Author: Jin Nan Release Date: 2018-08-22 In the brain tissue of mice at low resolution (left) and high resolution (right), infrared spectroscopy distinguishes astrocytes from neurons. Image source: ARIS POLYZOS & LILA LOVERGNE In order to observe cells, researchers often have to "abuse" it: pick it up from the "home", soak it with a toxic fixative, modify its DNA, and force it to produce heterogeneous proteins that may disrupt biochemical properties. . Even if this cell survives, it can never be the original cell. But one day, a strong, gentle light can be used to classify researchers without harming cells and making them alive for other research. A team led by biophysicist Cynthia McMurray of the Lawrence Berkeley National Laboratory (LBNL) and physicist Michael Martin found that by scanning the cells with intense infrared radiation generated by a synchrotron, they capture a revelation Biochemical markers of cell characteristics. The researchers reported the preliminary results of the method at a meeting in the UK in June this year, and they are now evaluating it with a one-year trial grant from the Chen Zuckerberg Initiative (CZI). If the method works, the team's spectral phenotypic technology will provide tools for another CZI-supported project. The international collaboration project called the Human Cell Atlas aims to map the types of each cell in the human body. And location. If the synchrotron driving method is applied to softer infrared instruments used in other laboratories and hospitals, then spectral phenotypic technology may one day help diagnose disease, detect cell changes that cause disease, and understand embryo development. "The tools we use will make this area a new look." McMurray predicts. Scientists familiar with the unpublished results say the method is promising. Peter Gardner, a chemist at the University of Manchester in the UK, said: "I am looking forward to seeing the results of this study." Hugh Byrne, a chemical physicist at Dublin Institute of Technology, was impressed with how the team thoroughly tested the method. He said, "This is an appropriate study to prove the potential of the technology." Martin and McMurray like to compare their approach to another widely used cell identification technique: fluorescent labeling. To stimulate specific types of cells to produce markers such as green fluorescent protein (GFP), scientists need to equip them with relevant molecular genes. But the technique of adding DNA changes cells because GFP is foreign to them - from a jellyfish that changes the physiology of the cells. In addition, McMurray pointed out that researchers often need to use a laser to illuminate a fluorescent tag to cause it to illuminate, which can damage or kill cells. Other technologies are also somewhat invasive. "If you mark or stain, it will change the true chemical properties of the cells," Martin said. "We want to explore the chemistry of the cells, not to make changes after making measurements." This is where infrared spectroscopy technology comes in handy. "Infrared is not invasive, so it can be used for unaffected tissues and living cells," McMurray said. When a sample is exposed to infrared radiation of different wavelengths, the amount of infrared light it absorbs in each band can indicate the type of chemical group contained therein. Unlike fluorescent labels, this mode of absorption usually does not reveal whether cells are producing a particular molecule, such as the immunoreceptor CD4 or CD8, which are often used to define two types of T cells. But the infrared spectral characteristics of cells can indeed reveal a wide range of cell types, such as fats and proteins, to provide biochemical fingerprints. So, "you can get a more comprehensive picture of the cells," Byrne said. Martin and McMurray said that the standard infrared source does not provide the sensitivity they need, so the team turned to LBNL's advanced light source synchrotron, which produces one of the brightest beams in the world. Martin said: "It allows us to achieve higher resolution and fidelity." At the SPEC2018 meeting in Glasgow in June, McMurray and Martin said they can distinguish between two brain cells in a mouse brain slice - - neurons and astrocytes. In rodent brain tissue that mimics the symptoms of Huntington's disease, they also detect increased fat indicating organ degradation. In the future, the researchers plan to select the characteristics of each cell type by recruiting machine learning algorithms to automate cell differentiation. McMurray and colleagues still need to determine if the cell's spectral signature will remain consistent in the body or will change with position. As a potential medical use, they also want to know if this person will get sick when the infrared label of a person's cell changes. However, to date, researchers have only analyzed the tissues of mice. "We want to ensure the robustness of this approach," McMurray said. There is a significant limitation to the new technology. Synchrotrons are bulky, costly, and sparse, and they often have a list of studies that have to wait for months. "You can't bring the synchrotron into the hospital," Gardner said. But he pointed out that laboratory equipment is rapidly moving closer to the intensity of infrared light that can produce particle accelerators. McMurray added that after using a synchrotron to determine the unique spectral patterns of various cell types, the researchers plan to publish a catalog that allows other scientists to compare their sample results, even with labs with lower recognition capabilities. . Gardner expects the project to have some impact. “They have tools, technology, and experts to make this work faster.†(Jin Nan compiled) Chinese Journal of Science and Technology (2018-08-22 3rd Edition International) Source: Chinese Journal of Science Fingerprint Scanner,Biometric Fingerprint,Bluetooth Fingerprint Scanner,Wireless Fingerprint Scanner Shenzhen Bio Technology Co., Ltd , https://www.hfsecuritytech.com
Non-destructive detection technology? Let cells no longer "injured"