动物实验,巨噬细胞 z-bo 2020-09-29 378

　　In a new study, researchers at the University of Washington discovered that cell types commonly found in the vertebrate immune system play a unique role in the communication between other cells. They confirmed that cells called macrophages can send messages between non-immune cells.

　　This study describes how zebrafish pigment cells distribute macrophages to transmit information, which plays an important role in the formation of skin pigment patterns. This is the first report about macrophages relaying messages over long distances between non-immune cells. However, given that macrophages are common to all vertebrates, these researchers believe that their findings are not just about aquatic habits. Macrophages may be a common sender of remote messages between cells.

　　The corresponding author of the paper, David Parichy, a professor of biology at the University of Washington, said: "If pigment cells know how to use macrophages to send signals, then other cells do the same. There is a reason for this, it can Occurs in many kinds of cells and animals." Parichy and DaeSeokEom are the first authors of this article, PhD researchers and Zebrafish at the University of Washington. During the research, I discovered this new role of macrophages. They want to understand how zebrafish get silver and black bands. Black, yellow and silver come from different types of pigment cells. When zebrafish are young, these pigment cells migrate to the appropriate parts to form these bands.

　　Parichy said: "The communication between the three pigment cell groups during the transition is very important for the formation of bands observed in adult zebrafish."

　　Eom and Parichy used laboratory genetics with this tool to cause zebrafish pigment cells to fluoresce, making it easier to track them under the microscope. In the process, they found that at the peak of the formation of pigment patterns, xanthate shot peening, as the precursor of the yellow pigment cells, will produce unique and delicate protrusions. They named it Barge airineme after the mathematician and astronomer Sir George Airy and the Greek messenger goddess Iris.

　　Parichy said: "Xant Blast grows these tiny ridges in a circular fashion in almost random directions. These ridges will eventually meet another type of pigment cell, which is ferrite, and then. The growth will stop." Eom and Parichy found that these ridges contained small membrane-encapsulated protein vesicles, and the proteins in the vesicles provided molecular signals for melanocytes. They confirmed that when the bulge from Xantoblast encounters melanin, the protein that provides the molecular signal from the bulge moves the melanin into the band.

　　But they couldn't understand how melanite was found on these ridges, or why they took such a seemingly random route before Eom made important observations.

　　Eom said: "We observed that macrophages first interacted with one bulge and then with another bulge. In our experiments, we observed that it came from xanthan gum. Among 178 bulges. , 94% of them clearly interact with macrophages."

　　Macrophages are constantly migrating. Among the fish, people and creatures between the two on the evolving tree, they hover in the tissues of the body, crawling like an amoeba. During the journey, they sampled the environment, picked up the debris and swallowed it. The spoilage they eat is usually fragments of harmless cells. However, if macrophages swallow pathogens or receive a signal from an invader to attack nearby cells, macrophages can send alerts to other cells in the immune system.

　　After understanding this knowledge, Eom tested whether macrophages really promote the dialogue between yellow pigment cells and melanocytes. He used genetic tools to feed zebrafish that lacked macrophages, and observed that the xanthate squirt produced far fewer ridges. In this case, the melanocytes cannot move properly to form bands. when

　　When macrophages randomly encounter bumps, Eom uses a microscope to capture photos and videos of the behavior of macrophages. The macrophage seems to have swallowed the end of the spherical protein vesicle on the convex surface and dragged it to move and stretch the convex surface.

　　Eom said: "I understand why the bumps seem to follow random routes during this circumvention. They are dragged by randomly moving macrophages."

　　But when this kind of macrophage encounters melanocytes, the bump seems to have switched and moved from this melanin site, and it is possible to send information to the melanin site through the bump. Eom confirmed that the raised protein vesicles from xanthogen cells contained lipids. This is a kind of "feeding" signal from macrophages, which can explain why macrophages attach. Drag this bump. He and Parritch plan to study why macrophages do not swallow ridges, and how they can specifically transform from ridges into black iron ore.

　　However, considering that macrophages like to roam and pick up objects, Parridge believes that macrophages are not the only example of cell distribution outside the immune system.

　　Parichy said: "The behavior of macrophages observed in this study can occur in other environments that play an important role (tissue development and regeneration, cancer, etc.). It is easy to observe. Macrophages are in various situations. You How to promote signal transmission between units?"