs July 28th, 2015

Announcements

Engineering a better 'Do: Purdue researchers are learning how August 4th, 2015

Proving nanoparticles in sunscreen products August 4th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

Tools

University of Puerto Rico announces August 11th as the launch date for their NASA mission to look for life in space – XEI reports August 3rd, 2015

Thin films offer promise for ferroelectric devices: Researchers at Tokyo Institute of Technology demystify the ferroelectric properties observed in hafnium-oxide-based thin films, revealing a potentially useful device material August 3rd, 2015

Heating and cooling with light leads to ultrafast DNA diagnostics July 31st, 2015

Take a trip through the brain July 30th, 2015

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project