Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Observing inflammatory cells in the body: new method for preclinical research

18.04.2018

Immunologists and imaging specialists at the Cells-in-Motion Cluster of Excellence have jointly developed a method enabling them to better evaluate and study the activity of inflammatory cells in mice. The study has been published in the “Theranostics” journal.

The process that the body sets in motion in the event of inflammation is complex, but also impressive. The main role here is played by immune cells migrating from the blood into the tissue to fight the inflammation. If too many of these cells are active, however, they can just as easily cause damage.


Immune cells (red) in a mouse. Top: genetically unmodified cells. Bottom: cells lacking the VLA4 protein. Images were taken 3 hours (l.), 24 hours (m.) and 48 hours (r.) after cell injection.

© S. Gran & L. Honold et al./Theranostics 2018(8)

Finding out more about the cells’ behaviour can provide a basis for researchers to develop individual treatments for inflammation – for example, by guiding cells specifically towards the centre of the inflammation or through a timely discontinuation of a certain treatment.

Researchers at the Cells-in-Motion Cluster of Excellence at the University of Münster have now developed a method enabling them to better evaluate and study the activity of inflammatory cells in mice: they have succeeded in genetically modifying precursors of immune cells, then increasing their numbers in a test tube and finally tracking them spatially and temporally in living organisms.

This process was made possible by interdisciplinary collaboration between immunologists and molecular imaging specialists. The new method also means that the number of animal experiments can be greatly reduced. The study has been published in the “Theranostics” journal.

The detailed story:

When the body wards off an infection, it is initially various types of scavenger cells, so-called phagocytes, which migrate successively out of the blood vessels and into the tissue, to the inflammation centre. They recognize pathogens, “eat them up” and kill them. If they are activated in an uncontrolled way, however, they can also drive disease progression. In order to investigate the migratory mechanisms of various phagocytes, researchers usually study genetically modified mice which display inflammatory diseases.

This is not easy, however, as it requires a large number of immune cells and a lot of mice need to be bred as donors. A team of immunologists headed by Prof. Johannes Roth, a group leader at the Cluster of Excellence, have now solved this problem with their new approach.

They used immortalized myeloid precursor cells – so-called ERHoxb8 cells – which multiply almost endlessly in a test tube and, under certain conditions, can develop into immune cells. In this way, the researchers ultimately obtained a large number of different types of phagocytes.

“Our next aim was to produce genetic modifications to the cells, such as occur for example in innate immune deficiencies,” says Johannes Roth. Such mutations often affect proteins in the membranes of immune cells, which help them to get to sites of inflammation. One of these proteins is VLA4. However, researchers have only limited possibilities to study what exactly happens when the protein is missing because it is very difficult for them to breed the necessary mouse strains.

The Münster immunologists found a test-tube alternative for this, too: they used the molecular biological method of genome editing to systematically “cut out” the gene segment relevant for VLA4 and produce the appropriate “deficient” immune cells. “As a result of our new method,” says Dr. Sandra Gran, one of the two lead authors of the study, “we can now, for the first time, genetically modify different types of immune cells at will and deactivate important inflammation mechanisms.”

Imaging using optical and nuclear medical methods

The group of imaging specialists led by Prof. Michael Schäfers, Coordinator of the Cluster of Excellence, labelled the cells thus obtained with various fluorescent dyes in order to be able to study them in living organisms – initially with the optical method of fluorescence reflectance imaging. They injected into mice with an inflammatory skin disease both mutated and healthy immune cells and succeeded in comparing the paths taken by each of the cells inside the same animal.

This enabled them to greatly reduce the number of laboratory animals, because usually different groups of animals have to be used for such comparative studies. The new method worked: “We were able to observe very precisely how differently the various immune cells behaved,” says Dr. Lisa Honold, the other lead author of the study. Using the same method, the researchers examined further cells which were lacking other membrane proteins.

In a further step, the researchers looked at migrating immune cells in mice which had experienced a heart attack. Naturally enough, such examinations present a great challenge because the heart is located deep within the body and moves very fast when pumping. The researchers used a nuclear medical imaging method – known as single photon emission tomography, SPECT for short – enabling them to produce digital cross-sections from deep layers of tissue.

They labelled the cells in the test tube with a radioactive substance whose radiation can be measured and visualized in images. After they had injected the labelled cells to mice, they tracked their locations in various phases of the infarct. “By using serial imaging, we can now follow the behaviour of immune cells over a long period of time,” says Nuclear Medicine Professor Michael Schäfers. This should also lead to a reduction in the number of laboratory animals needed because traditional molecular biological methods merely produce snapshots and require many more experiments.

The researchers intend to make use of their new method in preclinical studies in the future and continue to develop it – for example, applying it to infections and to rheumatological and arthritic diseases. As yet, however, it cannot be predicted when the results can be used to benefit patients.

Funding:

The study was produced as part of an interdisciplinary Flexible Funds Project at the Cells-in-Motion Cluster of Excellence at the University of Münster. It received further funding from Collaborative Research Centres 656 (“Molecular Cardiovascular Imaging”) and 1009 (“Breaking Barriers”), funded by the German Research Foundation, as well as from the Interdisciplinary Center of Clinical Research at Münster University. The German Federal Ministry of Education and Research also provided financial assistance.

Original publication:

Gran S, Honold L, Fehler O, Zenker S, Eligehausen S, Kuhlmann MT, Geven E, van den Bosch M, van Lent P, Spiekermann C, Hermann S, Vogl T, Schäfers M, Roth J. Imaging, myeloid precursor immortalization, and genome editing for defining mechanisms of leukocyte recruitment in vivo. Theranostics 2018;8: 2407-2423; DOI: 10.7150/thno.23632

Weitere Informationen:

https://www.uni-muenster.de/Cells-in-Motion/de/people/all/roth.php Prof. Johannes Roth
https://www.uni-muenster.de/Cells-in-Motion/de/people/all/schaefers-m.php Prof. Michael Schäfers
https://www.uni-muenster.de/Cells-in-Motion/de/research/projects/flexible-funds/... Overview of Flexible Funds Projects at the Cluster of Excellence

Svenja Ronge | idw - Informationsdienst Wissenschaft

Further reports about: Cluster immune cells inflammatory inflammatory cells phagocytes proteins test tube

More articles from Life Sciences:

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

nachricht Pollen taxi for bacteria
18.07.2018 | Technische Universität München

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

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...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

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...

Im Focus: Breaking the bond: To take part or not?

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...

Im Focus: New 2D Spectroscopy Methods

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....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>