Atomic force microscopy breakthrough lets us see cells as never before

  Last updated February 23, 2018 at 3:52 pm

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New research has, for the first time, allowed scientists to study changes in cells as they divide, in real time and as they react to their natural environment.


Credit: iStock/adventtr


The breakthrough has come in atomic force microscopy, the technique used, which in the past has not worked for samples in a fluid.


But the new research gets around this problem, allowing amazingly clear images of the variations in elasticity as cells move around and divide.


Every cell in your body is a tiny squishy bag of fluid, like a partially filled water balloon. How squishy – or elastic – each cell is depends on its purpose, health, and what it is doing at the time.


Cells change elasticity by creating or destroying networks of scaffolding made of protein. This happens when cells divide, pulling the cell into two pieces.


Atomic force microscopy works by placing a very sharp needle point near to a sample, and vibrating that needle point up and down using a long lever arm. By measuring the subtle changes in the vibration of the lever arm, we can determine things like the elasticity of the material.


Maps of the stiffness of a HeLa cell at four stages of cell division, starting with interphase (far left) and ending with two daughter cells (far right). Yellow/red/blue show regions of high/medium/low stiffness; scale bars are 10 micrometres.


The problem has been that, having this vibrating lever arm in water, it has been very hard to make precise measurements. To get around this problem, this new research used a specially coated glass needle 10 times longer than the usual metal needles.


These measurements show the differences in squishiness across the cell, and how it changes in space and time during cell division.


The changes are an important part of cell development and variations in elasticity can even identify cancerous cells, so understanding what is going on will have huge biomedical impacts.


“There is a lot of work going on trying to understand changes in the mechanics of cells and how they interact with their environments.“ said Kate Poole, a molecular cell biologist at the University of New South Wales who studies how cells sense touch.


“A high resolution map of interaction forces across the surface of cancerous cell will give us an idea of which structures are responsible for interacting with the environment.”


This will give us insight into how cancers spread.


“When cancerous cells metastasise they have to reach out and grab onto their environment to move around.


“This technique could tell us what structures they are using to do that”, telling us more about the differences between healthy cells and cancerous cells, says Poole.


The research was published in Physical Review Applied.


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Atomic force microscopy breakthrough




About the Author

Anthony Jacko
I am a condensed matter theorist at The University of Queensland. My drive is to systematically understand the properties of molecules, both in isolation and in solid (crystal) form. My ultimate aim is the theoretical design of technologically useful materials from the ground up.