Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tugging at cells with molecules and light

19.12.2016

Research groups in Kiel discover a new method for cellular stimulation

Everyone is made up of approximately 100 trillion cells – if they were laid end to end, they would circle the globe 60 times. Most of these cells arise from mitosis and differentiation of a single egg cell. To orientate themselves, they constantly explore their environment and communicate with their neighbours while they adhere to other cells or surfaces.


Irradiation with green light from below induces a vibration of the signalling molecules (RGD). This mechanical stimulus causes the cells to adhere to the surface.

Rainer Herges

Two working groups from the fields of chemistry and biophysics at Kiel University have discovered a new method for stimulating cells, thereby increasing their adhesion. The results now appear in the renowned journal Angewandte Chemie.

Cells are permanently under attack by bacteria that are attempting to infiltrate them. By contrast, useful bacteria aid digestion or live peacefully on human skin. Cells must communicate continuously and probe their environment to identify friend or foe, or to differentiate themselves from their neighbouring cells. This is why they seek out direct contact with other cells or to their environment.

‘If individual cells are floating in a solution and encounter a surface, they first probe the area to determine whether it is a suitable location to settle. If this is the case, they extend protein sensors to attach themselves. Other cells follow suit, which creates cellular tissue,’ explains Rainer Herges, professor at the Institute of Organic Chemistry.

Cells adhere faster if they are stimulated

Research has long shown that cells respond selectively to certain surface structures and their chemical composition. There are indications that, in addition to static stimuli, dynamic processes such as movements and mechanical forces also have an attracting effect on cells. If, for example, a fine needle is used to tug at cells, this stimulates them to increase their adhesion. ‘However, this is not a very subtle, controlled method, since a large number of different cellular processes are affected,’ reports Christine Selhuber-Unkel, professor for biocompatible nanomaterials at the Institute for Materials Science at Kiel University.

The method that Selhuber-Unkel and Herges now have discovered for stimulating cells is much more sophisticated. They bind chemical recognition structures (so-called RGDs), which are recognised by cells, to surfaces.

However, these signalling molecules do not stand stiff on the surface; instead, they can be moved with light. Tiny molecular switches are incorporated into the tether that binds the RGDs to the surfaces. These molecules bend back and forth approximately 1,000 times per second when they are irradiated with green light. ‘This vibration is transferred to the RGDs, which in turn “pluck” at the cells.

The cells appear to perceive this type of stimulation: they adhere faster and more strongly to the surface,’ explains Selhuber-Unkel. This adhesion strength is measured using an atomic force microscope. The fact that there is increased production of adhesion proteins also indicates that the cells react to this stimulus.

Light as a ‘nanoscalpel’?

The discovery by the researchers in Kiel could trigger a multitude of potential applications. The molecular vibrators can be directly incorporated into cell membranes, which would allow cells to be controlled with light. ‘Use of light as a type of “nanoscalpel” is also conceivable in the long-term; light could be employed to perform extremely precise, microscopic, surgical interventions’, Herges continues.

Research on how to use light to indirectly stimulate cells via molecular switches has been a topic at the Collaborative Research Centre 677 ‘Function by Switching’ since several years. ‘Using light for stimulation has a number of advantages. Firstly, it can be switched on and off in a controlled way,’ explains Herges, the head of the SFB. ‘Moreover, using a laser cells can be irradiated with a resolution of 300 nanometres to detect which areas on the cell are responsible for adhesion.

Thereby, we can elucidate the mechanisms of cellular adhesion.’ Interdisciplinary cooperation was initiated by the framework of the CRC 677. Michelle Holz and Grace Suana from Rainer Herges’ working group in the organic chemistry institute synthesised the switching molecules and surfaces. Laith F. Kadem from Christine Selhuber-Unkel’s working group conducted the cell experiments.

The research project was supported by the CRC 677 ‘Function by Switching’, where 100 scientists from the fields of chemistry, physics, materials science, pharmacy and medicine collaborate to develop molecular switches and machines. It is also supported by an ERC Starting Grant, through which the European Research Council has funded Christine Selhuber-Unkel with €1.5 million since 2013.

Original publication:
Laith F. Kadem, K. Grace Suana, Michelle Holz, Wei Wang, Hannes Westerhaus, Rainer Herges and Christine Selhuber-Unkel. High Frequency Mechanostimulation of Cell Adhesion. Applied Chemistry, 30.11.2016
DOI: 10.1002/anie.201609483 http://dx.doi.org/10.1002/anie.201609483

Contact:
Professor Rainer Herges
Otto Diels-Institut für Organische Chemie
Tel.: +49 (0)431 8802 440
Email: rherges@oc.uni-kiel.de

Professor Christine Selhuber-Unkel
Institut für Materialwissenschaft
Tel.: +49 (0)431 8806 198
Email: cse@tf.uni-kiel.de

Weitere Informationen:

http://www.uni-kiel.de/pressemeldungen/index.php?pmid=2016-426-zellhaftung&l...

Dr. Boris Pawlowski | Christian-Albrechts-Universität zu Kiel

More articles from Materials Sciences:

nachricht Additive manufacturing reflects fundamental metallurgical principles to create materials
18.01.2019 | University of Sheffield

nachricht Brilliant glow of paint-on semiconductors comes from ornate quantum physics
17.01.2019 | Georgia Institute of Technology

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Ten-year anniversary of the Neumayer Station III

The scientific and political community alike stress the importance of German Antarctic research

Joint Press Release from the BMBF and AWI

The Antarctic is a frigid continent south of the Antarctic Circle, where researchers are the only inhabitants. Despite the hostile conditions, here the Alfred...

Im Focus: Ultra ultrasound to transform new tech

World first experiments on sensor that may revolutionise everything from medical devices to unmanned vehicles

The new sensor - capable of detecting vibrations of living cells - may revolutionise everything from medical devices to unmanned vehicles.

Im Focus: Flying Optical Cats for Quantum Communication

Dead and alive at the same time? Researchers at the Max Planck Institute of Quantum Optics have implemented Erwin Schrödinger’s paradoxical gedanken experiment employing an entangled atom-light state.

In 1935 Erwin Schrödinger formulated a thought experiment designed to capture the paradoxical nature of quantum physics. The crucial element of this gedanken...

Im Focus: Nanocellulose for novel implants: Ears from the 3D-printer

Cellulose obtained from wood has amazing material properties. Empa researchers are now equipping the biodegradable material with additional functionalities to produce implants for cartilage diseases using 3D printing.

It all starts with an ear. Empa researcher Michael Hausmann removes the object shaped like a human ear from the 3D printer and explains:

Im Focus: Elucidating the Atomic Mechanism of Superlubricity

The phenomenon of so-called superlubricity is known, but so far the explanation at the atomic level has been missing: for example, how does extremely low friction occur in bearings? Researchers from the Fraunhofer Institutes IWM and IWS jointly deciphered a universal mechanism of superlubricity for certain diamond-like carbon layers in combination with organic lubricants. Based on this knowledge, it is now possible to formulate design rules for supra lubricating layer-lubricant combinations. The results are presented in an article in Nature Communications, volume 10.

One of the most important prerequisites for sustainable and environmentally friendly mobility is minimizing friction. Research and industry have been dedicated...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Our digital society in 2040

16.01.2019 | Event News

11th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Aachen, 3-4 April 2019

14.01.2019 | Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

 
Latest News

Additive manufacturing reflects fundamental metallurgical principles to create materials

18.01.2019 | Materials Sciences

How molecules teeter in a laser field

18.01.2019 | Life Sciences

The cytoskeleton of neurons has been found to be involved in Alzheimer's disease

18.01.2019 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>