For scientists at the European Molecular Biology Laboratory (EMBL) in Monterotondo, Italy, what seemed like a disappointing result turned out to be an important discovery.
Their findings, published online this week in the journal Proceedings of the National Academy of Sciences (PNAS), provide conclusive proof that, when a muscle is injured, white blood cells called macrophages play a crucial role in its regeneration. The scientists also uncovered the genetic switch that controls this process, a finding that opens the door for new therapeutic approaches not only to sports injuries but also to diseases such as Duchenne muscular dystrophy.
Normally, macrophages – the white blood cells known for engulfing and eliminating bacteria and other infectious agents – are drawn to areas of injury. Once there, they act as garbage men, eliminating the dead cells and releasing pro-inflammatory factors, fending off infection. After clearing up the debris, macrophages stop releasing those pro-inflammatory factors, and start making anti-inflammatory factors that promote repair in the damaged area. This shift from clearing debris to promoting building is known as macrophage polarization, and Claus Nerlov, Nadia Rosenthal and colleagues proved that it is essential for muscles to regenerate properly.
“There seems to be this point of no return”, says Rosenthal: “if macrophages don’t make this switch, then the muscle won’t repair itself – you just end up with scar, instead of new tissue”.
Nerlov and his research group at EMBL were studying a protein called C/EBPâ, whose production increases in response to inflammation. They had genetically engineered mice in which this boost in C/EBPâ production was blocked, to see what effect this had on the development of the different cells involved in the immune system. To their dismay, the answer appeared to be ‘almost none’. The modified mice developed normally, and had normal blood cells – except their macrophages didn’t polarize. Although this result fell short of the scientists’ expectations of understanding how blood cells develop, it raised an interesting possibility in the context of Rosenthal’s research into muscle regeneration. If these mice could not repair muscle injuries properly, it would prove that macrophage polarization is indispensable for muscle regeneration. The two groups teamed up to investigate how the ability to respond to muscle injury was affected in mice whose C/EBPâ production boost had been blocked. Their findings proved that macrophages still migrated to the injured site and cleared the debris, but because they failed to make that all-important switch, the muscle didn’t repair properly, becoming scarred instead.
At a stroke, the EMBL scientists confirmed the importance of macrophages in repairing muscle tissue and discovered its genetic basis. Normally, inflammatory factors trigger an increase in C/EBPâ production, which in turn activates genes that cause the macrophage to polarize.
“From a medical point of view, it would seem that the trick to improve muscle repair is finding a way to increase C/EBPâ production and keep it high”, Nerlov concludes, adding “if we can now figure out exactly which key genes C/EBPâ controls, that will give us even more potential targets.”
As well as investigating the other steps on this molecular pathway, the scientists are currently studying a possible role for macrophage polarization in repairing heart muscle, with a view to better understanding and treating heart disease.Source Article
Lena Raditsch | EMBL
Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex
New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Life Sciences
22.06.2018 | Physics and Astronomy
22.06.2018 | Life Sciences