Making tumour cells glow: Medical physicists at Martin Luther University Halle-Wittenberg (MLU) have developed a new method that can generate detailed three-dimensional images of the body's interior. This can be used to more closely investigate the development of cancer cells in the body. The research group presents its findings in "Communication Physics", a journal published by the Nature Publishing Group.
Clinicians and scientists are in need of a better understanding of cancer cells and their properties in order to provide targeted cancer treatment. Individual cancer cells are often examined in test tubes before the findings are tested in living organisms. "
Our aim is to visualise cancer cells inside the living body to find out how they function, how they spread and how they react to new therapies," says medical physicist Professor Jan Laufer from MLU. He specialises in the field of photoacoustic imaging, a process that uses ultrasound waves generated by laser beams to produce high-resolution, three-dimensional images of the body’s interior.
"The problem is that tumour cells are transparent. This makes it difficult to use optical methods to examine tumours in the body," explains Laufer whose research group has developed a new method to solve this problem: First the scientists introduce a specific gene into the genome of the cancer cells.
"Once inside the cells, the gene produces a phytochrome protein, which originates from plants and bacteria. There it serves as a light sensor," Laufer continues. In the next step, the researchers illuminate the tissue with short pulses of light at two different wavelengths using a laser. Inside the body, the light pulses are absorbed and converted into ultrasonic waves.
These waves can then be measured outside the organism and two images of the body's interior can be reconstructed based on this data. "The special feature of phytochrome proteins is that they alter their structure and thus also their absorption properties depending on the wavelength of the laser beams.
This results in changes to the amplitude of the ultrasound waves that are generated in the tumour cells. None of the other tissue components, for example blood vessels, have this property - their signal remains constant," Laufer says. By calculating the difference between the two images, a high-resolution, three-dimensional image of the tumour cells is created, which is free of the otherwise overwhelming background contrast.
The development of Halle's medical physicists can be applied to a wide range of applications in the preclinical research and the life sciences. In addition to cancer research, the method can be used to observe cellular and genetic processes in living organisms.
About the study:
J. Märk et. al, Dual-wavelength 3D photoacoustic imaging of mammalian cells using a photoswitchable phytochrome reporter protein. Communication Physics 2018, 1, 3. DOI: 10.1038/s42005-017-0003-2
Tom Leonhardt | idw - Informationsdienst Wissenschaft
The genes are not to blame
20.07.2018 | Technische Universität München
Targeting headaches and tumors with nano-submarines
20.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences