Immunity: how can immune cells turn on "attack" mode?

January 9, 2020 / BIOON / -- recently, an international magazine, immunology In the previous research report, scientists from Bonn University found that macrophages often have two sides In healthy tissues, macrophages can play an important role and support the body's environment; when they are infected, they will stop working and start catching pathogens; once they are exposed to bacteria In a few minutes, macrophages will rapidly change the metabolic state of cells; relevant research results may help to develop new vaccine strategies, and also help to develop new therapies for autoimmune diseases Image source: Rolf m ü ller / UKB Macrophages are usually able to "smell" foreign invaders Their cell surface contains a large number of receptors called toll like receptors Their working principle is similar to that of olfactory receptors in the nasal cavity When encountering special chemical signals, these receptors will be activated, and the alarms induced by them will trigger a series of reactions in the cell During this period, macrophages will start inflammatory reactions, Now researchers don't know how macrophages change metabolism in the first few minutes Toll like receptors are divided into several different types, each of which responds to different odors, and these molecules become important risk signals in the evolution process, including so-called lipopolysaccharides (LPS), which are bacteria, the researchers said The main component of the cell wall, now researchers can use LPS to "fight" macrophages and clarify what will happen in the next few minutes or even hours When LPS comes into contact with macrophages, the metabolism of macrophages will change rapidly, and they will absorb a lot of glucose from the environment This is not mainly to obtain energy On the contrary, cells will convert sugars into so-called acetyl (small molecules related to acetic acid), which will then serve as a label in the nucleus and can be used for labeling Record genome sequences for further study Researchers Lauterbach explained that DNA is actually a very thin line one meter long, but it is very difficult to store in this form, which is why it rolls on many small spools (histones); enzymes can connect acetyl groups to specific parts of histones, and this process will be stimulated by the increase of acetyl synthesis after the alarm rings, which will eventually lead to DNA spiraling Loose, which makes the genes easier to read, include those responsible for signaling inflammation or improving macrophage mobility For a long time, researchers have known that the activation of Toll like receptors can change the reading of genes However, the mechanism that causes this situation is different from the one that researchers have found at present This newly discovered mechanism can help promote genetics As for the fine regulation of the response, the relevant research results can also provide a new starting point, such as improving the effectiveness of vaccination, etc.; toll like receptor plays a key role in the process of mediating acquired immune response, which will increase the efficiency of the body's defense mechanism against infection In many diseases, such as rheumatoid arthritis, the immune response of the body is often misled or too strong Dr Latz pointed out that the mechanism we found may help effectively inhibit harmful inflammatory processes without inhibiting the immune system; macrophages can once again focus on their own role, rather than capturing invaders permanently Original source: Mario a Lauterbach, Jasmin E Hanke, magdalini serefidou, et al Total like receiver signaling rewires macrophase metabolism and promotes histone acquisition via ATP City lyase, immunity (2019) Doi: 10.1016/j.immuni.2019.11.009